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Sample records for k40 gamma emissions

  1. Assessment of 40K levels in foodstuffs by gamma spectrometry

    International Nuclear Information System (INIS)

    Chinnaesakki, S.; Sartandel, S.J.; Bara, S.V.; Krishna, N.S.; Vinod Kumar, A.; Tripathi, R.M.; Puranik, V.D.

    2012-01-01

    Potassium-40 ( 40 K) is a naturally occurring radioactive isotope of potassium. Radioactive potassium-40 comprises a very small fraction(0.012%) of naturally occurring potassium, which is an element found in large amounts throughout nature. The half-life of 40 K is 1.3 billion years, and it decays to calcium-40 ( 40 Ca) by emitting a beta particle (89 %) and to the argon-40 ( 40 Ar) gas by electron capture with the emission of an energetic gamma ray of energy 1460 keV (10.7%). Humans require potassium to sustain biological processes, with most including 40 K being almost completely absorbed upon ingestion, moving quickly from the gastrointestinal tract to the blood stream (ANL-EVS, 2007). The body content of potassium is under homeostatic control. The total annual effective dose due to inhalation and ingestion of terrestrial radionuclides is assessed to be 0.29 mSv, of which 0.17mSv is due to 40 K and 0.12 mSv to the long-lived radionuclides in the uranium and thorium series (UNSCEAR 2008). Hence, measurement of 40 K in foodstuff is very much essential. This paper discusses the measurement of 40 K in foodstuffs samples collected in and around the new Bhabha Atomic Research Centre campus, Vishakhapatnam, Andhra Pradesh. This study was carried out as part of the baseline radiological monitoring

  2. Measurement of {sup 40}K by Cerenkov Effect in foods; Medicion de {sup 40}K por Efecto Cerenkov en alimentos

    Energy Technology Data Exchange (ETDEWEB)

    Davila R, J. I.; Cancino T, F.; Lopez del R, H.; Mireles G, F., E-mail: idavilara@gmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98060 Zacatecas (Mexico)

    2013-10-15

    The {sup 40}K is a natural radioactive isotope of the potassium element that decays mainly by beta and gamma radiation emission. Although the gamma spectrometry is generally used for its measuring, the energy of the beta radiation is enough to produce Cerenkov radiation in water. Taking advantage of the high efficiency of the liquid scintillation counting, a procedure to measure {sup 40}K was developed through the Cerenkov radiation using a liquid scintillation counter. The methodology was applied in foods with high content of potassium like tomato, banana, and in olive. The efficiency and sensibility of the counting were superior to those reported for gamma spectrometry and the chemical recovery of potassium was of 82.3%. The activity of {sup 40}K varied between 2.9 and 8.4 Bq/kg in banana, between 12.3 and 19 Bq/kg in tomato, and in olive was minor to the detectable minimum activity of the method. (Author)

  3. Determination of potassium by means of the {sup 40}K measurement; Determinacion de potasio mediante la medicion del {sup 40}K

    Energy Technology Data Exchange (ETDEWEB)

    Escareno J, E.; Vega C, H. R., E-mail: edmundoej@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2011-11-15

    The concentration of total potassium through the gamma-rays measurement of 1461 KeV emitted during the disintegration of the {sup 40}K was determined. In the nature three isotopes of the K exist: {sup 39}K, {sup 41}K and {sup 40}K, this last is radioactive with a half life of 1.2 x 10{sup 9} years. The {sup 40}K isotope is in a relationship of 0.0117% with regard to the K, this characteristic is used with the purpose of estimating the total quantity of potassium. The potassium has a very important paper in the growth and the reproduction of animals and plants. Due to the secular equilibrium, the emission of {gamma}-rays is proportional to the concentration of K. In this work a group of calibration sources were prepared and a spectrometry system was characterized with NaI(Tl) to determine the concentration of total K. (Author)

  4. Measurement of 40K by Cerenkov Effect in foods

    International Nuclear Information System (INIS)

    Davila R, J. I.; Cancino T, F.; Lopez del R, H.; Mireles G, F.

    2013-10-01

    The 40 K is a natural radioactive isotope of the potassium element that decays mainly by beta and gamma radiation emission. Although the gamma spectrometry is generally used for its measuring, the energy of the beta radiation is enough to produce Cerenkov radiation in water. Taking advantage of the high efficiency of the liquid scintillation counting, a procedure to measure 40 K was developed through the Cerenkov radiation using a liquid scintillation counter. The methodology was applied in foods with high content of potassium like tomato, banana, and in olive. The efficiency and sensibility of the counting were superior to those reported for gamma spectrometry and the chemical recovery of potassium was of 82.3%. The activity of 40 K varied between 2.9 and 8.4 Bq/kg in banana, between 12.3 and 19 Bq/kg in tomato, and in olive was minor to the detectable minimum activity of the method. (Author)

  5. Dose due to {sup 40}K

    Energy Technology Data Exchange (ETDEWEB)

    Escareno J, E.; Vega C, H. R., E-mail: edmundoej@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2011-10-15

    The dose due to {sup 40}K has been estimated. Potassium is one of the most abundant elements in nature, being approximately 2% of the Earth's crust. Potassium has three isotopes {sup 39}K, {sup 40}K and {sup 41}K, two are stable while {sup 40}K is radioactive with a half life of 1.2x10{sup 9} years; there is 0.0117% {sup 40}K-to-K ratio. Potassium plays an important role in plants, animals and humans growth and reproduction. Due to the fact that K is an essential element for humans, {sup 40}K is the most abundant radioisotope in human body. In order to keep good health conditions K must be intake at daily basis trough food and beverages, however when K in ingested above the requirements produce adverse health effects in persons with renal, cardiac and hypertension problems or suffering diabetes. In 89.3% {sup 40}K decays to {sup 40}C through {beta}-decay, in 10.3% decays through electronic capture and emitting 1.46 MeV {gamma}-ray. K is abundant in soil, construction materials, sand thus {gamma}-rays produced during {sup 40}K decay contribute to external dose. For K in the body practically all {sup 40}K decaying energy is absorbed by the body; thus {sup 40}K contributes to total dose in humans and it is important to evaluate its contribution. In this work a set of {sup 40}K sources were prepared using different amounts of KCl salt, a {gamma}-ray spectrometer with a NaI(Tl) was characterized to standardized the sources in order to evaluate the dose due to {sup 40}K. Using thermoluminescent dosemeters the dose due to {sup 40}K was measured and related to the amount of {sup 40}K {gamma}-ray activity. (Author)

  6. Measurement of K{sup {+-}}{yields}{pi}{sup {+-}}{gamma}{gamma} decays

    Energy Technology Data Exchange (ETDEWEB)

    Morales Morales, Cristina

    2009-07-21

    The goal of this thesis was an experimental test of an effective theory of strong interactions at low energy, called Chiral Perturbation Theory (ChPT). Weak decays of kaon mesons provide such a test. In particular, K{sup {+-}} {yields} {pi}{sup {+-}}{gamma}{gamma} decays are interesting because there is no tree-level O(p{sup 2}) contribution in ChPT, and the leading contributions start at O(p{sup 4}). At this order, these decays include one undetermined coupling constant, c. Both the branching ratio and the spectrum shape of K{sup {+-}} {yields} {pi}{sup {+-}}{gamma}{gamma} decays are sensitive to this parameter. O(p{sup 6}) contributions to K{sup {+-}} {yields} {pi}{sup {+-}}{gamma}{gamma} ChPT predict a 30-40% increase in the branching ratio. From the measurement of the branching ratio and spectrum shape of K{sup {+-}} {yields} {pi}{sup {+-}}{gamma}{gamma} decays, it is possible to determine a model dependent value of c and also to examine whether the O(p{sup 6}) corrections are necessary and enough to explain the rate. About 40% of the data collected in the year 2003 by the NA48/2 experiment have been analyzed and 908 K{sup {+-}} {yields} {pi}{sup {+-}}{gamma}{gamma} candidates with about 8% background contamination have been selected in the region with z=m{sup 2}{sub {gamma}}{sub {gamma}}/m{sub K}{sup 2}{>=}0.2. Using 5,750,121 selected K{sup {+-}} {yields} {pi}{sup {+-}}{pi}{sup 0} decays as normalization channel, a model independent differential branching ratio of K{sup {+-}} {yields} {pi}{sup {+-}}{gamma}{gamma} has been measured to be: BR(K{sup {+-}} {yields} {pi}{sup {+-}}{gamma}{gamma}, z{>=}0.2)=(1.018{+-}0.038{sub stat}{+-}0.039{sub syst}{+-}0.004{sub ext}).10{sup -6}. From the fit to the O(p{sup 6}) ChPT prediction of the measured branching ratio and the shape of the z-spectrum, a value of c=1.54{+-}0.15{sub stat}{+-}0.18{sub syst} has been extracted. Using the measured c value and the O(p{sup 6}) ChPT prediction, the branching ratio for z=m{sup 2}{sub

  7. A study of the radiative K{sub L}{yields}{pi}{sup {+-}}e{sup -+}{nu}{gamma} decay and search for direct photon emission with the KLOE detector

    Energy Technology Data Exchange (ETDEWEB)

    Ambrosino, F.; Chiefari, G.; Massarotti, P.; Meola, S.; Napolitano, M.; Perfetto, F.; Saracino, G. [Univ. ' Federico II' , Dipt. di Scienze Fisiche, Napoli (Italy)]|[INFN Sezione di Napoli, Napoli (Italy); Antonelli, A.; Antonelli, M.; Bencivenni, G.; Bertolucci, S.; Bloise, C.; Bossi, F.; Campana, P.; Capon, G.; Capussela, T.; Chi, S.; Ciambrone, P.; De Lucia, E.; De Simone, P.; Dreucci, M.; Felici, G.; Ferrari, A.; Ferrer, M.L.; Forti, C.; Gatti, C.; Giovannella, S.; Lanfranchi, G.; Mei, W.; Miscetti, S.; Moulson, M.; Mueller, S.; Murtas, F.; Palutan, M.; Santangelo, P.; Sciascia, B.; Sibidanov, A.; Spadaro, T.; Venanzoni, G. [Lab. Nazionali di Frascati dell' INFN, Frascati (Roma) (Italy); Archilli, F. [Univ. ' Tor Vergata' , Dipt. di Fisica, Roma (Italy)]|[INFN Sezione di Roma Tor Vergata, Roma (Italy); Bacci, C.; Bocchetta, S.; Ceradini, F.; Cesario, F.; Di Micco, B.; Nguyen, F. [Univ. ' Roma Tre' , Dipt. di Fisica, Roma (Italy)]|[INFN Sezione di Roma Tre, Roma (Italy); Beltrame, P.; Denig, A.; Kluge, W.; Leone, D. [Univ. et Karlsruhe, Inst. fuer Experimentelle Kernphysik, Karlsruhe (Germany); Bini, C.; Caloi, R.; De Santis, A.; De Zorzi, G.; Di Domenico, A.; Fiore, S.; Franzini, P.; Gauzzi, P.; Lacava, F.; Testa, M. [Univ. ' La Sapienza' , Dipt. di Fisica, Roma (Italy)]|[INFN Sezione di Roma, Roma (Italy); Branchini, P.; Graziani, E.; Passeri, A.; Tortora, L. [INFN Sezione di Roma Tre, Roma (Italy); Crucianelli, F. [Univ. ' La Sapienza' , Dipt. di Fisica, Roma (Italy); Di Donato, C.; Doria, A. [INFN Sezione di Napoli, Napoli (Italy); Gorini, E. [Univ. Lecce, Dipt. di Fisica, Lecce (Italy)]|[INFN Sezione di Lecce, Lecce (Italy); Kulikov, V. [Inst. for Theoretical and Experimental Physics, Moscow (Russian Federation); Lee-Franzini, J. [Lab. Nazionali di Frascati dell' INFN, Frascati (Roma) (Italy)]|[State Univ. of New York, Physics Dept., Stony Brook (United States)] [and others

    2008-06-15

    We present a measurement of the ratio R={gamma}(K{sup 0}{sub e3{gamma}};E{sup *}{sub {gamma}}>30 MeV, {theta}{sup *}{sub {gamma}}>20 )/{gamma}(K{sup 0}{sub e3}) and a first measurement of the direct emission contribution in semileptonic K{sub L} decays. The measurement was performed at the DA{phi}NE{phi} factory by selecting {phi}{yields}K{sub L}K{sub S} decays with the KLOE detector. We use 328 pb{sup -1} of data, corresponding to about 3.5 million K{sup 0}{sub e3} events and about 9000 K{sup 0}{sub e3{gamma}} radiative events. Our result is R=(924{+-}23{sub stat}{+-}16{sub syst}) x 10{sup -5} for the branching ratio and left angle X right angle =-2.3{+-}1.3{sub stat}{+-}1.4{sub syst} for the effective strength parameter describing direct emission. (orig.)

  8. Precise measurement of {gamma}(K{yields}e {nu}({gamma}))/{gamma}(K{yields}{mu} {nu}({gamma})) and study of K{yields}e {nu} {gamma}

    Energy Technology Data Exchange (ETDEWEB)

    Ambrosino, F.; Massarotti, P.; Meola, S.; Napolitano, M. [Dipartimento di Scienze Fisiche dell' Universita ' ' Federico II' ' , Napoli (Italy); INFN Sezione di Napoli, Napoli (Italy); Antonelli, A.; Antonelli, M.; Bencivenni, G.; Bloise, C.; Bossi, F.; Capon, G.; Capussela, T.; Ciambrone, P.; De Lucia, E.; De Simone, P.; Dreucci, M.; Felici, G.; Gatti, C.; Giovannella, S.; Jacewicz, M.; Lanfranchi, G.; Miscetti, S.; Moulson, M.; Murtas, F.; Palutan, M.; Santangelo, P.; Sciascia, B.; Sibidanov, A.; Spadaro, T.; Venanzoni, G. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Archilli, F. [Dipartimento di Fisica dell' Universita ' ' Tor Vergata' ' , Rome (Italy); INFN Sezione di Roma Tor Vergata, Rome (Italy); Beltrame, P.; Denig, A.; Mueller, S. [Johannes Gutenberg-Universitaet, Institut fuer Kernphysik, Mainz (Germany); Bini, C.; De Santis, A.; De Zorzi, G.; Di Domenico, A.; Fiore, S.; Franzini, P.; Gauzzi, P. [Dipartimento di Fisica dell' Universita ' ' La Sapienza' ' , Rome (Italy); INFN Sezione di Roma, Rome (Italy); Bocchetta, S.; Ceradini, F.; Di Micco, B.; Nguyen, F. [Dipartimento di Fisica dell' Universita ' ' Roma Tre' ' , Rome (Italy); INFN Sezione di Roma Tre, Rome (Italy); Branchini, P.; Graziani, E.; Passeri, A.; Tortora, L. [INFN Sezione di Roma Tre, Rome (Italy); Capriotti, D. [Dipartimento di Fisica dell' Universita ' ' Roma Tre' ' , Rome (Italy); Di Donato, C. [INFN Sezione di Napoli, Napoli (Italy); Kulikov, V. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Lee-Franzini, J. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); State University of New York, Physics Department, Stony Brook (United States); Martini, M.; Patera, V.; Versaci, R. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Dipartimento di Energetica dell' Universita ' ' La Sapienza' ' , Rome (Italy); Valente, P. [INFN Sezione di Roma, Rome (Italy)

    2009-12-15

    We present a precise measurement of the ratio R{sub K}={gamma}(K{yields}e{nu}({gamma}))/{gamma}(K{yields}{mu}{nu}({gamma})) and a study of the radiative process K{yields}e{nu}{gamma}, performed with the KLOE detector. The results are based on data collected at the Frascati e{sup +}e{sup -} collider DA {phi}NE for an integrated luminosity of 2.2 fb{sup -1}. We find R{sub K}=(2.493{+-}0.025{sub stat}{+-}0.019{sub syst}) x 10{sup -5}, in agreement with the Standard Model expectation. This result is used to improve constraints on parameters of the Minimal Supersymmetric Standard Model with lepton flavor violation. We also measured the differential decay rate d {gamma}(K{yields}e{nu}{gamma})/dE{sub {gamma}} for photon energies 10gamma}}<250 MeV. Results are compared with predictions from theory. (orig.)

  9. Determination of 228Th, 226Ra and 40K in Soil Using In-Situ GammaSpectrometer

    International Nuclear Information System (INIS)

    Bunawas; Wahyudi; Syarbaini; Untara

    2000-01-01

    Determination of natural radionuclide in latosol soil at six locationsaround PPTN Serpong by using Inspector portable gamma spectrometer with highpurity Germanium detector (HPGe) which has 26% relative efficiency had beenobtained. Radionuclides data of 228 Th, 226 Ra and 40 K were obtained in4 hours, shorter than laboratories analysis which needed 3 weeks. Thedifferences between in-situ measurement and laboratory were 3.6% to 56.2% forsix conditions of soil measured. According to the specific activity dataanalysis using statistic hypothesis, the result shows that the activity of 228 Th and 226 Ra are independent on location, but 40 K is dependent onlocation. (author)

  10. 134Cs emission probabilities determination by gamma spectrometry

    Science.gov (United States)

    de Almeida, M. C. M.; Poledna, R.; Delgado, J. U.; Silva, R. L.; Araujo, M. T. F.; da Silva, C. J.

    2018-03-01

    The National Laboratory for Ionizing Radiation Metrology (LNMRI/IRD/CNEN) of Rio de Janeiro performed primary and secondary standardization of different radionuclides reaching satisfactory uncertainties. A solution of 134Cs radionuclide was purchased from commercial supplier to emission probabilities determination of some of its energies. 134Cs is a beta gamma emitter with 754 days of half-life. This radionuclide is used as standard in environmental, water and food control. It is also important to germanium detector calibration. The gamma emission probabilities (Pγ) were determined mainly for some energies of the 134Cs by efficiency curve method and the Pγ absolute uncertainties obtained were below 1% (k=1).

  11. Evaluation of 40K and studies of its variation in occupational radiation workers of TAPS 1-4

    International Nuclear Information System (INIS)

    Nagaraju, G.; Rao, D.D.; Baburajan, A.

    2014-01-01

    Tarapur Maharashtra Site consists of two units (TAPS 1 and 2) of 160 MW(e) BWRs and two units (TAPS 3 and 4) of 540 MW(e) PHWRs in operation. Monitoring and dose assessment of all radiation workers is a regulatory requirement as per radiation safety procedures of operating stations based on AERB guidelines. Internal contamination and committed effective dose (CED) due to internally deposited gamma radionuclides is evaluated based on whole body counting measurements. The predominant nuclides of potential internal contamination continued to be 60 Co, 134+137 Cs and 131 I. Apart from these, natural radionuclide 40 K is also detected in the body of occupational workers. It is one of the most important nutrients distributed throughout the body, mainly in muscle and is an essential element in life process. It is under close homeostatic control in the body and is not influenced by the environmental levels. The daily intake of natural radionuclides of uranium and thorium series is almost negligible compared with that of 40 K, a radioisotope of potassium present to the extent of 0.012 % of natural Potassium. It has a halflife of 1.28 x 10 9 Y and decays by beta emission and electron capture accompanied by 1.46 MeV gamma ray emission with 10.7 % abundance. The specific activity of potassium is 31.5 Bq 40 K per gram of potassium. The paper presents the analysis of 40 K concentration in the workers of vegetarian and Non-vegetarian diet categories

  12. Limits on neutrino emission from gamma-ray bursts with the 40 string IceCube detector.

    Science.gov (United States)

    Abbasi, R; Abdou, Y; Abu-Zayyad, T; Adams, J; Aguilar, J A; Ahlers, M; Andeen, K; Auffenberg, J; Bai, X; Baker, M; Barwick, S W; Bay, R; Bazo Alba, J L; Beattie, K; Beatty, J J; Bechet, S; Becker, J K; Becker, K-H; Benabderrahmane, M L; BenZvi, S; Berdermann, J; Berghaus, P; Berley, D; Bernardini, E; Bertrand, D; Besson, D Z; Bindig, D; Bissok, M; Blaufuss, E; Blumenthal, J; Boersma, D J; Bohm, C; Bose, D; Böser, S; Botner, O; Braun, J; Brown, A M; Buitink, S; Carson, M; Chirkin, D; Christy, B; Clem, J; Clevermann, F; Cohen, S; Colnard, C; Cowen, D F; D'Agostino, M V; Danninger, M; Daughhetee, J; Davis, J C; De Clercq, C; Demirörs, L; Depaepe, O; Descamps, F; Desiati, P; de Vries-Uiterweerd, G; DeYoung, T; Díaz-Vélez, J C; Dierckxsens, M; Dreyer, J; Dumm, J P; Ehrlich, R; Eisch, J; Ellsworth, R W; Engdegård, O; Euler, S; Evenson, P A; Fadiran, O; Fazely, A R; Fedynitch, A; Feusels, T; Filimonov, K; Finley, C; Fischer-Wasels, T; Foerster, M M; Fox, B D; Franckowiak, A; Franke, R; Gaisser, T K; Gallagher, J; Geisler, M; Gerhardt, L; Gladstone, L; Glüsenkamp, T; Goldschmidt, A; Goodman, J A; Grant, D; Griesel, T; Gross, A; Grullon, S; Gurtner, M; Ha, C; Hallgren, A; Halzen, F; Han, K; Hanson, K; Heinen, D; Helbing, K; Herquet, P; Hickford, S; Hill, G C; Hoffman, K D; Homeier, A; Hoshina, K; Hubert, D; Huelsnitz, W; Hülss, J-P; Hulth, P O; Hultqvist, K; Hussain, S; Ishihara, A; Jacobsen, J; Japaridze, G S; Johansson, H; Joseph, J M; Kampert, K-H; Kappes, A; Karg, T; Karle, A; Kelley, J L; Kemming, N; Kenny, P; Kiryluk, J; Kislat, F; Klein, S R; Köhne, J-H; Kohnen, G; Kolanoski, H; Köpke, L; Kopper, S; Koskinen, D J; Kowalski, M; Kowarik, T; Krasberg, M; Krings, T; Kroll, G; Kuehn, K; Kuwabara, T; Labare, M; Lafebre, S; Laihem, K; Landsman, H; Larson, M J; Lauer, R; Lehmann, R; Lünemann, J; Madsen, J; Majumdar, P; Marotta, A; Maruyama, R; Mase, K; Matis, H S; Meagher, K; Merck, M; Mészáros, P; Meures, T; Middell, E; Milke, N; Miller, J; Montaruli, T; Morse, R; Movit, S M; Nahnhauer, R; Nam, J W; Naumann, U; Niessen, P; Nygren, D R; Odrowski, S; Olivas, A; Olivo, M; O'Murchadha, A; Ono, M; Panknin, S; Paul, L; Pérez de los Heros, C; Petrovic, J; Piegsa, A; Pieloth, D; Porrata, R; Posselt, J; Price, P B; Prikockis, M; Przybylski, G T; Rawlins, K; Redl, P; Resconi, E; Rhode, W; Ribordy, M; Rizzo, A; Rodrigues, J P; Roth, P; Rothmaier, F; Rott, C; Ruhe, T; Rutledge, D; Ruzybayev, B; Ryckbosch, D; Sander, H-G; Santander, M; Sarkar, S; Schatto, K; Schmidt, T; Schoenwald, A; Schukraft, A; Schultes, A; Schulz, O; Schunck, M; Seckel, D; Semburg, B; Seo, S H; Sestayo, Y; Seunarine, S; Silvestri, A; Slipak, A; Spiczak, G M; Spiering, C; Stamatikos, M; Stanev, T; Stephens, G; Stezelberger, T; Stokstad, R G; Stoyanov, S; Strahler, E A; Straszheim, T; Sullivan, G W; Swillens, Q; Taavola, H; Taboada, I; Tamburro, A; Tarasova, O; Tepe, A; Ter-Antonyan, S; Tilav, S; Toale, P A; Toscano, S; Tosi, D; Turčan, D; van Eijndhoven, N; Vandenbroucke, J; Van Overloop, A; van Santen, J; Vehring, M; Voge, M; Voigt, B; Walck, C; Waldenmaier, T; Wallraff, M; Walter, M; Weaver, C; Wendt, C; Westerhoff, S; Whitehorn, N; Wiebe, K; Wiebusch, C H; Williams, D R; Wischnewski, R; Wissing, H; Wolf, M; Woschnagg, K; Xu, C; Xu, X W; Yodh, G; Yoshida, S; Zarzhitsky, P

    2011-04-08

    IceCube has become the first neutrino telescope with a sensitivity below the TeV neutrino flux predicted from gamma-ray bursts if gamma-ray bursts are responsible for the observed cosmic-ray flux above 10(18)  eV. Two separate analyses using the half-complete IceCube detector, one a dedicated search for neutrinos from pγ interactions in the prompt phase of the gamma-ray burst fireball and the other a generic search for any neutrino emission from these sources over a wide range of energies and emission times, produced no evidence for neutrino emission, excluding prevailing models at 90% confidence.

  13. Expression of human gamma-globin genes in human erythroleukemia (K562) cells.

    Science.gov (United States)

    Donovan-Peluso, M; Acuto, S; Swanson, M; Dobkin, C; Bank, A

    1987-12-15

    K562 cells express embryonic (epsilon) and fetal (gamma) globins and hemoglobins but not adult (beta) globin. To define the cis acting regulatory elements involved in the discrimination between gamma and beta genes, we have constructed chimeric genes composed of portions of gamma and beta and evaluated their expression in stable K562 transfectants. A gamma beta fusion gene containing gamma 5' sequences to the EcoRI site in exon 3 and beta sequences 3' is expressed at 10-40% that of the endogenous gamma level. In 50% of the lines, this fusion gene appropriately increases its expression in response to hemin, an inducer of endogenous globin gene expression in K562 cells. In contrast, a beta gamma fusion gene, containing beta sequences 5' to the EcoRI site in exon 3 and gamma sequences 3', is neither expressed nor correctly initiated. A beta gene containing gamma-intervening sequence (IVS) 2 accumulates an mRNA transcript when analyzed with a 3' beta probe. However, no correctly initiated beta mRNA is observed. A gamma gene with beta-IVS 2 is only inducible in one of six expressing clones. All the results are consistent with the presence of stage-specific trans acting factors in K562 cells that stimulate expression of gamma genes and suggest a significant role for gamma-IVS 2 in gamma gene expression.

  14. {sup 134}Cs emission probabilities determination by gamma spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, M.C.M. de, E-mail: candida@cnen.gov.br [Comissão Nacional de Energia Nuclear (DINOR/CNEN), Riode Janeiro, RJ (Brazil); Poledna, R.; Delgado, J.U.; Silva, R.L.; Araujo, M.T.; Silva, C.J. da [Instituto de Radioproteção e Dosimetria (LNMRI/IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-07-01

    The National Laboratory for Ionizing Radiation Metrology (LNMRI/IRD/CNEN) of Rio de Janeiro performed primary and secondary standardization of different radionuclides reaching satisfactory uncertainties. A solution of {sup 134}Cs radionuclide was purchased from commercial supplier to emission probabilities determination of some of its energies. {sup 134}Cs is a beta gamma emitter with 754 days of half-life. This radionuclide is used as standard in environmental, water and food control. It is also important to germanium detector calibration.The gamma emission probabilities (Pγ) were determined mainly for some energies of the {sup 134}Cs by efficiency curve method and the Pγ absolute uncertainties obtained were below 1% (k=1). (author)

  15. CONSTRAINTS ON THE EMISSION GEOMETRIES AND SPIN EVOLUTION OF GAMMA-RAY MILLISECOND PULSARS

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, T. J. [National Research Council Research Associate, National Academy of Sciences, Washington, DC 20001 (United States); Venter, C. [Centre for Space Research, North-West University, Potchefstroom Campus, Private Bag X6001, 2520 Potchefstroom (South Africa); Harding, A. K.; Çelik, Ö.; Ferrara, E. C. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Guillemot, L. [Laboratoire de Physique et Chimie de l' Environnement, LPCE UMR 6115 CNRS, F-45071 Orléans Cedex 02 (France); Smith, D. A.; Hou, X. [Centre d' Études Nucléaires de Bordeaux Gradignan, IN2P3/CNRS, Université Bordeaux 1, BP120, F-33175 Gradignan Cedex (France); Kramer, M. [Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn (Germany); Den Hartog, P. R. [W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States); Lande, J. [Twitter Inc., 1355 Market Street 900, San Francisco, CA 94103 (United States); Ray, P. S., E-mail: tyrel.j.johnson@gmail.com, E-mail: Christo.Venter@nwu.ac.za, E-mail: ahardingx@yahoo.com [Space Science Division, Naval Research Laboratory, Washington, DC 20375-5352 (United States)

    2014-07-01

    Millisecond pulsars (MSPs) are a growing class of gamma-ray emitters. Pulsed gamma-ray signals have been detected from more than 40 MSPs with the Fermi Large Area Telescope (LAT). The wider radio beams and more compact magnetospheres of MSPs enable studies of emission geometries over a broader range of phase space than non-recycled radio-loud gamma-ray pulsars. We have modeled the gamma-ray light curves of 40 LAT-detected MSPs using geometric emission models assuming a vacuum retarded-dipole magnetic field. We modeled the radio profiles using a single-altitude hollow-cone beam, with a core component when indicated by polarimetry; however, for MSPs with gamma-ray and radio light curve peaks occurring at nearly the same rotational phase, we assume that the radio emission is co-located with the gamma rays and caustic in nature. The best-fit parameters and confidence intervals are determined using a maximum likelihood technique. We divide the light curves into three model classes, with gamma-ray peaks trailing (Class I), aligned (Class II), or leading (Class III) the radio peaks. Outer gap and slot gap (two-pole caustic) models best fit roughly equal numbers of Class I and II, while Class III are exclusively fit with pair-starved polar cap models. Distinguishing between the model classes based on typical derived parameters is difficult. We explore the evolution of the magnetic inclination angle with period and spin-down power, finding possible correlations. While the presence of significant off-peak emission can often be used as a discriminator between outer gap and slot gap models, a hybrid model may be needed.

  16. CONSTRAINTS ON THE EMISSION GEOMETRIES AND SPIN EVOLUTION OF GAMMA-RAY MILLISECOND PULSARS

    International Nuclear Information System (INIS)

    Johnson, T. J.; Venter, C.; Harding, A. K.; Çelik, Ö.; Ferrara, E. C.; Guillemot, L.; Smith, D. A.; Hou, X.; Kramer, M.; Den Hartog, P. R.; Lande, J.; Ray, P. S.

    2014-01-01

    Millisecond pulsars (MSPs) are a growing class of gamma-ray emitters. Pulsed gamma-ray signals have been detected from more than 40 MSPs with the Fermi Large Area Telescope (LAT). The wider radio beams and more compact magnetospheres of MSPs enable studies of emission geometries over a broader range of phase space than non-recycled radio-loud gamma-ray pulsars. We have modeled the gamma-ray light curves of 40 LAT-detected MSPs using geometric emission models assuming a vacuum retarded-dipole magnetic field. We modeled the radio profiles using a single-altitude hollow-cone beam, with a core component when indicated by polarimetry; however, for MSPs with gamma-ray and radio light curve peaks occurring at nearly the same rotational phase, we assume that the radio emission is co-located with the gamma rays and caustic in nature. The best-fit parameters and confidence intervals are determined using a maximum likelihood technique. We divide the light curves into three model classes, with gamma-ray peaks trailing (Class I), aligned (Class II), or leading (Class III) the radio peaks. Outer gap and slot gap (two-pole caustic) models best fit roughly equal numbers of Class I and II, while Class III are exclusively fit with pair-starved polar cap models. Distinguishing between the model classes based on typical derived parameters is difficult. We explore the evolution of the magnetic inclination angle with period and spin-down power, finding possible correlations. While the presence of significant off-peak emission can often be used as a discriminator between outer gap and slot gap models, a hybrid model may be needed

  17. X-Ray-Driven Gamma Emission

    International Nuclear Information System (INIS)

    Carroll, J. J.; Karamian, S. A.; Rivlin, L. A.; Zadernovsky, A. A.

    2001-01-01

    X-ray-driven gamma emission describes processes that may release nuclear energy in a 'clean' way, as bursts of incoherent or coherent gamma rays without the production of radioactive by-products. Over the past decade, studies in this area, as a part of the larger field of quantum nucleonics, have gained tremendous momentum. Since 1987 it has been established that photons could trigger gamma emission from a long-lived metastable nuclear excited state of one nuclide and it appears likely that triggering in other isotopes will be demonstrated conclusively in the near future. With these experimental results have come new proposals for the creation of collective and avalanche-like incoherent gamma-ray bursts and even for the ultimate light source, a gamma-ray laser. Obviously, many applications would benefit from controlled bursts of gamma radiation, whether coherent or not. This paper reviews the experimental results and concepts for the production of gamma rays, driven by externally produced X-rays

  18. Gamma-ray emission spectra from spheres with 14 MeV neutron source

    International Nuclear Information System (INIS)

    Yamamoto, Junji; Kanaoka, Takeshi; Murata, Isao; Takahashi, Akito; Sumita, Kenji

    1989-01-01

    Energy spectra of neutron-induced gamma-rays emitted from spherical samples were measured using a 14 MeV neutron source. The samples in use were LiF, Teflon:(CF 2 ) n , Si, Cr, Mn, Co, Cu, Nb, Mo, W and Pb. A diameter of the sphere was either 40 or 60 cm. The gamma-ray energy in the emission spectra covered the range from 500 keV to 10 MeV. Measured spectra were compared with transport calculations using the nuclear data files of JENDL-3T and ENDF/B-IV. The agreements between the measurements and the JENDL-3T calculations were good in the emission spectra for the low energy gamma-rays from inelastic scattering. (author)

  19. K concentration in seven rice varieties and two infusions (coffee and tea) determined by 40K-40Ar radioactive decay

    International Nuclear Information System (INIS)

    Navarrete, J.M.; Cabrera, L.; Martinez, T.

    2005-01-01

    As a result of the event occurred in Mexico about 20 years ago, by which milk powder contaminated with 137 CS was imported from an European country after the Chernobyl accident, a legal disposition was set up in the country in order to certify the absence of radioactive contamination by gamma emitters, performing gamma spectroscopy to every foodstuff sample either imported or to be exported. In this process is always detected the X rays (1461 KeV) natural radiation emitted by 11% of 40 K nucleus decaying to 40 Ar by EC. So, when the counts accumulated during a detection time from 12 to 24 hours in a low background scintillation detection system are expressed as cps, corrected for background and divided by the sample weight (g), detection efficiency (%), decay yielding (0.11) and constant specific activity of elementary K(31.19 Bq/gK), the K concentration in the sample .is obtained. This paper reports the results found in seven rice varieties and two more vegetables, coffee and tea, including the K fractions passing to infusions, as well as are discussed similarities and differences related to K concentration and the advantages of the method.

  20. 137Cs and 40K levels in marine species caught in Malaysian waters

    International Nuclear Information System (INIS)

    Dougherty, G.; Ng, C.E.

    1982-01-01

    Activity levels of 137 Cs and 40 K in a variety of marine species caught in the Indian Ocean and S. China Seas, between Jan. 1980 - Sept. 1981, have been monitored, using gamma spectroscopy. Samples were dried to constant weight, powdered, and a constant volume used for gamma spectroscopy. Radioactivity levels and concentration factors for 40 K and 137 Cs are presented. 137 Cs concentration factors are found to vary greatly between species caught in the same area, possibly due to different feeding patterns and levels. (U.K.)

  1. High-energy gamma-ray emission in compact binaries

    International Nuclear Information System (INIS)

    Cerutti, Benoit

    2010-01-01

    Four gamma-ray sources have been associated with binary systems in our Galaxy: the micro-quasar Cygnus X-3 and the gamma-ray binaries LS I +61 degrees 303, LS 5039 and PSR B1259-63. These systems are composed of a massive companion star and a compact object of unknown nature, except in PSR B1259-63 where there is a young pulsar. I propose a comprehensive theoretical model for the high-energy gamma-ray emission and variability in gamma-ray emitting binaries. In this model, the high-energy radiation is produced by inverse Compton scattering of stellar photons on ultra-relativistic electron-positron pairs injected by a young pulsar in gamma-ray binaries and in a relativistic jet in micro-quasars. Considering anisotropic inverse Compton scattering, pair production and pair cascade emission, the TeV gamma-ray emission is well explained in LS 5039. Nevertheless, this model cannot account for the gamma-ray emission in LS I +61 degrees 303 and PSR B1259-63. Other processes should dominate in these complex systems. In Cygnus X-3, the gamma-ray radiation is convincingly reproduced by Doppler-boosted Compton emission of pairs in a relativistic jet. Gamma-ray binaries and micro-quasars provide a novel environment for the study of pulsar winds and relativistic jets at very small spatial scales. (author)

  2. Proceedings of the First International Induced Gamma Emission Workshop

    International Nuclear Information System (INIS)

    Popescu, I.I.; Ur, C.A.

    1999-01-01

    The proceedings of the First International Induced Gamma Emission Workshop held on August 16-20, 1997 in Predeal, Romania contain 40 communications. These are bunched in the following 7 sections: 1. Opening session (8 papers); 2. Theory and Modelling (7 papers); 3. Pump Mechanisms (6 papers); 4. Pump Sources (3 papers); 5. Collective Effects (8 papers); 6. Nuclear Isomers (3 papers); 7. Moessbauer Effect (5 papers)

  3. Inverse compton emission of gamma rays near the pulsar surface

    International Nuclear Information System (INIS)

    Morini, M.

    1981-01-01

    The physical conditions near pulsar surface that might give rise to gamma ray emission from Crab and Vela pulsars are not yet well understood. Here I suggest that, in the context of the vacuum discharge mechanism proposed by Ruderman and Sutherland (1975), gamma rays are produced by inverse Compton scattering of secondary electrons with the thermal radiation of the star surface as well as for curvature and synchotron radiation. It is found that inverse Compton scattering is relevant if the neutron star surface temperature is greater than 10 6 K or of the polar cap temperature is of the order of 5 x 10 6 K. Inverse Compton scattering in anisotropic photon fields and Klein-Nishina regime is here carefully considered. (orig.)

  4. Gamma-ray emission profile measurements during JET ICRH discharges

    Energy Technology Data Exchange (ETDEWEB)

    Howarth, P.J.A. [Birmingham Univ. (United Kingdom); Adams, J.M.; Bond, D.S.; Watkins, N. [AEA Technology, Harwell (United Kingdom); Jarvis, O.N.; Marcus, F.B.; Sadler, G.; Belle, P. van [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking

    1994-12-31

    Ion Cyclotron Resonant Heating (ICRH) that is tuned to minority fuel ions can induce an energy diffusion of the heated species and create high energy tail temperatures of {approx} 1 MeV. The most energetic of these accelerated minority ions can undergo nuclear reactions with impurity Be and C that produces {gamma}-ray emission from the decay of the excited product nuclei. This RF-induced {gamma}-ray emission has been recorded using the JET neutron emission profile diagnostic which is capable of distinguishing neutrons and {gamma}-rays. Appropriate data processing has enabled the RF-induced {gamma}-ray emission signals to be isolated from the {gamma}-ray emission signals associated with neutron interactions in the material surrounding the profile monitor. The 2-d {gamma}-ray emission profiles show that virtually all the radiation originates from the low field side of the RF resonance layer, as expected from RF-induced pitch angle diffusion. The emission profiles indicate the presence of a small population of resonant {sup 3}He ions that possess orbits lying near the passing-trapped boundary. (author) 6 refs., 4 figs.

  5. MCNP modelling of scintillation-detector gamma-ray spectra from natural radionuclides

    NARCIS (Netherlands)

    Hendriks, Peter; Maucec, M; de Meijer, RJ

    gamma-ray spectra of natural radionuclides are simulated for a BGO detector in a borehole geometry using the Monte Carlo code MCNP. All gamma-ray emissions of the decay of K-40 and the series of Th-232 and U-238 are used to describe the source. A procedure is proposed which excludes the

  6. {sup 41}K(n, {gamma}){sup 42}K thermal and resonance integral cross section measurements

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, F.A. Jr.; Maidana, N.L.; Vanin, V.R. [Sao Paulo Univ., SP (Brazil). Lab. do Acelerador Linear; Dias, M.S.; Koskinas, M.F. [IPEN-CNEN, Sao Paulo, SP (Brazil). Lab. de Metrolgia Nuclear; Lopez-Pino, N. [Instituto Superior de Tecnolgias y Ciencias Aplicadas (InSTEC), Habana (Cuba)

    2012-07-01

    We measured the {sup 41}K thermal neutron absorption and resonance integral cross sections after the irradiation of KNO{sub 3} samples near the core of the IEA-R1 IPEN pool-type research reactor. Bare and cadmium-covered targets were irradiated in pairs with Au-Al alloy flux-monitors. The residual activities were measured by gamma-ray spectroscopy with a HPGe detector, with special care to avoid the {sup 42}K decay {beta}{sup -} emission effects on the spectra. The gamma-ray self-absorption was corrected with the help of MCNP simulations. We applied the Westcott formalism in the average neutron flux determination and calculated the depression coefficients for thermal and epithermal neutrons due to the sample thickness with analytical approximations. We obtained 1.57(4) b and 1.02(4) b, for thermal and resonance integral cross sections, respectively, with correlation coefficient equal to 0.39.

  7. Egret observations of the extragalactic gamma-ray emission

    DEFF Research Database (Denmark)

    Sreekumar, P.; Bertsch, D.L.; Dingus, B.L.

    1998-01-01

    The all-sky survey in high-energy gamma rays (E > 30 MeV) carried out by EGRET aboard the Compton Gamma Ray Observatory provides a unique opportunity to examine in detail the diffuse gamma-ray emission. The observed diffuse emission has a Galactic component arising from cosmic-ray interactions wi...

  8. A link between prompt optical and prompt gamma-ray emission in gamma-ray bursts.

    Science.gov (United States)

    Vestrand, W T; Wozniak, P R; Wren, J A; Fenimore, E E; Sakamoto, T; White, R R; Casperson, D; Davis, H; Evans, S; Galassi, M; McGowan, K E; Schier, J A; Asa, J W; Barthelmy, S D; Cummings, J R; Gehrels, N; Hullinger, D; Krimm, H A; Markwardt, C B; McLean, K; Palmer, D; Parsons, A; Tueller, J

    2005-05-12

    The prompt optical emission that arrives with the gamma-rays from a cosmic gamma-ray burst (GRB) is a signature of the engine powering the burst, the properties of the ultra-relativistic ejecta of the explosion, and the ejecta's interactions with the surroundings. Until now, only GRB 990123 had been detected at optical wavelengths during the burst phase. Its prompt optical emission was variable and uncorrelated with the prompt gamma-ray emission, suggesting that the optical emission was generated by a reverse shock arising from the ejecta's collision with surrounding material. Here we report prompt optical emission from GRB 041219a. It is variable and correlated with the prompt gamma-rays, indicating a common origin for the optical light and the gamma-rays. Within the context of the standard fireball model of GRBs, we attribute this new optical component to internal shocks driven into the burst ejecta by variations of the inner engine. The correlated optical emission is a direct probe of the jet isolated from the medium. The timing of the uncorrelated optical emission is strongly dependent on the nature of the medium.

  9. DISCOVERY OF TeV GAMMA-RAY EMISSION FROM CTA 1 BY VERITAS

    Energy Technology Data Exchange (ETDEWEB)

    Aliu, E.; Errando, M. [Department of Physics and Astronomy, Barnard College, Columbia University, NY 10027 (United States); Archambault, S. [Physics Department, McGill University, Montreal, QC H3A 2T8 (Canada); Arlen, T. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States); Aune, T.; Bouvier, A. [Santa Cruz Institute for Particle Physics and Department of Physics, University of California, Santa Cruz, CA 95064 (United States); Beilicke, M.; Buckley, J. H.; Bugaev, V.; Dickherber, R. [Department of Physics, Washington University, St. Louis, MO 63130 (United States); Benbow, W. [Fred Lawrence Whipple Observatory, Harvard-Smithsonian Center for Astrophysics, Amado, AZ 85645 (United States); Cesarini, A.; Connolly, M. P. [School of Physics, National University of Ireland Galway, University Road, Galway (Ireland); Ciupik, L. [Astronomy Department, Adler Planetarium and Astronomy Museum, Chicago, IL 60605 (United States); Collins-Hughes, E. [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Cui, W. [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States); Duke, C. [Department of Physics, Grinnell College, Grinnell, IA 50112-1690 (United States); Dumm, J. [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Dwarkadas, V. V. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Falcone, A., E-mail: muk@astro.columbia.edu, E-mail: smcarthur@ulysses.uchicago.edu [Department of Astronomy and Astrophysics, 525 Davey Lab, Pennsylvania State University, University Park, PA 16802 (United States); and others

    2013-02-10

    We report the discovery of TeV gamma-ray emission coincident with the shell-type radio supernova remnant (SNR) CTA 1 using the VERITAS gamma-ray observatory. The source, VER J0006+729, was detected as a 6.5 standard deviation excess over background and shows an extended morphology, approximated by a two-dimensional Gaussian of semimajor (semiminor) axis 0. Degree-Sign 30 (0. Degree-Sign 24) and a centroid 5' from the Fermi gamma-ray pulsar PSR J0007+7303 and its X-ray pulsar wind nebula (PWN). The photon spectrum is well described by a power-law dN/dE = N {sub 0}(E/3 TeV){sup -{Gamma}}, with a differential spectral index of {Gamma} = 2.2 {+-} 0.2{sub stat} {+-} 0.3{sub sys}, and normalization N {sub 0} = (9.1 {+-} 1.3{sub stat} {+-} 1.7{sub sys}) Multiplication-Sign 10{sup -14} cm{sup -2} s{sup -1} TeV{sup -1}. The integral flux, F {sub {gamma}} = 4.0 Multiplication-Sign 10{sup -12} erg cm{sup -2} s{sup -1} above 1 TeV, corresponds to 0.2% of the pulsar spin-down power at 1.4 kpc. The energetics, colocation with the SNR, and the relatively small extent of the TeV emission strongly argue for the PWN origin of the TeV photons. We consider the origin of the TeV emission in CTA 1.

  10. Gamma-ray emission profile measurements during JET ICRH discharges

    Energy Technology Data Exchange (ETDEWEB)

    Jarvis, O N; Marcus, F B; Sadler, G; Van Belle, P [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Howarth, P J.A. [Birmingham Univ. (United Kingdom); Adams, J M; Bond, D S [UKAEA Harwell Lab. (United Kingdom). Energy Technology Div.

    1994-07-01

    Gamma-ray emission from plasma-impurity reactions caused by minority ICRH accelerating fuel ions to MeV energies has been measured using the JET neutron profile monitor. A successful data analysis technique has been used to isolate the RF-induced gamma-ray emission that was detected, enabling profiles of gamma-ray emission to be obtained. The 2-d gamma-ray emission profiles show that virtually all the radiation originates from the low field side of the RF resonance layer, as expected from RF-induced pitch angle diffusion. The emission profiles indicate the presence of a small population of resonant {sup 3}He ions that possess orbits lying near the passing-trapped boundary. 6 refs., 4 figs.

  11. MCNP modelling of scintillation-detector gamma-ray spectra from natural radionuclides.

    Science.gov (United States)

    Hendriks, P H G M; Maucec, M; de Meijer, R J

    2002-09-01

    gamma-ray spectra of natural radionuclides are simulated for a BGO detector in a borehole geometry using the Monte Carlo code MCNP. All gamma-ray emissions of the decay of 40K and the series of 232Th and 238U are used to describe the source. A procedure is proposed which excludes the time-consuming electron tracking in less relevant areas of the geometry. The simulated gamma-ray spectra are benchmarked against laboratory data.

  12. Gamma-ray emission from internal shocks in novae

    Science.gov (United States)

    Martin, P.; Dubus, G.; Jean, P.; Tatischeff, V.; Dosne, C.

    2018-04-01

    Context. Gamma-ray emission at energies ≥100 MeV has been detected from nine novae using the Fermi Large Area Telescope (LAT), and can be explained by particle acceleration at shocks in these systems. Eight out of these nine objects are classical novae in which interaction of the ejecta with a tenuous circumbinary material is not expected to generate detectable gamma-ray emission. Aim. We examine whether particle acceleration at internal shocks can account for the gamma-ray emission from these novae. The shocks result from the interaction of a fast wind radiatively-driven by nuclear burning on the white dwarf with material ejected in the initial runaway stage of the nova outburst. Methods: We present a one-dimensional model for the dynamics of a forward and reverse shock system in a nova ejecta, and for the associated time-dependent particle acceleration and high-energy gamma-ray emission. Non-thermal proton and electron spectra are calculated by solving a time-dependent transport equation for particle injection, acceleration, losses, and escape from the shock region. The predicted emission is compared to LAT observations of V407 Cyg, V1324 Sco, V959 Mon, V339 Del, V1369 Cen, and V5668 Sgr. Results: The ≥100 MeV gamma-ray emission arises predominantly from particles accelerated up to 100 GeV at the reverse shock and undergoing hadronic interactions in the dense cooling layer downstream of the shock. The emission rises within days after the onset of the wind, quickly reaches a maximum, and its subsequent decrease reflects mostly the time evolution of the wind properties. Comparison to gamma-ray data points to a typical scenario where an ejecta of mass 10-5-10-4 M⊙ expands in a homologous way with a maximum velocity of 1000-2000 km s-1, followed within a day by a wind with a velocity values of which result in the majority of best-fit models having gamma-ray spectra with a high-energy turnover below 10 GeV. Our typical model is able to account for the main

  13. K and L X-ray emission intensities of some radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Verma, H R; Pal, D [Punjabi Univ., Patiala (India). Dept. of Physics

    1985-01-01

    The K and L x-ray emission intensities per 100 disintegrations have been calculated for some radionuclides using the latest adopted data for gamma-ray intensities, electron capture and internal conversion coefficients for the parent nuclides, fluorescence yield values, Coster-Kronig transition probabilities, average total number of primary L shell vacancies produced in the decay of K shell vacancies and emission rates for various shells and subshells for the daughter nuclei. The results are in good agreement with theoretical and experimental values for the K x-ray intensities. There are no experimental results available to compare with the present calculations for the L x-ray intensities; however, there is a marked discrepancy in the L..cap alpha.. and L..beta.. intensities available on the basis of theoretical estimates.

  14. Energy spectrum of lightning gamma emission

    Energy Technology Data Exchange (ETDEWEB)

    Chubenko, A.P. [P.N. Lebedev Physical Institute of RAS, Moscow (Russian Federation); Karashtin, A.N. [Research Radiophysics Institute, Nizhny Novgorod (Russian Federation); Ryabov, V.A., E-mail: ryabov@x4u.lebedev.r [P.N. Lebedev Physical Institute of RAS, Moscow (Russian Federation); Shepetov, A.L. [P.N. Lebedev Physical Institute of RAS, Moscow (Russian Federation); Antonova, V.P.; Kryukov, S.V. [Ionosphere Institute, Almaty (Kazakhstan); Mitko, G.G.; Naumov, A.S.; Pavljuchenko, L.V. [P.N. Lebedev Physical Institute of RAS, Moscow (Russian Federation); Ptitsyn, M.O., E-mail: ptitsyn@lpi.r [P.N. Lebedev Physical Institute of RAS, Moscow (Russian Federation); Shalamova, S.Ya. [P.N. Lebedev Physical Institute of RAS, Moscow (Russian Federation); Shlyugaev, Yu.V. [Research Radiophysics Institute, Nizhny Novgorod (Russian Federation); Vildanova, L.I. [Tien-Shan Mountain Cosmic Ray Station, Almaty (Kazakhstan); Zybin, K.P. [P.N. Lebedev Physical Institute of RAS, Moscow (Russian Federation); Gurevich, A.V., E-mail: alex@lpi.r [P.N. Lebedev Physical Institute of RAS, Moscow (Russian Federation)

    2009-08-10

    The results of gamma emission observations obtained during thunderstorms at Tien-Shan Mountain Cosmic Ray Station are presented. The energy spectrum radiation of the stepped leader gamma radiation is measured. The total energy of stepped leader emitted in gamma rays is estimated as 10{sup -3}-10{sup -2} J. The experimental results are in an agreement with the runaway breakdown mechanism.

  15. Energy spectrum of lightning gamma emission

    International Nuclear Information System (INIS)

    Chubenko, A.P.; Karashtin, A.N.; Ryabov, V.A.; Shepetov, A.L.; Antonova, V.P.; Kryukov, S.V.; Mitko, G.G.; Naumov, A.S.; Pavljuchenko, L.V.; Ptitsyn, M.O.; Shalamova, S.Ya.; Shlyugaev, Yu.V.; Vildanova, L.I.; Zybin, K.P.; Gurevich, A.V.

    2009-01-01

    The results of gamma emission observations obtained during thunderstorms at Tien-Shan Mountain Cosmic Ray Station are presented. The energy spectrum radiation of the stepped leader gamma radiation is measured. The total energy of stepped leader emitted in gamma rays is estimated as 10 -3 -10 -2 J. The experimental results are in an agreement with the runaway breakdown mechanism.

  16. OBSERVATION OF CORRELATED OPTICAL AND GAMMA EMISSIONS FROM GRB 081126

    International Nuclear Information System (INIS)

    Klotz, A.; Boer, M.; Gendre, B.; Atteia, J. L.; Coward, D. M.; Imerito, A. C.

    2009-01-01

    We present an analysis of time-resolved optical emissions observed from the gamma-ray burst GRB 081126 during the prompt phase. The analysis employed time-resolved photometry using optical data obtained by the TAROT telescope, using BAT data from the Swift spacecraft, and time-resolved spectroscopy at high energies from the GBM instrument onboard the Fermi spacecraft. The optical emission of GRB 081126 is found to be compatible with the second gamma emission pulse shifted by a positive time lag of 8.4 ± 3.9 s. This is the first well-resolved observation of a time lag between optical and gamma emissions during a gamma-ray burst. Our observations could potentially provide new constraints on the fireball model for gamma-ray burst early emissions. Furthermore, observations of time lags between optical and gamma ray photons provides an exciting opportunity to constrain quantum gravity theories.

  17. A Correlated Optical and Gamma Emission from GRB 081126A

    International Nuclear Information System (INIS)

    Gendre, B.; Klotz, A.; Atteia, J. L.; Boeer, M.; Coward, D. M.; Imerito, A. C.

    2010-01-01

    We present an analysis of time-resolved optical emissions observed from the gamma-ray burst GRB 081126 during the prompt phase. The analysis employed time-resolved photometry using optical data obtained by the TAROT telescope, BAT data from the Swift spacecraft and time-resolved spectroscopy at high energies from the GBM instrument onboard the Fermi spacecraft. The optical emission of GRB 081126 is found to be compatible with the second gamma emission pulse shifted by a positive time-lag of 8.4±3.9 sec. This is the first well resolved observation of a time lag between optical and gamma emissions during a gamma-ray burst. Our observations could potentially provide new constraints on the fireball model for gamma ray burst early emissions. Furthermore, observations of time-lags between optical and gamma ray photons provides an exciting opportunity to constrain quantum gravity theories.

  18. Simulating Gamma-Ray Emission in Star-forming Galaxies

    Energy Technology Data Exchange (ETDEWEB)

    Pfrommer, Christoph [Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, D-14482 Potsdam (Germany); Pakmor, Rüdiger; Simpson, Christine M.; Springel, Volker, E-mail: cpfrommer@aip.de [Heidelberg Institute for Theoretical Studies, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany)

    2017-10-01

    Star-forming galaxies emit GeV and TeV gamma-rays that are thought to originate from hadronic interactions of cosmic-ray (CR) nuclei with the interstellar medium. To understand the emission, we have used the moving-mesh code Arepo to perform magnetohydrodynamical galaxy formation simulations with self-consistent CR physics. Our galaxy models exhibit a first burst of star formation that injects CRs at supernovae. Once CRs have sufficiently accumulated in our Milky Way–like galaxy, their buoyancy force overcomes the magnetic tension of the toroidal disk field. As field lines open up, they enable anisotropically diffusing CRs to escape into the halo and to accelerate a bubble-like, CR-dominated outflow. However, these bubbles are invisible in our simulated gamma-ray maps of hadronic pion-decay and secondary inverse-Compton emission because of low gas density in the outflows. By adopting a phenomenological relation between star formation rate (SFR) and far-infrared emission and assuming that gamma-rays mainly originate from decaying pions, our simulated galaxies can reproduce the observed tight relation between far-infrared and gamma-ray emission, independent of whether we account for anisotropic CR diffusion. This demonstrates that uncertainties in modeling active CR transport processes only play a minor role in predicting gamma-ray emission from galaxies. We find that in starbursts, most of the CR energy is “calorimetrically” lost to hadronic interactions. In contrast, the gamma-ray emission deviates from this calorimetric property at low SFRs due to adiabatic losses, which cannot be identified in traditional one-zone models.

  19. Simulating Gamma-Ray Emission in Star-forming Galaxies

    Science.gov (United States)

    Pfrommer, Christoph; Pakmor, Rüdiger; Simpson, Christine M.; Springel, Volker

    2017-10-01

    Star-forming galaxies emit GeV and TeV gamma-rays that are thought to originate from hadronic interactions of cosmic-ray (CR) nuclei with the interstellar medium. To understand the emission, we have used the moving-mesh code Arepo to perform magnetohydrodynamical galaxy formation simulations with self-consistent CR physics. Our galaxy models exhibit a first burst of star formation that injects CRs at supernovae. Once CRs have sufficiently accumulated in our Milky Way-like galaxy, their buoyancy force overcomes the magnetic tension of the toroidal disk field. As field lines open up, they enable anisotropically diffusing CRs to escape into the halo and to accelerate a bubble-like, CR-dominated outflow. However, these bubbles are invisible in our simulated gamma-ray maps of hadronic pion-decay and secondary inverse-Compton emission because of low gas density in the outflows. By adopting a phenomenological relation between star formation rate (SFR) and far-infrared emission and assuming that gamma-rays mainly originate from decaying pions, our simulated galaxies can reproduce the observed tight relation between far-infrared and gamma-ray emission, independent of whether we account for anisotropic CR diffusion. This demonstrates that uncertainties in modeling active CR transport processes only play a minor role in predicting gamma-ray emission from galaxies. We find that in starbursts, most of the CR energy is “calorimetrically” lost to hadronic interactions. In contrast, the gamma-ray emission deviates from this calorimetric property at low SFRs due to adiabatic losses, which cannot be identified in traditional one-zone models.

  20. Accumulation of 137Cs and 40K in aboveground organs of tropical woody fruit plants

    International Nuclear Information System (INIS)

    Anjos, R.M.; Sanches, N.; Macario, K.D.; Rizzotto, M.; Velasco, H.; Valladares, D.L.

    2009-01-01

    Distribution of 40 K and 137 Cs in tissues of the Citrus aurantifolia was measured by gamma spectrometry. A simple theoretical model is also proposed to describe the temporal evolution of 40 K activity concentration in such tropical woody fruit species. This model exhibits close agreement with the 40 K experimental results, in the leaf growing and fruit ripening processes of lemon trees. (author)

  1. Gamma-ray pulsars: Emission zones and viewing geometries

    Science.gov (United States)

    Romani, Roger W.; Yadigaroglu, I.-A.

    1995-01-01

    There are now a half-dozen young pulsars detected in high-energy photons by the Compton Gamma-Ray Observatory (CGRO), showing a variety of emission efficiencies and pulse profiles. We present here a calculation of the pattern of high-energy emission on the sky in a model which posits gamma-ray production by charge-depleted gaps in the outer magnetosphere. This model accounts for the radio to gamma-ray pulse offsets of the known pulsars, as well as the shape of the high-energy pulse profiles. We also show that about one-third of emitting young radio pulsars will not be detected due to beaming effects, while approximately 2.5 times the number of radio-selected gamma-ray pulsars will be viewed only high energies. Finally we compute the polarization angle variation and find that the previously misunderstood optical polarization sweep of the Crab pulsar arises naturally in this picture. These results strongly support an outer magnetosphere location for the gamma-ray emission.

  2. Gamma-emissions of some meteorites and terrestrial rocks. Evaluation of lunar soil radioactivity; Emissions gamma de quelques meteorites et roches terrestres. Evaluation de la radioactivite du sol lunaire

    Energy Technology Data Exchange (ETDEWEB)

    Nordemann, D. [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

    1966-07-01

    The gamma-emissions of some terrestrial rocks and of the following meteorites: Bogou, Eagle-Station, Granes, and Dosso were studied by quantitative low background gamma spectrometry. These measurements and their interpretation lead to the evaluation of the possible gamma-emissions of several models of lunar soils. (author) [French] Les emissions gamma des meteorites Bogou, Eagle-Station, Granes et Dosso et de quelques roches terrestres ont ete etudiees par spectrometrie gamma quantitative a faible mouvement propre. Ces mesures et leur interpretation permettent d'evaluer les principales contributions des emissions gamma du sol lunaire pour des modeles de compositions possibles variees. (auteur)

  3. Gamma-emissions of some meteorites and terrestrial rocks. Evaluation of lunar soil radioactivity; Emissions gamma de quelques meteorites et roches terrestres. Evaluation de la radioactivite du sol lunaire

    Energy Technology Data Exchange (ETDEWEB)

    Nordemann, D [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

    1966-07-01

    The gamma-emissions of some terrestrial rocks and of the following meteorites: Bogou, Eagle-Station, Granes, and Dosso were studied by quantitative low background gamma spectrometry. These measurements and their interpretation lead to the evaluation of the possible gamma-emissions of several models of lunar soils. (author) [French] Les emissions gamma des meteorites Bogou, Eagle-Station, Granes et Dosso et de quelques roches terrestres ont ete etudiees par spectrometrie gamma quantitative a faible mouvement propre. Ces mesures et leur interpretation permettent d'evaluer les principales contributions des emissions gamma du sol lunaire pour des modeles de compositions possibles variees. (auteur)

  4. Determination of {sup 40}K in water samples; Determinacion del {sup 40}K en muestras de agua

    Energy Technology Data Exchange (ETDEWEB)

    Delgado, C. E.; Miranda C, L.; Cuevas J, A. K.; Vega C, H. R., E-mail: rmfranccesco0223@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2014-10-15

    The natural water used for human consumption comes from different sources, which may contain suspended solids in varying proportions. In groundwater, the source of suspended solids is related to the dissolution of mineral strata by the waters and leaching of rocks. Also, the radioactivity could concentrate on the bodies of slow-moving water that eventually could present a risk to ecosystems, as well as for the consumer. The water usually contains several natural radionuclides as: tritium, radon, radio, uranium isotopes, etc. The objective of this study was to evaluate the concentration of {sup 40}K in water from different areas of Zacatecas state (Mexico). Four water samples were taken in triplicate from different areas; the {sup 40}K concentration was measured with a spectrum metric system of gamma radiation with NaI (Tl) scintillation detector of 7.62 cm. In the measuring process a standard was prepared using water and KCl analytic grade where the {sup 40}K concentration is 6.25 mol/Lt adding 250 mg/ml of potassium. Also the system was calibrated in energy using 3 point sources of {sup 137}Cs, diameter {sup 22}Na and 7.62 cm of height, using containers Marinelli and {sup 60}Co. In the obtained spectra was observed that the photon of 1.432 MeV that emits the {sup 40}K when decaying is the most important. The highest concentration was of 123 ± 5.2 Bq/lt and the lowest was of 9 ± 0.4 Bq/lt. Under the standards of drinking water, an amount of {sup 40}K deposits an effective dose which contributes to annual dose received by people. (Author)

  5. /sup 137/Cs and /sup 40/K levels in marine species caught in Malaysian waters

    Energy Technology Data Exchange (ETDEWEB)

    Dougherty, G.; Ng, C.E. (Universiti Sains Malaysia, Penang (Malaysia). School of Physics)

    1982-12-01

    Activity levels of /sup 137/Cs and /sup 40/K in a variety of marine species caught in the Indian Ocean and S. China Seas, between Jan. 1980 - Sept. 1981, have been monitored, using gamma spectroscopy. Samples were dried to constant weight, powdered, and a constant volume used for gamma spectroscopy. Radioactivity levels and concentration factors for /sup 40/K and /sup 137/Cs are presented. /sup 137/Cs concentration factors are found to vary greatly between species caught in the same area, possibly due to different feeding patterns and levels.

  6. Assessment of Geant4 Prompt-Gamma Emission Yields in the Context of Proton Therapy Monitoring

    Science.gov (United States)

    Pinto, Marco; Dauvergne, Denis; Freud, Nicolas; Krimmer, Jochen; Létang, Jean M.; Testa, Etienne

    2016-01-01

    Monte Carlo tools have been long used to assist the research and development of solutions for proton therapy monitoring. The present work focuses on the prompt-gamma emission yields by comparing experimental data with the outcomes of the current version of Geant4 using all applicable proton inelastic models. For the case in study and using the binary cascade model, it was found that Geant4 overestimates the prompt-gamma emission yields by 40.2 ± 0.3%, even though it predicts the prompt-gamma profile length of the experimental profile accurately. In addition, the default implementations of all proton inelastic models show an overestimation in the number of prompt gammas emitted. Finally, a set of built-in options and physically sound Geant4 source code changes have been tested in order to try to improve the discrepancy observed. A satisfactory agreement was found when using the QMD model with a wave packet width equal to 1.3 fm2. PMID:26858937

  7. GRB 090727 AND GAMMA-RAY BURSTS WITH EARLY-TIME OPTICAL EMISSION

    International Nuclear Information System (INIS)

    Kopač, D.; Gomboc, A.; Japelj, J.; Kobayashi, S.; Mundell, C. G.; Bersier, D.; Cano, Z.; Smith, R. J.; Steele, I. A.; Virgili, F. J.; Guidorzi, C.; Melandri, A.

    2013-01-01

    We present a multi-wavelength analysis of Swift gamma-ray burst GRB 090727, for which optical emission was detected during the prompt gamma-ray emission by the 2 m autonomous robotic Liverpool Telescope and subsequently monitored for a further two days with the Liverpool and Faulkes Telescopes. Within the context of the standard fireball model, we rule out a reverse shock origin for the early-time optical emission in GRB 090727 and instead conclude that the early-time optical flash likely corresponds to emission from an internal dissipation process. Putting GRB 090727 into a broader observational and theoretical context, we build a sample of 36 gamma-ray bursts (GRBs) with contemporaneous early-time optical and gamma-ray detections. From these GRBs, we extract a sub-sample of 18 GRBs, which show optical peaks during prompt gamma-ray emission, and perform detailed temporal and spectral analysis in gamma-ray, X-ray, and optical bands. We find that in most cases early-time optical emission shows sharp and steep behavior, and notice a rich diversity of spectral properties. Using a simple internal shock dissipation model, we show that the emission during prompt GRB phase can occur at very different frequencies via synchrotron radiation. Based on the results obtained from observations and simulation, we conclude that the standard external shock interpretation for early-time optical emission is disfavored in most cases due to sharp peaks (Δt/t < 1) and steep rise/decay indices, and that internal dissipation can explain the properties of GRBs with optical peaks during gamma-ray emission

  8. Soft x-ray emission from gamma-ray bursts observed with ginga

    International Nuclear Information System (INIS)

    Yoshida, Atsumasa; Murakami, Toshio; Itoh, Masayuki

    1989-01-01

    The soft X-ray emission of gamma-ray bursts below 10 keV provides information about size, location, and emission mechanism. The Gamma-ray Burst Detector (GBD) on board Ginga, which consists of a proportional counter and a scintillation detector, covers an energy range down to 1.5 keV with 63 cm 2 effective area. In several of the observed gamma-ray bursts, the intensity of the soft X-ray emission showed a longer decay time of 50 to 100s after the higher energy gamma-ray emission had ended. Although we cannot rule out other models, such as bremsstrahlung and thermal cyclotron types, due to poor statistics, the soft X-ray spectra are consistent with a blackbody of 1 to 2 keV in the late phase of the gamma-ray bursts. This enables us to estimate the size of the blackbody responsible for the X-ray emission. (author)

  9. Gamma-ray Emission from Globular Clusters

    Directory of Open Access Journals (Sweden)

    Pak-Hin T. Tam

    2016-03-01

    Full Text Available Over the last few years, the data obtained using the Large Area Telescope (LAT aboard the Fermi Gamma-ray Space Telescope has provided new insights on high-energy processes in globular clusters, particularly those involving compact objects such as MilliSecond Pulsars (MSPs. Gamma-ray emission in the 100 MeV to 10 GeV range has been detected from more than a dozen globular clusters in our galaxy, including 47 Tucanae and Terzan 5. Based on a sample of known gammaray globular clusters, the empirical relations between gamma-ray luminosity and properties of globular clusters such as their stellar encounter rate, metallicity, and possible optical and infrared photon energy densities, have been derived. The measured gamma-ray spectra are generally described by a power law with a cut-off at a few gigaelectronvolts. Together with the detection of pulsed γ-rays from two MSPs in two different globular clusters, such spectral signature lends support to the hypothesis that γ-rays from globular clusters represent collective curvature emission from magnetospheres of MSPs in the clusters. Alternative models, involving Inverse-Compton (IC emission of relativistic electrons that are accelerated close to MSPs or pulsar wind nebula shocks, have also been suggested. Observations at >100 GeV by using Fermi/LAT and atmospheric Cherenkov telescopes such as H.E.S.S.-II, MAGIC-II, VERITAS, and CTA will help to settle some questions unanswered by current data.

  10. 40 K, 137 Cs and 232 Th activities in Brazilian milk samples measured by gamma ray spectrometry

    International Nuclear Information System (INIS)

    Melquiades, Fabio L.; Appoloni, Carlos R.

    2000-01-01

    This work deals with the measurement of radioactive activities in powdered milk, with high resolution gamma-ray spectrometry, using a HPGe detector coupled to a standard electronic nuclear chain and a multichannel card of 8192 channels. Preliminary measurements were accomplished to define the kind of the system shield, the geometry of the sample recipient, the size of the sampling and the self absorption correction. It was possible to measure the radionuclides 40 K, 137 Cs and 208 Tl, whose activities were calculated according to the International Atomic Energy Agency norms. The detector efficiency was measured employing calibrated samples, prepared with IAEA certificate standards mixed with powdered milk. Tukey's average comparison test was used to check the repeatability of the measurements and the absence of significant systematic deviation. (author)

  11. Determination of 40K in water samples

    International Nuclear Information System (INIS)

    Delgado, C. E.; Miranda C, L.; Cuevas J, A. K.; Vega C, H. R.

    2014-10-01

    The natural water used for human consumption comes from different sources, which may contain suspended solids in varying proportions. In groundwater, the source of suspended solids is related to the dissolution of mineral strata by the waters and leaching of rocks. Also, the radioactivity could concentrate on the bodies of slow-moving water that eventually could present a risk to ecosystems, as well as for the consumer. The water usually contains several natural radionuclides as: tritium, radon, radio, uranium isotopes, etc. The objective of this study was to evaluate the concentration of 40 K in water from different areas of Zacatecas state (Mexico). Four water samples were taken in triplicate from different areas; the 40 K concentration was measured with a spectrum metric system of gamma radiation with NaI (Tl) scintillation detector of 7.62 cm. In the measuring process a standard was prepared using water and KCl analytic grade where the 40 K concentration is 6.25 mol/Lt adding 250 mg/ml of potassium. Also the system was calibrated in energy using 3 point sources of 137 Cs, diameter 22 Na and 7.62 cm of height, using containers Marinelli and 60 Co. In the obtained spectra was observed that the photon of 1.432 MeV that emits the 40 K when decaying is the most important. The highest concentration was of 123 ± 5.2 Bq/lt and the lowest was of 9 ± 0.4 Bq/lt. Under the standards of drinking water, an amount of 40 K deposits an effective dose which contributes to annual dose received by people. (Author)

  12. Gravitational Waves versus X and Gamma Ray Emission in a Short Gamma-Ray Burst

    OpenAIRE

    Oliveira, F. G.; Rueda, Jorge A.; Ruffini, Remo

    2012-01-01

    The recent progress in the understanding the physical nature of neutron star equilibrium configurations and the first observational evidence of a genuinely short gamma-ray burst, GRB 090227B, allows to give an estimate of the gravitational waves versus the X and Gamma-ray emission in a short gamma-ray burst.

  13. The measurement of activities of 226Ra, 232Th, 40K in phosphogypsum by gamma ray spectrometry

    International Nuclear Information System (INIS)

    Parmaksiz, A.

    2004-06-01

    Phosphatic fertilizers are produced from the industrial processing of rock phosphate ores which are known to contain naturally occuring radionuclides such as 238 U and its daughter products. A high volume by-product known as phosphogypsum (PG) from the production of phosphoric acid and phosphate fertilizer causes serious storage and environmental problems in phosphoric acid industries. During the phosphoric acid production process, 226 Ra (t 1/2 =1600 y) ends up in PG which has chemical analogous to calcium periodical table. Since the stockpiles of PG near the phosphatic fertilizer plants are huge amounts, the radioactivity contained in PG has to measured in view of environmental radioactivity problem. In this work, the natural radioactivity in eighty PG samples, issued from a stock of about 60.000 tones was measured by a high resolution gamma ray spectrometer with a HPGe detector. The averaged activity of 226 Ra in PG has been found to be 546 Bq.kg -1 . However, the activities of 232 Th and 40 K measured in PG samples are negligibly small. The extra gamma radiation dose rate arising from 1 - 1.5 kg of PG is estimated to be about 241 nGy/h from 1 m ground level applied in 1 m 2 surface area of field

  14. On k-Gamma and k-Beta Distributions and Moment Generating Functions

    Directory of Open Access Journals (Sweden)

    Gauhar Rahman

    2014-01-01

    Full Text Available The main objective of the present paper is to define k-gamma and k-beta distributions and moments generating function for the said distributions in terms of a new parameter k>0. Also, the authors prove some properties of these newly defined distributions.

  15. Direct transitions from high-K isomers to low-K bands -- {gamma} softness or coriolis coupling

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Yoshifumi R.; Narimatsu, Kanako; Ohtsubo, Shin-Ichi [Kyushu Univ., Fukuoka (Japan)] [and others

    1996-12-31

    Recent measurements of direct transitions from high-K isomers to low-K bands reveal severe break-down of the K-selection rule and pose the problem of how to understand the mechanism of such K-violation. The authors recent systematic calculations by using a simple {gamma}-tunneling model reproduced many of the observed hindrances, indicating the importance of the {gamma} softness. However, there are some data which cannot be explained in terms of the {gamma}-degree of freedom. In this talk, the authors also discuss the results of conventional Coriolis coupling calculations, which is considered to be another important mechanism.

  16. Study of the $K^{\\pm} \\rightarrow \\pi^{\\pm} \\gamma \\gamma$ decay by the NA62 experiment

    CERN Document Server

    INSPIRE-00100355; Romano, A.; Ceccucci, A.; Danielsson, H.; Falaleev, V.; Gatignon, L.; Goy Lopez, S.; Hallgren, B.; Maier, A.; Peters, A.; Piccini, M.; Riedler, P.; Frabetti, P.L.; Gersabeck, E.; Kekelidze, V.; Madigozhin, D.; Misheva, M.; Molokanova, N.; Movchan, S.; Shkarovskiy, S.; Zinchenko, A.; Rubin, P.; Baldini, W.; Cotta Ramusino, A.; Dalpiaz, P.; Fiorini, M.; Gianoli, A.; Norton, A.; Petrucci, F.; Savrie, M.; Wahl, H.; Bizzeti, A.; Bucci, F.; Iacopini, E.; Lenti, M.; Veltri, M.; Antonelli, A.; Moulson, M.; Raggi, M.; Spadaro, T.; Eppard, K.; Hita-Hochgesand, M.; Kleinknecht, K.; Renk, B.; Wanke, R.; Winhart, A.; Winston, R.; Bolotov, V.; Duk, V.; Gushchin, E.; Ambrosino, F.; Di Filippo, D.; Massarotti, P.; Napolitano, M.; Palladino, V.; Saracino, G.; Anzivino, G.; Imbergamo, E.; Piandani, R.; Sergi, A.; Cenci, P.; Pepe, M.; Costantini, F.; Doble, N.; Giudici, S.; Pierazzini, G.; Sozzi, M.; Venditti, S.; Balev, S.; Collazuol, G.; Di, L.; Gallorini, S.; Goudzovski, E.; Lamanna, G.; Mannelli, I.; Ruggiero, G.; Cerri, C.; Fantechi, R.; Kholodenko, S.; Kurshetsov, V.; Obraztsov, V.; Semenov, V.; Yushchenko, O.; D'Agostini, G.; Leonardi, E.; Serra, M.; Valente, P.; Fucci, A.; Salamon, A.; Bloch-Devaux, B.; Peyaud, B.; Engelfried, J.; Coward, D.; Kozhuharov, V.; Litov, L.; Arcidiacono, R.; Bifani, S.; Biino, C.; Dellacasa, G.; Marchetto, F.; Numao, T.; Retiere, F.

    2014-05-01

    A study of the dynamics of the rare decay $K^\\pm\\to\\pi^\\pm\\gamma\\gamma$ has been performed on a sample of 232 decay candidates, with an estimated background of $17.4\\pm1.1$ events, collected by the NA62 experiment at CERN in 2007. The results are combined with those from a measurement conducted by the NA48/2 collaboration at CERN. The combined model-independent branching ratio in the kinematic range $z=(m_{\\gamma\\gamma}/m_K)^2>0.2$ is ${\\cal B}_{\\rm MI}(z>0.2) = (0.965 \\pm 0.063) \\times 10^{-6}$, and the combined branching ratio in the full kinematic range assuming a Chiral Perturbation Theory description is ${\\cal B}(K_{\\pi\\gamma\\gamma}) = (1.003 \\pm 0.056) \\times 10^{-6}$. A detailed comparison of the results with the previous measurements is performed.

  17. Neutrino emission from gamma-ray burst fireballs, revised.

    Science.gov (United States)

    Hümmer, Svenja; Baerwald, Philipp; Winter, Walter

    2012-06-08

    We review the neutrino flux from gamma-ray bursts, which is estimated from gamma-ray observations and used for the interpretation of recent IceCube data, from a particle physics perspective. We numerically calculate the neutrino flux for the same astrophysical assumptions as the analytical fireball neutrino model, including the dominant pion and kaon production modes, flavor mixing, and magnetic field effects on the secondary muons, pions, and kaons. We demonstrate that taking into account the full energy dependencies of all spectra, the normalization of the expected neutrino flux reduces by about one order of magnitude and the spectrum shifts to higher energies, where we can pin down the exact origin of the discrepancies by the recomputation of the analytical models. We also reproduce the IceCube-40 analysis for exactly the same bursts and same assumptions and illustrate the impact of uncertainties. We conclude that the baryonic loading of the fireballs, which is an important control parameter for the emission of cosmic rays, can be constrained significantly with the full-scale experiment after about ten years.

  18. Polarization of the prompt gamma-ray emission from the gamma-ray burst of 6 December 2002.

    Science.gov (United States)

    Coburn, Wayne; Boggs, Steven E

    2003-05-22

    Observations of the afterglows of gamma-ray bursts (GRBs) have revealed that they lie at cosmological distances, and so correspond to the release of an enormous amount of energy. The nature of the central engine that powers these events and the prompt gamma-ray emission mechanism itself remain enigmatic because, once a relativistic fireball is created, the physics of the afterglow is insensitive to the nature of the progenitor. Here we report the discovery of linear polarization in the prompt gamma-ray emission from GRB021206, which indicates that it is synchrotron emission from relativistic electrons in a strong magnetic field. The polarization is at the theoretical maximum, which requires a uniform, large-scale magnetic field over the gamma-ray emission region. A large-scale magnetic field constrains possible progenitors to those either having or producing organized fields. We suggest that the large magnetic energy densities in the progenitor environment (comparable to the kinetic energy densities of the fireball), combined with the large-scale structure of the field, indicate that magnetic fields drive the GRB explosion.

  19. Gamma-Ray Emission from Galaxy Clusters : DARK MATTER AND COSMIC-RAYS

    Science.gov (United States)

    Pinzke, Anders

    The quest for the first detection of a galaxy cluster in the high energy gamma-ray regime is ongoing, and even though clusters are observed in several other wave-bands, there is still no firm detection in gamma-rays. To complement the observational efforts we estimate the gamma-ray contributions from both annihilating dark matter and cosmic-ray (CR) proton as well as CR electron induced emission. Using high-resolution simulations of galaxy clusters, we find a universal concave shaped CR proton spectrum independent of the simulated galaxy cluster. Specifically, the gamma-ray spectra from decaying neutral pions, which are produced by CR protons, dominate the cluster emission. Furthermore, based on our derived flux and luminosity functions, we identify the galaxy clusters with the brightest galaxy clusters in gamma-rays. While this emission is challenging to detect using the Fermi satellite, major observations with Cherenkov telescopes in the near future may put important constraints on the CR physics in clusters. To extend these predictions, we use a dark matter model that fits the recent electron and positron data from Fermi, PAMELA, and H.E.S.S. with remarkable precision, and make predictions about the expected gamma-ray flux from nearby clusters. In order to remain consistent with the EGRET upper limit on the gamma-ray emission from Virgo, we constrain the minimum mass of substructures for cold dark matter halos. In addition, we find comparable levels of gamma-ray emission from CR interactions and dark matter annihilations without Sommerfeld enhancement.

  20. $\\gamma$-Ray Pulsars: Emission Zones and Viewing Geometries

    OpenAIRE

    Romani, Roger W.; Yadigaroglu, I. -A.

    1994-01-01

    There are now a half dozen young pulsars detected in high energy photons by the Compton GRO, showing a variety of emission efficiencies and pulse profiles. We present here a calculation of the pattern of high energy emission on the sky in a model which posits $\\gamma$-ray production by charge depleted gaps in the outer magnetosphere. This model accounts for the radio to $\\gamma$-ray pulse offsets of the known pulsars, as well as the shape of the high energy pulse profiles. We also show that $...

  1. Search for the decay {phi}{yields}K{sup 0}K-bar {sup 0}{gamma} with the KLOE experiment

    Energy Technology Data Exchange (ETDEWEB)

    Ambrosino, F. [Dipartimento di Scienze Fisiche dell' Universita ' Federico II' , Napoli (Italy); INFN Sezione di Napoli, Napoli (Italy); Antonelli, A.; Antonelli, M. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Archilli, F. [Dipartimento di Fisica dell' Universita ' Tor Vergata' , Roma (Italy); INFN Sezione Roma Tor Vergata, Roma (Italy); Beltrame, P. [Institut fuer Kernphysik, Johannes Gutenberg, Universitaet Mainz (Germany); Bencivenni, G.; Bertolucci, S. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Bini, C. [Dipartimento di Fisica dell' Universita Sapienza di Roma, Roma (Italy); INFN Sezione di Roma, Roma (Italy); Bloise, C. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Bocchetta, S. [Dipartimento di Fisica dell' Universita ' Roma Tre' , Roma (Italy); INFN Sezione Roma Tre, Roma (Italy); Bossi, F. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Branchini, P. [INFN Sezione Roma Tre, Roma (Italy); Capon, G.; Capussela, T. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); Ceradini, F. [Dipartimento di Fisica dell' Universita ' Roma Tre' , Roma (Italy); INFN Sezione Roma Tre, Roma (Italy); Ciambrone, P.; De Lucia, E. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); De Santis, A. [Dipartimento di Fisica dell' Universita Sapienza di Roma, Roma (Italy); INFN Sezione di Roma, Roma (Italy); De Simone, P. [Laboratori Nazionali di Frascati dell' INFN, Frascati (Italy); De Zorzi, G. [Dipartimento di Fisica dell' Universita Sapienza di Roma, Roma (Italy); INFN Sezione di Roma, Roma (Italy)] (and others)

    2009-08-10

    We have searched for the decay {phi}{yields}K{sup 0}K-bar {sup 0}{gamma}, by detecting K{sub S} pairs plus a photon and with the K{sub S}-mesons decaying to {pi}{sup +}{pi}{sup -}, in a sample of about 1.5x10{sup 9}{phi}-decays collected by the KLOE experiment at DA{phi}NE. The reaction proceeds through the intermediate states f{sub 0}(980){gamma}, a{sub 0}(980){gamma}. We find five events with 3.2 events expected from background processes. We obtain the upper limit: BR({phi}{yields}K{sup 0}K-bar {sup 0}{gamma})<1.9x10{sup -8} at 90% CL.

  2. Limits for an inverse bremsstrahlung origin of the diffuse Galactic soft gamma-ray emission

    DEFF Research Database (Denmark)

    Pohl, M.

    1998-01-01

    origin of the soft Galactic gamma-ray continuum through inverse bremsstrahlung. A flux of low-energy cosmic rays strong enough to produce the observed spectrum of gamma-rays implies substantial gamma-ray emission at a few MeV through nuclear de-excitation. It is shown that the existing limits on excess 3......-7 MeV emission from the Galactic plane, in concert with the constraints from pi(0)-decay gamma-ray emission at higher energies, are in serious conflict with an inverse bremsstrahlung origin of the Galactic soft gamma-ray emission for any physically plausible low-energy cosmic ray spectrum. While...

  3. Two-quantum Doppler-free induced gamma emission

    International Nuclear Information System (INIS)

    Zadernovsky, A.A.

    1999-01-01

    Reported here is a theoretical study of an alternative way to remove the pernicious influence of chaotic motion of free nuclei by means of external ignition of two-quantum IGE process in counter-propagating intense photon beams. The performed analysis reveals the main advantages and drawbacks of this method. The following conclusions are underlined: 1. in contrast to single-quantum emission in an ensemble of nuclei with Doppler-broadened gain line, this method involves all nuclei regardless of there individual velocities; 2. a specific dynamic distributed feedback is in this case established in absence of any reflecting structures; 3. because of non-linearity of the feedback, with a coefficient proportional to the photon flux density of the igniting beam, the excitation of nuclei is released in an avalanche-like manner, which result in emission of a giant pulse of gamma quanta; 4. at present, the implementation of such a process is impeded by the absence of a source of igniting gamma quanta, with the sufficient photon flux density. Therefore the advantage of the propose technique may manifests themselves only in designing a final stage of a source of gamma quanta (e.g., in X-ray or gamma-ray laser, relativistic undulator, free electron laser, etc.) for production of short giant pulse of coherent gamma photons. (author)

  4. Dose due to 40K

    International Nuclear Information System (INIS)

    Escareno J, E.; Vega C, H. R.

    2011-10-01

    The dose due to 40 K has been estimated. Potassium is one of the most abundant elements in nature, being approximately 2% of the Earth's crust. Potassium has three isotopes 39 K, 40 K and 41 K, two are stable while 40 K is radioactive with a half life of 1.2x10 9 years; there is 0.0117% 40 K-to-K ratio. Potassium plays an important role in plants, animals and humans growth and reproduction. Due to the fact that K is an essential element for humans, 40 K is the most abundant radioisotope in human body. In order to keep good health conditions K must be intake at daily basis trough food and beverages, however when K in ingested above the requirements produce adverse health effects in persons with renal, cardiac and hypertension problems or suffering diabetes. In 89.3% 40 K decays to 40 C through β-decay, in 10.3% decays through electronic capture and emitting 1.46 MeV γ-ray. K is abundant in soil, construction materials, sand thus γ-rays produced during 40 K decay contribute to external dose. For K in the body practically all 40 K decaying energy is absorbed by the body; thus 40 K contributes to total dose in humans and it is important to evaluate its contribution. In this work a set of 40 K sources were prepared using different amounts of KCl salt, a γ-ray spectrometer with a NaI(Tl) was characterized to standardized the sources in order to evaluate the dose due to 40 K. Using thermoluminescent dosemeters the dose due to 40 K was measured and related to the amount of 40 K γ-ray activity. (Author)

  5. Multi-wavelength emission from 3C 66A: clues to its redshift and gamma-ray emission location

    International Nuclear Information System (INIS)

    Yan Da-Hai; Fan Zhong-Hui; Zhou Yao; Dai Ben-Zhong

    2013-01-01

    The quasi-simultaneous multi-wavelength emission of TeV blazar 3C 66A is studied by using a one-zone multi-component leptonic jet model. It is found that the quasi-simultaneous spectral energy distribution of 3C 66A can be well reproduced; in particular, the first three months of its average Fermi-LAT spectrum can be well reproduced by the synchrotron self-Compton component plus external Compton component of the broad line region (BLR). Clues to its redshift and gamma-ray emission location are obtained. The results indicate the following. (i) On the redshift: The theoretical intrinsic TeV spectra can be predicted by extrapolating the reproduced GeV spectra. Through comparing these extrapolated TeV spectra with the corrected observed TeV spectra from extragalactic background light, it is suggested that the redshift of 3C 66A could be between 0.1 and 0.3, with the most likely value being ∼ 0.2. (ii) On the gamma-ray emission location: To well reproduce the GeV emission of 3C 66A under different assumptions on the BLR, the gamma-ray emission region is always required to be beyond the inner zone of the BLR. The BLR absorption effect on gamma-ray emission confirms this point.

  6. The pulsar contribution to the diffuse galactic gamma-ray emission

    DEFF Research Database (Denmark)

    Pohl, M.; Kanbach, G.; Hunter, S.D.

    1997-01-01

    There is active interest in the extent to which unresolved gamma-ray pulsars contribute to the Galactic diffuse emission, and in whether unresolved gamma-ray pulsars could be responsible for the excess of diffuse Galactic emission above 1 GeV that has been observed by EGRET. The diffuse gamma......-ray intensity due to unresolved pulsars is directly linked to the number of objects that should be observed in the EGRET data. We can therefore use our knowledge of the unidentified EGRET sources to constrain model parameters like the pulsar birthrate and their beaming angle. This analysis is based only...... on the properties of the six pulsars that have been identified in the EGRET data and is independent of choice of a pulsar emission model. We find that pulsars contribute very little to the diffuse emission at lower energies, whereas above 1 GeV they can account for 18% of the observed intensity in selected regions...

  7. Gamma-emissions of some meteorites and terrestrial rocks. Evaluation of lunar soil radioactivity

    International Nuclear Information System (INIS)

    Nordemann, D.

    1966-01-01

    The gamma-emissions of some terrestrial rocks and of the following meteorites: Bogou, Eagle-Station, Granes, and Dosso were studied by quantitative low background gamma spectrometry. These measurements and their interpretation lead to the evaluation of the possible gamma-emissions of several models of lunar soils. (author) [fr

  8. Study of resonance formation in the mass region 1400 - 1500 MeV through the reaction $\\gamma\\gamma \\to K^{0}_{S} K^{\\pm} \\pi^{\\mp}$

    CERN Document Server

    Achard, P; Aguilar-Benítez, M; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Anderhub, H; Andreev, V P; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Bajo, A; Baksay, G; Baksay, L; Baldew, S V; Banerjee, S; Banerjee, Sw; Barczyk, A; Barillère, R; Bartalini, P; Basile, M; Batalova, N; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Bellucci, L; Berbeco, R; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Biasini, M; Biglietti, M; Biland, A; Blaising, J J; Blyth, S C; Bobbink, G J; Böhm, A; Boldizsar, L; Borgia, B; Bottai, S; Bourilkov, D; Bourquin, M; Braccini, S; Branson, J G; Brochu, F; Burger, J D; Burger, W J; Cai, X D; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A; Casaus, J; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada, M; Chamizo-Llatas, M; Chang, Y H; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chiefari, G; Cifarelli, L; Cindolo, F; Clare, I; Clare, R; Coignet, G; Colino, N; Costantini, S; Dela Cruz, B; Cucciarelli, S; De Asmundis, R; Deglon, P; Debreczeni, J; Degré, A; Dehmelt, K; Deiters, K; Della Volpe, D; Delmeire, E; Denes, P; De Notaristefani, F; De Salvo, A; Diemoz, M; Dierckxsens, M; Dionisi, C; Dittmar, M; Doria, A; Dova, M T; Duchesneau,; Duda, M; Echenard, B; Eline, A; El-Hage, A; El-Mamouni, H; Engler, A; Eppling, F J; Extermann, P; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, M; Ferguson, T; Fesefeldt, H; Fiandrini, E; Field, J H; Filthaut, F; Fisher, P H; Fisher, W; Forconi, G; Freudenreich, K; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gentile, S; Giagu, S; Gong, Z F; Grenier, G; Grimm, O; Grünewald, M W; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Hirschfelder, J; Hofer, H; Hohlmann, M; Holzner, G; Hou, S R; Jin, B N; Jindal, P; Jones, L W; de Jong, P; Josa-Mutuberria, I; Kaur, M; Kienzle-Focacci, M N; Kim, 0J K; Kirkby, Jasper; Kittel, W; Klimentov, A; König, A C; Kopal, M; Koutsenko, V; Kraber, M; Krämer, R W; Krüger, A; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Leiste, R; Levtchenko, M; Levchenko, P; Li, C; Likhoded, S; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lü, Y S; Luci, C; Luminari, L; Lustermann, W; Ma, W G; Malgeri, L; Malinin, A; Maña, C; Mans, J; Martin, J P; Marzano, F; Mazumdar, K; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Mihul, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Muanza, G S; Muijs, A J M; Musy, M; Nagy, S; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Nisati, A; Novák, T; Nowak, H; Ofierzynski, R; Organtini, G; Pal, I; Palomares, C; Paolucci, P; Paramatti, R; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, F; Pedace, M; Pensotti, S; Perret-Gallix, D; Piccolo, D; Pierella, F; Pieri, M; Pioppi, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Pothier, J; Prokofev, D; Prokofiev, D O; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A; Razis, P; Rembeczki, S; Ren, D; Rescigno, M; Reucroft, S; Riemann, S; Riles, K; Roe, B P; Romero, L; Rosca, A; Rosemann, C; Rosenbleck, C; Rosier-Lees, S; Roth, S; Rubio, J A; Ruggiero, G; Rykaczewski, H; Sakharov, A; Saremi, S; Sarkar, S; Salicio, J; Sánchez, E; Schäfer, C; Shchegelskii, V; Schopper, Herwig Franz; Schotanus, D J; Sciacca, C; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A; Son, D; Souga, C; Spillantini, P; Steuer, M; Stickland, D P; Stoyanov, B; Strässner, A; Sudhakar, K; Sultanov, G G; Sun, L Z; Sushkov, S; Suter, H; Swain, J D; Szillási, Z; Tang, X W; Tarjan, P; Tauscher, L; Taylor, L; Tellili, B; Teyssier, D; Timmermans, C; Ting, Samuel C C; Ting, S M; Tonwar, S C; Tóth, J; Tully, C; Tung, K L; Ulbricht, J; Valente, E; Van de Walle, R T; Wadhwa, M; Wang, Q; Wang, X L; Wang, Z M; Weber, M; Wynhoff, S; Xia, L; Xu, Z Z; Yamamoto, J; Yang, B Z; Yang, C G; Yang, H J; Yang, M; Yeh, S C; Zalite, A; Zalite, Yu; Zhang, Z P; Zhao, J; Zhu, G Y; Zhu, R Y; Zhuang, H L; Zichichi, A; Zimmermann, B; Zöller, M

    2007-01-01

    The K^0_SK^+-\\pi-+ final state in two-photon collisions is studied with the L3 detector at LEP at e+e- centre-of-mass energies from 183 to 209 GeV with an integrated luminosity of 664.6 pb-1. The \\eta(1475) and f1(1420) mesons are observed and their contribution is separated by measuring the formation rates as a function of the photon virtuality Q2. The \\eta(1475) is found to be dominant for Q2 <= 0.01GeV2 and its two-photon width is measured to be 0.23+-0.05 (stat.) +-0.05 (sys.) keV. At higher Q2, the f1(1420) is formed and decays to K(892)K. The \\gamma\\gamma coupling and form factor parameters of this state are measured to be \\Gamma\\gamma\\gamma = 3.2+-0.6 (stat.) +-0.7 (sys.) keV and \\Lambda1 = 926+-72 (stat.) +-32 (sys.) MeV, respectively.

  9. The activity of {gamma}-emitters as measured by ionisation chambers the determination of the specific emission coefficient {gamma} for some radio-elements (1961); Mesure de l'activite des emetteurs {gamma} par chambre d'ionisation. Determination du coefficient specifique d'emission {gamma} de quelques radioelements (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Engelmann, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-06-15

    The object of this work is to study techniques of measurement using the gamma ionisation chamber, making it possible either to measure the activities of radioactive sources, or to determine the specific emission coefficient {gamma} (or the coefficient K) of a given radioelement. The ionisation chambers studied belong to two categories: graphites cavity-chambers, and 4 {pi} {gamma} chambers. For the cavity-chamber measurements, the different correction factors of which account must be taken have been calculated, in particular the geometric and hygrometric corrections. The absorption and auto-absorption corrections have led to the introduction of the notion of the 'effective energy {gamma}' of a radioelement. In the case of 4 {pi} {gamma} chambers, it has been shown that appropriately shaped electrodes make it possible to improve their performances. One of the chambers described permits the measurement of {beta} emitters using the associated Bremsstrahlung. In order to measure the K coefficient of some radioelements, it has been found useful a 4 {pi} {gamma} chamber with graphite walls, the measurement being carried out by comparison with a radium standard. The validity of the method was checked with radioelements for whom the K coefficient values are well-known ({sup 24}Na, {sup 60}Co, {sup 131}I, {sup 198}Au). For other radioelements, the following values were obtained (expressed in r cm{sup 3} mc{sup -1} h{sup -1}): {sup 51}Cr: 0,18; {sup 56}Mn: 8,8; {sup 65}Zn: 3,05; {sup 124}Sb: 9,9; {sup 134}Cs: 9,3; {sup 137}Cs: 3,35; {sup 141}Ce: 0,46; {sup 170}Tm: 0,023; {sup 192}Ir: 24,9; {sup 203}Hg: 1,18; These values have been corrected for the contribution to the dose of the fluorescent radiation which may be emitted by the source, except in the case of Tm{sup 170}. In the last part of this work, the performances of the different electro-metric devices used were compared. (author) [French] Le but de ce travail est d'etudier les techniques de mesure par chambre d

  10. A new measurement of the $K^{\\pm} \\rightarrow \\pi^{\\pm} \\gamma \\gamma$ decay at the NA48/2 experiment

    CERN Document Server

    Batley, J.R.; Lazzeroni, C.; Munday, D.J.; Slater, M.W.; Wotton, S.A.; Arcidiacono, R.; Bocquet, G.; Cabibbo, N.; Ceccucci, A.; Cundy, D.; Falaleev, V.; Fidecaro, M.; Gatignon, L.; Gonidec, A.; Kubischta, W.; Norton, A.; Maier, A.; Patel, M.; Peters, A.; Balev, S.; Frabetti, P.L.; Gersabeck, E.; Goudzovski, E.; Hristov, P.; Kekelidze, V.; Kozhuharov, V.; Litov, L.; Madigozhin, D.; Molokanova, N.; Polenkevich, I.; Potrebenikov, Yu.; Stoynev, S.; Zinchenko, A.; Monnier, E.; Swallow, E.; Winston, R.; Rubin, P.; Walker, A.; Baldini, W.; Cotta Ramusino, A.; Dalpiaz, P.; Damiani, C.; Fiorini, M.; Gianoli, A.; Martini, M.; Petrucci, F.; Savrie, M.; Scarpa, M.; Wahl, H.; Bizzeti, A.; Lenti, M.; Veltri, M.; Calvetti, M.; Celeghini, E.; Iacopini, E.; Ruggiero, G.; Behler, M.; Eppard, K.; Kleinknecht, K.; Marouelli, P.; Masetti, L.; Moosbrugger, U.; Morales Morales, C.; Renk, B.; Wache, M.; Wanke, R.; Winhart, A.; Coward, D.; Dabrowski, A.; Fonseca Martin, T.; Shieh, M.; Szleper, M.; Velasco, M.; Wood, M.D.; Cenci, P.; Pepe, M.; Petrucci, M.C.; Anzivino, G.; Imbergamo, E.; Nappi, A.; Piccini, M.; Raggi, M.; Valdata-Nappi, M.; Cerri, C.; Fantechi, R.; Collazuol, G.; DiLella, L.; Lamanna, G.; Mannelli, I.; Michetti, A.; Costantini, F.; Doble, N.; Fiorini, L.; Giudici, S.; Pierazzini, G.; Sozzi, M.; Venditti, S.; Bloch-Devaux, B.; Cheshkov, C.; Cheze, J.B.; De Beer, M.; Derre, J.; Marel, G.; Mazzucato, E.; Peyaud, B.; Vallage, B.; Holder, M.; Ziolkowski, M.; Biino, C.; Cartiglia, N.; Marchetto, F.; Bifani, S.; Clemencic, M.; Goy Lopez, S.; Dibon, H.; Jeitler, M.; Markytan, M.; Mikulec, I.; Neuhofer, G.; Widhalm, L.

    2014-01-01

    The NA48/2 experiment at CERN collected two data samples with minimum bias trigger conditions in 2003 and 2004. A measurement of the rate and dynamic properties of the rare decay $K^\\pm\\to\\pi^\\pm\\gamma\\gamma$ from these data sets based on 149 decay candidates with an estimated background of $15.5\\pm0.7$ events is reported. The model-independent branching ratio in the kinematic range $z=(m_{\\gamma\\gamma}/m_K)^2>0.2$ is measured to be ${\\cal B}_{\\rm MI}(z>0.2) = (0.877 \\pm 0.089) \\times 10^{-6}$, and the branching ratio in the full kinematic range assuming a particular Chiral Perturbation Theory description to be ${\\cal B}(K_{\\pi\\gamma\\gamma}) = (0.910 \\pm 0.075) \\times 10^{-6}$.

  11. Gamma tomography apparatus

    International Nuclear Information System (INIS)

    Span, F.J.

    1988-01-01

    The patent concerns a gamma tomography apparatus for medical diagnosis. The apparatus comprises a gamma scintillation camera head and a suspension system for supporting and positioning the camera head with respect for the patient. Both total body scanning and single photon emission tomography can be carried out with the apparatus. (U.K.)

  12. Measurement of K40 in mine soil

    International Nuclear Information System (INIS)

    Salazar R, A. R.; Vega C, H. R.

    2014-10-01

    The natural radioactivity of the soil and the external exposition of the gamma radiation mainly depend of the geologic characteristics of the same soil. Their radioactivity levels provide information of the radio-nuclides distribution in the environment and allow estimating the radiological risk. For this reason, the objective of this work was to determine the K 40 concentration in four soil samples of a mine that produces Ag, Pb, Cu, and Zn, in Zacatecas State (Mexico), through gamma rays spectrometry using a Sodium Iodide detector doped with Thallium (Nal (Tl)). The results it was found that the soil sample contaminated by the liquid effluents of the mine it has a specific activity of 353 Bq/kg, for draw Los Angeles of 55 Bq/kg, in the old dam of 307 Bq/kg and inside the mine of 485 Bq/kg, mentioning that all the sites refer to the same mine. Using a conversion factor of 0.043 n Gy/h (Bq/kg) -1 to calculate the absorbed dose in air of the natural radionuclide as the K 40 in the soil samples were founded the following dose reasons; of 15.18 n Gy/h, 2.37 n Gy/h, 13.2 n Gy/h and 20.86 n Gy/h, respectively. These results are similar to those reported for soil samples of Texas (USA), Karabuk (Turkey) and Kalpakkam (India), it should be noted that these samples are not mine samples; only were used like reference for this work. Our results are in an average of 300 Bq/kg that corresponds to one dose reason of 12.9 n Gy/h, comparing it with the highest value reported in the case of Chinese that is of 580 Bq/kg (24.94 n Gy/h) throwing a difference of 48.3% and compared with the smallest average value that belongs to Tripoli (Libya) of 270 Bq/kg (11.61 n Gy/h) is of 10%. The concentration average of the K 40 activity was below the world average of absorbed dose, which is of 55 n Gy/h of the average reported for the world, therefore these results can be used as a reference for the radioactivity analysis in the soil of this mine. (Author)

  13. Measurement of the ratio of branching fractions $B(B^0 \\to K^{\\ast 0} \\gamma) / B(B^0_s \\to \\phi \\gamma)$ and the direct $C\\!P$ asymmetry in $B^0 \\to K^{\\ast 0} \\gamma$

    CERN Document Server

    Aaij, R; Adametz, A; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves Jr, A A; Amato, S; Amhis, Y; Anderlini, L; Anderson, J; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Baesso, C; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bates, A; Bauer, C; Bauer, Th; Bay, A; Beddow, J; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blanks, C; Blouw, J; Blusk, S; Bobrov, A; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Büchler-Germann, A; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Cauet, Ch; Charles, M; Charpentier, Ph; Chen, P; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Corti, G; Couturier, B; Cowan, G A; Craik, D; Cunliffe, S; Currie, R; D'Ambrosio, C; David, P; David, P N Y; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Del Buono, L; Deplano, C; Derkach, D; Deschamps, O; Dettori, F; Dickens, J; Dijkstra, H; Diniz Batista, P; Domingo Bonal, F; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisele, F; Eisenhardt, S; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Elsby, D; Esperante Pereira, D; Falabella, A; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furcas, S; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garnier, J-C; Garofoli, J; Garra Tico, J; Garrido, L; Gascon, D; Gaspar, C; Gauld, R; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hampson, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Harrison, P F; Hartmann, T; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Hill, D; Hoballah, M; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Hussain, N; Huston, R S; Hutchcroft, D; Hynds, D; Iakovenko, V; Ilten, P; Imong, J; Jacobsson, R; Jaeger, A; Jahjah Hussein, M; Jans, E; Jansen, F; Jaton, P; Jean-Marie, B; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kaballo, M; Kandybei, S; Karacson, M; Karbach, T M; Keaveney, J; Kenyon, I R; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kim, Y M; Knecht, M; Kochebina, O; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucharczyk, M; Kudryavtsev, V; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J-P; Lefèvre, R; Leflat, A; Lefrançois, J; Leroy, O; Lesiak, T; Li, L; Li, Y; Li Gioi, L; Lieng, M; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; von Loeben, J; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Lu, H; Luisier, J; Mac Raighne, A; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Magnin, J; Malde, S; Mamunur, R M D; Manca, G; Mancinelli, G; Mangiafave, N; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Massafferri, A; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Mazurov, A; McCarthy, J; McGregor, G; McNulty, R; Meissner, M; Merk, M; Merkel, J; Milanes, D A; Minard, M-N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Mylroie-Smith, J; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Needham, M; Neufeld, N; Nguyen, A D; Nguyen-Mau, C; Nicol, M; Niess, V; Nikitin, N; Nikodem, T; Nomerotski, A; Novoselov, A; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, B K; Palano, A; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C; Pazos Alvarez, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perego, D L; Perez Trigo, E; Pérez-Calero Yzquierdo, A; Perret, P; Perrin-Terrin, M; Pessina, G; Petrolini, A; Phan, A; Picatoste Olloqui, E; Pie Valls, B; Pietrzyk, B; Pilař, T; Pinci, D; Playfer, S; Plo Casasus, M; Polci, F; Polok, G; Poluektov, A; Polycarpo, E; Popov, D; Popovici, B; Potterat, C; Powell, A; Prisciandaro, J; Pugatch, V; Puig Navarro, A; Qian, W; Rademacker, J H; Rakotomiaramanana, B; Rangel, M S; Raniuk, I; Rauschmayr, N; Raven, G; Redford, S; Reid, M M; dos Reis, A C; Ricciardi, S; Richards, A; Rinnert, K; Roa Romero, D A; Robbe, P; Rodrigues, E; Rodriguez Perez, P; Rogers, G J; Roiser, S; Romanovsky, V; Romero Vidal, A; Rosello, M; Rouvinet, J; Ruf, T; Ruiz, H; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salzmann, C; Sanmartin Sedes, B; Sannino, M; Santacesaria, R; Santamarina Rios, C; Santinelli, R; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Savrie, M; Savrina, D; Schaack, P; Schiller, M; Schindler, H; Schleich, S; Schlupp, M; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M-H; Schwemmer, R; Sciascia, B; Sciubba, A; Seco, M; Semennikov, A; Senderowska, K; Sepp, I; Serra, N; Serrano, J; Seyfert, P; Shapkin, M; Shapoval, I; Shatalov, P; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, O; Shevchenko, V; Shires, A; Silva Coutinho, R; Skwarnicki, T; Smith, N A; Smith, E; Smith, M; Sobczak, K; Soler, F J P; Solomin, A; Soomro, F; Souza, D; Souza De Paula, B; Spaan, B; Sparkes, A; Spradlin, P; Stagni, F; Stahl, S; Steinkamp, O; Stoica, S; Stone, S; Storaci, B; Straticiuc, M; Straumann, U; Subbiah, V K; Swientek, S; Szczekowski, M; Szczypka, P; Szumlak, T; T'Jampens, S; Teklishyn, M; Teodorescu, E; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Tolk, S; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Tran, M T; Tsaregorodtsev, A; Tuning, N; Ubeda Garcia, M; Ukleja, A; Uwer, U; Vagnoni, V; Valenti, G; Vazquez Gomez, R; Vazquez Regueiro, P; Vecchi, S; Velthuis, J J; Veltri, M; Veneziano, G; Vesterinen, M; Viaud, B; Videau, I; Vieira, D; Vilasis-Cardona, X; Visniakov, J; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Vorobyev, V; Voß, C; Voss, H; Waldi, R; Wallace, R; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; Webber, A D; Websdale, D; Whitehead, M; Wicht, J; Wiedner, D; Wiggers, L; Wilkinson, G; Williams, M P; Williams, M; Wilson, F F; Wishahi, J; Witek, M; Witzeling, W; Wotton, S A; Wright, S; Wu, S; Wyllie, K; Xie, Y; Xing, F; Xing, Z; Yang, Z; Young, R; Yuan, X; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, F; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhong, L; Zvyagin, A

    2013-01-01

    The ratio of branching fractions of the radiative $B$ decays $B^0\\rightarrow K^{*0}\\gamma$ and $B^0_s\\rightarrow\\phi\\gamma$ has been measured using an integrated luminosity of $1.0\\mbox{fb}^{-1}$ of $pp$ collision data collected by the LHCb experiment at a centre-of-mass energy of $\\sqrt{s}=7\\mathrm{\\,Te\\kern -0.1em V}$. The value obtained is \\begin{equation*} \\frac{{\\cal B}(B^0\\rightarrow K^{*0}\\gamma)}{{\\cal B} (B^0_s\\rightarrow\\phi\\gamma)} = 1.23 \\pm 0.06\\mathrm{\\,(stat.)} \\pm 0.04\\mathrm{\\,(syst.)} \\pm 0.10\\,(f_s/f_d)\\,, \\end{equation*} where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions $f_s/f_d$. Using the world average value for ${\\cal{B}}(B^0\\rightarrow K^{*0}\\gamma)$, the branching fraction ${\\cal{B}}(B^0_s\\rightarrow\\phi\\gamma)$ is measured to be $(3.5\\pm 0.4)\\times10^{-5}$. The direct CP asymmetry in $B^0\\rightarrow K^{*0}\\gamma$ decays has also been measured with the same data and f...

  14. Measurement of K{sup 40} in mine soil; Medicion de K{sup 40} en suelo de mina

    Energy Technology Data Exchange (ETDEWEB)

    Salazar R, A. R.; Vega C, H. R., E-mail: rosy_ojitos@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2014-10-15

    The natural radioactivity of the soil and the external exposition of the gamma radiation mainly depend of the geologic characteristics of the same soil. Their radioactivity levels provide information of the radio-nuclides distribution in the environment and allow estimating the radiological risk. For this reason, the objective of this work was to determine the K{sup 40} concentration in four soil samples of a mine that produces Ag, Pb, Cu, and Zn, in Zacatecas State (Mexico), through gamma rays spectrometry using a Sodium Iodide detector doped with Thallium (Nal (Tl)). The results it was found that the soil sample contaminated by the liquid effluents of the mine it has a specific activity of 353 Bq/kg, for draw Los Angeles of 55 Bq/kg, in the old dam of 307 Bq/kg and inside the mine of 485 Bq/kg, mentioning that all the sites refer to the same mine. Using a conversion factor of 0.043 n Gy/h (Bq/kg){sup -1} to calculate the absorbed dose in air of the natural radionuclide as the K{sup 40} in the soil samples were founded the following dose reasons; of 15.18 n Gy/h, 2.37 n Gy/h, 13.2 n Gy/h and 20.86 n Gy/h, respectively. These results are similar to those reported for soil samples of Texas (USA), Karabuk (Turkey) and Kalpakkam (India), it should be noted that these samples are not mine samples; only were used like reference for this work. Our results are in an average of 300 Bq/kg that corresponds to one dose reason of 12.9 n Gy/h, comparing it with the highest value reported in the case of Chinese that is of 580 Bq/kg (24.94 n Gy/h) throwing a difference of 48.3% and compared with the smallest average value that belongs to Tripoli (Libya) of 270 Bq/kg (11.61 n Gy/h) is of 10%. The concentration average of the K{sup 40} activity was below the world average of absorbed dose, which is of 55 n Gy/h of the average reported for the world, therefore these results can be used as a reference for the radioactivity analysis in the soil of this mine. (Author)

  15. The gamma contamination food factor

    International Nuclear Information System (INIS)

    Kukoc, A.H.; Anicin, I.V.; Adzic, P.R.

    1992-01-01

    We suggest that radioactive food contamination, as determined solely by a quantitative gamma-ray spectroscopic measurement, may, apart from the total activity per unit mass, be for quick reference conveniently characterized by another single figure which we call the ''Gamma Contamination Food Factor'' (GCFF). This factor may be defined as the ratio of the total specific activity of gamma-ray-emitting radionuclides in the food sample (except that of 40 K) to the specific activity of 40 K either in the sample itself or in an ''average man''. We discuss briefly the meaning and advantages of these definitions. (author)

  16. Observations and numerical studies of gamma-ray emission in colliding-wind binaries

    International Nuclear Information System (INIS)

    Reitberger, K.

    2014-01-01

    Massive stars in binary systems have long been regarded as potential sources of high-energy gamma rays. The emission is thought to arise in the region where the stellar winds collide, thereby producing accelerated particles which subsequently emit gamma rays.This scenario is supported by observations with the Fermi Large Area Telescope presented in this thesis. To address the underlying emission mechanisms in a quantitative way, numerical simulations that incorporate hydrodynamics, the acceleration of charged particles as well as the subsequent gamma-ray emission were found to be needed.This thesis presents the analysis of a high-energy gamma-ray source and its identification with the particle-accelerating colliding-wind binary system Eta Carinae. In order to go beyond the present understanding of such objects, this work provides detailed description of a new 3D-hydrodynamical model, which incorporates the line-driven acceleration of the winds, gravity, orbital motion and the radiative cooling of the shocked plasma, as well as the diffusive shock acceleration of charged particles in the wind collision region. In a subsequent step we simulate and study the resulting gamma-ray emission via relativistic bremsstrahlung, anisotropic inverse Compton radiation and neutral pion decay. (author) [de

  17. High-energy Emission from Nonrelativistic Radiative Shocks: Application to Gamma-Ray Novae

    Science.gov (United States)

    Vurm, Indrek; Metzger, Brian D.

    2018-01-01

    The observation of GeV gamma-rays from novae by Fermi/LAT demonstrates that the nonrelativistic radiative shocks in these systems can accelerate particles to energies of at least ∼10 GeV. The low-energy extension of the same nonthermal particle distribution inevitably gives rise to emission in the hard X-ray band. Above ≳ 10 {keV}, this radiation can escape the system without significant absorption/attenuation, and can potentially be detected by NuSTAR. We present theoretical models for hard X-ray and gamma-ray emission from radiative shocks in both leptonic and hadronic scenarios, accounting for the rapid evolution of the downstream properties due to the fast cooling of thermal plasma. We find that due to strong Coulomb losses, only a fraction of {10}-4{--}{10}-3 of the gamma-ray luminosity is radiated in the NuSTAR band; nevertheless, this emission could be detectable simultaneously with the LAT emission in bright gamma-ray novae with a ∼50 ks exposure. The spectral slope in hard X-rays is α ≈ 0 for typical nova parameters, thus serving as a testable prediction of the model. Our work demonstrates how combined hard X-ray and gamma-ray observations can be used to constrain properties of the nova outflow (velocity, density, and mass outflow rate) and particle acceleration at the shock. A very low X-ray to gamma-ray luminosity ratio ({L}{{X}}/{L}γ ≲ 5× {10}-4) would disfavor leptonic models for the gamma-ray emission. Our model can also be applied to other astrophysical environments with radiative shocks, including SNe IIn and colliding winds in massive star binaries.

  18. THERMAL X-RAY EMISSION FROM THE SHOCKED STELLAR WIND OF PULSAR GAMMA-RAY BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Zabalza, V.; Paredes, J. M. [Departament d' Astronomia i Meteorologia, Institut de Ciencies del Cosmos (ICC), Universitat de Barcelona (IEEC-UB), Marti i Franques 1, E08028 Barcelona (Spain); Bosch-Ramon, V., E-mail: vzabalza@am.ub.es [Dublin Institute for Advanced Studies, 31 Fitzwilliam Place, Dublin 2 (Ireland)

    2011-12-10

    Gamma-ray-loud X-ray binaries are binary systems that show non-thermal broadband emission from radio to gamma rays. If the system comprises a massive star and a young non-accreting pulsar, their winds will collide producing broadband non-thermal emission, most likely originated in the shocked pulsar wind. Thermal X-ray emission is expected from the shocked stellar wind, but until now it has neither been detected nor studied in the context of gamma-ray binaries. We present a semi-analytic model of the thermal X-ray emission from the shocked stellar wind in pulsar gamma-ray binaries, and find that the thermal X-ray emission increases monotonically with the pulsar spin-down luminosity, reaching luminosities of the order of 10{sup 33} erg s{sup -1}. The lack of thermal features in the X-ray spectrum of gamma-ray binaries can then be used to constrain the properties of the pulsar and stellar winds. By fitting the observed X-ray spectra of gamma-ray binaries with a source model composed of an absorbed non-thermal power law and the computed thermal X-ray emission, we are able to derive upper limits on the spin-down luminosity of the putative pulsar. We applied this method to LS 5039, the only gamma-ray binary with a radial, powerful wind, and obtain an upper limit on the pulsar spin-down luminosity of {approx}6 Multiplication-Sign 10{sup 36} erg s{sup -1}. Given the energetic constraints from its high-energy gamma-ray emission, a non-thermal to spin-down luminosity ratio very close to unity may be required.

  19. Fermi Discovery of Gamma-Ray Emission from NGC 1275

    Energy Technology Data Exchange (ETDEWEB)

    Abdo, Aous A.; /Naval Research Lab, Wash., D.C.; Ackermann, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Ajello, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Asano, K.; /Tokyo Inst. Tech.; Baldini, L.; /INFN, Pisa; Ballet, J.; /DAPNIA, Saclay; Barbiellini, Guido; /INFN, Trieste /Trieste U.; Bastieri, Denis; /INFN, Padua /Padua U.; Baughman, B.M.; /Ohio State U.; Bechtol, K.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bellazzini, R.; /INFN, Pisa; Blandford, R.D.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bloom, Elliott D.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bonamente, E.; /INFN, Perugia /Perugia U.; Borgland, A.W.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bregeon, J.; /INFN, Pisa; Brez, A.; /INFN, Pisa; Brigida, M.; /Bari U. /INFN, Bari; Bruel, P.; /Ecole Polytechnique; Burnett, Thompson H.; /Washington U., Seattle; Caliandro, G.A.; /Bari U. /INFN, Bari /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /IASF, Milan /IASF, Milan /DAPNIA, Saclay /ASDC, Frascati /INFN, Perugia /Perugia U. /SISSA, Trieste /George Mason U. /Naval Research Lab, Wash., D.C. /NASA, Goddard /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /INFN, Perugia /Perugia U. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Montpellier U. /ASDC, Frascati /Sonoma State U. /Stockholm U., OKC /Royal Inst. Tech., Stockholm /Stockholm U. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Naval Research Lab, Wash., D.C. /INFN, Trieste /Bari U. /INFN, Bari /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /NASA, Goddard /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /CENBG, Gradignan /CENBG, Gradignan /Montpellier U. /Bari U. /INFN, Bari /Naval Research Lab, Wash., D.C. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /INFN, Trieste /Hiroshima U.; /more authors..

    2009-05-15

    We report the discovery of high-energy (E > 100 MeV) {gamma}-ray emission from NGC 1275, a giant elliptical galaxy lying at the center of the Perseus cluster of galaxies, based on observations made with the Large Area Telescope (LAT) of the Fermi Gamma-ray Space Telescope. The positional center of the {gamma}-ray source is only {approx}3{prime} away from the NGC 1275 nucleus, well within the 95% LAT error circle of {approx}5{prime}. The spatial distribution of {gamma}-ray photons is consistent with a point source. The average flux and power-law photon index measured with the LAT from 2008 August 4 to 2008 December 5 are F{sub {gamma}} = (2.10 {+-} 0.23) x 10{sup -7} ph (>100 MeV) cm{sup -2} s{sup -1} and {Gamma} = 2.17 {+-} 0.05, respectively. The measurements are statistically consistent with constant flux during the four-month LAT observing period. Previous EGRET observations gave an upper limit of F{sub {gamma}} < 3.72 x 10{sup -8} ph (>100 MeV) cm{sup -2} s{sup -1} to the {gamma}-ray flux from NGC 1275. This indicates that the source is variable on timescales of years to decades, and therefore restricts the fraction of emission that can be produced in extended regions of the galaxy cluster. Contemporaneous and historical radio observations are also reported. The broadband spectrum of NGC 1275 is modeled with a simple one-zone synchrotron/synchrotron self-Compton model and a model with a decelerating jet flow.

  20. Constraining |V(td)|/|V(ts)| Using Radiative Penguin B -> V(K*/rho/omega)gamma Decays

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Ping; /Wisconsin U., Madison

    2006-03-08

    Exclusive radiative penguin B decays, B {yields} (K*{sup 0}/K*{sup +}) and B {yields} ({rho}/{omega}){gamma}, are flavor-changing neutral-current (FCNC) processes. Studies of these decays are of special interest in testing Standard Model (SM) predictions and searching for other beyond-the-SM FCNC interactions. Using 89 x 10{sup 6} B{bar B} pairs from BABAR, we measure the branching fraction ({Beta}), CP-asymmetry ({Alpha}), and isospin asymmetry ({Delta}{sub 0-}) of B {yields} (K*{sup 0}/K*{sup +}){gamma} as follows: {Beta}(B{sup 0} {yields} K*{sup 0}{gamma}) = 3.92 {+-} 0.20(stat.) {+-} 0.24(syst.); {Beta}(B{sup +} {yields} K*{sup +}{gamma}) = 3.87 {+-} 0.28(stat.) {+-} 0.26(syst.); {Alpha}(B {yields} K*{gamma}) = -0.013 {+-} 0.36(stat.) {+-} 0.10(syst.); {Delta}{sub 0-}(B {yields} K*{gamma}) = 0.050 {+-} 0.045(stat.) {+-} 0.028(syst.) {+-} 0.024(R{sup +/0}). The 90% confidence intervals for the CP-asymmetry and the isospin-asymmetry in the B {yields} K*{gamma} decay are given as: -0.074 < {Alpha}(B {yields} K*{gamma}) < 0.049, -0.046 < {Delta}{sub 0-} (B {yields} K*{gamma}) < 0.146. We also search for B {yields} ({rho}/{omega}){gamma} decays using 211 x 10{sup 6} B{bar B} pairs from BABAR. No evidence for these decays is found. We set the upper limits at 90% confidence level for these decays: {Beta}(B{sup 0} {yields} {rho}{sup 0}{gamma}) < 0.4 x 10{sup -6}; {Beta}(B{sup +}{yields} {rho}{sup =}{gamma}) < 1.8 x 10{sup -6}; {Beta}(B{sup 0} {yields} {omega}{gamma}) < 1.0 x 10{sup -6}; {bar {Beta}}(B {yields} ({rho}/{omega}){gamma}) < 1.2 x 10{sup -6}. These results are in good agreement with the SM predictions. The branching fractions of these decays are then used to constrain the ratio |V{sub td}|/|V{sub ts}|.

  1. Quantifying K, U and Th contents of marine sediments using shipboard natural gamma radiation spectra measured on DV JOIDES Resolution

    Science.gov (United States)

    De Vleeschouwer, David; Dunlea, Ann G.; Auer, Gerald; Anderson, Chloe H.; Brumsack, Hans; de Loach, Aaron; Gurnis, Michael C.; Huh, Youngsook; Ishiwa, Takeshige; Jang, Kwangchul; Kominz, Michelle A.; März, Christian; Schnetger, Bernhard; Murray, Richard W.; Pälike, Heiko; Expedition 356 shipboard scientists, IODP

    2017-04-01

    During International Ocean Discovery Program (IODP) expeditions, shipboard-generated data provide the first insights into the cored sequences. The natural gamma radiation (NGR) of the recovered material, for example, is routinely measured on the ocean drilling research vessel DV JOIDES Resolution. At present, only total NGR counts are readily available as shipboard data, although full NGR spectra (counts as a function of gamma-ray energy level) are produced and archived. These spectra contain unexploited information, as one can estimate the sedimentary contents of potassium (K), thorium (Th), and uranium (U) from the characteristic gamma-ray energies of isotopes in the 40K, 232Th, and 238U radioactive decay series. Dunlea et al. [2013] quantified K, Th and U contents in sediment from the South Pacific Gyre by integrating counts over specific energy levels of the NGR spectrum. However, the algorithm used in their study is unavailable to the wider scientific community due to commercial proprietary reasons. Here, we present a new MATLAB algorithm for the quantification of NGR spectra that is transparent and accessible to future NGR users. We demonstrate the algorithm's performance by comparing its results to shore-based inductively coupled plasma-mass spectrometry (ICP-MS), inductively coupled plasma-emission spectrometry (ICP-ES), and quantitative wavelength-dispersive X-ray fluorescence (XRF) analyses. Samples for these comparisons come from eleven sites (U1341, U1343, U1366-U1369, U1414, U1428-U1430, U1463) cored in two oceans during five expeditions. In short, our algorithm rapidly produces detailed high-quality information on sediment properties during IODP expeditions at no extra cost. Dunlea, A. G., R. W. Murray, R. N. Harris, M. A. Vasiliev, H. Evans, A. J. Spivack, and S. D'Hondt (2013), Assessment and use of NGR instrumentation on the JOIDES Resolution to quantify U, Th, and K concentrations in marine sediment, Scientific Drilling, 15, 57-63.

  2. Polarized Emission from Gamma-Ray Burst Jets

    Directory of Open Access Journals (Sweden)

    Shiho Kobayashi

    2017-11-01

    Full Text Available I review how polarization signals have been discussed in the research field of Gamma-Ray Bursts (GRBs. I mainly discuss two subjects in which polarimetry enables us to study the nature of relativistic jets. (1 Jet breaks: Gamma-ray bursts are produced in ultra-relativistic jets. Due to the relativistic beaming effect, the emission can be modeled in a spherical model at early times. However, as the jet gradually slows down, we begin to see the edge of the jet together with polarized signals at some point. (2 Optical flash: later time afterglow is known to be insensitive to the properties of the original ejecta from the GRB central engine. However, a short-lived, reverse shock emission would enable us to study the nature of of GRB jets. I also briefly discuss the recent detection of optical circular polarization in GRB afterglow.

  3. B --> K$*\\gamma$ from hybrid sum rule

    CERN Document Server

    Narison, Stéphan

    1994-01-01

    Using the {\\it hybrid} moments-Laplace sum rule (HSR), which is well-defined for M_b \\rar \\infty, in contrast with the popular double Borel (Laplace) sum rule (DLSR), which blows up in this limit when applied to the heavy-to-light processes, we show that the form factor of the B \\rar K^* \\ \\gamma radiative transition is dominated by the light-quark condensate for M_b \\rar \\infty and behaves like \\sqrt M_b. The form factor is found to be F^{B\\rar K^*}_1(0) \\simeq (30.8 \\pm 1.3 \\pm 3.6 \\pm 0.6)\\times 10^{-2}, where the errors come respectively from the procedure in the sum rule analysis, the errors in the input and in the SU(3)_f-breaking parameters. This result leads to Br(B\\rar K^* \\ \\gamma) \\simeq (4.45 \\pm 1.12) \\times 10^{-5} in agreement with the recent CLEO data. Parametrization of the M_b-dependence of the form factor including the SU(3)_f-breaking effects is given in (26), which leads to F^{B\\rar K^*}_1(0)/ F^{B\\rar \\rho}_1(0) \\simeq (1.14 \\pm 0.02).

  4. Measurement and Analysis of Specific Activities of 238U, 232Th,226Ra, 40K and 137Cs in Soil Samples from Phatthalung Province (Thailand) using Gamma Ray Spectrometry

    International Nuclear Information System (INIS)

    Daoh, Murnee; Kessaratikoon, Prasong; Udomsomporn, Suchin

    2011-06-01

    Full text: Specific activity of natural (238 U , 232 T h, 226 R a and 40 K ) and anthropogenic radionuclide (137 C s) in 109 soil samples collected from 11 districts in Phathalung province have been measured and analyzed. Experimental results were obtained by using a high purity germanium (HPGe) detector and gamma spectrometry analysis system at Nuclear and Material Physics laboratory in Department of Physics Faculty of Science Thaksin University Songkhla Campus. Gamma ray radioactive standard sources 60 C o, 137 C s and 133 B a were used to calibrate the measurement system. The KCl and two reference materials (RGU-1 and RGTh-1) obtained from the International Atomic Energy Agency were also used to analyze and compute the 40 K , 238 U (or 226 R a) and 232 T h specific activity in all soil samples. The IAEA/SL-2 was also used to evaluate the specific activity of 137 C s in all soil samples. The measuring time of each sample was 10,800 seconds. It was found that specific activity ranged from 148.17 to 11276.78 Bq/kg for 40 K , 58.29 to 518.45 Bq/kg for 226 R a, 8.40 to 236.19 Bq/kg for 232 T h and 0.00 tp 12.39 Bq/kg for 137 C s with mean values of 3573.35 ± 203.89 Bq/kg, 135.89 ± 6.71 Bq/kg, 76.34 ± 5.32 Bq/kg and 1.05 ± 0.70 Bq/kg respectively. Furthermore, absorbed dose rate in air (D), radium equivalent activity (Ra e q), external hazard index (H e x), and annual effective dose rate (AEDout) of this area were also evaluated by using the mean values of specific activities of the 40 K , 226 R a and 232 T h. Moreover, the experimental results were also compared with Office of Atoms for Peace (OAP) research data, Thailand and global radioactivity measurement and evaluations. The radioactive contour maps of specific activities of natural and anthropogenic radionuclides from this study were created by using the program ArcGis Version 9.2

  5. The activity of {gamma}-emitters as measured by ionisation chambers the determination of the specific emission coefficient {gamma} for some radio-elements (1961); Mesure de l'activite des emetteurs {gamma} par chambre d'ionisation. Determination du coefficient specifique d'emission {gamma} de quelques radioelements (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Engelmann, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1962-06-15

    The object of this work is to study techniques of measurement using the gamma ionisation chamber, making it possible either to measure the activities of radioactive sources, or to determine the specific emission coefficient {gamma} (or the coefficient K) of a given radioelement. The ionisation chambers studied belong to two categories: graphites cavity-chambers, and 4 {pi} {gamma} chambers. For the cavity-chamber measurements, the different correction factors of which account must be taken have been calculated, in particular the geometric and hygrometric corrections. The absorption and auto-absorption corrections have led to the introduction of the notion of the 'effective energy {gamma}' of a radioelement. In the case of 4 {pi} {gamma} chambers, it has been shown that appropriately shaped electrodes make it possible to improve their performances. One of the chambers described permits the measurement of {beta} emitters using the associated Bremsstrahlung. In order to measure the K coefficient of some radioelements, it has been found useful a 4 {pi} {gamma} chamber with graphite walls, the measurement being carried out by comparison with a radium standard. The validity of the method was checked with radioelements for whom the K coefficient values are well-known ({sup 24}Na, {sup 60}Co, {sup 131}I, {sup 198}Au). For other radioelements, the following values were obtained (expressed in r cm{sup 3} mc{sup -1} h{sup -1}): {sup 51}Cr: 0,18; {sup 56}Mn: 8,8; {sup 65}Zn: 3,05; {sup 124}Sb: 9,9; {sup 134}Cs: 9,3; {sup 137}Cs: 3,35; {sup 141}Ce: 0,46; {sup 170}Tm: 0,023; {sup 192}Ir: 24,9; {sup 203}Hg: 1,18; These values have been corrected for the contribution to the dose of the fluorescent radiation which may be emitted by the source, except in the case of Tm{sup 170}. In the last part of this work, the performances of the different electro-metric devices used were compared. (author) [French] Le but de ce travail est d'etudier les techniques de mesure par

  6. T-odd correlation in the $K_{l3} \\gamma$ decay

    CERN Document Server

    Braguta, V V; Chalov, A E

    2002-01-01

    The dependence of the K/sup +/ to pi /sup 0/l/sup +/ nu /sub l/ gamma decay rate on the T-odd kinematical variable xi = q . Ýp/sub l/ * p /sub pi /¿/m/sub K//sup 3/ is investigated in the tree and one-loop approximations of the Standard Model (SM). It is shown that the partial width of the decay on the tree level is an even function of the variable, whereas the odd component is generated by the electromagnetic final-state interaction and determined by the imaginary parts of one-loop diagrams. The xi -odd components of the partial widths of the K/sup +/ to pi /sup 0/e/sup +/ nu /sub e/ gamma and K/sup +/ to pi /sup 0/ mu /sup +/ nu /sub mu / gamma decays calculated in the one-loop approximation are smaller by four orders of magnitude than the even components evaluated from the tree-level SM diagrams. (11 refs).

  7. Effects of 40 K on 131 I in vivo monitoring of thyroid

    International Nuclear Information System (INIS)

    Venturini, Luzia; Berti, Eduardo A.R.; Campos, Vicente P.; Rodrigues, Leticia L.C.

    1999-01-01

    This paper investigates how the detection limit for 131 I in vivo monitoring is affected by the 40 K body content. Gamma spectral data of 32 non-contaminated subjects were analyzed. The detection limit is determined for each case and the mean value is compared to the detection limit calculated for the shielded room. The detector used was a 3 x 3 NaI(TI) shielded with 3.2 cm lead and 0.7 cm aluminium. The results show that the interference of 40 K is very important in the determination of the activity of 131 I but it can be disregarded, in the occupational routine measurements, if the record level (Bq) is several times greater than the measured activity. (author)

  8. 40K/137Cs discrimination ratios to the aboveground organs of tropical plants

    International Nuclear Information System (INIS)

    Sanches, N.; Anjos, R.M.; Mosquera, B.

    2008-01-01

    In the present work, the accumulation of caesium and potassium in aboveground plant parts was studied in order to improve the understanding on the behaviour of monovalent cations in several compartments of tropical plants. We present the results for activity concentrations of 137 Cs and 40 K, measured by gamma spectrometry, from five tropical plant species: guava (Psidium guajava), mango (Mangifera indica), papaya (Carica papaya), banana (Musa paradisiaca), and manioc (Manihot esculenta). Caesium and potassium have shown a high level of mobility within the plants, exhibiting the highest values of concentration in the growing parts (fruits, leaves, twigs, and barks) of the woody fruit and large herbaceous shrub (such as manioc) species. In contrast, the banana and papaya plants exhibited the lowest levels of 137 Cs and 40 K in their growing parts. However, a significant correlation between activity concentrations of 137 Cs and 40 K was observed in these tropical plants. The 40 K/ 137 Cs discrimination ratios were approximately equal to unity in different compartments of each individual plant, suggesting the possibility of using caesium to predict the behaviour of potassium in several tropical species

  9. 40K/137Cs discrimination ratios to the aboveground organs of tropical plants.

    Science.gov (United States)

    Sanches, N; Anjos, R M; Mosquera, B

    2008-07-01

    In the present work, the accumulation of caesium and potassium in aboveground plant parts was studied in order to improve the understanding on the behaviour of monovalent cations in several compartments of tropical plants. We present the results for activity concentrations of (137)Cs and (40)K, measured by gamma spectrometry, from five tropical plant species: guava (Psidium guajava), mango (Mangifera indica), papaya (Carica papaya), banana (Musa paradisíaca), and manioc (Manihot esculenta). Caesium and potassium have shown a high level of mobility within the plants, exhibiting the highest values of concentration in the growing parts (fruits, leaves, twigs, and barks) of the woody fruit and large herbaceous shrub (such as manioc) species. In contrast, the banana and papaya plants exhibited the lowest levels of (137)Cs and (40)K in their growing parts. However, a significant correlation between activity concentrations of (137)Cs and (40)K was observed in these tropical plants. The (40)K/(137)Cs discrimination ratios were approximately equal to unity in different compartments of each individual plant, suggesting the possibility of using caesium to predict the behaviour of potassium in several tropical species.

  10. Determination of potassium-40 ({sup 40}K) in milk samples consumed in Iran and it's annual intake in different age categories

    Energy Technology Data Exchange (ETDEWEB)

    Abbasisiar, F. [Iranian Nuclear Regulatory Authority (INRA), Atomic Energy Organization of Iran (AEOI), Environmental Radiation Protection Div., National Radiation Protection Dept., Teheran (Iran, Islamic Republic of); Afshar, N. [Tarbiat Modarres Univ., Teheran (Iran, Islamic Republic of)

    2006-07-01

    A large fraction of the natural radiation exposure is due to ingestion of food containing naturally radionuclides such as {sup 40}K. Potassium-40 is the largest contributor to the internal radiation dose received b y man also it is one of the essential elements in the body. The potassium-40 that enters the blood stream after ingestion or inhalation is quickly distributed to all organs and tissues. This radionuclide is eliminated from the body with a biological half -life 30 days. Potassium-40 can present both an external and an internal health hazard. The strong gamma radiation associated with the electron-capture decay process makes external exposure to this isotope a concern. While in the body, it poses a health hazard from both the beta particles and gamma rays. The health hazard of this radionuclide is associated with the cell damage caused by the ionizing radiation that results from radioactive decay, with the general potential for subsequent cancer induction. So, determination of this radionuclide and its dose assessment due to food ingestion seems to be very important. For this purpose, The environmental Monitoring Program in Iran has been implemented from several years ago. Gamma radiation exposures and natural radioactivity measurements in different environmental samples such as soils, water and foodstuffs from different parts of country and also imported food products have been determined. Since milk and its products are one of the main diet foodstuffs, In the present work, the concentration of potassium-40 in milk samples (powder and fresh) consumed in the country has been determined using gamma spectrometry with a high-purity Ge detector (H.P-Ge detector). The results showed that the activity concentration of {sup 40}K in both dried powder milk samples imported to the country and locally produced fresh milk samples in different parts of the country was between 30 -50 Bq.kg-1. The annual intake of this radionuclide was measured considering yearly milk

  11. Evidence for TeV Gamma-Ray Emission from a Region of the Galactic Plane

    International Nuclear Information System (INIS)

    Atkins, R.; Gonzalez, M.M.; McEnery, J.E.; Wilson, M.E.; Benbow, W.; Coyne, D.G.; Dorfan, D.E.; Kelley, L.A.; Morales, M.F.; Parkinson, P.M. Saz; Williams, D.A.; Berley, D.; Blaufuss, E.; DeYoung, T.; Goodman, J.A.; Hays, E.; Lansdell, C.P.; Noyes, D.; Smith, A.J.; Sullivan, G.W.

    2005-01-01

    Gamma-ray emission from a narrow band at the galactic equator has previously been detected up to 30 GeV. We report evidence for a TeV gamma-ray signal from a region of the galactic plane by Milagro, a large-field-of-view water Cherenkov detector for extensive air showers. An excess with a significance of 4.5 standard deviations has been observed from the region of galactic longitude l (set-membership sign) (40 deg.,100 deg.) and latitude vertical bar b vertical bar γ (>3.5 TeV)=(6.4±1.4±2.1)x10 -11 cm -2 s -1 sr -1 . This flux is consistent with an extrapolation of the EGRET spectrum between 1 and 30 GeV in this galactic region

  12. A General Analysis of $\\gamma$ Determinations from $B \\to \\pi K$ Decays

    CERN Document Server

    Buras, Andrzej J; Buras, Andrzej J.; Fleischer, Robert

    1999-01-01

    We present a general parametrization of $B^\\pm\\to\\pi^\\pm K, \\pi^0K^\\pm$ and $B_d\\to\\pi^0 K, \\pi^\\mp K^\\pm$ decays, taking into account both electroweak penguin and rescattering effects. This formalism allows -- among other things -- an improved implementation of the strategies that were recently proposed by Neubert and Rosner to probe the CKM angle $\\gamma$ with the help of $B^\\pm\\to\\pi^\\pm K, \\pi^0K^\\pm$ decays. In particular, it allows us to investigate the sensitivity of the extracted value of $\\gamma$ to the basic assumptions of their approach. We find that certain SU(3)-breaking effects may have an important impact and emphasize that additional hadronic uncertainties are due to rescattering processes. The latter can be controlled by using SU(3) flavour symmetry arguments and additional experimental information provided by $B^\\pm\\to K^\\pm K$ modes. We propose a new strategy to probe the angle $\\gamma$ with the help of the neutral decays $B_d\\to\\pi^0 K, \\pi^\\mp K^\\pm$, which is theoretically cleaner than t...

  13. Smooth Optical Self-similar Emission of Gamma-Ray Bursts

    Energy Technology Data Exchange (ETDEWEB)

    Lipunov, Vladimir; Simakov, Sergey; Gorbovskoy, Evgeny; Vlasenko, Daniil, E-mail: lipunov2007@gmail.com [Lomonosov Moscow State University, Sternberg Astronomical Institute, Universitetsky prospect, 13, 119992, Moscow (Russian Federation)

    2017-08-10

    We offer a new type of calibration for gamma-ray bursts (GRB), in which some class of GRB can be marked and share a common behavior. We name this behavior Smooth Optical Self-similar Emission (SOS-similar Emission) and identify this subclasses of GRBs with optical light curves described by a universal scaling function.

  14. High-energy emissions from the gamma-ray binary LS 5039

    Energy Technology Data Exchange (ETDEWEB)

    Takata, J.; Leung, Gene C. K.; Cheng, K. S. [Department of Physics, University of Hong Kong, Pokfulam Road (Hong Kong); Tam, P. H. T.; Kong, A. K. H. [Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu, Taiwan (China); Hui, C. Y., E-mail: takata@hku.hk, E-mail: gene930@connect.hku.hk, E-mail: hrspksc@hku.hk [Department of Astronomy and Space Science, Chungnam National University, Daejeon (Korea, Republic of)

    2014-07-20

    We study mechanisms of multi-wavelength emissions (X-ray, GeV, and TeV gamma-rays) from the gamma-ray binary LS 5039. This paper is composed of two parts. In the first part, we report on results of observational analysis using 4 yr data of the Fermi Large Area Telescope. Due to the improvement of instrumental response function and increase of the statistics, the observational uncertainties of the spectrum in the ∼100-300 MeV bands and >10 GeV bands are significantly improved. The present data analysis suggests that the 0.1-100 GeV emissions from LS 5039 contain three different components: (1) the first component contributes to <1 GeV emissions around superior conjunction, (2) the second component dominates in the 1-10 GeV energy bands, and (3) the third component is compatible with the lower-energy tail of the TeV emissions. In the second part, we develop an emission model to explain the properties of the phase-resolved emissions in multi-wavelength observations. Assuming that LS 5039 includes a pulsar, we argue that emissions from both the magnetospheric outer gap and the inverse-Compton scattering process of cold-relativistic pulsar wind contribute to the observed GeV emissions. We assume that the pulsar is wrapped by two kinds of termination shock: Shock-I due to the interaction between the pulsar wind and the stellar wind and Shock-II due to the effect of the orbital motion. We propose that the X-rays are produced by the synchrotron radiation at the Shock-I region and the TeV gamma-rays are produced by the inverse-Compton scattering process at the Shock-II region.

  15. Measurements of the low-energy gamma-ray continuum emission from the Galactic Center direction

    International Nuclear Information System (INIS)

    Jardim, M.V.A.; Martin, I.M.; Jardim, J.O.D.

    1982-07-01

    The measurement of the gamma-ray continuum emission from the Galactic Center (GC) can provide us information about the physical processes taking place there at the site of emission. Using the data obtained with a balloon-borne gamma-ray telescope to measure gamma-rays in the energy interval between 0,3 and 3 MeV, which was launched on March 28, 1980 from Cachoeira Paulista (SP), we calculeted two points for the continuum spectrum in the range between 0,34 and 0,67 MeV. The points are related to the GC emission radiated in the longitude interval - 31 0 0 . The measurements are compatible with the observations in 1969 and 1972 by Haymes et alii and Johnson, respectively. The power law spectrum suggests that the main component for the gamma-ray continuum emission below 10 MeV is dominated by the bremsstrahlung due to relativistic electrons. (Author) [pt

  16. Search for $\\Theta^{++}$ Pentaquarks in the Exclusive Reaction $\\gamma p\\to K^+K^-p$

    Energy Technology Data Exchange (ETDEWEB)

    V. Kubarovsky; Marco Battaglieri; Raffaella De Vita; John Goett; Lei Guo; Gordon Mutchler; Paul Stoler; Dennis Weygand; Pawel Ambrozewicz; Marco Anghinolfi; Gegham Asryan; Harutyun AVAKIAN; Harutyun Avakian; H. Bagdasaryan; Nathan Baillie; Jacques Ball; Nathan Baltzell; V. Batourine; Ivan Bedlinski; Ivan Bedlinskiy; Matthew Bellis; Nawal Benmouna; Barry Berman; Angela Biselli; Sylvain Bouchigny; Sergey Boyarinov; Robert Bradford; Derek Branford; William Briscoe; William Brooks; Stephen Bueltmann; Volker Burkert; Cornel Butuceanu; John Calarco; Sharon Careccia; Daniel Carman; Shifeng Chen; Eric Clinton; Philip Cole; Patrick Collins; Philip Coltharp; Donald Crabb; Hall Crannell; Volker Crede; John Cummings; Rita De Masi; Daniel Dale; Enzo De Sanctis; Pavel Degtiarenko; Alexandre Deur; Kahanawita Dharmawardane; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; Michael Dugger; Oleksandr Dzyubak; Hovanes Egiyan; Kim Egiyan; Latifa Elouadrhiri; Paul Eugenio; Gleb Fedotov; Herbert Funsten; Marianna Gabrielyan; Liping Gan; Michel Garcon; Ashot Gasparian; Gagik Gavalian; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; Oleksandr Glamazdin; John Goetz; Evgueni Golovatch; Atilla Gonenc; Christopher Gordon; Ralf Gothe; Keith Griffioen; Michel Guidal; Nevzat Guler; Vardan Gyurjyan; Cynthia Hadjidakis; Kawtar Hafidi; Rafael Hakobyan; John Hardie; F. Hersman; Kenneth Hicks; Ishaq Hleiqawi; Maurik Holtrop; Charles Hyde-Wright; Yordanka Ilieva; David Ireland; Boris Ishkhanov; Eugeny Isupov; Mark Ito; David Jenkins; Hyon-Suk Jo; Kyungseon Joo; Henry Juengst; James Kellie; Mahbubul Khandaker; Wooyoung Kim; Franz Klein; Friedrich Klein; Alexei Klimenko; Mikhail Kossov; Laird Kramer; Joachim Kuhn; Sebastian Kuhn; Sergey Kuleshov; Jeff Lachniet; Jean Laget; Jorn Langheinrich; David Lawrence; Tsung-shung Lee; Ji Li; Kenneth Livingston; Hai-jiang Lu; Marion MacCormick; Nikolai Markov; Bryan McKinnon; Bernhard Mecking; Joseph Melone; Mac Mestayer; Curtis Meyer; Tsutomu Mibe; Konstantin Mikhaylov; Ralph Minehart; Marco Mirazita; Rory Miskimen; Vasiliy Mochalov; Viktor Mokeev; Ludyvine Morand; Steven Morrow; Maryam Moteabbed; Pawel Nadel-Turonski; Itaru Nakagawa; Rakhsha Nasseripour; Silvia Niccolai; Gabriel Niculescu; Maria-Ioana Niculescu; Bogdan Niczyporuk; Megh Niroula; Rustam Niyazov; Mina Nozar; Mikhail Osipenko; Alexander Ostrovidov; Kijun Park; Evgueni Pasyuk; Craig Paterson; Joshua Pierce; Nikolay Pivnyuk; Dinko Pocanic; Oleg Pogorelko; Sergey Pozdnyakov; John Price; Yelena Prok; Dan Protopopescu; Brian Raue; Gregory Riccardi; Giovanni Ricco; Marco Ripani; Barry Ritchie; Federico Ronchetti; Guenther Rosner; Patrizia Rossi; Franck Sabatie; Carlos Salgado; Joseph Santoro; Vladimir Sapunenko; Reinhard Schumacher; Vladimir Serov; Youri Sharabian; Nikolay Shvedunov; Elton Smith; Lee Smith; Daniel Sober; Aleksey Stavinskiy; Samuel Stepanyan; Stepan Stepanyan; Burnham Stokes; Igor Strakovski; Steffen Strauch; Mauro Taiuti; David Tedeschi; Aram Teymurazyan; Ulrike Thoma; Avtandil Tkabladze; Svyatoslav Tkachenko; Luminita Todor; Clarisse Tur; Maurizio Ungaro; Michael Vineyard; Alexander Vlassov; Lawrence Weinstein; Michael Williams; Elliott Wolin; Michael Wood; Amrit Yegneswaran; Lorenzo Zana; Jixie Zhang; Bo Zhao

    2006-04-28

    The reaction {gamma}p {yields} K{sup +}K{sup -}p was studied at Jefferson Lab with photon energies from 1.8 to 3.8 GeV using a tagged photon beam. The goal was to search for a {Theta}{sup ++} pentaquark, a narrow doubly charged baryon state having strangeness S = +1 and isospin I = 1, in the pK{sup +} invariant mass spectrum. No statistically significant evidence of a {Theta}{sup ++} was found. Upper limits on the total and differential production cross section for the reaction {gamma}p {yields} K{sup -}{Theta}{sup ++} were obtained in the mass range from 1.5 to 2.0 GeV/c{sup 2}, with an upper limit of about 0.15 nb, 95% C.L. for a narrow resonance with a mass M{sub {Theta}{sup ++}} = 1.54 GeV/c{sup 2}. This result places a very stringent upper limit on the {Theta}{sup ++} width.

  17. A comparison of creatinine concentration with 40K radioactivity in spot urine

    International Nuclear Information System (INIS)

    Yoo, Jaeryong; Park, Minjeong; Park, Seyoung; Ha, Wiho; Lee, Seungsook; Kim, Kwangpyo; Yoo, Jaeryong; Park, Minjeong

    2013-01-01

    24 hour urine collection is technically difficult to carry out and inconvenience for subjects. Also the result of 24 hour urine may vary from collection date. The spot urine assessment has large uncertainty that some spot urine concentrated or some spot urine diluted. Hence, it needs to apply normalization method for minimizing result of measurement the spot urine. In radiation emergency, specific gravity method was proposed which method use portable density meter for measuring density of urine and then normalization. The creatinine test recommend by ICRP (1968) and IAEA (1999) is the most common method for urine normalization. However, the creatinine result was various which depends upon sex, age, race and health conditions. Thus it needs to supplementary method for urine normalization. Natural potassium has isotopes those are K-39, K-40, and K-41, in the percentages of 93.08, 0.0118 and 6.91, respectively. Especially, the K-40 emits relatively high energy (1.46 MeV gamma ray) with a half life of 1.248 Χ 10 9 γ. The potassium is an essential element in human which works as homeostatic regulation. Thus human which works as homeostatic regulation. Thus human which works as homeostatic regulation. Thus human body contains specific amount of the potassium and then excreted regularly. And then K-40 is measurable in urine sample using HPGs detector. The purpose of this study is to estimate the variability of spot urine normalization method for assessing the internal exposure dose of hospital workers who work related with radiopharmaceutical produce. The use of creatinine as normalization of spot urine samples for internal dosimetry is possible to reduce level of uncertainty. However, creatinine range is wide which means the creatinine is not exactly correct reference value for normalization. Or some malfunction in creatinine analysis, it need to another supplementary method for normalization for adequately assessing the activity in spot urine samples. In this study

  18. Relation between gamma-ray emission, radio bursts, and proton fluxes from solar flares

    International Nuclear Information System (INIS)

    Fomichev, V.V.; Chertok, I.M.

    1985-01-01

    Data on solar gamma-ray flares, including 24 flares with gamma-ray lines, recorded up to June 1982, are analyzed. It is shown that from the point of view of radio emission the differences between flares with and without gamma-ray lines has a purely quantitative character: the former are accompanied by the most intense microwave bursts. Meter type II bursts are not a distinctive feature of flares with gamma-ray lines. Pulsed flares, regardless of the presence or absence of gamma-ray lines, are not accompanied by significant proton fluxes at the earth. On the whole, contrary to the popular opinion in the literature, flares with gamma-ray lines do not display a deficit of proton flux in interplanetary space in comparison with similar flares without gamma-ray lines. The results of quantitative diagnostics of proton flares based on radio bursts are not at variance with the presence of flares without detectable gamma-ray emission in lines but with a pronounced increase in the proton flux at the earth. 23 references

  19. Detection of gamma-ray emission from the Vela pulsar wind nebula with AGILE.

    Science.gov (United States)

    Pellizzoni, A; Trois, A; Tavani, M; Pilia, M; Giuliani, A; Pucella, G; Esposito, P; Sabatini, S; Piano, G; Argan, A; Barbiellini, G; Bulgarelli, A; Burgay, M; Caraveo, P; Cattaneo, P W; Chen, A W; Cocco, V; Contessi, T; Costa, E; D'Ammando, F; Del Monte, E; De Paris, G; Di Cocco, G; Di Persio, G; Donnarumma, I; Evangelista, Y; Feroci, M; Ferrari, A; Fiorini, M; Fuschino, F; Galli, M; Gianotti, F; Hotan, A; Labanti, C; Lapshov, I; Lazzarotto, F; Lipari, P; Longo, F; Marisaldi, M; Mastropietro, M; Mereghetti, S; Moretti, E; Morselli, A; Pacciani, L; Palfreyman, J; Perotti, F; Picozza, P; Pittori, C; Possenti, A; Prest, M; Rapisarda, M; Rappoldi, A; Rossi, E; Rubini, A; Santolamazza, P; Scalise, E; Soffitta, P; Striani, E; Trifoglio, M; Vallazza, E; Vercellone, S; Verrecchia, F; Vittorini, V; Zambra, A; Zanello, D; Giommi, P; Colafrancesco, S; Antonelli, A; Salotti, L; D'Amico, N; Bignami, G F

    2010-02-05

    Pulsars are known to power winds of relativistic particles that can produce bright nebulae by interacting with the surrounding medium. These pulsar wind nebulae are observed by their radio, optical, and x-ray emissions, and in some cases also at TeV (teraelectron volt) energies, but the lack of information in the gamma-ray band precludes drawing a comprehensive multiwavelength picture of their phenomenology and emission mechanisms. Using data from the AGILE satellite, we detected the Vela pulsar wind nebula in the energy range from 100 MeV to 3 GeV. This result constrains the particle population responsible for the GeV emission and establishes a class of gamma-ray emitters that could account for a fraction of the unidentified galactic gamma-ray sources.

  20. Observations of gamma-ray emission in solar flares

    International Nuclear Information System (INIS)

    Forrest, D.J.; Chupp, E.L.; Suri, A.N.; Reppin, C.

    1973-01-01

    This paper reviews the observations of gamma-ray emission made from the OSO-7 satellite in connection with two solar flares in early August 1972. The details of the measurements and a preliminary interpretation of some of the observed features are given. (U.S.)

  1. Role of albedo from the Gamma-400 telescope calorimeter when recording the primary gamma emission.

    Science.gov (United States)

    Ginsburg, V. L.; Kurnosova, L. V.; Labensky, A. G.; Topchiev, N. P.; Fradkin, M. I.; Kaplin, V. A.; Kaplin, D. V.; Loginov, V. A.; Maklyaev, E. F.; Runtso, M. F.; Gorchakov, E. V.

    A calorimeter albedo emission affecting the Gamma-400 telescope operation is studied, when recording γ-quanta at energies from 10 to 1000 GeV. Methods for diminishing this impact on measuring data are proposed.

  2. Radiation mutagenesis in lavender. I.Dose and emissive power as affecting the radiosensitivity of lavender seeds in gamma-ray treatment

    International Nuclear Information System (INIS)

    Tsvetkov, R.

    1977-01-01

    The radiosensitivity has been investigated of dormant seeds of the widely distributed aboriginal Hemus and Karlovo varieties and of the Soviet Stepnaya lavender variety in treatment with gamma rays using 60 Co. Doses within 1 to 100 kRad are applied at different emissive power of the emitter. Both irradiated and nonirradiated control seeds are gibberellic acid treated. The dynamics of seed sprouting is followed up. The number of survived plants and peculiarities of their growth are registered. The radiosensitivity of Lavandula vera D.C. seeds is modified by the emissive power in equal doses applied. Stepnaya variety showed highest resistance, followed by Karlovo and Hemus varieties. Doses are ascertained with a stimulating, inhibiting, semilethal and lethal effect in regard to the separate varietoes. Both stimulation and injuring prove to be of saltatory character. The radiation injuring of doses with an inhibitory, semilethal and lethal effect positively correlate with the dose of all tested emissive powers of the gamma-emitter. (author)

  3. Measurement and Analysis of Specific Activities of Natural Radionuclides (40K, 226Ra and 232Th) in Beach Sand Samples from Talo Kapo Beach of Yaring District in Pattani Province using Gamma Ray Spectrometry

    Science.gov (United States)

    Daoh, M.; Masae, R. N.; Po-oh, S.; Boonkrongcheep; Kessaratikoon, P.

    2017-09-01

    The Specific Activities of 40K, 226Ra and 232Th were studied and determinate for 30 beach sand samples collected from Talo Kapo beach of Yaring district in Pattani province. Experimental results were obtained by using a high-purity germanium (HPGe) detector and gamma spectrometry analysis system. The IAEA-SOIL-6 reference materials obtained from the International Atomic Energy Agency were also used to analyze and compute the 40K, 226Ra and 232Th specific activity in all 30 beach sand samples. The measuring time of each sample is 10,000 seconds. It was found that specific activity range from 1805.37 - 3323.05, 40.96 - 2137.36 38.63 - 4329.28 Bq/kg for with mean values of 2242.79 ± 117.40, 250.18 ± 8.21 and 458.42 ± 7.68 Bq/kg for 40K, 226Ra and 232Th, respectively. Moreover, the results were also compared with research data in the south of Thailand, the Office of Atoms for Peace (OAP) annual report data and the recommended values which were proposed by United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR,)

  4. FERMI LAT DISCOVERY OF EXTENDED GAMMA-RAY EMISSIONS IN THE VICINITY OF THE HB 3 SUPERNOVA REMNANT

    Energy Technology Data Exchange (ETDEWEB)

    Katagiri, H.; Yoshida, K. [College of Science, Ibaraki University, 2-1-1, Bunkyo, Mito 310-8512 (Japan); Ballet, J. [Laboratoire AIM, CEA-IRFU/CNRS/Université Paris Diderot, Service d’Astrophysique, CEA Saclay, F-91191 Gif sur Yvette (France); Grondin, M.-H.; Lemoine-Goumard, M. [Centre d’Études Nucléaires de Bordeaux Gradignan, IN2P3/CNRS, Université Bordeaux 1, BP120, F-33175 Gradignan Cedex (France); Hanabata, Y. [Institute for Cosmic-Ray Research, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8582 (Japan); Hewitt, J. W. [Department of Physics and Center for Space Sciences and Technology, University of Maryland Baltimore County, Baltimore, MD 21250 (United States); Kubo, H., E-mail: hideaki.katagiri.sci@vc.ibaraki.ac.jp, E-mail: 13nm169s@gmail.com [Department of Physics, Graduate School of Science, Kyoto University, Kyoto (Japan)

    2016-02-20

    We report the discovery of extended gamma-ray emission measured by the Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope in the region of the supernova remnant (SNR) HB 3 (G132.7+1.3) and the W3 II complex adjacent to the southeast of the remnant. W3 is spatially associated with bright {sup 12}CO (J = 1–0) emission. The gamma-ray emission is spatially correlated with this gas and the SNR. We discuss the possibility that gamma rays originate in interactions between particles accelerated in the SNR and interstellar gas or radiation fields. The decay of neutral pions produced in nucleon–nucleon interactions between accelerated hadrons and interstellar gas provides a reasonable explanation for the gamma-ray emission. The emission from W3 is consistent with irradiation of the CO clouds by the cosmic rays accelerated in HB 3.

  5. Young gamma-ray pulsar: from modeling the gamma-ray emission to the particle-in-cell simulations of the global magnetosphere

    Science.gov (United States)

    Brambilla, Gabriele; Kalapotharakos, Constantions; Timokhin, Andrey; Kust Harding, Alice; Kazanas, Demosthenes

    2016-04-01

    Accelerated charged particles flowing in the magnetosphere produce pulsar gamma-ray emission. Pair creation processes produce an electron-positron plasma that populates the magnetosphere, in which the plasma is very close to force-free. However, it is unknown how and where the plasma departs from the ideal force-free condition, which consequently inhibits the understanding of the emission generation. We found that a dissipative magnetosphere outside the light cylinder effectively reproduces many aspects of the young gamma-ray pulsar emission as seen by the Fermi Gamma-ray Space Telescope, and through particle-in-cell simulations (PIC), we started explaining this configuration self-consistently. These findings show that, together, a magnetic field structure close to force-free and the assumption of gamma-ray curvature radiation as the emission mechanism are strongly compatible with the observations. Two main issues from the previously used models that our work addresses are the inability to explain luminosity, spectra, and light curve features at the same time and the inconsistency of the electrodynamics. Moreover, using the PIC simulations, we explore the effects of different pair multiplicities on the magnetosphere configurations and the locations of the accelerating regions. Our work aims for a self-consistent modeling of the magnetosphere, connecting the microphysics of the pair-plasma to the global magnetosphere macroscopic quantities. This direction will lead to a greater understanding of pulsar emission at all wavelengths, as well as to concrete insights into the physics of the magnetosphere.

  6. Measurement of the ratio of branching fractions B(B{sup 0}{yields}K{sup Low-Asterisk 0}{gamma})/B(B{sub s}{sup 0}{yields}{phi}{gamma}) and the direct CP asymmetry in B{sup 0}{yields}K{sup Low-Asterisk 0}{gamma}

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Abellan Beteta, C. [Universitat de Barcelona, Barcelona (Spain); Adametz, A. [Physikalisches Institut, Ruprecht-Karls-Universitaet Heidelberg, Heidelberg (Germany); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Universite, Universite Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J.; Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Ali, S. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amhis, Y. [Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne (Switzerland); Anderlini, L. [Sezione INFN di Firenze, Firenze (Italy); Anderson, J. [Physik-Institut, Universitaet Zuerich, Zuerich (Switzerland); Appleby, R.B. [School of Physics and Astronomy, University of Manchester, Manchester (United Kingdom); and others

    2013-02-01

    The ratio of branching fractions of the radiative B decays B{sup 0}{yields}K{sup Low-Asterisk 0}{gamma} and B{sub s}{sup 0}{yields}{phi}{gamma} has been measured using an integrated luminosity of 1.0 fb{sup -1} of pp collision data collected by the LHCb experiment at a centre-of-mass energy of {radical}(s)=7 TeV. The value obtained is (B(B{sup 0}{yields}K{sup Low-Asterisk 0}{gamma}))/(B(B{sub s}{sup 0}{yields}{phi}{gamma})) =1.23{+-}0.06 (stat.){+-}0.04 (syst.){+-}0.10(f{sub s}/f{sub d}), where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions f{sub s}/f{sub d}. Using the world average value for B(B{sup 0}{yields}K{sup Low-Asterisk 0}{gamma}), the branching fraction B(B{sub s}{sup 0}{yields}{phi}{gamma}) is measured to be (3.5{+-}0.4) Multiplication-Sign 10{sup -5}. The direct CP asymmetry in B{sup 0}{yields}K{sup Low-Asterisk 0}{gamma} decays has also been measured with the same data and found to be A{sub CP}(B{sup 0}{yields}K{sup Low-Asterisk 0}{gamma})=(0.8{+-}1.7 (stat.){+-}0.9 (syst.))%. Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations.

  7. Interpretation of the galactic radio-continuum and gamma-ray emission

    International Nuclear Information System (INIS)

    Beuermann, K.P.

    1974-01-01

    An analysis is performed of the nonthermal radio-continuum and gamma-ray emission of the galactic disc, using a spiral-arm model of the Galaxy. The results for the 408 MHz brightness temperature and the >100 MeV gamma-ray line intensity as a function of galactic longitude at bsup(II)=0 deg are presented. The observational implications, as well as the uncertainties in the calculations, are briefly discussed. An estimate of the possible range of the inverse Compton contribution to the observed gamma-ray flux is made

  8. Effects of {sup 40} K on {sup 131} I in vivo monitoring of thyroid; Interferencia do {sup 40} K na monitoracao in vivo de {sup 131} I na tireoide

    Energy Technology Data Exchange (ETDEWEB)

    Venturini, Luzia; Berti, Eduardo A.R.; Campos, Vicente P.; Rodrigues, Leticia L.C. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    1999-11-01

    This paper investigates how the detection limit for {sup 131} I in vivo monitoring is affected by the {sup 40} K body content. Gamma spectral data of 32 non-contaminated subjects were analyzed. The detection limit is determined for each case and the mean value is compared to the detection limit calculated for the shielded room. The detector used was a 3 x 3 NaI(TI) shielded with 3.2 cm lead and 0.7 cm aluminium. The results show that the interference of {sup 40} K is very important in the determination of the activity of {sup 131} I but it can be disregarded, in the occupational routine measurements, if the record level (Bq) is several times greater than the measured activity. (author) 5 refs., 1 tab.; e-mail: lventur at net.ipen.br

  9. Dark matter properties implied by gamma ray interstellar emission models

    Energy Technology Data Exchange (ETDEWEB)

    Balázs, Csaba; Li, Tong, E-mail: csaba.balazs@monash.edu, E-mail: tong.li@monash.edu [ARC Centre of Excellence for Particle Physics at the Tera-scale, School of Physics and Astronomy, Monash University, Melbourne, Victoria 3800 (Australia)

    2017-02-01

    We infer dark matter properties from gamma ray residuals extracted using eight different interstellar emission scenarios proposed by the Fermi-LAT Collaboration to explain the Galactic Center gamma ray excess. Adopting the most plausible simplified ansatz, we assume that the dark matter particle is a Majorana fermion interacting with standard fermions via a scalar mediator. To trivially respect flavor constraints, we only couple the mediator to third generation fermions. Using this theoretical hypothesis, and the Fermi residuals, we calculate Bayesian evidences, including Fermi-LAT exclusion limits from 15 dwarf spheroidal galaxies as well. Our evidence ratios single out one of the Fermi scenarios as most compatible with the simplified dark matter model. In this scenario the dark matter (mediator) mass is in the 25-200 (1-1000) GeV range and its annihilation is dominated by bottom quark final state. Our conclusion is that the properties of dark matter extracted from gamma ray data are highly sensitive to the modeling of the interstellar emission.

  10. The emission of Gamma Ray Bursts as a test-bed for modified gravity

    Directory of Open Access Journals (Sweden)

    S. Capozziello

    2015-11-01

    Full Text Available The extreme physical conditions of Gamma Ray Bursts can constitute a useful observational laboratory to test theories of gravity where very high curvature regimes are involved. Here we propose a sort of curvature engine capable, in principle, of explaining the huge energy emission of Gamma Ray Bursts. Specifically, we investigate the emission of radiation by charged particles non-minimally coupled to the gravitational background where higher order curvature invariants are present. The coupling gives rise to an additional force inducing a non-geodesic motion of particles. This fact allows a strong emission of radiation by gravitationally accelerated particles. As we will show with some specific model, the energy emission is of the same order of magnitude of that characterizing the Gamma Ray Burst physics. Alternatively, strong curvature regimes can be considered as a natural mechanism for the generation of highly energetic astrophysical events. Possible applications to cosmology are discussed.

  11. Gamma-ray emission cross section from proton-incident spallation reaction

    International Nuclear Information System (INIS)

    Iga, Kiminori; Ishibashi, Kenji; Shigyo, Nobuhiro

    1996-01-01

    Gamma-ray emission double differential cross sections from proton-incident spallation reaction have been measured at incident energies of 0.8, 1.5 and 3.0 GeV with Al, Fe, In and Pb targets. The experimental results have been compared with calculate values of HETC-KFA2. The measured cross sections disagree with the calculated results in the gamma ray energies above 10 MeV. (author)

  12. Measurement of the Branching Fraction for the DecayB^{\\pm} to K^{*\\pm} gamma, K^{*\\pm} toK^{\\pm} \\pi^{0} with the BaBar Detector

    Energy Technology Data Exchange (ETDEWEB)

    koeneke, K

    2006-09-08

    The branching fraction of the radiative penguin B meson decay B{sup {+-}} {yields} K*{sup {+-}}{gamma} is measured at the PEP-II asymmetric energy e{sup +}e{sup -} collider, operating at a center of momentum energy of 10.58 GeV, the {Upsilon}(4S) resonance. This document concentrates on the case K*{sup {+-}} {yields} K{sup {+-}}{pi}{sup 0}; {pi}{sup 0} {yields} {gamma}{gamma}. This analysis is based on a dataset of 88.2-million {Upsilon}(4S) {yields} B{bar B} events corresponding to 81.3 fb{sup -1} collected with the BABAR detector.

  13. {sup 40}K/{sup 137}Cs discrimination ratios to the aboveground organs of tropical plants

    Energy Technology Data Exchange (ETDEWEB)

    Sanches, N. [Instituto de Fisica, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza s/n, Gragoata, Niteroi, CEP 24210-346, RJ (Brazil); Anjos, R.M. [Instituto de Fisica, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza s/n, Gragoata, Niteroi, CEP 24210-346, RJ (Brazil)], E-mail: meigikos@if.uff.br; Mosquera, B. [Instituto de Fisica, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza s/n, Gragoata, Niteroi, CEP 24210-346, RJ (Brazil)

    2008-07-15

    In the present work, the accumulation of caesium and potassium in aboveground plant parts was studied in order to improve the understanding on the behaviour of monovalent cations in several compartments of tropical plants. We present the results for activity concentrations of {sup 137}Cs and {sup 40}K, measured by gamma spectrometry, from five tropical plant species: guava (Psidium guajava), mango (Mangifera indica), papaya (Carica papaya), banana (Musa paradisiaca), and manioc (Manihot esculenta). Caesium and potassium have shown a high level of mobility within the plants, exhibiting the highest values of concentration in the growing parts (fruits, leaves, twigs, and barks) of the woody fruit and large herbaceous shrub (such as manioc) species. In contrast, the banana and papaya plants exhibited the lowest levels of {sup 137}Cs and {sup 40}K in their growing parts. However, a significant correlation between activity concentrations of {sup 137}Cs and {sup 40}K was observed in these tropical plants. The {sup 40}K/{sup 137}Cs discrimination ratios were approximately equal to unity in different compartments of each individual plant, suggesting the possibility of using caesium to predict the behaviour of potassium in several tropical species.

  14. Disentangling the gamma-ray emission towards Cygnus X: Sh2-104

    Science.gov (United States)

    Gotthelf, Eric

    2015-09-01

    We have just discovered distinct X-ray emission coincident with VER J2018+363, a TeV source recently resolved from the giant gamma-ray complex MGRO J2019+37 in the Cygnus region. NuSTAR reveals a hard point source and a diffuse nebula adjacent to and possibly part of Sh2-104, a compact HII region containing several young massive stellar clusters. There is reasonable evidence that these X-rays probe the origin of the gamma-ray flux, however, unrelated extragalactic sources need to be excluded. We propose a short Chandra observation to localize the X-ray emission to identify a putative pulsar or stellar counterpart(s). This is an important step to fully understand the energetics of the MGRO J2019+37 complex and the production of gamma-rays in star formation regions, in general.

  15. Spectrum of the isotropic diffuse gamma-ray emission derived from first-year Fermi Large Area Telescope data.

    Science.gov (United States)

    Abdo, A A; Ackermann, M; Ajello, M; Atwood, W B; Baldini, L; Ballet, J; Barbiellini, G; Bastieri, D; Baughman, B M; Bechtol, K; Bellazzini, R; Berenji, B; Blandford, R D; Bloom, E D; Bonamente, E; Borgland, A W; Bregeon, J; Brez, A; Brigida, M; Bruel, P; Burnett, T H; Buson, S; Caliandro, G A; Cameron, R A; Caraveo, P A; Casandjian, J M; Cavazzuti, E; Cecchi, C; Celik, O; Charles, E; Chekhtman, A; Cheung, C C; Chiang, J; Ciprini, S; Claus, R; Cohen-Tanugi, J; Cominsky, L R; Conrad, J; Cutini, S; Dermer, C D; de Angelis, A; de Palma, F; Digel, S W; Di Bernardo, G; do Couto e Silva, E; Drell, P S; Drlica-Wagner, A; Dubois, R; Dumora, D; Farnier, C; Favuzzi, C; Fegan, S J; Focke, W B; Fortin, P; Frailis, M; Fukazawa, Y; Funk, S; Fusco, P; Gaggero, D; Gargano, F; Gasparrini, D; Gehrels, N; Germani, S; Giebels, B; Giglietto, N; Giommi, P; Giordano, F; Glanzman, T; Godfrey, G; Grenier, I A; Grondin, M-H; Grove, J E; Guillemot, L; Guiriec, S; Gustafsson, M; Hanabata, Y; Harding, A K; Hayashida, M; Hughes, R E; Itoh, R; Jackson, M S; Jóhannesson, G; Johnson, A S; Johnson, R P; Johnson, T J; Johnson, W N; Kamae, T; Katagiri, H; Kataoka, J; Kawai, N; Kerr, M; Knödlseder, J; Kocian, M L; Kuehn, F; Kuss, M; Lande, J; Latronico, L; Lemoine-Goumard, M; Longo, F; Loparco, F; Lott, B; Lovellette, M N; Lubrano, P; Madejski, G M; Makeev, A; Mazziotta, M N; McConville, W; McEnery, J E; Meurer, C; Michelson, P F; Mitthumsiri, W; Mizuno, T; Moiseev, A A; Monte, C; Monzani, M E; Morselli, A; Moskalenko, I V; Murgia, S; Nolan, P L; Norris, J P; Nuss, E; Ohsugi, T; Omodei, N; Orlando, E; Ormes, J F; Paneque, D; Panetta, J H; Parent, D; Pelassa, V; Pepe, M; Pesce-Rollins, M; Piron, F; Porter, T A; Rainò, S; Rando, R; Razzano, M; Reimer, A; Reimer, O; Reposeur, T; Ritz, S; Rochester, L S; Rodriguez, A Y; Roth, M; Ryde, F; Sadrozinski, H F-W; Sanchez, D; Sander, A; Saz Parkinson, P M; Scargle, J D; Sellerholm, A; Sgrò, C; Shaw, M S; Siskind, E J; Smith, D A; Smith, P D; Spandre, G; Spinelli, P; Starck, J-L; Strickman, M S; Strong, A W; Suson, D J; Tajima, H; Takahashi, H; Takahashi, T; Tanaka, T; Thayer, J B; Thayer, J G; Thompson, D J; Tibaldo, L; Torres, D F; Tosti, G; Tramacere, A; Uchiyama, Y; Usher, T L; Vasileiou, V; Vilchez, N; Vitale, V; Waite, A P; Wang, P; Winer, B L; Wood, K S; Ylinen, T; Ziegler, M

    2010-03-12

    We report on the first Fermi Large Area Telescope (LAT) measurements of the so-called "extragalactic" diffuse gamma-ray emission (EGB). This component of the diffuse gamma-ray emission is generally considered to have an isotropic or nearly isotropic distribution on the sky with diverse contributions discussed in the literature. The derivation of the EGB is based on detailed modeling of the bright foreground diffuse Galactic gamma-ray emission, the detected LAT sources, and the solar gamma-ray emission. We find the spectrum of the EGB is consistent with a power law with a differential spectral index gamma = 2.41 +/- 0.05 and intensity I(>100 MeV) = (1.03 +/- 0.17) x 10(-5) cm(-2) s(-1) sr(-1), where the error is systematics dominated. Our EGB spectrum is featureless, less intense, and softer than that derived from EGRET data.

  16. A comparison of creatinine concentration with {sup 40}K radioactivity in spot urine

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Jaeryong; Park, Minjeong; Park, Seyoung; Ha, Wiho; Lee, Seungsook [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kim, Kwangpyo; Yoo, Jaeryong; Park, Minjeong [Kyung Hee Univ., Yongin (Korea, Republic of)

    2013-05-15

    24 hour urine collection is technically difficult to carry out and inconvenience for subjects. Also the result of 24 hour urine may vary from collection date. The spot urine assessment has large uncertainty that some spot urine concentrated or some spot urine diluted. Hence, it needs to apply normalization method for minimizing result of measurement the spot urine. In radiation emergency, specific gravity method was proposed which method use portable density meter for measuring density of urine and then normalization. The creatinine test recommend by ICRP (1968) and IAEA (1999) is the most common method for urine normalization. However, the creatinine result was various which depends upon sex, age, race and health conditions. Thus it needs to supplementary method for urine normalization. Natural potassium has isotopes those are K-39, K-40, and K-41, in the percentages of 93.08, 0.0118 and 6.91, respectively. Especially, the K-40 emits relatively high energy (1.46 MeV gamma ray) with a half life of 1.248 Χ 10{sup 9}γ. The potassium is an essential element in human which works as homeostatic regulation. Thus human which works as homeostatic regulation. Thus human which works as homeostatic regulation. Thus human body contains specific amount of the potassium and then excreted regularly. And then K-40 is measurable in urine sample using HPGs detector. The purpose of this study is to estimate the variability of spot urine normalization method for assessing the internal exposure dose of hospital workers who work related with radiopharmaceutical produce. The use of creatinine as normalization of spot urine samples for internal dosimetry is possible to reduce level of uncertainty. However, creatinine range is wide which means the creatinine is not exactly correct reference value for normalization. Or some malfunction in creatinine analysis, it need to another supplementary method for normalization for adequately assessing the activity in spot urine samples. In this

  17. Study on the thermoluminescent properties of K2YF5 and K2GdF5 crystals doped with optically active trivalent ions for gamma and neutrons dosimetry

    International Nuclear Information System (INIS)

    Silva, Edna Carla da

    2008-01-01

    In this work, the thermoluminescent (TL) properties of both double potassium yttrium fluoride (K 2 YF 5 ) and double potassium gadolinium fluoride (K 2 GdF 5 ) crystals doped with optically active rare earth ions were investigated from the point of view of gamma and neutron dosimetry. Crystalline platelets with thickness of about 1 mm, synthesized under hydrothermal conditions, were irradiated in order to study TL sensitivity, as well as dose and energy response, reproducibility and fading, in terms of Ce 3+ , Tb 3+ , Dy 3+ , e Pr 3+ concentrations. The K 2 YF 5 crystals doped with 1.0 at por cent Dy 3+ have been found to have an excellent linear TL response to X and gamma photons, in the range of 0.01 to 10 mGy. The TL output is comparable to that of CaS0 4 :Mn dosemeters. The main peak at 130 deg C has been found to have a TL response for 41.1 keV X-ray energy 32 times higher than that for 662 keV gamma rays. This fact points out that the K 2 Y 0.99 Dy 0.01 F 5 crystals have great potential for X-rays diagnostic and/or industrial radiography. On the other hand, the K 2 GdF 5 crystals doped with 5.0 at por cent Dy 3+ have been found to have the better TL response for gamma and fast neutron radiation, among the dopants studied. For gamma fields the TL response was linear for doses ranging from 0.1 to 200 mGy. The TL peak around 200 deg C can be deconvoluted into four individual peaks, all of them with linear behavior. For fast neutron radiation produced by an 241 Am B e source, the TL responses for doses ranging from 0.6 to 12 mSv were also linear and comparable to that of commercial TLD-600, irradiated at same conditions. The TL emission due to neutrons was in the high temperature range, above 200 deg C. These results points out that K 2 Gd 0.95 Dy 0.05 F 5 crystals are good candidates for use in neutron dosimetry applications. (author)

  18. Neutron-Activated Gamma-Emission: Technology Review

    Science.gov (United States)

    2012-01-01

    in Be9 + α  C12 + n and Be9 + α  3He4 + n. Chadwick (5) made use of the naturally occurring α-emitter polonium - 210 , which decays to lead-206 with...emission, the variation of gamma attenuation with distance and the presence of organic clutter (in food , fertilizer, dirt road, etc.) makes it 8...a neutron source by mixing a radioisotope that emits alpha particles, such as radium or polonium , with a low atomic weight isotope, usually in the

  19. Hard burst emission from the soft gamma repeater SGR 1900+14

    NARCIS (Netherlands)

    Woods, P.M.; Kouveliotou, C.; van Paradijs, J.; Briggs, M.S.; Hurley, K.; Göğüş, E.; Preece, R.D.; Giblin, T.W.; Thompson, C.; Duncan, R.C.

    1999-01-01

    We present evidence for burst emission from SGR 1900+14 with a power-law high-energy spectrum extending beyond 500 keV. Unlike previous detections of high-energy photons during bursts from soft gamma repeaters (SGRs), these emissions are not associated with extraordinarily bright flares. Not only is

  20. Transfer of K-40 from soil to grass and grass to milk: Samples of Brazilian rural areas

    International Nuclear Information System (INIS)

    Seabra, Karina B.M.; Peres, Sueli S.

    2017-01-01

    The knowledge of natural radionuclides concentration levels and their distribution in the environment allow to assessing the human exposure. Among of primordial radionuclides found in the earth's crust, 40 K is the largest contributor to the dose received by humans. In this paper, is presented a study carried out to estimate the activity concentration and to evaluate the transfer of 40 K along environmental compartments and exposure pathways. This study was performed in two rural sites of São Paulo, Brazil. In both locations, soil, grass, animal feed and cow milk samples were collected, conditioned, and analyzed by gamma spectrometry. The activity concentrations obtained were similar for both sites, showing, in this case, that the difference in the animal diet probably does not have a significant influence on the transfer of 40 K to cow's milk. (author)

  1. gamma-ray emission probabilities of sup 1 sup 9 sup 3 Os

    CERN Document Server

    Marnada, N; Ueda, N; Ikeda, K; Hayashi, N

    2002-01-01

    Precise measurements of disintegration rates by using a 4 pi beta-gamma coincidence apparatus have resulted in improved certainties of the principal gamma-ray emission probabilities of sup 1 sup 9 sup 3 Os. Most of the uncertainties are less than 1%, whereas the uncertainties of emission probabilities evaluated in the Nuclear Data Sheets (83 (1998) 921) are more than 6%. The precision is improved for the beta-ray branching ratio for direct transition to the ground state and the value is larger than the evaluated value by about 6%.

  2. Evaluation of ingestion dose to different age groups of public of Chutka (MP) environment due to 40K

    International Nuclear Information System (INIS)

    Tejpal, Menaria; Tiwari, S.N.; Mulchandani, U.; Goyal, S.; Ravi, P.M.; Tripathi, R.M.

    2014-01-01

    The activity levels of 40 K in the locally produced biological samples of food items as well as trend indicator samples from different locations of Chutka area of Madhya Pradesh site, were estimated by gamma spectrometry as part of preoperational survey. The observed 40 K activity in these samples is comparable with reported values from other areas of India. The annual effective dose through ingestion pathway due to 40 K is estimated for infant, child and adult categories of local population. The computed average ingestion dose due to intake of 40 K is found to be highest for infant child (0.34 mSv/y). Radionuclides enter the human body through complex mechanism including foodstuffs via the food chain. The most predominant naturally occurring radionuclides in foodstuffs is 40 K, other contributions to the radionuclides in foods include deposited fallouts from fission and activation products released during nuclear accidents and constituents of weapons tests released after detonation. The primary objective of the present study is to estimate the activity levels of 40 K in the dietary matrices and to evaluate internal dose due to annual intake of various dietary items by the population around Chutka environment, a proposed nuclear power station site near Jabalpur of Madhya Pradesh

  3. DETECTION OF GAMMA-RAY POLARIZATION IN PROMPT EMISSION OF GRB 100826A

    Energy Technology Data Exchange (ETDEWEB)

    Yonetoku, Daisuke; Murakami, Toshio; Sakashita, Tomonori; Morihara, Yoshiyuki; Takahashi, Takuya; Fujimoto, Hirofumi; Kodama, Yoshiki [College of Science and Engineering, School of Mathematics and Physics, Kanazawa University, Kakuma, Kanazawa, Ishikawa 920-1192 (Japan); Gunji, Shuichi; Toukairin, Noriyuki [Department of Physics, Faculty of Science, Yamagata University, 1-4-12, Koshirakawa, Yamagata, Yamagata 990-8560 (Japan); Mihara, Tatehiro [Cosmic Radiation Laboratory, RIKEN, 2-1, Hirosawa, Wako City, Saitama 351-0198 (Japan); Toma, Kenji [Department of Earth and Space Science, Osaka University, Toyonaka 560-0043 (Japan); Kubo, Shin, E-mail: yonetoku@astro.s.kanazawa-u.ac.jp [Clear Pulse Co. Ltd., 6-25-17, Chuo, Ohta-ku, Tokyo 143-0024 (Japan); Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), 3-1-1, Yoshinodai, Sagamihara, Kanagawa 229-8510 (Japan)

    2011-12-20

    We report the polarization measurement in prompt {gamma}-ray emission of GRB 100826A with the Gamma-Ray Burst Polarimeter on board the small solar-power-sail demonstrator IKAROS. We detected the firm change of polarization angle (PA) during the prompt emission with 99.9% (3.5{sigma}) confidence level, and the average polarization degree ({Pi}) of 27% {+-} 11% with 99.4% (2.9{sigma}) confidence level. Here the quoted errors are given at 1{sigma} confidence level for the two parameters of interest. The systematic errors have been carefully included in this analysis, unlike other previous reports. Such a high {Pi} can be obtained in several emission models of gamma-ray bursts (GRBs), including synchrotron and photospheric models. However, it is difficult to explain the observed significant change of PA within the framework of axisymmetric jet as considered in many theoretical works. The non-axisymmetric (e.g., patchy) structures of the magnetic fields and/or brightness inside the relativistic jet are therefore required within the observable angular scale of {approx}{Gamma}{sup -1}. Our observation strongly indicates that the polarization measurement is a powerful tool to constrain the GRB production mechanism, and more theoretical works are needed to discuss the data in more detail.

  4. Scientific prospects for spectroscopy of the gamma-ray burst prompt emission with SVOM

    Science.gov (United States)

    Bernardini, M. G.; Xie, F.; Sizun, P.; Piron, F.; Dong, Y.; Atteia, J.-L.; Antier, S.; Daigne, F.; Godet, O.; Cordier, B.; Wei, J.

    2017-10-01

    SVOM (Space-based multi-band astronomical Variable Objects Monitor) is a Sino-French space mission dedicated to the study of Gamma-Ray Bursts (GRBs) in the next decade, capable to detect and localise the GRB emission, and to follow its evolution in the high-energy and X-ray domains, and in the visible and NIR bands. The satellite carries two wide-field high-energy instruments: a coded-mask gamma-ray imager (ECLAIRs; 4-150 keV), and a gamma-ray spectrometer (GRM; 15-5500 keV) that, together, will characterise the GRB prompt emission spectrum over a wide energy range. In this paper we describe the performances of the ECLAIRs and GRM system with different populations of GRBs from existing catalogues, from the classical ones to those with a possible thermal component superimposed to their non-thermal emission. The combination of ECLAIRs and the GRM will provide new insights also on other GRB properties, as for example the spectral characterisation of the subclass of short GRBs showing an extended emission after the initial spike.

  5. Determination of specific concentrations of 40K, 238U and 232Th in mineral fertilizer samples

    International Nuclear Information System (INIS)

    Garcez, Ricardo W.D.; Lopes, Jose M.; Silva, Ademir X.

    2015-01-01

    The use of fertilizer is an established practice worldwide to promote agricultural productivity increased without increasing the planted area, resulting in native forests protection and increase of the food availability. Some kinds of fertilizer have in their chemical composition some radionuclides due the origin of its feedstock, such as 238 U, the 232 Th, and their descendants, beyond 40 K. Knowledge of the radioactivity levels in the environment is great importance to know the gamma radiation dose that the human being is exposed. For identification and quantitation of radionuclides, it was used gamma spectrometry where HPGe detector was used to obtain the spectra, and LabSOCS software for calculating the detection efficiency for each energy. The values of 232 Th specific concentrations ranged from 4.1 to 368.1 Bq.Kg -1 , the values of 238 U specific concentrations ranged from 16.0 to 647.7 Bq.Kg -1 and 40 K specific concentrations ranged from 19.1 to 12713 Bq.Kg -1 . Concentrations of values are consistent with those found in literature. (author)

  6. GAMMA-RAY EMISSION FROM TWO BLAZARS BEHIND THE GALACTIC PLANE: B2013+370 AND B2023+336

    International Nuclear Information System (INIS)

    Kara, E.; Errando, M.; Aliu, E.; Mukherjee, R.; Max-Moerbeck, W.; Readhead, A. C. S.; Richards, J. L.; Böttcher, M.; Fortin, P.; Halpern, J. P.

    2012-01-01

    B2013+370 and B2023+336 are two blazars at low-galactic latitude that were previously proposed to be the counterparts for the EGRET unidentified sources 3EG J2016+3657 and 3EG J2027+3429. Gamma-ray emission associated with the EGRET sources has been detected by the Fermi Gamma-ray Space Telescope, and the two sources, 1FGL J2015.7+3708 and 1FGL J2027.6+3335, have been classified as unidentified in the 1 year catalog. This analysis of the Fermi Large Area Telescope (LAT) data collected during 31 months reveals that the 1FGL sources are spatially compatible with the blazars and are significantly variable, supporting the hypothesis of extragalactic origin for the gamma-ray emission. The gamma-ray light curves are compared with 15 GHz radio light curves from the 40 m telescope at the Owens Valley Radio Observatory. Simultaneous variability is seen in both bands for the two blazar candidates. The study is completed with the X-ray analysis of 1FGL J2015.7+3708 using Swift observations that were triggered in 2010 August by a Fermi-detected flare. The resulting spectral energy distribution shows a two-component structure typical of blazars. We also identify a second source in the field of view of 1FGL J2027.6+3335 with similar characteristics to the known LAT pulsars. This study gives solid evidence favoring blazar counterparts for these two unidentified EGRET and Fermi sources, supporting the hypothesis that a number of unidentified gamma-ray sources at low-galactic latitudes are indeed of extragalactic origin.

  7. Gamma-Ray Emission in Dissipative Pulsar Magnetospheres: from Theory to Fermi Observations

    Science.gov (United States)

    Kalapotharakos, Konstantinos; Harding, Alice K.; Kazanas, Demosthenes

    2014-01-01

    We compute the patterns of gamma-ray emission due to curvature radiation in dissipative pulsar magnetospheres. Our ultimate goal is to construct macrophysical models that are able to reproduce the observed gamma-ray light curve phenomenology recently published in the Second Fermi Pulsar Catalog. We apply specific forms of Ohm's law on the open field lines using a broad range for the macroscopic conductivity values that result in solutions ranging, from near-vacuum to near-force-free. Using these solutions, we generate model gamma-ray light curves by calculating realistic trajectories and Lorentz factors of radiating particles under the influence of both the accelerating electric fields and curvature radiation reaction. We further constrain our models using the observed dependence of the phase lags between the radio and gamma-ray emission on the gamma-ray peak separation. We perform a statistical comparison of our model radio-lag versus peak-separation diagram and the one obtained for the Fermi standard pulsars. We find that for models of uniform conductivity over the entire open magnetic field line region, agreement with observations favors higher values of this parameter. We find, however, significant improvement in fitting the data with models that employ a hybrid form of conductivity, specifically, infinite conductivity interior to the light cylinder and high but finite conductivity on the outside. In these models the gamma-ray emission is produced in regions near the equatorial current sheet but modulated by the local physical properties. These models have radio lags near the observed values and statistically best reproduce the observed light curve phenomenology. Additionally, they also produce GeV photon cut-off energies.

  8. Early optical emission from the gamma-ray burst of 4 October 2002.

    Science.gov (United States)

    Fox, D W; Yost, S; Kulkarni, S R; Torii, K; Kato, T; Yamaoka, H; Sako, M; Harrison, F A; Sari, R; Price, P A; Berger, E; Soderberg, A M; Djorgovski, S G; Barth, A J; Pravdo, S H; Frail, D A; Gal-Yam, A; Lipkin, Y; Mauch, T; Harrison, C; Buttery, H

    2003-03-20

    Observations of the long-lived emission--or 'afterglow'--of long-duration gamma-ray bursts place them at cosmological distances, but the origin of these energetic explosions remains a mystery. Observations of optical emission contemporaneous with the burst of gamma-rays should provide insight into the details of the explosion, as well as into the structure of the surrounding environment. One bright optical flash was detected during a burst, but other efforts have produced negative results. Here we report the discovery of the optical counterpart of GRB021004 only 193 seconds after the event. The initial decline is unexpectedly slow and requires varying energy content in the gamma-ray burst blastwave over the course of the first hour. Further analysis of the X-ray and optical afterglow suggests additional energy variations over the first few days.

  9. Spatially extended K Iλ7699 emission in the nebula of VY CMa: kinematics and geometry

    Science.gov (United States)

    Smith, Nathan

    2004-04-01

    Long-slit echelle spectra reveal bright extended emission from the K Iλ7699 resonance line in the reflection nebula surrounding the extreme red supergiant VY Canis Majoris. The central star has long been known for its unusually bright K I emission lines, but this is the first report of intrinsic emission from K I in the nebula. The extended emission is not just a reflected spectrum of the star, but is due to resonant scattering by K atoms in the outer nebula itself, and is therefore a valuable probe of the kinematics and geometry of the circumstellar environment of VY CMa. Dramatic velocity structure is seen in the long-slit spectra, and most lines of sight through the nebula intersect multiple distinct velocity components. A faint `halo' at large distances from the star does appear to show a reflected spectrum, however, and suggests a systemic velocity of +40 km s-1 with respect to the Sun. The most striking feature is blueshifted emission from the filled interior of a large shell seen in images; the kinematic structure is reminiscent of a Hubble flow, and provides strong evidence for asymmetric and episodic mass loss due to localized eruptions on the stellar surface.

  10. Sample analysis using gamma ray induced fluorescent X-ray emission

    Energy Technology Data Exchange (ETDEWEB)

    Sood, B S; Allawadhi, K L; Gandhi, R; Batra, O P; Singh, N [Punjabi Univ., Patiala (India). Nuclear Science Labs.

    1983-01-01

    A non-destructive method for the analysis of materials using gamma ray-induced fluorescent x-ray emission has been developed. In this method, special preparation of very thin samples in which the absorption of the incident gamma rays and the emitted fluorescent x-rays is negligible, is not needed, and the absorption correction is determined experimentally. A suitable choice of the incident gamma ray energies is made to minimise enhancement effects through selective photoionization of the elements in the sample. The method is applied to the analysis of a typical sample of the soldering material using 279 keV and 59.5 keV gamma rays from /sup 203/Hg and /sup 241/Am radioactive sources respectively. The results of the analysis are found to agree well with those obtained from the chemical analysis.

  11. EGRET observations of diffuse gamma-ray emission in taurus and perseus

    International Nuclear Information System (INIS)

    Digel, Seth W.; Grenier, Isabelle A.

    2001-01-01

    We present an analysis of the interstellar gamma-ray emission observed toward the extensive molecular cloud complexes in Taurus and Perseus by the Energetic Gamma-Ray Experiment Telescope (EGRET). The region's large size (more than 300 square degrees) and location below the plane in the anticenter are advantageous for straightforward interpretation of the interstellar emission. The complex of clouds in Taurus has a distance of ∼140 pc and is near the center of the Gould Belt. The complex in Perseus, adjacent to Taurus on the sky, is near the rim of the Belt at a distance of ∼300 pc. The findings for the cosmic-ray density and the molecular mass-calibrating ratio N(H 2 )/W CO in Taurus and Perseus are compared with results for other nearby cloud complexes resolved by EGRET. The local clouds that now have been studied in gamma rays can be used to trace the distribution of high-energy cosmic rays within 1 kpc of the sun

  12. Discoveries by the Fermi Gamma Ray Space Telescope

    Science.gov (United States)

    Gehrels, Neil

    2011-01-01

    Fermi is a large space gamma-ray mission developed by NASA and the DOE with major contributions from France, Germany, Italy, Japan and Sweden. It was launched in June 2008 and has been performing flawlessly since then. The main instrument is the Large Area Telescope (LAT) operating in the 20 MeV to 300 GeV range and a smaller monitor instrument is the Gamma-ray Burst Monitor (GBM) operating in the 8 keV to 40 MeV range. New findings are occurring every week. Some of the key discoveries are: 1) Discovery of many new gamma-ray pulsars, including gamma-ray only and millisecond pulsars. 2) Detection of high energy gamma-ray emission from globular clusters, most likely due to summed emission from msec pulsars. 3) Discovery of delayed and extended high energy gamma-ray emission from short and long gamma-ray busts. 4) Detection of approximately 250 gamma-ray bursts per year with the GBM instrument. 5) Most accurate measurement of the cosmic ray electron spectrum between 30 GeV and 1 TeV, showing some excess above the conventional diffusion model. The talk will present the new discoveries and their implications.

  13. Energy input and response from prompt and early optical afterglow emission in gamma-ray bursts.

    Science.gov (United States)

    Vestrand, W T; Wren, J A; Wozniak, P R; Aptekar, R; Golentskii, S; Pal'shin, V; Sakamoto, T; White, R R; Evans, S; Casperson, D; Fenimore, E

    2006-07-13

    The taxonomy of optical emission detected during the critical first few minutes after the onset of a gamma-ray burst (GRB) defines two broad classes: prompt optical emission correlated with prompt gamma-ray emission, and early optical afterglow emission uncorrelated with the gamma-ray emission. The standard theoretical interpretation attributes prompt emission to internal shocks in the ultra-relativistic outflow generated by the internal engine; early afterglow emission is attributed to shocks generated by interaction with the surrounding medium. Here we report on observations of a bright GRB that, for the first time, clearly show the temporal relationship and relative strength of the two optical components. The observations indicate that early afterglow emission can be understood as reverberation of the energy input measured by prompt emission. Measurements of the early afterglow reverberations therefore probe the structure of the environment around the burst, whereas the subsequent response to late-time impulsive energy releases reveals how earlier flaring episodes have altered the jet and environment parameters. Many GRBs are generated by the death of massive stars that were born and died before the Universe was ten per cent of its current age, so GRB afterglow reverberations provide clues about the environments around some of the first stars.

  14. SEARCH FOR GAMMA-RAY EMISSION FROM MAGNETARS WITH THE FERMI LARGE AREA TELESCOPE

    International Nuclear Information System (INIS)

    Abdo, A. A.; Ackermann, M.; Ajello, M.; Allafort, A.; Blandford, R. D.; Bloom, E. D.; Borgland, A. W.; Bouvier, A.; Baldini, L.; Bellazzini, R.; Bregeon, J.; Ballet, J.; Barbiellini, G.; Baring, M. G.; Bastieri, D.; Bonamente, E.; Brigida, M.; Bruel, P.; Burnett, T. H.; Caliandro, G. A.

    2010-01-01

    We report on the search for 0.1-10 GeV emission from magnetars in 17 months of Fermi Large Area Telescope (LAT) observations. No significant evidence for gamma-ray emission from any of the currently known magnetars is found. The most stringent upper limits to date on their persistent emission in the Fermi energy range are estimated between ∼10 -12 and10 -10 erg s -1 cm -2 , depending on the source. We also searched for gamma-ray pulsations and possible outbursts, also with no significant detection. The upper limits derived support the presence of a cutoff at an energy below a few MeV in the persistent emission of magnetars. They also show the likely need for a revision of current models of outer-gap emission from strongly magnetized pulsars, which, in some realizations, predict detectable GeV emission from magnetars at flux levels exceeding the upper limits identified here using the Fermi-LAT observations.

  15. DISCOVERY OF TeV GAMMA-RAY EMISSION TOWARD SUPERNOVA REMNANT SNR G78.2+2.1

    Energy Technology Data Exchange (ETDEWEB)

    Aliu, E. [Department of Physics and Astronomy, Barnard College, Columbia University, NY 10027 (United States); Archambault, S. [Physics Department, McGill University, Montreal, QC H3A 2T8 (Canada); Arlen, T.; Aune, T. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States); Beilicke, M.; Buckley, J. H.; Bugaev, V.; Dickherber, R. [Department of Physics, Washington University, St. Louis, MO 63130 (United States); Benbow, W. [Fred Lawrence Whipple Observatory, Harvard-Smithsonian Center for Astrophysics, Amado, AZ 85645 (United States); Bird, R.; Cannon, A.; Collins-Hughes, E. [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Bouvier, A. [Santa Cruz Institute for Particle Physics and Department of Physics, University of California, Santa Cruz, CA 95064 (United States); Bradbury, S. M. [School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT (United Kingdom); Byrum, K. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States); Cesarini, A.; Connolly, M. P. [School of Physics, National University of Ireland Galway, University Road, Galway (Ireland); Ciupik, L. [Astronomy Department, Adler Planetarium and Astronomy Museum, Chicago, IL 60605 (United States); Cui, W. [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States); Duke, C., E-mail: amandajw@iastate.edu [Department of Physics, Grinnell College, Grinnell, IA 50112-1690 (United States); and others

    2013-06-20

    We report the discovery of an unidentified, extended source of very-high-energy gamma-ray emission, VER J2019+407, within the radio shell of the supernova remnant SNR G78.2+2.1, using 21.4 hr of data taken by the VERITAS gamma-ray observatory in 2009. These data confirm the preliminary indications of gamma-ray emission previously seen in a two-year (2007-2009) blind survey of the Cygnus region by VERITAS. VER J2019+407, which is detected at a post-trials significance of 7.5 standard deviations in the 2009 data, is localized to the northwestern rim of the remnant in a region of enhanced radio and X-ray emission. It has an intrinsic extent of 0.23 Degree-Sign .23 {+-} 0. Degree-Sign 03{sub stat-0 Degree-Sign .02sys}{sup +0 Degree-Sign .04} and its spectrum is well-characterized by a differential power law (dN/dE = N{sub 0} Multiplication-Sign (E/TeV){sup -{Gamma}}) with a photon index of {Gamma} = 2.37 {+-} 0.14{sub stat} {+-} 0.20{sub sys} and a flux normalization of N{sub 0} = 1.5 {+-} 0.2{sub stat} {+-} 0.4{sub sys} Multiplication-Sign 10{sup -12} photon TeV{sup -1} cm{sup -2} s{sup -1}. This yields an integral flux of 5.2 {+-} 0.8{sub stat} {+-} 1.4{sub sys} Multiplication-Sign 10{sup -12} photon cm{sup -2} s{sup -1} above 320 GeV, corresponding to 3.7% of the Crab Nebula flux. We consider the relationship of the TeV gamma-ray emission with the GeV gamma-ray emission seen from SNR G78.2+2.1 as well as that seen from a nearby cocoon of freshly accelerated cosmic rays. Multiple scenarios are considered as possible origins for the TeV gamma-ray emission, including hadronic particle acceleration at the SNR shock.

  16. Transfer of K-40 from soil to grass and grass to milk: Samples of Brazilian rural areas

    Energy Technology Data Exchange (ETDEWEB)

    Seabra, Karina B.M.; Peres, Sueli S., E-mail: karina.uerj@ymail.com, E-mail: suelip@ird.gov.br [Instituto de Radioproteção e Dosimetria (IRD/CNEN--RJ), Rio de Janeiro, RJ (Brazil)

    2017-07-01

    The knowledge of natural radionuclides concentration levels and their distribution in the environment allow to assessing the human exposure. Among of primordial radionuclides found in the earth's crust, {sup 40}K is the largest contributor to the dose received by humans. In this paper, is presented a study carried out to estimate the activity concentration and to evaluate the transfer of {sup 40}K along environmental compartments and exposure pathways. This study was performed in two rural sites of São Paulo, Brazil. In both locations, soil, grass, animal feed and cow milk samples were collected, conditioned, and analyzed by gamma spectrometry. The activity concentrations obtained were similar for both sites, showing, in this case, that the difference in the animal diet probably does not have a significant influence on the transfer of {sup 40}K to cow's milk. (author)

  17. High-energy emission from gamma-ray bursts

    International Nuclear Information System (INIS)

    Nolan, P.L.; Share, G.H.; Matz, S.; Chupp, E.L.; Forrest, D.J.; Rieger, E.

    1984-01-01

    We discuss broad-band continuum spectroscopy of 17 gamma-ray bursts above 0.3 MeV. The spectra were fitted by 3 trial functions, none of which provided an adequate fit to all the spectra. Most were too hard for a thermal bremsstarhlung function. Harder functional forms, such as thermal synchrotron or power-law, provide better fits for most of the spectra. The strong emission observed above 1 MeV raises some interesting theoretical questions

  18. Systematic search for very-high-energy gamma-ray emission from bow shocks of runaway stars

    Science.gov (United States)

    H.E.S.S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Akhperjanian, A. G.; Andersson, T.; Angüner, E. O.; Arakawa, M.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Becker Tjus, J.; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Büchele, M.; Bulik, T.; Capasso, M.; Carr, J.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chalme-Calvet, R.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Chrétien, M.; Coffaro, M.; Colafrancesco, S.; Cologna, G.; Condon, B.; Conrad, J.; Cui, Y.; Davids, I. D.; Decock, J.; Degrange, B.; Deil, C.; Devin, J.; deWilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O.'C.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Funk, S.; Füßling, M.; Gabici, S.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Gottschall, D.; Goyal, A.; Grondin, M.-H.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holler, M.; Horns, D.; Ivascenko, A.; Iwasaki, H.; Jacholkowska, A.; Jamrozy, M.; Janiak, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jogler, T.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katsuragawa, M.; Katz, U.; Kerszberg, D.; Khangulyan, D.; Khélifi, B.; Kieffer, M.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lefranc, V.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; Nakashima, S.; de Naurois, M.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Öttl, S.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Richter, S.; Rieger, F.; Romoli, C.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Saito, S.; Salek, D.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Seglar-Arroyo, M.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Simoni, R.; Sol, H.; Spanier, F.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stycz, K.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tsuji, N.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zabalza, V.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Żywucka, N.

    2018-04-01

    Context. Runaway stars form bow shocks by ploughing through the interstellar medium at supersonic speeds and are promising sources of non-thermal emission of photons. One of these objects has been found to emit non-thermal radiation in the radio band. This triggered the development of theoretical models predicting non-thermal photons from radio up to very-high-energy (VHE, E ≥ 0.1 TeV) gamma rays. Subsequently, one bow shock was also detected in X-ray observations. However, the data did not allow discrimination between a hot thermal and a non-thermal origin. Further observations of different candidates at X-ray energies showed no evidence for emission at the position of the bow shocks either. A systematic search in the Fermi-LAT energy regime resulted in flux upper limits for 27 candidates listed in the E-BOSS catalogue. Aim. Here we perform the first systematic search for VHE gamma-ray emission from bow shocks of runaway stars. Methods: Using all available archival H.E.S.S. data we search for very-high-energy gamma-ray emission at the positions of bow shock candidates listed in the second E-BOSS catalogue release. Out of the 73 bow shock candidates in this catalogue, 32 have been observed with H.E.S.S. Results: None of the observed 32 bow shock candidates in this population study show significant emission in the H.E.S.S. energy range. Therefore, flux upper limits are calculated in five energy bins and the fraction of the kinetic wind power that is converted into VHE gamma rays is constrained. Conclusions: Emission from stellar bow shocks is not detected in the energy range between 0.14 and 18 TeV.The resulting upper limits constrain the level of VHE gamma-ray emission from these objects down to 0.1-1% of the kinetic wind energy.

  19. Physicochemical Properties of Gamma-Irradiated Corn Starch

    International Nuclear Information System (INIS)

    Lee, Y.J.; Lim, S.T.; Kim, S.Y.; Han, S.M.; Kim, H.M.; Kang, I.J.

    2006-01-01

    Structural modification of corn starch by gamma irradiation was evaluated for under dry conditions at varied intensities from 0 to 40 kGy. Under scanning electron microscopy, the granule shape of corn starch was not significantly affected by the irradiation up to 40 kGy. In addition, X-ray diffraction and melting patterns of the irradiated starches were similar to those of the native starch, indicating that crystalline regions in the starch granules were not changed by irradiation. However, the pattern of gel permeation column chromatography showed a significant increase in partial hydrolysis of gamma irradiated starch samples

  20. Modulated High-Energy Gamma-Ray Emission from the Micro-quasar Cygnus X-3

    International Nuclear Information System (INIS)

    Abdo, A.A.; Cheung, C.C.; Dermer, C.D.; Grove, J.E.; Johnson, W.N.; Lovellette, M.N.; Makeev, A.; Ray, P.S.; Strickman, M.S.; Wood, K.S.; Abdo, A.A.; Cheung, C.C.; Ackermann, M.; Ajello, M.; Bechtol, K.; Berenji, B.; Blandford, R.D.; Bloom, E.D.; Borgland, A.W.; Cameron, R.A.; Chiang, J.; Claus, R.; Digel, S.W.; Silva, E.D.E.; Drell, P.S.; Dubois, R.; Focke, W.B.; Glanzman, T.; Godfrey, G.; Hayashida, M.; Johannesson, G.; Johnson, A.S.; Kamae, T.; Kocian, M.L.; Lande, J.; Madejski, G.M.; Michelson, P.F.; Mitthumsiri, W.; Monzani, M.E.; Moskalenko, I.V.; Murgia, S.; Nolan, P.L.; Paneque, D.; Reimer, A.; Reimer, O.; Rochester, L.S.; Romani, R.W.; Tanaka, T.; Thayer, J.B.; Tramacere, A.; Uchiyama, Y.; Usher, T.L.; Waite, A.P.; Wang, P.; Ackermann, M.; Ajello, M.; Bechtol, K.; Berenji, B.; Blandford, R.D.; Bloom, E.D.; Borgland, A.W.; Cameron, R.A.; Chiang, J.; Claus, R.; Digel, S.W.; Silva, E.D.E.; Drell, P.S.; Dubois, R.; Focke, W.B.; Glanzman, T.; Godfrey, G.; Hayashida, M.; Johannesson, G.; Johnson, A.S.; Kamae, T.; Kocian, M.L.; Lande, J.; Madejski, G.M.; Michelson, P.F.; Mitthumsiri, W.; Monzani, M.E.; Moskalenko, I.V.; Murgia, S.; Nolan, P.L.; Paneque, D.; Reimer, A.; Reimer, O.; Rochester, L.S.; Romani, R.W.; Tanaka, T.; Thayer, J.B.; Tramacere, A.; Uchiyama, Y.; Usher, T.L.; Waite, A.P.; Wang, P.; Axelsson, M.; Hjalmarsdotter, L.; Axelsson, M.; Conrad, J.; Hjalmarsdotter, L.; Jackson, M.S.; Meurer, C.; Ryde, F.; Ylinen, T.; Baldini, L.; Bellazzini, R.; Brez, A.; Kuss, M.; Latronico, L.; Omodei, N.; Pesce-Rollins, M.; Razzano, M.; Sgro, C.; Ballet, J.; Casandjian, J.M.; Chaty, S.; Corbel, S.; Grenier, I.A.; Koerding, E.; Rodriguez, J.; Starck, J.L.; Tibaldo, L.

    2009-01-01

    Micro-quasars are accreting black holes or neutron stars in binary systems with associated relativistic jets. Despite their frequent outburst activity, they have never been unambiguously detected emitting high-energy gamma rays. The Fermi Large Area Telescope (LAT) has detected a variable high-energy source coinciding with the position of the x-ray binary and micro-quasar Cygnus X-3. Its identification with Cygnus X-3 is secured by the detection of its orbital period in gamma rays, as well as the correlation of the LAT flux with radio emission from the relativistic jets of Cygnus X-3. The gamma-ray emission probably originates from within the binary system, opening new areas in which to study the formation of relativistic jets. (authors)

  1. Spin trapping of radicals formed in gamma-irradiated methanol: effect of the irradiation temperature from 77K to 300K

    International Nuclear Information System (INIS)

    Schlick, S.; Kevan, L.

    1976-01-01

    The neutral radicals formed in gamma-irradiated methanol were studied by spin trapping with phenyl-t-butylnitrone (PBN) in an attempt to probe the primary neutral radicals formed. In the temperature range from approximately 157 K to 300 K both CH 2 OH and CH 3 O spin adducts are observed and their limiting ratio at high PBN concentrations is CH 2 OH/CH 3 O=1.5 over this temperature range. Below approximately 157 K this ratio increases exponentially with decreasing temperature with an apparent activation energy of 5.8 kJ/mole (1.4 kcal/mole); this is consistent with the finding that only CH 2 OH radicals are formed by gamma radiolysis at 77 K. Several possible models for the primary neutral radicals formed in gamma-irradiated methanol and their subsequent reactions as a function of irradiation temperature are discussed. It is suggested that the primary radical formation mechanisms are similar in the gas and liquid phases and become temperature dependent when molecular motion is arrested in the solid. (Auth.)

  2. Measurement of 226Ra, 232Th and 40K radioactivity contents in by-product phosphogypsum from phosphate fertilizer industry using gamma ray spectrometric method

    International Nuclear Information System (INIS)

    Demirel, H.; Parmaksiz, A.; Vural, M.; Cakir, I.T.; Demircioglu, B.; Yucel, H.

    2004-01-01

    Full text: Phosphatic fertilizers are produced from the industrial processing of rock phosphate ores which are known to contain naturally occurring radionuclides such as 238 U and its daughter products. A high volume by-product known as phosphogypsum (PG) from the production of phosphoric acid and phosphate fertilizer causes serious storage and environmental problems in phosphoric acid industries. During the phosphoric acid production process, 226 Ra (t 1/2 =1600 y) ends up in PG which has chemical analogous to calcium element. Since the stockpiles of PG near the phosphatic fertilizer plants are huge amounts, the radioactivity contained in PG has measured in view of environmental radioactivity problem. In this work, the natural radioactivity in eighty PG samples taken from a stock near Samsun phosphoric fertilizer plant was measured by a high resolution gamma ray spectrometer. The mean activity of 226 Ra in PG samples has been found to be 546 Bq.kg -1 . However, the activities of 232 Th and 40 K measured in PG samples are negligibly small. In the presented paper, the gamma spectrometric method employed for this work is discussed and the radiological risk impact of radon gas emanation from 226 Ra mainly contained in PG, has been assessed

  3. Natural radioactivity (226Ra, 232Th and 40K) and assessment of radiological hazards in the Kestanbol granitoid, Turkey.

    Science.gov (United States)

    Canbaz, Buket; Cam, N Füsun; Yaprak, Günseli; Candan, Osman

    2010-09-01

    The surveys of natural gamma-emitting radionuclides in rocks and soils from the Ezine plutonic area were conducted during 2007. Direct dose measurement using a survey meter was carried out simultaneously. The present study, which is part of the survey, analysed the activity concentrations of (238)U, (232)Th and (40)K in granitoid samples from all over the region by HPGe gamma spectrometry. The activity concentrations of (226)Ra ranged from 94 to 637 Bq kg(-1), those of (232)Th ranged from 120 to 601 Bq kg(-1)and those of (40)K ranged from 1074 to 1527 Bq kg(-1) in the analysed rock samples from different parts of the pluton. To evaluate the radiological hazard of the natural radioactivity in the samples, the absorbed dose rate (D), the annual effective dose rate, the radium equivalent activity (Ra(eq)) and the external (H(ex)) hazard index were calculated according to the UNSCEAR 2000 report. The thorium-to-uranium concentration ratios were also estimated.

  4. Measurement of the ratio of branching fractions ${\\cal B}(B^0 \\to K^{\\ast 0} \\gamma)/{\\cal B}(B^0_s \\to \\phi \\gamma)$

    CERN Document Server

    Aaij, R; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Alkhazov, G; Alvarez Cartelle, P; Alves Jr, A A; Amato, S; Amhis, Y; Anderson, J; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Arrabito, L; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Bailey, D S; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bates, A; Bauer, C; Bauer, Th; Bay, A; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Bernet, R; Bettler, M -O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blanks, C; Blouw, J; Blusk, S; Bobrov, A; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Büchler-Germann, A; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Cauet, Ch; Charles, M; Charpentier, Ph; Chiapolini, N; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Collins, P; Comerma-Montells, A; Constantin, F; Contu, A; Cook, A; Coombes, M; Corti, G; Couturier, B; Cowan, G A; Currie, R; D'Ambrosio, C; David, P; David, P N Y; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Lorenzi, F; De Miranda, J M; De Paula, L; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Del Buono, L; Deplano, C; Derkach, D; Deschamps, O; Dettori, F; Dickens, J; Dijkstra, H; Diniz Batista, P; Domingo Bonal, F; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Dziurda, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisele, F; Eisenhardt, S; Ekelhof, R; Eklund, L; Elsasser, Ch; Elsby, D; Esperante Pereira, D; Falabella, A; Fanchini, E; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Fernandez Albor, V; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furcas, S; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garnier, J-C; Garofoli, J; Garra Tico, J; Garrido, L; Gascon, D; Gaspar, C; Gauld, R; Gauvin, N; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hampson, T; Hansmann-Menzemer, S; Harji, R; Harnew, N; Harrison, J; Harrison, P F; Hartmann, T; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Holubyev, K; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Huston, R S; Hutchcroft, D; Hynds, D; Iakovenko, V; Ilten, P; Imong, J; Jacobsson, R; Jaeger, A; Jahjah Hussein, M; Jans, E; Jansen, F; Jaton, P; Jean-Marie, B; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kaballo, M; Kandybei, S; Karacson, M; Karbach, T M; Keaveney, J; Kenyon, I R; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kim, Y M; Knecht, M; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kruzelecki, K; Kucharczyk, M; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J -P; Lefèvre, R; Leflat, A; Lefrançois, J; Leroy, O; Lesiak, T; Li, L; Li Gioi, L; Lieng, M; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; von Loeben, J; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Lu, H; Luisier, J; Mac Raighne, A; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Magnin, J; Malde, S; Mamunur, R M D; Manca, G; Mancinelli, G; Mangiafave, N; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martín Sánchez, A; Martinez Santos, D; Massafferri, A; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Maynard, B; Mazurov, A; McGregor, G; McNulty, R; Meissner, M; Merk, M; Merkel, J; Messi, R; Miglioranzi, S; Milanes, D A; Minard, M -N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Musy, M; Mylroie-Smith, J; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Nedos, M; Needham, M; Neufeld, N; Nguyen, A D; Nguyen-Mau, C; Nicol, M; Niess, V; Nikitin, N; Nikodem, T; Nomerotski, A; Novoselov, A; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, B K; Palacios, J; Palano, A; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Paterson, S K; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C; Pazos Alvarez, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perego, D L; Perez Trigo, E; Pérez-Calero Yzquierdo, A; Perret, P; Perrin-Terrin, M; Pessina, G; Petrella, A; Petrolini, A; Phan, A; Picatoste Olloqui, E; Pie Valls, B; Pietrzyk, B; Pilař, T; Pinci, D; Plackett, R; Playfer, S; Plo Casasus, M; Polok, G; Poluektov, A; Polycarpo, E; Popov, D; Popovici, B; Potterat, C; Powell, A; Prisciandaro, J; Pugatch, V; Puig Navarro, A; Qian, W; Rademacker, J H; Rakotomiaramanana, B; Rangel, M S; Raniuk, I; Raven, G; Redford, S; Reid, M M; dos Reis, A C; Ricciardi, S; Richards, A; Rinnert, K; Roa Romero, D A; Robbe, P; Rodrigues, E; Rodrigues, F; Rodriguez Perez, P; Rogers, G J; Roiser, S; Romanovsky, V; Rosello, M; Rouvinet, J; Ruf, T; Ruiz, H; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salzmann, C; Sannino, M; Santacesaria, R; Santamarina Rios, C; Santinelli, R; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Savrie, M; Savrina, D; Schaack, P; Schiller, M; Schleich, S; Schlupp, M; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M -H; Schwemmer, R; Sciascia, B; Sciubba, A; Seco, M; Semennikov, A; Senderowska, K; Sepp, I; Serra, N; Serrano, J; Seyfert, P; Shapkin, M; Shapoval, I; Shatalov, P; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, O; Shevchenko, V; Shires, A; Silva Coutinho, R; Skwarnicki, T; Smith, N A; Smith, E; Sobczak, K; Soler, F J P; Solomin, A; Soomro, F; Souza De Paula, B; Spaan, B; Sparkes, A; Spradlin, P; Stagni, F; Stahl, S; Steinkamp, O; Stoica, S; Stone, S; Storaci, B; Straticiuc, M; Straumann, U; Subbiah, V K; Swientek, S; Szczekowski, M; Szczypka, P; Szumlak, T; T'Jampens, S; Teodorescu, E; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Tolk, S; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Tran, M T; Tsaregorodtsev, A; Tuning, N; Ubeda Garcia, M; Ukleja, A; Urquijo, P; Uwer, U; Vagnoni, V; Valenti, G; Vazquez Gomez, R; Vazquez Regueiro, P; Vecchi, S; Velthuis, J J; Veltri, M; Viaud, B; Videau, I; Vieira, D; Vilasis-Cardona, X; Visniakov, J; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Voss, H; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; Webber, A D; Websdale, D; Whitehead, M; Wiedner, D; Wiggers, L; Wilkinson, G; Williams, M P; Williams, M; Wilson, F F; Wishahi, J; Witek, M; Witzeling, W; Wotton, S A; Wyllie, K; Xie, Y; Xing, F; Xing, Z; Yang, Z; Young, R; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, F; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhong, L; Zvyagin, A

    2012-01-01

    The ratio of branching fractions of the radiative $B$ decays $B^0\\to K^{*0}\\gamma$ and $B^0_s\\to \\phi\\gamma$ has been measured using $0.37\\,$fb$^{-1}$ of $pp$ collisions at a centre of mass energy of $\\sqrt{s}=7\\,$TeV, collected by the LHCb experiment. The value obtained is \\begin{equation} \\frac{{\\cal B}(B^0\\to K^{*0}\\gamma)}{{\\cal B}(B^0_s\\to \\phi\\gamma)} = 1.12 \\pm 0.08^{+0.06}_{-0.04}\\phantom{.}^{+0.09}_{-0.08},\

  5. Pulsed Gamma Rays from the Original Millisecond and Black Widow Pulsars: A Case for Caustic Radio Emission?

    Science.gov (United States)

    Guillemot, L.; Johnson, T. J.; Venter, C.; Kerr, M.; Pancrazi, B.; Livingstone, M.; Janssen, G. H.; Jaroenjittichai, P.; Kramer, M.; Cognard, I.; hide

    2011-01-01

    We report the detection of pulsed gamma-ray emission from the fast millisecond pulsars (MSPs) B1937+21 (also known as J1939+2134) and B1957+20 (J1959+2048) using 18 months of survey data recorded by the Fermi Large Area Telescope (LAT) and timing solutions based on radio observations conducted at the Westerbork and Nancay radio telescopes. In addition, we analyzed archival RXTE and XMM-Newton X-ray data for the two MSPs, confirming the X-ray emission properties of PSR B1937+21 and finding evidence (approx. 4(sigma)) for pulsed emission from PSR B1957+20 for the first time. In both cases the gamma-ray emission profile is characterized by two peaks separated by half a rotation and are in close alignment with components observed in radio and X-rays. These two pulsars join PSRs J0034..0534 and J2214+3000 to form an emerging class of gamma-ray MSPs with phase-aligned peaks in different energy bands. The modeling of the radio and gamma-ray emission pro les suggests co-located emission regions in the outer magnetosphere.

  6. Design of Dataflow Monitoring and Searches for B to omega gamma, B to phi gamma and B to phi K-short gamma at BaBar

    Energy Technology Data Exchange (ETDEWEB)

    Swain, J

    2004-03-16

    In May 2003 PEP-II achieved instantaneous luminosities in excess of 6 x 10{sup 33} cm{sup -2}s{sup -1}, twice the design luminosity. To permit BABAR to operate in this challenging environment, development work on the data acquisition system continued after detector commissioning. A vital part of this process is understanding the performance of the data acquisition system. Considerable effort was invested in the design and implementation of an application capable of collecting performance statistics from hundreds of CPUs in the data acquisition system during data collection. The monitoring application and some examples of its operation are presented in this thesis. Also presented here are the searches for the exclusive radiative one-loop decays, B {yields} {omega}{gamma}, B {yields} {phi}{gamma} and B{sup 0} {yields} {phi}K{sub S}{sup 0}{gamma}, using a sample of 89 million B{bar B} events. No significant signal is seen in any of the channels. Upper limits on the branching ratios, {Beta}, were found to be {Beta}(B {yields} {omega}{gamma}) < 3.0 x 10{sup -6}, {Beta}(B {yields} {phi}{gamma}) < 2.9 x 10{sup -6}, and {Beta}(B{sup 0} {yields} {phi}K{sub S}{sup 0}{gamma}) < 3.8 x 10{sup -6}, at the 90% confidence level.

  7. K X-Ray production cross sections for 40-180 keV protons

    International Nuclear Information System (INIS)

    Szegedi, S.; Hassan, M.F.

    2002-01-01

    In view of the importance of the X-ray production cross-section for the determination of element concentration in a given material, we have measured them experimentally for light elements Sc and Fe using proton beams of energy between 40 and 180 keV. The obtained K X-ray production cross-section is compared with the previous experimental results. The experimental K X-ray production cross-section for proton induced X-ray emission (PIXE) analysis, using low energy (200 keV) accelerator, have been improved

  8. INTEGRAL Upper Limits on Gamma-Ray Emission Associated with the Gravitational Wave Event GW150914

    DEFF Research Database (Denmark)

    Savchenko, V.; Ferrigno, C.; Mereghetti, S.

    2016-01-01

    Using observations of the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL), we place upper limits on the gamma-ray and hard X-ray prompt emission associated with the gravitational wave event GW150914, which was discovered by the LIGO/Virgo Collaboration. The omnidirectional view...... in the 75 keV-2 MeV energy range for typical spectral models. Our results constrain the ratio of the energy promptly released in gamma-rays in the direction of the observer to the gravitational wave energy Eγ/EGW ... of the gravitational wave source, based on the available predictions for prompt electromagnetic emission....

  9. Gamma rays from Cygnus X-1: Modeling and nonthermal pair production

    International Nuclear Information System (INIS)

    Dermer, C.D.; Liang, E.P.

    1988-02-01

    The gamma-ray bump observed between 0.5 and 2 MeV in the spectrum of Cygnus X-1 can be interpreted as the thermal emissions from a hot (kT/approximately/400 keV) pair-dominated cloud. We argue that the X-rays and gamma rays are produced in separate emission regions, and calculate the photon-photon pair production rate from X-ray and gamma-ray interactions in the vicinity of Cyg X-1 by employing a simplified geometry for the two emitting regions

  10. Measurement of the Branching Fraction of the Exclusive Decay B0 --> K*0gamma

    Energy Technology Data Exchange (ETDEWEB)

    Barrera, Barbara

    2000-10-16

    The b {yields} s{gamma} transition proceeds by a loop penguin diagram. It may be used to measure precisely the couplings of the top quark and to search for the effects of any new particles appearing in the loop. We present a preliminary measurement of the branching fraction of the exclusive decay, B{sup 0} {yields} K*{sup 0}{gamma}. They use 8.6 x 10{sup 6} B{bar B} decays to measure B(B{sup 0} {yields} K*{sup 0}{gamma}) = (5.4 {+-} 0.8 {+-} 0.5) x 10{sup -5}.

  11. HI-resolution gamma spectrometry measurements of U-238, TH-232, K-40 and CS-137 concentrations in soil samples from Capao Island at CTEx

    International Nuclear Information System (INIS)

    Oliveira, Luciano S.R.; Oliveira, Celio J.V.; Vilela, Paulo R.T.; Vital, Helio C.

    2013-01-01

    Absolute soil concentrations of U-238, Th-232, K-40 and Cs-137 samples collected from Capao Island have been measured by using Hi-Resolution Gamma HPGe Spectrometry. The area of interest encompasses an embankment in a mangrove swamp in Guaratiba, Rio de Janeiro, where nuclear, chemical and biological defense laboratories of the Brazilian Army Technology Center (CTEx) are located. In order to ensure that no significant environmental impact has resulted from neutron physics experiments performed in a graphite subcritical assembly in addition to the operation of two cesium-driven irradiating facilities, routine monitoring of those isotopes have been regularly performed. A total of eight 250 ml samples of mangrove and embankment soils were extracted from four sites of known coordinates within an area of 300 x 300 m 2 and remained stored for a minimum thirty-day period to allow equilibrium to be reached. Collection and preparation of samples were made according to previously established procedures. High purity germanium detectors were used to obtain high-resolution gamma spectra and counting times were required to exceed 30 hours in order to yield sufficient statistical accuracy. Energy and efficiency calibration curves of the counting system were determined by using the GENIE 2000 software for analysis of the gamma spectrum generated by nine standard sources with a total of 11 peak energies ranging from 0.05 to 1.3 MeV. The results, corrected for background, have been expressed as absolute specific activities. All experiments have been made in the Laboratory for Identification of Radiological Agents (LIAR) at CTEx. No trace of cesium-137 has been found and the measured levels of uranium-238, in the order of 10 Bq/kg, are close to the global mean. However, some data have been found to slightly exceed the expected normal range for thorium-232 (60% of samples) and potassium-40 (20% of samples). Since there is no handling of those isotopes in the site or others that could

  12. HI-resolution gamma spectrometry measurements of U-238, TH-232, K-40 and CS-137 concentrations in soil samples from Capao Island at CTEx

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Luciano S.R.; Oliveira, Celio J.V.; Vilela, Paulo R.T.; Vital, Helio C., E-mail: vital@ctex.eb.br [Centro Tecnologico do Exercito (DDQBN/CTEX), Rio de Janeiro, RJ (Brazil). Div. de Defesa Quimica, Biologica e Nuclear. Secao de Defesa Nuclear

    2013-07-01

    Absolute soil concentrations of U-238, Th-232, K-40 and Cs-137 samples collected from Capao Island have been measured by using Hi-Resolution Gamma HPGe Spectrometry. The area of interest encompasses an embankment in a mangrove swamp in Guaratiba, Rio de Janeiro, where nuclear, chemical and biological defense laboratories of the Brazilian Army Technology Center (CTEx) are located. In order to ensure that no significant environmental impact has resulted from neutron physics experiments performed in a graphite subcritical assembly in addition to the operation of two cesium-driven irradiating facilities, routine monitoring of those isotopes have been regularly performed. A total of eight 250 ml samples of mangrove and embankment soils were extracted from four sites of known coordinates within an area of 300 x 300 m{sup 2} and remained stored for a minimum thirty-day period to allow equilibrium to be reached. Collection and preparation of samples were made according to previously established procedures. High purity germanium detectors were used to obtain high-resolution gamma spectra and counting times were required to exceed 30 hours in order to yield sufficient statistical accuracy. Energy and efficiency calibration curves of the counting system were determined by using the GENIE 2000 software for analysis of the gamma spectrum generated by nine standard sources with a total of 11 peak energies ranging from 0.05 to 1.3 MeV. The results, corrected for background, have been expressed as absolute specific activities. All experiments have been made in the Laboratory for Identification of Radiological Agents (LIAR) at CTEx. No trace of cesium-137 has been found and the measured levels of uranium-238, in the order of 10 Bq/kg, are close to the global mean. However, some data have been found to slightly exceed the expected normal range for thorium-232 (60% of samples) and potassium-40 (20% of samples). Since there is no handling of those isotopes in the site or others that

  13. FERMI LARGE AREA TELESCOPE DISCOVERY OF GeV GAMMA-RAY EMISSION FROM THE VICINITY OF SNR W44

    Energy Technology Data Exchange (ETDEWEB)

    Uchiyama, Yasunobu; Funk, Stefan; Katsuta, Junichiro [SLAC National Accelerator Laboratory, 2575 Sand Hill Road M/S 29, Menlo Park, CA 94025 (United States); Katagiri, Hideaki [College of Science, Ibaraki University, 2-1-1, Bunkyo, Mito 310-8512 (Japan); Lemoine-Goumard, Marianne [Centre d' Etudes Nucleaires de Bordeaux Gradignan, Universite Bordeaux 1, CNRS/IN2p3, 33175 Gradignan (France); Tajima, Hiroyasu; Tanaka, Takaaki [Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, CA 94305 (United States); Torres, Diego F., E-mail: uchiyama@slac.stanford.edu [Institut de Ciencies de l' Espai (IEEE-CSIC), Campus UAB, 08193 Barcelona (Spain)

    2012-04-20

    We report the detection of GeV {gamma}-ray emission from the molecular cloud complex that surrounds the supernova remnant (SNR) W44 using the Large Area Telescope on board Fermi. While the previously reported {gamma}-ray emission from SNR W44 is likely to arise from the dense radio-emitting filaments within the remnant, the {gamma}-ray emission that appears to come from the surrounding molecular cloud complex can be ascribed to the cosmic rays (CRs) that have escaped from W44. The non-detection of synchrotron radio emission associated with the molecular cloud complex suggests the decay of {pi}{sup 0} mesons produced in hadronic collisions as the {gamma}-ray emission mechanism. The total kinetic energy channeled into the escaping CRs is estimated to be W{sub esc} {approx} (0.3-3) Multiplication-Sign 10{sup 50} erg, in broad agreement with the conjecture that SNRs are the main sources of Galactic CRs.

  14. Bursts of the Crab Nebula gamma-ray emission at high and ultra-high energies

    Directory of Open Access Journals (Sweden)

    Lidvansky A.S.

    2017-01-01

    Full Text Available Characteristics of the flares of gamma rays detected from the Crab Nebula by the AGILE and Fermi-LAT satellite instruments are compared with those of a gamma ray burst recorded by several air shower arrays on February 23, 1989 and with one recent observation made by the ARGO-YBJ array. It is demonstrated that though pulsar-periodicity and energy spectra of emissions at 100 MeV (satellite gamma ray telescopes and 100 TeV (EAS arrays are different, their time structures seem to be similar. Moreover, maybe the difference between “flares” and “waves” recently found in the Crab Nebula emission by the AGILE team also exists at ultra-high energies.

  15. Effect of gamma irradiation on insecticides of grains and storage raw-materia

    International Nuclear Information System (INIS)

    Manco, E.A.C.

    1987-12-01

    To study the effect of gamma irradiation on deltametrina, malathion and fenitrothion, the saturated filter paper technique was used. The filter paper, saturated with the products, was submitted to increasing doses of gamma radiation - 10, 20 and 40 kGu at a 12.76 kGy rate p/h. Adults of Sitophilus zeamais Mots. reared at 25 0 +- 1 0 C and relative humidity of 70 +- 5% were used. The dead rate used and life expectancy was calculated using the best regression as indicator of the degradation factor of the insecticide. It was noted that gamma radiation degraded deltametrina and fenitrothion, the latter more markedly at a 40 kGy dose. Gamma radiation had no effect on malathion and the insects submitted to it showed a life expectancy smaller than the controls. (author) [pt

  16. /sup 137/Cs and /sup 40/K in the flesh of fish of the Indian Ocean and the Straits of Malacca

    Energy Technology Data Exchange (ETDEWEB)

    Lowe, B G [Link Systems Ltd., High Wycombe (UK)

    1979-06-01

    The flesh of fish obtained from fishing industries based in Penang was dried and analyses for /sup 137/Cs and /sup 40/K concentration by gamma-ray spectrometry. Results for tuna, bluefin, round scad, prawns and anchovy are listed. Values of /sup 137/Cs concentration in the larger fish were very similar, about 9pCi/wet kg. /sup 40/K values varied between 0.6 and 3.9 nCi/wet kg with an average of 3.1 +- 0.3 nCi/wet kg for tuna. Results are compared with those reported for fish caught in other areas. The highest value of /sup 137/Cs activity found represents less than 0.4% of the value determined for natural /sup 40/K.

  17. High energy {gamma} emission in the spontaneous fission of {sup 252}Cf; Emission {gamma} de grande energie dans la fission spontanee de {sup 252}Cf

    Energy Technology Data Exchange (ETDEWEB)

    Badimon, C.; Barreau, G.; Doan, T.P.; Pedemay, G. [Centre d`Etudes Nucleaires, Bordeaux-1 Univ., 33 Gradignan (France); Gautherin, C.; Houry, M.; Korten, W.; Le Coz, Y.; Lucas, R.; Thiesen, Ch. [Dept. d`Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l`Instrumentation Associee, CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France); Belier, G.; Meot, M.V. [CEA Centre d`Etudes de Bruyeres-le-Chatel, 91 (France); Astier, A.; Ducroux, L.; Meyer, M.; Redon, N. [Inst.de Physique Nucleaire, Lyon-1 Univ., 69 - Villeurbanne (France)

    1997-06-01

    The prompt {gamma} emission in the spontaneous fission of {sup 252}Cf is characterized by an energy spectrum which extends up to 20 MeV. It was established that the spectrum presents in the neighbourhood of symmetric fission an intensity bump in the 3-8 MeV {gamma} energy interval. The origin of this phenomenon is still not well understood, so that it was found interesting to carry out new measurements. The spectrum of the {gamma} rays emitted in spontaneous fission of {sup 252}Cf has been measurement in the EUROGAM II multidetector using photovoltaic cells to detect fragments. The aim of the experiment was to investigate the {gamma} yield enhancement which appears for mass fragment ratio near 132/120. This enhancement was found to be composed of two peaks located at 4 MeV and 5.5 MeV respectively. The results obtained confirm the intensity bound in the 3-8 MeV region but this augmentation reaches the maximum when the heavy fragment is near the mass 132. Beyond mass 140 the phenomenon diminish and the {gamma} spectrum regains the behaviour expected for a statistic emission. The additional structure at 5.5 MeV does not vary with excitation energy while the excitation function of the 4 MeV structure is more structured and presents a maximum when the excitation energy is near 8 MeV. It is likely that all or part of this observed phenomenon is due to a particular excitation mode of this isotope associated for instance with a low energy dipole resonance. A theoretical study of this collective effect is under way 3 refs.

  18. Measurement of the Shape of the Optical-IR Spectrum of Prompt Emission from Gamma-Ray Bursts

    Science.gov (United States)

    Grossan, Bruce; Kistaubayev, M.; Smoot, G.; Scherr, L.

    2017-06-01

    While the afterglow phase of gamma-ray bursts (GRBs) has been extensively measured, detections of prompt emission (i.e. during bright X-gamma emission) are more limited. Some prompt optical measurements are regularly made, but these are typically in a single wide band, with limited time resolution, and no measurement of spectral shape. Some models predict a synchrotron self-absorption spectral break somewhere in the IR-optical region. Measurement of the absorption frequency would give extensive information on each burst, including the electron Lorentz factor, the radius of emission, and more (Shen & Zhang 2008). Thus far the best prompt observations have been explained invoking a variety of models, but often with a non-unique interpretation. To understand this apparently heterogeneous behavior, and to reduce the number of possible models, it is critical to add data on the optical - IR spectral shape.Long GRB prompt X-gamma emission typically lasts ~40-80 s. The Swift BAT instrument rapidly measures GRB positions to within a few arc minutes and communicates them via the internet within a few seconds. We have measured the time for a fast-moving D=700 mm telescope to point and settle to be less than 9 s anywhere on the observable sky. Therefore, the majority of prompt optical-IR emission can be measured responding to BAT positions with this telescope. In this presentation, we describe our observing and science programs, and give our design for the Burst Simultaneous Three-channel Instrument (BSTI), which uses dichroics to send eparate bands to 3 cameras. Two EMCCD cameras, give high-time resolution in B and V; a third camera with a HgCdTe sensor covers H band, allowing us to study extinguished bursts. For a total exposure time of 10 s, we find a 5 sigma sensitivity of 21.3 and 20.3 mag in B and R for 1" seeing and Kitt Peak sky brightness, much fainter than typical previous prompt detections. We estimate 5 sigma H-band sensitivity for an IR optimized telescope to be

  19. Counting efficiency for radionuclides decaying by beta and gamma-ray emission; Calculo de la eficiencia de recuento de nucleidos que experimentan desintegracion beta y desexcitacion gamma simple

    Energy Technology Data Exchange (ETDEWEB)

    Grau, A.; Garcia-Torano, E.

    1988-07-01

    In this paper, counting efficiency vs figure of merit for beta and gamma-ray emitters has been computed. It is assumed that the decay scheme has only a gamma level and the beta-ray emission may be coincident with the gamma-rays or the internal-conversion electrons. The radionuclides tabulated are: 20 {sub 0}, 20{sub p}, 28{sub A}l, 35{sub p}, 41{sub A}r, 42{sub K}, 47{sub S}e, 62{sub F}e, 66{sub C}u, 81{sub G}e, 86{sub B}b, 108{sub R}u, 112{sub p}d, 121{sub S}n(Ni), 122{sub I}n, 129{sub I}, 141{sub C}e 171{sub T}m, 194{sub O}s, 2O3{sub H}g, 205{sub H}g, 210{sub p}b, 225{sub R}a, 142{sub p}r, 151{sub S}m, 244{sub A}m(m). It has been assumed that the liquid is a toluene based scintillator solution in standard glass vials containing 10 cm''3. (Author) 8 refs.

  20. Potential radionuclide emissions from stacks on the Hanford site, Part 2: Dose assessment methodology using portable low-resolution gamma spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Barnett, J.M. [Westinghouse Hanford Company, Richland, WA (United States)

    1995-02-01

    In September 1992, the Westinghouse Hanford Company began developing an in situ measurement method to assess gamma radiation emanating from high-efficiency particulate air filters using portable low-resolution gamma spectroscopy. The purpose of the new method was to assess radioactive exhaust stack air emissions from empirical data rather than from theoretical models and to determine the potential unabated dose to an offsite theoretical maximally exposed individual. In accordance with Title 40, Code of Federal Regulations, Part 61, Subpart H, {open_quotes}National Emission Standards for Hazardous Air Pollutants{close_quotes}, stacks that have the potential to emit {ge} 1 {mu}Sv y{sup {minus}1} (0.1 mrem y{sup {minus}1}) to the maximally exposed individual are considered {open_quotes}major{close_quotes} and must meet the continuous monitoring requirements. After the method was tested and verified, the U.S. Environmental Protection Agency, Region 10, approved its use in June 1993. Of the 125 stacks operated by the Westinghouse Hanford Company, 22 were targeted for evaluation by this method, and 15 were assessed. (The method could not be applied at seven stacks because of excessive background radiation or because no gamma emitting particles appear in the emission stream.) The most significant result from this study was the redesignation of the T Plant main stack. The stack was assessed as being {open_quotes}minor{close_quotes}, and it now only requires periodic confirmatory measurements and meets federally imposed sampling requirements.

  1. Development of small-diameter lead-glass-tube matrices for gamma-ray conversion in positron emission tomography

    International Nuclear Information System (INIS)

    Schwartz, G.M.

    1985-05-01

    A gamma-ray converter for a multiwire proportional chamber (MWPC) positron emission tomograph is described. The converter is made of small-diameter (0.48 mm inner diameter, 0.06 mm wall thickness) lead-oxide-glass tubes fused to form a honeycomb matrix. The surfaces of the tubes are reduced in a hydrogen atmosphere to provide the drift electric field for detection of the conversion electrons. The detection efficiency for a 10 mm thick converter is 6.65%, with a time resolution of 160 ns (FWHM). A scheme which will improve the spatial resolution of the tomograph by use of the self quenching streamer mode of chamber operation is described. Details of construction of the converters and the MWPC are presented, as well as the design performance of a high spatial resolution positron emission tomograph (HISPET). 40 refs., 22 figs

  2. A possible origin of gamma rays from the Fermi Bubbles

    Science.gov (United States)

    Thoudam, Satyendra

    2014-11-01

    One of the most exciting discoveries of recent years is a pair of gigantic gamma-ray emission regions, the so-called Fermi bubbles, above and below the Galactic center. The bubbles, discovered by the Fermi space telescope, extend up to ∼50° in Galactic latitude and are ∼40° wide in Galactic longitude. The gamma-ray emission is also found to correlate with radio, microwave and X-rays emission. The origin of the bubbles and the associated non-thermal emissions are still not clearly understood. Possible explanations for the non-thermal emission include cosmic-ray injection from the Galactic center by high speed Galactic winds/jets, acceleration by multiple shocks or plasma turbulence present inside the bubbles, and acceleration by strong shock waves associated with the expansion of the bubbles. In this paper, I will discuss the possibility that the gamma-ray emission is produced by the injection of Galactic cosmic-rays mainly protons during their diffusive propagation through the Galaxy. The protons interact with the bubble plasma producing π°-decay gamma rays, while at the same time, radio and microwave synchrotron emissions are produced by the secondary electrons/positrons resulting from the π± decays.

  3. A possible origin of gamma rays from the Fermi Bubbles

    International Nuclear Information System (INIS)

    Thoudam, Satyendra

    2014-01-01

    One of the most exciting discoveries of recent years is a pair of gigantic gamma-ray emission regions, the so-called Fermi bubbles, above and below the Galactic center. The bubbles, discovered by the Fermi space telescope, extend up to ∼50 ° in Galactic latitude and are ∼40 ° wide in Galactic longitude. The gamma-ray emission is also found to correlate with radio, microwave and X-rays emission. The origin of the bubbles and the associated non-thermal emissions are still not clearly understood. Possible explanations for the non-thermal emission include cosmic-ray injection from the Galactic center by high speed Galactic winds/jets, acceleration by multiple shocks or plasma turbulence present inside the bubbles, and acceleration by strong shock waves associated with the expansion of the bubbles. In this paper, I will discuss the possibility that the gamma-ray emission is produced by the injection of Galactic cosmic-rays mainly protons during their diffusive propagation through the Galaxy. The protons interact with the bubble plasma producing π ° -decay gamma rays, while at the same time, radio and microwave synchrotron emissions are produced by the secondary electrons/positrons resulting from the π ± decays

  4. Effects of chemical sensitizers on gamma radiation processing of ...

    African Journals Online (AJOL)

    The potential of gamma radiation processing in cross-linking natural rubber latex (NRL) for production of dipped goods has been studied. NRL produced in Ghana was irradiated to 10, 20, 30, 40 and 50 kGy, respectively, in a Gamma Chamber of dose rate 0.65 kGy/h. Irradiation of the NRL was also carried out in the ...

  5. Secondary electron emission from metals irradiated by 0.4-3 MeV gamma-quanta

    International Nuclear Information System (INIS)

    Grudskij, M.Ya.; Malyshenkov, A.V.; Smirnov, V.V.

    1975-01-01

    Experimental and calculational data were considered on the secondary electron emission outgoing from metal targets of an equilibrium thickness irradiated by gamma-quanta fluxes with the energies from 0.4 to 3 MeV. New experimental data are presented. Characteristics of emission were measured by two methods: by magnetic spectrometers with a transverse magnetic field, and by means of an electrometric device with using radioisotopic gamma-sources of 198 Au, 137 Cs, 60 Co and 24 Na. The dependence of the electron emission on the atomic number of the target material was studied. For this purpose the parameters of emissions outgoing from Al-, Cu-, Cd-, Pb- and Au-targets were measured. The advantages and shortcomings of the known methods of calculating the second electron emission were discussed. The obtained experimental and calculational results on studying electrons were compared with those known from literature, and possible sources of systematic errors were discussed

  6. 226Ra, 232Th and 40K analysis in water samples from Assiut, Egypt

    International Nuclear Information System (INIS)

    El-Gamal, H.; Abdel Mageed, A.I.; El-Attar, A.L; Abdel Hamid, M.

    2013-01-01

    The activity concentrations of 226 Ra, 232 Th and 40 K were determined in water samples, using 2”x 2” NaI(Tl) scintillation detector. Water activity ranges from 0.07 to 0.59 Bq L−1 for 226 Ra, 0.05 to 0.37 Bq L−1 for 232 Th and 3.25 to 8.72 Bq L−1 for 40 K with mean values of 2.64, 2.22 and 119.50 Bq L−1, respectively. As far as the measured gamma radionuclides is concerned, the mean annual effective doses for all analyzed samples of water are in the range of 0.02–0.08, 0.03-0.17 and 0.03-0.10 mSv yr -1 for infants, children and adults, respectively, all being lower than the reference level of the committed effective dose recommended by the WHO.

  7. Estimation of loss of 40K during different cooking procedures of rice

    International Nuclear Information System (INIS)

    Aparna, K.R.; Karunakara, N.; Selvi, B.S.; Joshi, R.M.; Ravi, P.M.

    2008-01-01

    The present regulations on toxic element intake is based on the assumption that 100% of the toxin present in raw materials such as cereals, pulses and vegetables are taken up by human being through ingestion. This is not realistic because of the fact that many of the toxic materials are lost during various cooking processes such as washing, peeling, etc. In order to take into account the loss of radionuclide during cooking, some of the regulatory agencies use Retention Factors (F r ) and Processing Efficiencies (P e ) for impact assessment. In Karnataka, rice is the major dietary item and the cooking procedure varies from place to place. This paper presents the results of estimation of F r and P e for two types of cooking procedures of raw rice and boiled rice commonly used in Karnataka. 40 K is used as tracer in the present study because of its natural abundance, easy detection by gamma ray spectrometry and chemical resemblance with 137 Cs. The concentration of 40 K in raw and processed food was estimated by gamma ray spectrometry using an HPGe detector and F r and P e were estimated. The value of F r ranges from 0.6 to 0.85 and 0.41 to 0.72 for raw rice and boiled rice respectively. Similarly, the values of P e vary from 0.9 to 1 for both types of rice. In the absence of site-specific data for 137 Cs, this data can be used for calculation of 137 Cs in cooked rice during accidental conditions of nuclear installations. (author)

  8. High-energy gamma-ray emission from the Galactic Center

    DEFF Research Database (Denmark)

    Mayer-Hasselwander, H.A.; Bertsch, D.L.; Dingus, B.L.

    1998-01-01

    '. A compact sources model hints at an origin in pulsars. While the spectrum suggests middle-aged pulsars like Vela, too many are required to produce the observed flux. The only detected very young pulsar, the Crab pulsar, has an incompatible spectrum. However, it is not proven that the Crab spectrum...... is characteristic for all young pulsars: thus, a single or a few very young pulsars (at the GC not detectable in radio emission), provided their gamma-ray emission is larger than that of the Crab pulsar by a factor of 13, are likely candidates. Alternatively, more exotic scenarios, related to the postulated central...

  9. The Distributions of the Radionuclides Ra-226, Th-232 and K-40 in Various Parts of The Alfalfa Plant

    International Nuclear Information System (INIS)

    Salahel Din, K.; Harb, S.; Abbady, A.; Saad, N.

    2011-01-01

    The distribution of naturally occurring Ra-226, Th-232 and K-40 in different part of alfalfa plant from two different soils of Qena (South Valley University and Qena governorate farms) was studied under natural field conditions. Sixty two samples (alfalfa plant and its soil) were taken from nine sites inside farms. The samples were analyzed for their Ra-226, Th-232 and K-40 activity concentrations using gamma ray spectrometer consists of 3 x 3 NaI (Tl). The daily intakes of these radioisotopes by calves, milking cattle and sheep were calculated by multiplying concentrations in alfalfa and the daily consumption rates of these plants.

  10. Ca II H and K emission from late-type stars

    International Nuclear Information System (INIS)

    Middlekoop, F.

    1982-01-01

    This thesis is based on a study of the Ca II H and K emission features of late main-sequence stars. In Chapter II it is shown that rotation periods can be determined from a modulation in the Ca II H and K signal for many stars in a broad range of spectral types. In Chapter III it is shown that a clear correlation exists between Ca II H and K emission and rotational velocity in active main-sequence stars. There is an indication for a (probably colour-dependent) critical velocity at which the Ca II H and K emission suddenly drops. Chapter IV discusses the dependence of Ca II H and K emission on the rotation rate for evolved stars. (Auth./C.F.)

  11. Measurement of partial widths and search for direct CP violation in D0 meson decays to K-K+ and pi-pi+.

    Science.gov (United States)

    Acosta, D; Affolder, T; Akimoto, T; Albrow, M G; Ambrose, D; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arisawa, T; Arguin, J-F; Artikov, A; Ashmanskas, W; Attal, A; Azfar, F; Azzi-Bacchetta, P; Bacchetta, N; Bachacou, H; Badgett, W; Barbaro-Galtieri, A; Barker, G J; Barnes, V E; Barnett, B A; Baroiant, S; Barone, M; Bauer, G; Bedeschi, F; Behari, S; Belforte, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Bhatti, A; Binkley, M; Bisello, D; Bishai, M; Blair, R E; Blocker, C; Bloom, K; Blumenfeld, B; Bocci, A; Bodek, A; Bolla, G; Bolshov, A; Booth, P S L; Bortoletto, D; Boudreau, J; Bourov, S; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Burkett, K; Busetto, G; Bussey, P; Byrum, K L; Cabrera, S; Calafiura, P; Campanelli, M; Campbell, M; Canepa, A; Casarsa, M; Carlsmith, D; Carron, S; Carosi, R; Cavalli-Sforza, M; Castro, A; Catastini, P; Cauz, D; Cerri, A; Cerri, C; Cerrito, L; Chapman, J; Chen, C; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chu, M L; Chuang, S; Chung, J Y; Chung, W-H; Chung, Y S; Ciobanu, C I; Ciocci, M A; Clark, A G; Clark, D; Coca, M; Connolly, A; Convery, M; Conway, J; Cooper, B; Cordelli, M; Cortiana, G; Cranshaw, J; Cuevas, J; Culbertson, R; Currat, C; Cyr, D; Dagenhart, D; Da Ronco, S; D'Auria, S; de Barbaro, P; De Cecco, S; De Lentdecker, G; Dell'agnello, S; Dell'orso, M; Demers, S; Demortier, L; Deninno, M; De Pedis, D; Derwent, P F; Dionisi, C; Dittmann, J R; Doksus, P; Dominguez, A; Donati, S; Donega, M; Donini, J; D'Onofrio, M; Dorigo, T; Drollinger, V; Ebina, K; Eddy, N; Ely, R; Erbacher, R; Erdmann, M; Errede, D; Errede, S; Eusebi, R; Fang, H-C; Farrington, S; Fedorko, I; Feild, R G; Feindt, M; Fernandez, J P; Ferretti, C; Field, R D; Fiori, I; Flanagan, G; Flaugher, B; Flores-Castillo, L R; Foland, A; Forrester, S; Foster, G W; Franklin, M; Freeman, J; Frisch, H; Fujii, Y; Furic, I; Gajjar, A; Gallas, A; Galyardt, J; Gallinaro, M; Garcia-Sciveres, M; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D W; Gerchtein, E; Giagu, S; Giannetti, P; Gibson, A; Gibson, K; Ginsburg, C; Giolo, K; Giordani, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, D; Goldstein, J; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Gotra, Y; Goulianos, K; Gresele, A; Griffiths, M; Grosso-Pilcher, C; Guenther, M; Guimaraes da Costa, J; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Handler, R; Happacher, F; Hara, K; Hare, M; Harr, R F; Harris, R M; Hartmann, F; Hatakeyama, K; Hauser, J; Hays, C; Hayward, H; Heider, E; Heinemann, B; Heinrich, J; Hennecke, M; Herndon, M; Hill, C; Hirschbuehl, D; Hocker, A; Hoffman, K D; Holloway, A; Hou, S; Houlden, M A; Huffman, B T; Huang, Y; Hughes, R E; Huston, J; Ikado, K; Incandela, J; Introzzi, G; Iori, M; Ishizawa, Y; Issever, C; Ivanov, A; Iwata, Y; Iyutin, B; James, E; Jang, D; Jarrell, J; Jeans, D; Jensen, H; Jeon, E J; Jones, M; Joo, K K; Jun, S; Junk, T; Kamon, T; Kang, J; Karagoz Unel, M; Karchin, P E; Kartal, S; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, M S; Kim, S B; Kim, S H; Kim, T H; Kim, Y K; King, B T; Kirby, M; Kirsch, L; Klimenko, S; Knuteson, B; Ko, B R; Kobayashi, H; Koehn, P; Kong, D J; Kondo, K; Konigsberg, J; Kordas, K; Korn, A; Korytov, A; Kotelnikov, K; Kotwal, A V; Kovalev, A; Kraus, J; Kravchenko, I; Kreymer, A; Kroll, J; Kruse, M; Krutelyov, V; Kuhlmann, S E; Kuznetsova, N; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, J; Lancaster, M; Lander, R; Lannon, K; Lath, A; Latino, G; Lauhakangas, R; Lazzizzera, I; Le, Y; Lecci, C; Lecompte, T; Lee, J; Lee, J; Lee, S W; Leonardo, N; Leone, S; Lewis, J D; Li, K; Lin, C; Lin, C S; Lindgren, M; Liss, T M; Litvintsev, D O; Liu, T; Liu, Y; Lockyer, N S; Loginov, A; Loreti, M; Loverre, P; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lyons, L; Lys, J; Lysak, R; Macqueen, D; Madrak, R; Maeshima, K; Maksimovic, P; Malferrari, L; Manca, G; Marginean, R; Martin, M; Martin, A; Martin, V; Martínez, M; Maruyama, T; Matsunaga, H; Mattson, M; Mazzanti, P; McFarland, K S; McGivern, D; McIntyre, P M; McNamara, P; Ncnulty, R; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miller, L; Miller, R; Miller, J S; Miquel, R; Miscetti, S; Mitselmakher, G; Miyamoto, A; Miyazaki, Y; Moggi, N; Mohr, B; Moore, R; Morello, M; Mukherjee, A; Mulhearn, M; Muller, T; Mumford, R; Munar, A; Murat, P; Nachtman, J; Nahn, S; Nakamura, I; Nakano, I; Napier, A; Napora, R; Naumov, D; Necula, V; Niell, F; Nielsen, J; Nelson, C; Nelson, T; Neu, C; Neubauer, M S; Newman-Holmes, C; Nicollerat, A-S; Nigmanov, T; Nodulman, L; Norniella, O; Oesterberg, K; Ogawa, T; Oh, S H; Oh, Y D; Ohsugi, T; Okusawa, T; Oldeman, R; Orava, R; Orejudos, W; Pagliarone, C; Palmonari, F; Paoletti, R; Papadimitriou, V; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Pauly, T; Paus, C; Pellett, D; Penzo, A; Phillips, T J; Piacentino, G; Piedra, J; Pitts, K T; Plager, C; Pompos, A; Pondrom, L; Pope, G; Poukhov, O; Prakoshyn, F; Pratt, T; Pronko, A; Proudfoot, J; Ptohos, F; Punzi, G; Rademacker, J; Rakitine, A; Rappoccio, S; Ratnikov, F; Ray, H; Reichold, A; Reisert, B; Rekovic, V; Renton, P; Rescigno, M; Rimondi, F; Rinnert, K; Ristori, L; Robertson, W J; Robson, A; Rodrigo, T; Rolli, S; Rosenson, L; Roser, R; Rossin, R; Rott, C; Russ, J; Ruiz, A; Ryan, D; Saarikko, H; Safonov, A; St Denis, R; Sakumoto, W K; Salamanna, G; Saltzberg, D; Sanchez, C; Sansoni, A; Santi, L; Sarkar, S; Sato, K; Savard, P; Savoy-Navarro, A; Schemitz, P; Schlabach, P; Schmidt, E E; Schmidt, M P; Schmitt, M; Scodellaro, L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semeria, F; Sexton-Kennedy, L; Sfiligoi, I; Shapiro, M D; Shears, T; Shepard, P F; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Siegrist, J; Siket, M; Sill, A; Sinervo, P; Sisakyan, A; Skiba, A; Slaughter, A J; Sliwa, K; Smirnov, D; Smith, J R; Snider, F D; Snihur, R; Somalwar, S V; Spalding, J; Spezziga, M; Spiegel, L; Spinella, F; Spiropulu, M; Squillacioti, P; Stadie, H; Stefanini, A; Stelzer, B; Stelzer-Chilton, O; Strologas, J; Stuart, D; Sukhanov, A; Sumorok, K; Sun, H; Suzuki, T; Taffard, A; Tafirout, R; Takach, S F; Takano, H; Takashima, R; Takeuchi, Y; Takikawa, K; Tanaka, M; Tanaka, R; Tanimoto, N; Tapprogge, S; Tecchio, M; Teng, P K; Terashi, K; Tesarek, R J; Tether, S; Thom, J; Thompson, A S; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tollefson, K; Tomura, T; Tonelli, D; Tönnesmann, M; Torre, S; Torretta, D; Trischuk, W; Tseng, J; Tsuchiya, R; Tsuno, S; Tsybychev, D; Turini, N; Turner, M; Ukegawa, F; Unverhau, T; Uozumi, S; Usynin, D; Vacavant, L; Vaiciulis, A; Varganov, A; Vataga, E; Vejcik, S; Velev, G; Veramendi, G; Vickey, T; Vidal, R; Vila, I; Vilar, R; Volobouev, I; von der Mey, M; Wagner, P; Wagner, R G; Wagner, R L; Wagner, W; Wallny, R; Walter, T; Yamashita, T; Yamamoto, K; Wan, Z; Wang, M J; Wang, S M; Warburton, A; Ward, B; Waschke, S; Waters, D; Watts, T; Weber, M; Wester, W C; Whitehouse, B; Wicklund, A B; Wicklund, E; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolter, M; Worcester, M; Worm, S; Wright, T; Wu, X; Würthwein, F; Wyatt, A; Yagil, A; Yang, U K; Yao, W; Yeh, G P; Yi, K; Yoh, J; Yoon, P; Yorita, K; Yoshida, T; Yu, I; Yu, S; Yu, Z; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zetti, F; Zhou, J; Zsenei, A; Zucchelli, S

    2005-04-01

    We present a measurement of relative partial widths and decay rate CP asymmetries in K-K+ and pi(-)pi(+) decays of D0 mesons produced in pp collisions at sqrt[s]=1.96 TeV. We use a sample of 2x10(5) D(*+)-->D0pi(+) (and charge conjugate) decays with the D0 decaying to K-pi(+), K-K+, and pi(-)pi(+), corresponding to 123 pb(-1) of data collected by the Collider Detector at Fermilab II experiment at the Fermilab Tevatron collider. No significant direct CP violation is observed. We measure Gamma(D0-->K-K+)/Gamma(D0-->K-pi(+))=0.0992+/-0.0011+/-0.0012, Gamma(D0-->pi(-)pi(+))/Gamma(D0-->K-pi(+))=0.035 94+/-0.000 54+/-0.000 40, A(CP)(K-K+)=(2.0+/-1.2+/-0.6)%, and A(CP)(pi(-)pi(+))=(1.0+/-1.3+/-0.6)%, where, in all cases, the first uncertainty is statistical and the second is systematic.

  12. Realization of a gamma emission tomography by a servo-controlled camera and bed

    International Nuclear Information System (INIS)

    Parmentier, M.; Gunzman, D.; Bidet, R.

    1979-01-01

    A gamma-camera and a whole-body bed were connected to a minicomputer which controlled automatically their movements. By combining horizontal displacement of the bed with vertical displacement and rotation of the camera we were able to obtain the equivalent of camera rotation around the bed. This method provides an inexpensive way of realizing gamma emission tomography [fr

  13. Constraining the High-Energy Emission from Gamma-Ray Bursts with Fermi

    Science.gov (United States)

    Gehrels, Neil; Harding, A. K.; Hays, E.; Racusin, J. L.; Sonbas, E.; Stamatikos, M.; Guirec, S.

    2012-01-01

    We examine 288 GRBs detected by the Fermi Gamma-ray Space Telescope's Gamma-ray Burst Monitor (GBM) that fell within the field-of-view of Fermi's Large Area Telescope (LAT) during the first 2.5 years of observations, which showed no evidence for emission above 100 MeV. We report the photon flux upper limits in the 0.1-10 GeV range during the prompt emission phase as well as for fixed 30 s and 100 s integrations starting from the trigger time for each burst. We compare these limits with the fluxes that would be expected from extrapolations of spectral fits presented in the first GBM spectral catalog and infer that roughly half of the GBM-detected bursts either require spectral breaks between the GBM and LAT energy bands or have intrinsically steeper spectra above the peak of the nuF(sub v) spectra (E(sub pk)). In order to distinguish between these two scenarios, we perform joint GBM and LAT spectral fits to the 30 brightest GBM-detected bursts and find that a majority of these bursts are indeed softer above E(sub pk) than would be inferred from fitting the GBM data alone. Approximately 20% of this spectroscopic subsample show statistically significant evidence for a cut-off in their high-energy spectra, which if assumed to be due to gamma gamma attenuation, places limits on the maximum Lorentz factor associated with the relativistic outflow producing this emission. All of these latter bursts have maximum Lorentz factor estimates that are well below the minimum Lorentz factors calculated for LAT-detected GRBs, revealing a wide distribution in the bulk Lorentz factor of GRB outflows and indicating that LAT-detected bursts may represent the high end of this distribution.

  14. 40 CFR 76.11 - Emissions averaging.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Emissions averaging. 76.11 Section 76.11 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.11 Emissions averaging. (a) General...

  15. Classification of JET Neutron and Gamma Emissivity Profiles

    Science.gov (United States)

    Craciunescu, T.; Murari, A.; Kiptily, V.; Vega, J.; Contributors, JET

    2016-05-01

    In thermonuclear plasmas, emission tomography uses integrated measurements along lines of sight (LOS) to determine the two-dimensional (2-D) spatial distribution of the volume emission intensity. Due to the availability of only a limited number views and to the coarse sampling of the LOS, the tomographic inversion is a limited data set problem. Several techniques have been developed for tomographic reconstruction of the 2-D gamma and neutron emissivity on JET. In specific experimental conditions the availability of LOSs is restricted to a single view. In this case an explicit reconstruction of the emissivity profile is no longer possible. However, machine learning classification methods can be used in order to derive the type of the distribution. In the present approach the classification is developed using the theory of belief functions which provide the support to fuse the results of independent clustering and supervised classification. The method allows to represent the uncertainty of the results provided by different independent techniques, to combine them and to manage possible conflicts.

  16. High-energy gamma-ray emission from solar flares: Constraining the accelerated proton spectrum

    Science.gov (United States)

    Alexander, David; Dunphy, Philip P.; Mackinnon, Alexander L.

    1994-01-01

    Using a multi-component model to describe the gamma-ray emission, we investigate the flares of December 16, 1988 and March 6, 1989 which exhibited unambiguous evidence of neutral pion decay. The observations are then combined with theoretical calculations of pion production to constrain the accelerated proton spectra. The detection of pi(sup 0) emission alone can indicate much about the energy distribution and spectral variation of the protons accelerated to pion producing energies. Here both the intensity and detailed spectral shape of the Doppler-broadened pi(sup 0) decay feature are used to determine the spectral form of the accelerated proton energy distribution. The Doppler width of this gamma-ray emission provides a unique diagnostic of the spectral shape at high energies, independent of any normalisation. To our knowledge, this is the first time that this diagnostic has been used to constrain the proton spectra. The form of the energetic proton distribution is found to be severely limited by the observed intensity and Doppler width of the pi(sup 0) decay emission, demonstrating effectively the diagnostic capabilities of the pi(sup 0) decay gamma-rays. The spectral index derived from the gamma-ray intensity is found to be much harder than that derived from the Doppler width. To reconcile this apparent discrepancy we investigate the effects of introducing a high-energy cut-off in the accelerated proton distribution. With cut-off energies of around 0.5-0.8 GeV and relatively hard spectra, the observed intensities and broadening can be reproduced with a single energetic proton distribution above the pion production threshold.

  17. Use of prompt gamma emissions from polyethylene to estimate neutron ambient dose equivalent

    Energy Technology Data Exchange (ETDEWEB)

    Priyada, P.; Sarkar, P.K., E-mail: pradip.sarkar@manipal.edu

    2015-06-11

    The possibility of using measured prompt gamma emissions from polyethylene to estimate neutron ambient dose equivalent is explored theoretically. Monte Carlo simulations have been carried out using the FLUKA code to calculate the response of a high density polyethylene cylinder to emit prompt gammas from interaction of neutrons with the nuclei of hydrogen and carbon present in polyethylene. The neutron energy dependent responses of hydrogen and carbon nuclei are combined appropriately to match the energy dependent neutron fluence to ambient dose equivalent conversion coefficients. The proposed method is tested initially with simulated spectra and then validated using experimental measurements with an Am–Be neutron source. Experimental measurements and theoretical simulations have established the feasibility of estimating neutron ambient dose equivalent using measured neutron induced prompt gammas emitted from polyethylene with an overestimation of neutron dose at very low energies. - Highlights: • A new method for estimating H{sup ⁎}(10) using prompt gamma emissions from HDPE. • Linear combination of 2.2 MeV and 4.4 MeV gamma intensities approximates DCC (ICRP). • Feasibility of the method was established theoretically and experimentally. • The response of the present technique is very similar to that of the rem meters.

  18. Gamma Spectrometric Determination of U, Th, K and Some Geochemical Applications

    International Nuclear Information System (INIS)

    Dodona, A.; Tashko, A.

    2001-01-01

    The application of 'in situ' gamma-spectrometric method (''infinite'' environment), made possible the simultanious determination of U, Th and K. 4 channel gamma-spectrometric analyser with NaI(TI) scintilation counter crystal detector (103 cm 3 φ=50x50mm) was used to determin U, Th(more than 1-2 ppm) and K (more than 1%) in laboratory conditions. The detector was inserted into a lead camera and calibrated for measurement geometry with vessel of ''Marineli'' type of a 17o cm 3 volume. The study of main factors, which influence in the gamma spectrometric measurements, (the technical, physical, geometrical and time parameters) has been carried out. International standards of U, Th, K and internal monitoring standard samples are used for the calibration. External analytical control has been realized by other radiometric and chemical methods. The detection limits ( 1 ppm Th, 2ppm U and 1% K) and the relative errors (17-20% for 1-10 ppm U, Th and 10-15% for more than 10 ppm U, Th and more than 1% K) guarantee a quantitative analysis that may be used successfully in the geochemical studies. Some geochemical applications, based on the content of Th, U and Th/U ratio in rocks samples that we have we have analyzed with this method, are shown in this paper. U, Th and their ratio are used as trace elements to indicate the differences between the acidic magmatic rocks of Albania (Th/U ratio=2-6 and>10). The bimodal character of Th/U scattering in ignimbrides and monzonites (Korabi zone) shows that in addition to the ''normal'' rocks, there are also some ones enriched with Th, So, the differential analysis of Th, U, and K may be used as geochemical exploration criteria for the radioactive and non-radioactive mineralization, such as REE (Rare Earth Elements), phospghorites, bauxites, placers etc. (authors)

  19. Activity concentrations of 226Ra, 232Th and 40K in brands of fertilisers used in Nigeria

    International Nuclear Information System (INIS)

    Jibiri, N. N.; Fasae, K. P.

    2012-01-01

    The activity concentration of naturally occurring radionuclides 40 K, 226 Ra and 232 Th have been measured in different brands of fertiliser samples sold to farmers in retail markets in six commercial cities in southwestern Nigeria. Gamma ray spectroscopy was employed in the measurements of these radionuclides. The results of measurements showed that the average activity concentration of 40 K in the nitrogen, phosphorus and potassium fertilisers across the cities varied from 3972.0 ±416.9 to 5089.3 ±111.3 Bq kg -1 , 9.9 ±7.3 to 450.6 ±14.3 Bq kg -1 for 226 Ra, while for 232 Th it varied from less than lower limit of detection to 15.1 ±2.8 Bq kg -1 . The activity concentrations of 40 K, 226 Ra and 232 Th in single super phosphate (SSP) fertilisers and phosphate rocks were also determined. However, high activity concentrations of 226 Ra were obtained in the SSP fertiliser and phosphate rocks and in particular, two brands of fertilisers from ITL/TAK and F and C companies. The values of the activity concentration of the radionuclides in the brands of fertilisers used in Nigeria are within the range of values reported in several other countries except 40 K. (authors)

  20. Search for two-photon production of resonances decaying into K anti K and K anti K. pi

    Energy Technology Data Exchange (ETDEWEB)

    Althoff, M; Braunschweig, W; Kirschfink, F J; Martyn, H U; Rosskamp, R; Siebke, H; Wallraff, W; Eisenmann, J; Fischer, H M; Hartmann, H

    1985-11-01

    An analysis of the production of Ksub(s)/sup 0/Ksub(s)/sup 0/ and Ksup(+-)Ksub (s)/sup 0/..pi..sup(-+) by two quasi-real photons is presented. The cross section for ..gamma gamma..->K/sup 0/ anti K/sup 0/, which is given for the ..gamma gamma.. invariant mass range from K anti K threshold to 2.5 GeV, is dominated by the f'(1,525) resonance and an enhancement near the K anti K threshold. Upper limits on the product of the two-photon width times the branching ratio into K anti K pairs are given for THETA(1,700), h(2,030), and zeta(2,220). For exclusive two-photon production of Ksup(+-)Ksub(s)/sup 0/..pi..-+ no significant signal was observed. Upper limits are given on the cross section of ..gamma gamma..->K/sup +/ anti K/sup 0/..pi../sup -/ or K/sup -/K/sup 0/..pi../sup +/ between 1.4 and 3.2 GeV and on the product of the ..gamma gamma.. width times the branching ratio into the Kanti K..pi.. final states for the etasub(c)(2,980) and the iota(1,440), yielding GAMMA(..gamma gamma..->iota(1,440)) . BR(iota(1,440)-> K anti K..pi..) < 2.2keV at 95% C.L.

  1. Gamma irradiation improves the antioxidant activity of Aloe vera (Aloe barbadensis miller) extracts

    International Nuclear Information System (INIS)

    Lee, Eun Mi; Bai, Hyoung-Woo; Lee, Seung Sik; Hong, Sung Hyun; Cho, Jae-Young; Byung, Yeoup Chung

    2012-01-01

    Aloe has been widely used in food products, pharmaceuticals, and cosmetics because of its aromatic and therapeutic properties. In the present study, the ethanolic extracts of aloe gel were gamma-irradiated from 10 to 100 kGy. After gamma irradiation, the color of the ethanolic extracts of aloe gel changed to red; this color persisted up to 40 kGy but disappeared above 50 kGy. Liquid chromatography/mass spectrometry analysis demonstrated the production of a new, unknown compound (m/z=132) after gamma irradiation of the ethanolic extracts of aloe gel. The amount of this unknown compound increased with increasing irradiation up to 80 kGy, and it was degraded at 100 kGy. Interestingly, it was found that gamma irradiation significantly increased the antioxidant activity, as measured by the 1,1-diphenyl-2-picrylhydrazyl-radical scavenging capacity. The antioxidant activity of aloe extract was dramatically increased from 53.9% in the non-irradiated sample to 92.8% in the sample irradiated at 40 kGy. This strong antioxidant activity was retained even at 100 kGy. These results indicate that gamma irradiation of aloe extract can enhance its antioxidant activity through the formation of a new compound. Based on these results, increased antioxidant activity of aloe extracts by gamma rays can be applied to various industries, especially cosmetics, foodstuffs, and pharmaceuticals.

  2. Gamma irradiation improves the antioxidant activity of Aloe vera (Aloe barbadensis miller) extracts

    Science.gov (United States)

    Mi Lee, Eun; Bai, Hyoung-Woo; Sik Lee, Seung; Hyun Hong, Sung; Cho, Jae-Young; Yeoup Chung, Byung

    2012-08-01

    Aloe has been widely used in food products, pharmaceuticals, and cosmetics because of its aromatic and therapeutic properties. In the present study, the ethanolic extracts of aloe gel were gamma-irradiated from 10 to 100 kGy. After gamma irradiation, the color of the ethanolic extracts of aloe gel changed to red; this color persisted up to 40 kGy but disappeared above 50 kGy. Liquid chromatography/mass spectrometry analysis demonstrated the production of a new, unknown compound (m/z=132) after gamma irradiation of the ethanolic extracts of aloe gel. The amount of this unknown compound increased with increasing irradiation up to 80 kGy, and it was degraded at 100 kGy. Interestingly, it was found that gamma irradiation significantly increased the antioxidant activity, as measured by the 1,1-diphenyl-2-picrylhydrazyl-radical scavenging capacity. The antioxidant activity of aloe extract was dramatically increased from 53.9% in the non-irradiated sample to 92.8% in the sample irradiated at 40 kGy. This strong antioxidant activity was retained even at 100 kGy. These results indicate that gamma irradiation of aloe extract can enhance its antioxidant activity through the formation of a new compound. Based on these results, increased antioxidant activity of aloe extracts by gamma rays can be applied to various industries, especially cosmetics, foodstuffs, and pharmaceuticals.

  3. Determination of specific concentrations of {sup 40}K, {sup 238}U and {sup 232}Th in mineral fertilizer samples

    Energy Technology Data Exchange (ETDEWEB)

    Garcez, Ricardo W.D.; Lopes, Jose M.; Silva, Ademir X., E-mail: r.w.o.g@fisica.if.uff.br, E-mail: ademir@nuclear.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Domingues, Alessandro M.; Lima, Marco F. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil)

    2015-07-01

    The use of fertilizer is an established practice worldwide to promote agricultural productivity increased without increasing the planted area, resulting in native forests protection and increase of the food availability. Some kinds of fertilizer have in their chemical composition some radionuclides due the origin of its feedstock, such as {sup 238}U, the {sup 232}Th, and their descendants, beyond {sup 40}K. Knowledge of the radioactivity levels in the environment is great importance to know the gamma radiation dose that the human being is exposed. For identification and quantitation of radionuclides, it was used gamma spectrometry where HPGe detector was used to obtain the spectra, and LabSOCS software for calculating the detection efficiency for each energy. The values of {sup 232}Th specific concentrations ranged from 4.1 to 368.1 Bq.Kg{sup -1}, the values of {sup 238}U specific concentrations ranged from 16.0 to 647.7 Bq.Kg{sup -1} and {sup 40}K specific concentrations ranged from 19.1 to 12713 Bq.Kg{sup -1}. Concentrations of values are consistent with those found in literature. (author)

  4. Production of 147Eu for gamma-ray emission probability measurement

    International Nuclear Information System (INIS)

    Katoh, Keiji; Marnada, Nada; Miyahara, Hiroshi

    2002-01-01

    Gamma-ray emission probability is one of the most important decay parameters of radionuclide and many researchers are paying efforts to improve the certainty of it. The certainties of γ-ray emission probabilities for neutron-rich nuclides are being improved little by little, but the improvements of those for proton-rich nuclides are still insufficient. Europium-147 that decays by electron capture or β + -particle emission is a proton-rich nuclide and the γ-ray emission probabilities evaluated by Mateosian and Peker have large uncertainties. They referred to only one report concerning with γ-ray emission probabilities. Our final purpose is to determine the precise γ-ray emission probabilities of 147 Eu from disintegration rates and γ-ray intensities by using a 4πβ-γ coincidence apparatus. Impurity nuclides affect largely to the determination of disintegration rate; therefore, a highly pure 147 Eu source is required. This short note will describe the most proper energy for 147 Eu production through 147 Sm(p, n) reaction. (author)

  5. 40 CFR 61.183 - Emission monitoring.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Emission monitoring. 61.183 Section 61... Emissions From Arsenic Trioxide and Metallic Arsenic Production Facilities § 61.183 Emission monitoring. (a..., calibrate, maintain, and operate a continuous monitoring system for the measurement of the opacity of each...

  6. Very Strong TeV Emission as $\\gamma$-Ray Burst Afterglows

    CERN Document Server

    Totani, T

    1998-01-01

    Gamma-ray bursts (GRBs) and following afterglows are considered to be produced by dissipation of kinetic energy of a relativistic fireball and radiation process is widely believed as synchrotron radiation or inverse Compton scattering of electrons. We argue that the transfer of kinetic energy of ejecta into electrons may be inefficient process and hence the total energy released by a GRB event is much larger than that emitted in soft gamma-rays, by a factor of \\sim (m_p/m_e). We show that, in this case, very strong emission of TeV gamma-rays is possible due to synchrotron radiation of protons accelerated up to \\sim 10^{21} eV, which are trapped in the magnetic field of afterglow shock and radiate their energy on an observational time scale of \\sim day. This suggests a possibility that GRBs are most energetic in TeV range and such TeV gamma-rays may be detectable from GRBs even at cosmological distances, i.e., z gives a quantitative explanation for the famous long-duration GeV photons detected from GRB940217. ...

  7. Prompt dipole gamma-ray emission in fusionlike heavy-ion reactions

    CERN Document Server

    Pierroutsakou, D; Di Pietro, M; Mordente, R; Ordine, A; Romoli, M; De Rosa, A; Inglima, G; La Commara, M; Martin, B; Roca, V; Sandoli, M; Trotta, M; Vardaci, E; Ming, R; Rizzo, F; Soramel, F; Stroe, L

    2003-01-01

    The sup 3 sup 2 S+ sup 1 sup 0 sup 0 Mo and sup 3 sup 6 S+ sup 9 sup 6 Mo fusionlike reactions were studied at incident energy of E sub l sub a sub b =298 MeV and 320 MeV, respectively, with the aim of probing the influence of the entrance channel charge asymmetry on the dipole gamma-ray emission. The excitation energy and spin distribution of the compound nucleus created in these reactions were identical, the only difference being associated with the unequal charge asymmetry of the two entrance channels. High-energy gamma-rays were detected in an array of 9 seven-pack BaF sub 2 clusters. Coincidence with fusionlike residues detected in four PPAC ensured the selection of central reaction events. By studying the differential gamma-ray multiplicity associated with the two reactions it was shown that the dipole strength excited in the compound nucleus increases with the entrance channel charge asymmetry. From the linearized spectra, the increase of the GDR gamma-ray intensity was found to be propor to 25% for th...

  8. 40 CFR 61.163 - Emission monitoring.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Emission monitoring. 61.163 Section 61... Emissions From Glass Manufacturing Plants § 61.163 Emission monitoring. (a) An owner or operator of a glass..., calibrate, maintain, and operate a continuous monitoring system for the measurement of the opacity of...

  9. The influence of gamma irradiation on natural dyeing properties of cotton and flax fabrics

    Science.gov (United States)

    Chirila, Laura; Popescu, Alina; Cutrubinis, Mihalis; Stanculescu, Ioana; Moise, Valentin Ioan

    2018-04-01

    Fabrics made of 100% cotton and 100% flax respectively were exposed at ambient temperature to gamma radiation doses, from 5 to 40 kGy, using a Co-60 research irradiator. After the irradiation treatment the fabrics were subjected to dyeing process with Itodye Nat Pomegranate commercial natural dye. The influence of gamma irradiation treatment on the physical-mechanical properties, dyeing and surface morphology of natural fibres were investigated. Gamma ray treatment of 40 kGy was the most effective in the case of fabrics made from 100% cotton, enhancing the colour strength as evidenced by K/S value. The results obtained from the mechanical properties of fabrics made of 100% flax indicated that the dose of 40 kGy leads to a decrease of tensile strength up of to 41.5%. Infrared spectroscopy was used to monitor chemical and structural changes in cellulosic fibres induced during processing. Crystallinity indices calculated from various bands ratio showed insignificant variations for cotton and small variations in the case of flax. The surface morphology of irradiated cotton fabrics did not show significant changes even at the highest dose of 40 kGy, while the low doses applied on flax fabrics led to an appearance of small changes of surface morphology. The gamma irradiation increased the uptake of natural dyes on natural cellulosic fibres.

  10. On the regularities of gamma-ray initiated emission of really-secondary electrons

    International Nuclear Information System (INIS)

    Grudskij, M.Ya.; Roldugin, N.N.; Smirnov, V.V.

    1982-01-01

    Emission regularities of the really-secondary electrons from metals are discussed on the basis of experimental data on electron emission characteristics under gamma radiation of incident quanta produced for a wide energy range (Esub(γ)=0.03+-2 MeV) and atomic numbers of target materials (Z=13+-79). Comparison with published experimental and calculated data is performed. It is shown that yield of the really-secondary electrons into vacuum from the target surface bombarded with a normally incident collimated beam of gamma radiation calculating on energy unit absorbed in the yield zone of the really-secondary electrons is determined only with the target material emittivity and can be calculated if spatial-energy distributions and the number of secondary fast electrons emitted out of the target are known

  11. Effects of gamma-rays on an indigenous Bacillus isolate

    International Nuclear Information System (INIS)

    Jong Bor Chyan; Liew Pauline Woan Ying; Ahmad Zainuri Mohd Dzomir; Siti Khadijah Abu Hadin; Nabilahuda Mohd Tumirin

    2010-01-01

    A preliminary study was carried out with the aim to obtain strong cellulolytic bacteria by ionizing radiation using a 60 Co source. An indigenous cellulolytic Bacillus sp. NMBCC 10023 originally isolated from soil origin was used in the study. The harvested bacterial pellets from overnight growth cultures were exposed to gamma-irradiation with doses ranging from 1 kGy to 40 kGy. The numbers of surviving bacteria on agar plate decreased as the gamma irradiation dose increased. No isolates were recovered after exposure to doses greater than 10 kGy. Based on the cell count using plate count method, the 90 % lethal dose (LD90) of gamma radiation of Bacillus sp. NMBCC 10023 was between 2-4 kGy. (author)

  12. Broad Line Radio Galaxies Observed with Fermi-LAT: The Origin of the GeV Gamma-Ray Emission

    Energy Technology Data Exchange (ETDEWEB)

    Kataoka, J.; /Waseda U., RISE; Stawarz, L.; /JAXA, Sagamihara /Jagiellonian U., Astron. Observ.; Takahashi, Y.; /Waseda U., RISE; Cheung, C.C.; /Natl. Acad. Sci. /Naval Research Lab, Wash., D.C.; Hayashida, M.; /SLAC /Stanford U., HEPL /KIPAC, Menlo Park; Grandi, P.; /Bologna Observ.; Burnett, T.H.; /Washington U., Seattle; Celotti, A.; /SISSA, Trieste; Fegan, S.J.; Fortin, P.; /Ecole Polytechnique; Maeda, K.; Nakamori, T.; /Waseda U., RISE; Taylor, G.B.; /New Mexico U.; Tosti, G.; /INFN, Perugia /Perugia U.; Digel, S.W.; /SLAC /Stanford U., HEPL /KIPAC, Menlo Park; McConville, W.; /NASA, Goddard /Maryland U.; Finke, J.; /Naval Research Lab, Wash., D.C.; D' Ammando, F.; /IASF, Palermo /INAF, Rome

    2012-06-07

    We report on a detailed investigation of the {gamma}-ray emission from 18 broad line radio galaxies (BLRGs) based on two years of Fermi Large Area Telescope (LAT) data. We confirm the previously reported detections of 3C 120 and 3C 111 in the GeV photon energy range; a detailed look at the temporal characteristics of the observed {gamma}-ray emission reveals in addition possible flux variability in both sources. No statistically significant {gamma}-ray detection of the other BLRGs was however found in the considered dataset. Though the sample size studied is small, what appears to differentiate 3C 111 and 3C 120 from the BLRGs not yet detected in {gamma}-rays is the particularly strong nuclear radio flux. This finding, together with the indications of the {gamma}-ray flux variability and a number of other arguments presented, indicate that the GeV emission of BLRGs is most likely dominated by the beamed radiation of relativistic jets observed at intermediate viewing angles. In this paper we also analyzed a comparison sample of high accretion-rate Seyfert 1 galaxies, which can be considered radio-quiet counterparts of BLRGs, and found none were detected in {gamma}-rays. A simple phenomenological hybrid model applied for the broad-band emission of the discussed radio-loud and radio-quiet type 1 active galaxies suggests that the relative contribution of the nuclear jets to the accreting matter is {ge} 1% on average for BLRGs, while {le} 0.1% for Seyfert 1 galaxies.

  13. 40 CFR 1033.715 - Banking emission credits.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Banking emission credits. 1033.715... CONTROLS CONTROL OF EMISSIONS FROM LOCOMOTIVES Averaging, Banking, and Trading for Certification § 1033.715 Banking emission credits. (a) Banking is the retention of emission credits by the manufacturer...

  14. Model-independent measurement of the CKM angle $\\gamma$ using $B^0 \\to D K^{\\ast 0}$ decays with $D \\to K_{S}^{0} \\pi^{+} \\pi^{-}$ and $K_{S}^{0} K^{+} K^{-}$

    CERN Document Server

    Aaij, Roel; Adeva, Bernardo; Adinolfi, Marco; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Andreassi, Guido; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; d'Argent, Philippe; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baker, Sophie; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Bel, Lennaert; Bellee, Violaine; Belloli, Nicoletta; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Betti, Federico; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bifani, Simone; Billoir, Pierre; Bird, Thomas; Birnkraut, Alex; Bizzeti, Andrea; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borgheresi, Alessio; Borghi, Silvia; Borisyak, Maxim; Borsato, Martino; Boubdir, Meriem; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Braun, Svende; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Buchanan, Emma; Burr, Christopher; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cavallero, Giovanni; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chatzikonstantinidis, Georgios; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chobanova, Veronika; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dall'Occo, Elena; Dalseno, Jeremy; David, Pieter; Davis, Adam; De Aguiar Francisco, Oscar; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Demmer, Moritz; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Dijkstra, Hans; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dovbnya, Anatoliy; Dreimanis, Karlis; Dufour, Laurent; Dujany, Giulio; Dungs, Kevin; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farley, Nathanael; Farry, Stephen; Fay, Robert; Fazzini, Davide; Ferguson, Dianne; Fernandez Albor, Victor; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fleuret, Frederic; Fohl, Klaus; Fontana, Marianna; Fontanelli, Flavio; Forshaw, Dean Charles; Forty, Roger; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garra Tico, Jordi; Garrido, Lluis; Garsed, Philip John; Gascon, David; Gaspar, Clara; Gavardi, Laura; Gazzoni, Giulio; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianì, Sebastiana; Gibson, Valerie; Girard, Olivier Göran; Giubega, Lavinia-Helena; Gligorov, V.V.; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadavizadeh, Thomas; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heister, Arno; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hongming, Li; Hulsbergen, Wouter; Humair, Thibaud; Hushchyn, Mikhail; Hussain, Nazim; Hutchcroft, David; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kecke, Matthieu; Kelsey, Matthew; Kenyon, Ian; Kenzie, Matthew; Ketel, Tjeerd; Khairullin, Egor; Khanji, Basem; Khurewathanakul, Chitsanu; Kirn, Thomas; Klaver, Suzanne; Klimaszewski, Konrad; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Kozeiha, Mohamad; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krokovny, Pavel; Kruse, Florian; Krzemien, Wojciech; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kuonen, Axel Kevin; Kurek, Krzysztof; Kvaratskheliya, Tengiz; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Lemos Cid, Edgar; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Liu, Xuesong; Loh, David; Longstaff, Iain; Lopes, Jose; Lucchesi, Donatella; Lucio Martinez, Miriam; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Lusardi, Nicola; Lusiani, Alberto; Lyu, Xiao-Rui; Machefert, Frederic; Maciuc, Florin; Maev, Oleg; Maguire, Kevin; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Manning, Peter Michael; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Marks, Jörg; Martellotti, Giuseppe; Martin, Morgan; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massacrier, Laure Marie; Massafferri, André; Matev, Rosen; Mathad, Abhijit; Mathe, Zoltan; Matteuzzi, Clara; Mauri, Andrea; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; Meadows, Brian; Meier, Frank; Meissner, Marco; Melnychuk, Dmytro; Merk, Marcel; Merli, Andrea; Michielin, Emanuele; Milanes, Diego Alejandro; Minard, Marie-Noelle; Mitzel, Dominik Stefan; Molina Rodriguez, Josue; Monroy, Ignacio Alberto; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Dominik; Müller, Janine; Müller, Katharina; Müller, Vanessa; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nandi, Anita; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen-Mau, Chung; Niess, Valentin; Nieswand, Simon; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Osorio Rodrigues, Bruno; Otalora Goicochea, Juan Martin; Otto, Adam; Owen, Patrick; Oyanguren, Maria Aranzazu; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Pappenheimer, Cheryl; Parker, William; Parkes, Christopher; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Pescatore, Luca; Petridis, Konstantinos; Petrolini, Alessandro; Petruzzo, Marco; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pikies, Malgorzata; Pinci, Davide; Pistone, Alessandro; Piucci, Alessio; Playfer, Stephen; Plo Casasus, Maximo; Poikela, Tuomas; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Quagliani, Renato; Rachwal, Bartolomiej; Rademacker, Jonas; Rama, Matteo; Ramos Pernas, Miguel; Rangel, Murilo; Raniuk, Iurii; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; dos Reis, Alberto; Renaudin, Victor; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Lopez, Jairo Alexis; Rodriguez Perez, Pablo; Rogozhnikov, Alexey; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Ronayne, John William; Rotondo, Marcello; Ruf, Thomas; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santimaria, Marco; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schael, Stefan; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmelzer, Timon; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schubiger, Maxime; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sergi, Antonino; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Siddi, Benedetto Gianluca; Silva Coutinho, Rafael; Silva de Oliveira, Luiz Gustavo; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skwarnicki, Tomasz; Smith, Eluned; Smith, Iwan Thomas; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Stefkova, Slavomira; Steinkamp, Olaf; Stenyakin, Oleg; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szumlak, Tomasz; T'Jampens, Stephane; Tayduganov, Andrey; Tekampe, Tobias; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Tournefier, Edwige; Tourneur, Stephane; Trabelsi, Karim; Traill, Murdo; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valat, Sebastien; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; van Veghel, Maarten; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Volkov, Vladimir; Vollhardt, Achim; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Weiden, Andreas; Whitehead, Mark; Wicht, Jean; Wilkinson, Guy; Wilkinson, Michael; Williams, Mark Richard James; Williams, Matthew; Williams, Mike; Williams, Timothy; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wraight, Kenneth; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xu, Zhirui; Yang, Zhenwei; Yin, Hang; Yu, Jiesheng; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Yanxi; Zhelezov, Alexey; Zheng, Yangheng; Zhokhov, Anatoly; Zhong, Liang; Zhukov, Valery; Zucchelli, Stefano

    2016-06-21

    A binned Dalitz plot analysis of the decays $B^0 \\to D K^{\\ast 0}$, with $D \\to K_{S}^{0} \\pi^{+} \\pi^{-}$ and $D \\to K_{S}^{0} K^{+} K^{-}$, is performed to measure the observables $x_\\pm$ and $y_\\pm$, which are related to the CKM angle $\\gamma$ and the hadronic parameters of the decays. The $D$ decay strong phase variation over the Dalitz plot is taken from measurements performed at the CLEO-c experiment, making the analysis independent of the $D$ decay model. With a sample of proton-proton collision data, corresponding to an integrated luminosity of $3.0\\,\\rm{fb}^{-1}$, collected by the LHCb experiment, the values of the $CP$ violation parameters are found to be $x_+ = 0.05 \\pm 0.35 \\pm 0.02$, $x_-=-0.31\\pm 0.20 \\pm 0.04$, $y_+=-0.81\\pm 0.28\\pm 0.06$ and $y_-=0.31\\pm 0.21 \\pm 0.05$, where the first uncertainties are statistical and the second systematic. These observables correspond to values $\\gamma$ = $(71 \\pm 20)^\\circ$, $r_{B^0} = 0.56\\pm 0.17$ and $\\delta_{B^0} = (204\\,^{+21}_{-20})^\\circ$. The parame...

  15. Use of LabSOCS for determination of specific concentrations of 40K, 238U and 232Th in fertilizer samples

    International Nuclear Information System (INIS)

    Garcez, Ricardo Washington Dutra; Lopes, Jose Marques; Silva, Ademir Xavier da; Domingues, Alessandro Mariano; Lima, Marco Frota

    2015-01-01

    Use of fertilizer is an established practice worldwide to promote agricultural productivity increased without increasing the planted area, resulting in native forests protection and increase of the food availability. Some kinds of fertilizer have in their chemical composition some radionuclides due the origin of its feedstock, such as 238 U, the 232 Th, and their descendants, beyond 40 K. Knowledge of the radioactivity levels in the environment is great importance to know the gamma radiation dose that the human being is exposed. For identification and quantitation of radionuclides, it was used gamma spectrometry where HPGe detector was used to obtain the spectra, and LabSOCS software for calculating the detection efficiency for each energy. The values of 232 Th specific concentrations ranged from 4.1 to 368.1 Bq.Kg -1 , the values of 238 U specific concentrations ranged from 16.0 to 647.7 Bq.Kg -1 and 40 K specific concentrations ranged from 19.1 to 12713 Bq.Kg -1 . Concentrations of values are consistent with those found in literature. (author)

  16. Monte Carlo simulations of prompt-gamma emission during carbon ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Le Foulher, F.; Bajard, M.; Chevallier, M.; Dauvergne, D.; Henriquet, P.; Ray, C.; Testa, E.; Testa, M. [Universite de Lyon 1, F-69003 Lyon (France); IN2P3/CNRS, UMR 5822, Institut de Physique Nucleaire de Lyon, F-69622 Villeurbanne (France); Freud, N.; Letang, J. M. [Laboratoire de Controles Non Destructifs Par Rayonnements Ionisants, INSA-Lyon, F-69621 Villeurbanne cedex (France); Karkar, S. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Plescak, R.; Schardt, D. [Gesellschaft fur Schwerionenforschung (GSI), D-64291 Darmstadt (Germany)

    2009-07-01

    Monte Carlo simulations based on the Geant4 tool-kit (version 9.1) were performed to study the emission of secondary prompt gamma-rays produced by nuclear reactions during carbon ion-beam therapy. These simulations were performed along with an experimental program and instrumentation developments which aim at designing a prompt gamma-ray device for real-time control of hadron therapy. The objective of the present study is twofold: first, to present the features of the prompt gamma radiation in the case of carbon ion irradiation; secondly, to simulate the experimental setup and to compare measured and simulated counting rates corresponding to various experiments. For each experiment, we found that simulations overestimate prompt gamma-ray detection yields by a factor of 12. Uncertainties in fragmentation cross sections and binary cascade model cannot explain such discrepancies. The so-called 'photon evaporation' model is therefore questionable and its modification is currently in progress. (authors)

  17. Accumulation and translocation peculiarities of "1"3"7Cs and "4"0K in the soil – plant system

    International Nuclear Information System (INIS)

    Marčiulionienė, Danutė; Lukšienė, Benedikta; Jefanova, Olga

    2015-01-01

    Long-term investigations (1996–2008) were conducted into the "1"3"7Cs and "4"0K in the soil of forests, swamps and meadows in different regions of Lithuania, as well as in the plants growing in these media. The "1"3"7Cs and "4"0K activity concentrations, the "1"3"7Cs/"4"0K activity concentration ratio and accumulation, and translocation in the system, i.e. from the soil to plant roots to above-ground plant part of these radionuclides, were evaluated after gamma-spectrometric measurements using a high purity germanium (HPGe) detector. Based on the obtained data, it can be asserted that in the tested plant species, the "1"3"7Cs and "4"0K accumulation, the transfer from soil to roots and translocation within the plants depend on the plant species and environmental ecological conditions. The "1"3"7Cs/"4"0K activity concentration ratios in the same plant species in different regions of Lithuania are different and this ratio depends on the biotope (forest, swamp or meadow) in which the plant grows and on the location of the growing region. Based on the determined trends of statistically reliable inverse dependence between the activity concentrations in both soil and plants, it can be stated that the exchange of "1"3"7Cs and "4"0K in plants and soil is different. Different accumulations and translocations of investigated radionuclides in the same plant species indicate diverse biological metabolism of "1"3"7Cs and its chemical analogue "4"0K in plants. A competitive relationship exists between "1"3"7Cs and "4"0K in plants as well as in the soil. - Highlights: • Investigations of "1"3"7Cs and "4"0K were performed in different ecological conditions. • The data indicate a diverse biological metabolism of "1"3"7Cs and "4"0K in plant species. • A pronounced association between "1"3"7Cs and "4"0K in soil and plants is not statistically significant. • A competitive relationship exists between "1"3"7Cs and "4"0K in plants as well as in the soil. • The ratio of "1

  18. 40 CFR 60.31d - Emissions guidelines.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Emissions guidelines. 60.31d Section 60...) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emissions Guidelines and Compliance Times for Sulfuric Acid Production Units § 60.31d Emissions guidelines. Sulfuric acid production units. The emission...

  19. Search for TeV gamma ray emission from the Andromeda galaxy

    Science.gov (United States)

    Aharonian, F. A.; Akhperjanian, A. G.; Beilicke, M.; Bernlöhr, K.; Bojahr, H.; Bolz, O.; Börst, H.; Coarasa, T.; Contreras, J. L.; Cortina, J.; Denninghoff, S.; Fonseca, V.; Girma, M.; Götting, N.; Heinzelmann, G.; Hermann, G.; Heusler, A.; Hofmann, W.; Horns, D.; Jung, I.; Kankanyan, R.; Kestel, M.; Kettler, J.; Kohnle, A.; Konopelko, A.; Kornmeyer, H.; Kranich, D.; Krawczynski, H.; Lampeitl, H.; Lopez, M.; Lorenz, E.; Lucarelli, F.; Mang, O.; Meyer, H.; Mirzoyan, R.; Moralejo, A.; Ona, E.; Panter, M.; Plyasheshnikov, A.; Pühlhofer, G.; Rauterberg, G.; Reyes, R.; Rhode, W.; Ripken, J.; Röhring, A.; Rowell, G. P.; Sahakian, V.; Samorski, M.; Schilling, M.; Siems, M.; Sobzynska, D.; Stamm, W.; Tluczykont, M.; Völk, H. J.; Wiedner, C. A.; Wittek, W.

    2003-03-01

    Using the HEGRA system of imaging atmospheric Cherenkov telescopes, the Andromeda galaxy (M 31) was surveyed for TeV gamma ray emission. Given the large field of view of the HEGRA telescopes, three pointings were sufficient to cover all of M 31, including also M 32 and NGC 205. No indications for point sources of TeV gamma rays were found. Upper limits are given at a level of a few percent of the Crab flux. A specific search for monoenergetic gamma-ray lines from annihilation of supersymmetric dark matter particles accumulating near the center of M 31 resulted in flux limits in the 10-13 cm-2 s-1 range, well above the predicted MSSM flux levels except for models with pronounced dark-matter spikes or strongly enhanced annihilation rates.

  20. Solar Coronal Events with Extended Hard X-ray and Gamma-ray Emission

    Science.gov (United States)

    Hudson, H. S.

    2017-12-01

    A characteristic pattern of solar hard X-ray emission, first identified in SOL1969-03-31 by Frost & Dennis (1971) now has been linked to prolonged high-energy gamma-ray emission detected by the Fermi/LAT experiment, for example in SOL2014-09-01. The distinctive features of these events include flat hard X-ray spectra extending well above 100 keV, a characteristic pattern of time development, low-frequency gyrosynchrotron peaks, CME association, and gamma-rays identifiable with pion decay originating in GeV ions. The identification of these events with otherwise known solar structures nevertheless remains elusive, in spite of the wealth of imagery available from AIA. The quandary is that these events have a clear association with CMEs in the high corona, and yet the gamma-ray production implicates the photosphere itself. The vanishingly small loss cone in the nominal acceleration region makes this extremely difficult. I propose direct inward advection of a part of the SEP particle population, as created on closed field structures, as a possible resolution of this puzzle, and note that this requires retracting magnetic structures on long time scales following the flare itself.

  1. Measurement of 238U, 232Th and 40K concentrations in different regions of Colombia

    Science.gov (United States)

    Rodríguez, W.; Lizarazo, C.; Cortés, M. L.; Rodríguez, S. A.; Mendoza, E. F.; Cristancho, F.

    2012-02-01

    Taking into account the wide variety of geological structures in Colombia, we took a collection of samples both from sand beaches and high mountains systems and determined their concentration of 238U, 232Th and 40K using a high resolution gamma spectrometry system. The results show a variation of these concentrations for the different samples that we associate with the soil type and the environmental conditions of the chosen regions. We also compare our results with other studies carried out in regions with similar geological conditions.

  2. X-ray emission from open star clusters with Spectrum-Rontgen-Gamma

    DEFF Research Database (Denmark)

    Singh, K.P.; Ojha, D.K.; Schnopper, H.W.

    1998-01-01

    The study of X-ray emission from co-evolving populations of stars in open dusters is extremely important for understanding the dynamo activity among the stars. With this objective, we propose to observe a number of open clusters in the X-ray and UV bands using SPECTRUM-Rontgen-Gamma. The high...... throughput of SPECTRUM-Rontgen-Gamma will help detect main sequence stars like Sun in middle-aged and old clusters. We will study the relationships between various parameters - age, rotation, abundance, UBV colors, X-ray luminosity, coronal temperature etc. X-ray spectra of younger and brighter populations...

  3. Determination of K-40 in croquettes

    International Nuclear Information System (INIS)

    Escalona L, M. I.; Campillo R, G. E.; Vega C, H. R.; Garcia S, E.

    2017-10-01

    The health of the pets depends on several factors; one of the most important is the quality of their diet. The dog (Canis lupus familiaris) is a carnivorous mammal of the family of canines that is part of the most accepted pets. For the feeding of these pets is common to use industrial foods such as croquettes that offer many advantages, however they also contribute to the intake of radioisotopes that can affect their health. Potassium is an essential element for health, naturally there are 3 isotopes: K-39, K-40 and K-41. The K-40 is radioactive with 1,248 x 10 9 years of half-life that when decaying emits beta particles and photons of 1.42 MeV. In this work, potassium 40 activity was determined in croquette brands: Dog Chow, Canine Power and Exceed; KCl was used as a standard and dehydrated pea was used as control. The croquettes and peas were ground and weighed 160 grams of each sample, of KCl and pea, which were placed in Marinelli containers that were measured with a spectrometric system for γ rays and with a Nal(Tl) scintillator of 7.62 cm in diameter and 7.62 cm in height. It was found that the average activity of K-40 in all the measured brands is 5.0 ± 0.3 Bq per croquettes gram. (Author)

  4. Potential radionuclide emissions from stacks on the Hanford Site, Part 2: Dose assessment methodology using portable low-resolution gamma spectroscoy

    International Nuclear Information System (INIS)

    Barnett, J.M.

    1994-07-01

    In September 1992, the Westinghouse Hanford Company began developing an in situ measurement method to assess gamma radiation emanating from high-efficiency particulate air filters using portable low-resolution gamma spectroscopy. The purpose of the new method was to assess radioactive exhaust stack air emissions from empirical data rather than from theoretical models and to determine the potential unabated dose to an offsite theoretical maximally exposed individual. In accordance with Title 40, Code of Federal Regulations, Part 61, Subpart H, ''National Emission Standards for Hazardous Air Pollutants'', stacks that have the potential to emit ≥ 0.1 mrem per year to the maximally exposed individual are considered ''major'' and must meet the continuous monitoring requirements. After the method was tested and verified, the US Environmental Protection Agency, Region 10, approved its use in June 1993. Of the 125 stacks operated by the Westinghouse Hanford Company, 22 were targeted for evaluation by this method; and 15 were assessed. The most significant,result from this study was the redesignation. of the T Plant main stack. The stack was assessed as being ''minor'', and it now only requires periodic confirmatory measurements and meets federally imposed sampling requirements

  5. Diffusion in the Muscovite 40K Decay System (Invited)

    Science.gov (United States)

    Harrison, T. M.

    2010-12-01

    The considerable potential of muscovite for thermochronological applications is beginning to be fully exploited following the belated publication of Ar kinetic data. Muscovite’s high potassium content, low solubility for excess 40Ar*, and ubiquitous presence in regionally metamorphosed terranes make it an important phase for 40Ar/39Ar thermochronometry, particularly in light of recognition that both age spectra and vacuum-step-heating-derived 39Ar Arrhenius plots reflect Ar release via the same volume diffusion mechanism. Thus instead of assuming a nominal closure temperature to estimate a single T-t datum, continuous and accurate thermal histories can be inferred in a similar fashion to that well-documented for K-feldspar using the multi-diffusion domain (MDD) model. The Arrhenius parameters for Ar diffusion in muscovite (E=64 kcal/mol, Do=4 cm2/s) correspond to an effective intragrain closure temperature range of ~500 to 300oC for ca. 100 μm grains cooling at ~10oC/Ma at 5 kbar. However, even greater exploitation of the 40K decay system remains possible as only one of every ten 40K atoms decay to 40Ar. The other 90% decay to 40Ca giving the 40K-40Ca branch, in principle, greater sensitivity for dating high K/Ca minerals such as muscovite. The advent of the ‘double-plus’ SIMS 40K++-40Ca++ dating method, which permits analysis of Ca isotopes at an MRP of ~4k rather than the ~25k required for full separation of 40K+ from 40Ca+, opens up the prospect of directly revealing 40K-40Ca closure profiles in muscovite (as opposed to their indirect inference from inversion of 40Ar/39Ar data through the MDD model) at a gain of enhanced precision and accuracy in thermal history reconstruction. We have used SIMS to observe K-Ca age variations in natural muscovites pressed into In. Translating this data into thermal history information, however, requires knowledge of the Arrhenius parameters for Ca tracer diffusion in muscovite. We are undertaking hydrothermal piston

  6. 40 CFR 76.10 - Alternative emission limitations.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Alternative emission limitations. 76.10 Section 76.10 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.10 Alternative emission limitations. (a...

  7. Gamma-burst emission from neutron-star accretion

    Science.gov (United States)

    Colgate, S. A.; Petschek, A. G.; Sarracino, R.

    1983-01-01

    A model for emission of the hard photons of gamma bursts is presented. The model assumes accretion at nearly the Eddington limited rate onto a neutron star without a magnetic field. Initially soft photons are heated as they are compressed between the accreting matter and the star. A large electric field due to relatively small charge separation is required to drag electrons into the star with the nuclei against the flux of photons leaking out through the accreting matter. The photon number is not increased substantially by Bremsstrahlung or any other process. It is suggested that instability in an accretion disc might provide the infalling matter required.

  8. The Prompt and High Energy Emission of Gamma Ray Bursts

    International Nuclear Information System (INIS)

    Meszaros, P.

    2009-01-01

    I discuss some recent developments concerning the prompt emission of gamma-ray bursts, in particular the jet properties and radiation mechanisms, as exemplified by the naked-eye burst GRB 080319b, and the prompt X-ray emission of XRB080109/SN2008d, where the progenitor has, for the first time, been shown to contribute to the prompt emission. I discuss then some recent theoretical calculations of the GeV/TeV spectrum of GRB in the context of both leptonic SSC models and hadronic models. The recent observations by the Fermi satellite of GRB 080916C are then reviewed, and their implications for such models are discussed, together with its interesting determination of a bulk Lorentz factor, and the highest lower limit on the quantum gravity energy scale so far.

  9. Search for gamma ray emission above 20 MeV from the Crab nebula and the NP 0532 pulsar

    International Nuclear Information System (INIS)

    Leray, J.-P.

    1976-08-01

    The search for gamma-ray emission above 20 MeV from the Crab Nebula and Pulsar NP 0532 was undertaken. A critical analysis of the detector is presented together with a study of the background. The observed flux from the sources are compared with a theoretical model for the gamma-ray emission bases on the synchrotron process in the Crab Nebula and Pulsar NP 0532 [fr

  10. The Study of the Cosmic Gamma-Emission Nonstationary Fluxes Characteristics by the AVS-F Apparatus Data

    Science.gov (United States)

    Kotov, Yu. D.; Arkhangelskaja, I. V.; Arkhangelsky, A. I.; Kuznetsov, S. N.; Glyanenko, A. S.; Kalmykov, P. A.; Amandzholova, D. B.; Samoylenko, V. T.; Yurov, V. N.; Pavlov, A. V.; Chervyakova, O. I.; Afonina, I. V.

    The AVS-F apparatus (Russian abbreviation for Amplitude-Time Spectrometry of the Sun) is intended for the solar flares' hard X-ray and gamma-ray emission characteristic studies and for the search and detection of the gamma-ray bursts (GRB). At present over 1,100 events with duration more than 2 s without any coordinate relations to Earth Radiation Belts and South Atlantic Anomaly were separated on the results of preliminary analysis of AVS-F experiment database.About 68 % of the identified events were associated with quasistationary equatorial precipitations-15-30 % count rate increases in the low-energy gamma-band of the AVS-F apparatus over its average value obtained by approximation of these parts with polynomials discovered on some equatorial segments in the ranges of geographic latitude of 25∘ up to +30∘. Several short events with duration of 1-16 ms associated with terrestrial gamma-ray flashes were registered during the experiment. These events were detected above the powerful thunderstorm formations.Solar flares with classes stronger than M1.0 according to the GOES classification were about 7 % of the detected events. Solar flares' hard X-rays and γ-emission were mainly observed during the rise or maximum phases of the emission in the soft X-rays band according to the detectors on board the GOES series satellites data and duration of their registration is less than of the soft X-ray bands. According to the preliminary data analysis gamma-emission with energy over 10 MeV was registered during 12 % of the observed flares. The emission in the energy band E ¿ 100 keV was registered during over 60 faint solar flares (of B and C classes according to the GOES and from several ones γ-quanta with energy up to several tens of MeV were observed.Several spectral line complexes were observed in the spectra of some solar flares stronger than M1.0 in the low-energy gamma-range. Registered spectral features were corresponded to α α-lines, annihilation line

  11. EGRET upper limits to the high-energy gamma-ray emission from the millisecond pulsars in nearby globular clusters

    Science.gov (United States)

    Michelson, P. F.; Bertsch, D. L.; Brazier, K.; Chiang, J.; Dingus, B. L.; Fichtel, C. E.; Fierro, J.; Hartman, R. C.; Hunter, S. D.; Kanbach, G.

    1994-01-01

    We report upper limits to the high-energy gamma-ray emission from the millisecond pulsars (MSPs) in a number of globular clusters. The observations were done as part of an all-sky survey by the energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory (CGRO) during Phase I of the CGRO mission (1991 June to 1992 November). Several theoretical models suggest that MSPs may be sources of high-energy gamma radiation emitted either as primary radiation from the pulsar magnetosphere or as secondary radiation generated by conversion into photons of a substantial part of the relativistic e(+/-) pair wind expected to flow from the pulsar. To date, no high-energy emission has been detected from an individual MSP. However, a large number of MSPs are expected in globular cluster cores where the formation rate of accreting binary systems is high. Model predictions of the total number of pulsars range in the hundreds for some clusters. These expectations have been reinforced by recent discoveries of a substantial number of radio MSPs in several clusters; for example, 11 have been found in 47 Tucanae (Manchester et al.). The EGRET observations have been used to obtain upper limits for the efficiency eta of conversion of MSP spin-down power into hard gamma rays. The upper limits are also compared with the gamma-ray fluxes predicted from theoretical models of pulsar wind emission (Tavani). The EGRET limits put significant constraints on either the emission models or the number of pulsars in the globular clusters.

  12. Fermi observations of high-energy gamma-ray emission from GRB 080916C.

    Science.gov (United States)

    Abdo, A A; Ackermann, M; Arimoto, M; Asano, K; Atwood, W B; Axelsson, M; Baldini, L; Ballet, J; Band, D L; Barbiellini, G; Baring, M G; Bastieri, D; Battelino, M; Baughman, B M; Bechtol, K; Bellardi, F; Bellazzini, R; Berenji, B; Bhat, P N; Bissaldi, E; Blandford, R D; Bloom, E D; Bogaert, G; Bogart, J R; Bonamente, E; Bonnell, J; Borgland, A W; Bouvier, A; Bregeon, J; Brez, A; Briggs, M S; Brigida, M; Bruel, P; Burnett, T H; Burrows, D; Busetto, G; Caliandro, G A; Cameron, R A; Caraveo, P A; Casandjian, J M; Ceccanti, M; Cecchi, C; Celotti, A; Charles, E; Chekhtman, A; Cheung, C C; Chiang, J; Ciprini, S; Claus, R; Cohen-Tanugi, J; Cominsky, L R; Connaughton, V; Conrad, J; Costamante, L; Cutini, S; Deklotz, M; Dermer, C D; de Angelis, A; de Palma, F; Digel, S W; Dingus, B L; do Couto E Silva, E; Drell, P S; Dubois, R; Dumora, D; Edmonds, Y; Evans, P A; Fabiani, D; Farnier, C; Favuzzi, C; Finke, J; Fishman, G; Focke, W B; Frailis, M; Fukazawa, Y; Funk, S; Fusco, P; Gargano, F; Gasparrini, D; Gehrels, N; Germani, S; Giebels, B; Giglietto, N; Giommi, P; Giordano, F; Glanzman, T; Godfrey, G; Goldstein, A; Granot, J; Greiner, J; Grenier, I A; Grondin, M-H; Grove, J E; Guillemot, L; Guiriec, S; Haller, G; Hanabata, Y; Harding, A K; Hayashida, M; Hays, E; Hernando Morat, J A; Hoover, A; Hughes, R E; Jóhannesson, G; Johnson, A S; Johnson, R P; Johnson, T J; Johnson, W N; Kamae, T; Katagiri, H; Kataoka, J; Kavelaars, A; Kawai, N; Kelly, H; Kennea, J; Kerr, M; Kippen, R M; Knödlseder, J; Kocevski, D; Kocian, M L; Komin, N; Kouveliotou, C; Kuehn, F; Kuss, M; Lande, J; Landriu, D; Larsson, S; Latronico, L; Lavalley, C; Lee, B; Lee, S-H; Lemoine-Goumard, M; Lichti, G G; Longo, F; Loparco, F; Lott, B; Lovellette, M N; Lubrano, P; Madejski, G M; Makeev, A; Marangelli, B; Mazziotta, M N; McBreen, S; McEnery, J E; McGlynn, S; Meegan, C; Mészáros, P; Meurer, C; Michelson, P F; Minuti, M; Mirizzi, N; Mitthumsiri, W; Mizuno, T; Moiseev, A A; Monte, C; Monzani, M E; Moretti, E; Morselli, A; Moskalenko, I V; Murgia, S; Nakamori, T; Nelson, D; Nolan, P L; Norris, J P; Nuss, E; Ohno, M; Ohsugi, T; Okumura, A; Omodei, N; Orlando, E; Ormes, J F; Ozaki, M; Paciesas, W S; Paneque, D; Panetta, J H; Parent, D; Pelassa, V; Pepe, M; Perri, M; Pesce-Rollins, M; Petrosian, V; Pinchera, M; Piron, F; Porter, T A; Preece, R; Rainò, S; Ramirez-Ruiz, E; Rando, R; Rapposelli, E; Razzano, M; Razzaque, S; Rea, N; Reimer, A; Reimer, O; Reposeur, T; Reyes, L C; Ritz, S; Rochester, L S; Rodriguez, A Y; Roth, M; Ryde, F; Sadrozinski, H F-W; Sanchez, D; Sander, A; Saz Parkinson, P M; Scargle, J D; Schalk, T L; Segal, K N; Sgrò, C; Shimokawabe, T; Siskind, E J; Smith, D A; Smith, P D; Spandre, G; Spinelli, P; Stamatikos, M; Starck, J-L; Stecker, F W; Steinle, H; Stephens, T E; Strickman, M S; Suson, D J; Tagliaferri, G; Tajima, H; Takahashi, H; Takahashi, T; Tanaka, T; Tenze, A; Thayer, J B; Thayer, J G; Thompson, D J; Tibaldo, L; Torres, D F; Tosti, G; Tramacere, A; Turri, M; Tuvi, S; Usher, T L; van der Horst, A J; Vigiani, L; Vilchez, N; Vitale, V; von Kienlin, A; Waite, A P; Williams, D A; Wilson-Hodge, C; Winer, B L; Wood, K S; Wu, X F; Yamazaki, R; Ylinen, T; Ziegler, M

    2009-03-27

    Gamma-ray bursts (GRBs) are highly energetic explosions signaling the death of massive stars in distant galaxies. The Gamma-ray Burst Monitor and Large Area Telescope onboard the Fermi Observatory together record GRBs over a broad energy range spanning about 7 decades of gammaray energy. In September 2008, Fermi observed the exceptionally luminous GRB 080916C, with the largest apparent energy release yet measured. The high-energy gamma rays are observed to start later and persist longer than the lower energy photons. A simple spectral form fits the entire GRB spectrum, providing strong constraints on emission models. The known distance of the burst enables placing lower limits on the bulk Lorentz factor of the outflow and on the quantum gravity mass.

  13. Fermi Observations of high-energy gamma-ray emissions from GRB 080916C

    CERN Document Server

    Abdo, A A; Arimoto, M; Asano, K; Atwood, W B; Axelsson, M; Baldini, L; Ballet, J; Band, D L; Barbiellini, Guido; Baring, Matthew G; Bastieri, Denis; Battelino, M; Baughman, B M; Bechtol, K; Bellardi, F; Bellazzini, R; Berenji, B; Bhat, P N; Bissaldi, E; Blandford, R D; Bloom, Elliott D; Bogaert, G; Bogart, J R; Bonamente, E; Bonnell, J; Borgland, A W; Bouvier, A; Bregeon, J; Brez, A; Briggs, M S; Brigida, M; Bruel, P; Burnett, Thompson H; Burrows, David N; Busetto, Giovanni; Caliandro, G A; Cameron, R A; Caraveo, P A; Casandjian, J M; Ceccanti, M; Cecchi, C; Celotti, Annalisa; Charles, E; Chekhtman, A; Cheung, C.C.Teddy; Chiang, J; Ciprini, S; Claus, R; Cohen-Tanugi, Johann; Cominsky, Lynn R; Connaughton, V; Conrad, J; Costamante, L; Cutini, S; DeKlotz, M; Dermer, C D; De Angelis, Alessandro; de Palma, F; Digel, S W; Dingus, B L; do Couto e Silva, Eduardo; Drell, P S; Dubois, R; Dumora, D; Edmonds, Y; Evans, P A; Fabiani, D; Farnier, C; Favuzzi, C; Finke, Justin D; Fishman, G; Focke, W B; Frailis, M; Fukazawa, Y; Funk, S; Fusco, P; Gargano, F; Gasparrini, D; Gehrels, N; Germani, S; Giebels, B; Giglietto, N; Giommi, P; Giordano, F; Glanzman, Thomas Lynn; Godfrey, Gary L; Goldstein, A; Granot, J; Greiner, J; Grenier, I A; Grondin, M H; Grove, J.Eric; Guillemot, L; Guiriec, S; Haller, G; Hanabata, Y; Harding, Alice K; Hayashida, M; Hays, Elizabeth A; Hernando Morata, J A; Hoover, A; Hughes, R E; Johannesson, G; Johnson, A S; Johnson, R P; Johnson, T J; Johnson, W N; Kamae, Tsuneyoshi; Katagiri, H; Kataoka, J; Kavelaars, A; Kawai, N; Kelly, H; Kennea, J; Kerr, M; Kippen, R M; Knodlseder, J; Kocevski, D; Kocian, M L; Komin, N; Kouveliotou, C; Kuehn, Frederick Gabriel Ivar; Kuss, Michael; Lande, J; Landriu, D; Larsson, S; Latronico, L; Lavalley, C; Lee, B; Lee, S H; Lemoine-Goumard, M; Lichti, G G; Longo, F; Loparco, F; Lott, B; Lovellette, M N; Lubrano, Pasquale; Madejski, G M; Makeev, A; Marangelli, B; Mazziotta, M N; McBreen, Sheila; McEnery, J E; McGlynn, S; Meegan, C; Miszaros, P; Meurer, C; Michelson, P F; Minuti, M; Mirizzi, N; Mitthumsiri, W; Mizuno, T; Moiseev, A A; Monte, C; Monzani, M E; Moretti, E; Morselli, A; Moskalenko, Igor Vladimirovich; Murgia, Simona; Nakamori, T; Nelson, D; Nolan, P L; Norris, J P; Nuss, E; Ohno, M; Ohsugi, Takashi; Okumura, Akira; Omodei, N; Orlando, E; Ormes, J F; Ozaki, M; Paciesas, W S; Paneque, D; Panetta, J H; Parent, D; Pelassa, V; Pepe, M; Perri, M; Pesce-Rollins, M; Petrosian, Vahe; Pinchera, M; Piron, F; Porter, Troy A; Preece, R; Rainr, S; Ramirez-Ruiz, E; Rando, R; Rapposelli, E; Razzano, M; Razzaque, Soebur; Rea, N; Reimer, A; Reimer, O; Reposeur, Thierry; Reyes, Luis C; Ritz, S; Rochester, L S; Rodriguez, A Y; Roth, M; Ryde, F; Sadrozinski, H F W; Sanchez, D; Sander, A; Parkinson, P.M.Saz; Scargle, J D; Schalk, T L; Segal, K N; Sgro, C; Shimokawabe, T; Siskind, E J; Smith, D A; Smith, P D; Spandre, G; Spinelli, P; Stamatikos, M; Starck, Jean-Luc; Stecker, Floyd William; Steinle, H; Stephens, T E; Strickman, M S; Suson, Daniel J; Tagliaferri, G.; Tajima, Hiroyasu; Takahashi, H; Takahashi, T; Tanaka, T; Tenze, A; Thayer, J B; Thayer, J G; Thompson, D J; Tibaldo, L; Torres, Diego F; Tosti, G; Tramacere, A; Turri, M; Tuvi, S; Usher, T L; van der Horst, A J; Vigiani, L; Vilchez, N; Vitale, V; von Kienlin, A; Waite, A P; Williams, D A; Wilson-Hodge, C; Winer, B L; Wood, K S; Wu, X F; Yamazaki, R; Ylinen, T; Ziegler, M

    2009-01-01

    Gamma-ray bursts (GRBs) are highly energetic explosions signaling the death of massive stars in distant galaxies. The Gamma-ray Burst Monitor and Large Area Telescope onboard the Fermi Observatory together record GRBs over a broad energy range spanning about 7 decades of gammaray energy. In September 2008, Fermi observed the exceptionally luminous GRB 080916C, with the largest apparent energy release yet measured. The high-energy gamma rays are observed to start later and persist longer than the lower energy photons. A simple spectral form fits the entire GRB spectrum, providing strong constraints on emission models. The known distance of the burst enables placing lower limits on the bulk Lorentz factor of the outflow and on the quantum gravity mass.

  14. Spatial distribution of {gamma} emissivity and fast ions during ({sup 3}He)D ICRF heating experiments on JET

    Energy Technology Data Exchange (ETDEWEB)

    Start, D F.H. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Righi, E [Imperial Coll. of Science and Technology, London (United Kingdom); Warrick, C [UKAEA Culham Lab., Abingdon (United Kingdom)

    1994-07-01

    A model is presented that can simulate the {gamma} emissivity in the poloidal cross-section during ({sup 3}He)D ICRF heated discharges in JET plasmas, by merging information obtained from the fast ion distribution and from nuclear reactions producing the observed {gamma} emissivity (production of {gamma} photons during {sup 3}He-{sup 9}Be reactions). This technique can play an important role in the identification of plasma instabilities that affect the redistribution of the fast ions in the plasma, like the TAE modes and the ripple in the tokamak magnetic field. 9 refs., 4 figs., 1 tab.

  15. Conceptual design of the Radial Gamma Ray Spectrometers system for α particle and runaway electron measurements at ITER

    DEFF Research Database (Denmark)

    Nocente, Massimo; Tardocchi, Marco; Barnsley, Robin

    2017-01-01

    We here present the principles and main physics capabilities behind the design of the radial gamma ray spectrometers (RGRS) system for alpha particle and runaway electron measurements at ITER. The diagnostic benefits from recent advances in gamma-ray spectrometry for tokamak plasmas and combines...... the measurements sensitive to α particles at characteristic resonant energies and to possible anisotropies of their slowing down distribution function. An independent assessment of the neutron rate by gamma-ray emission is also feasible. In case of runaway electrons born in disruptions with a typical duration...... of 100ms, a time resolution of at least 10ms for runaway electron studies can be achieved depending on the scenario and down to a current of 40 kA by use of external gas injection. We find that the bremsstrahlung spectrum in the MeV range from confined runaways is sensitive to the electron velocity space...

  16. Assessment of environmental 226Ra, 232Th and 40K concentrations in the region of elevated radiation background in Segamat District, Johor, Malaysia

    International Nuclear Information System (INIS)

    Saleh, Muneer Aziz; Ramli, Ahmad Termizi; Alajerami, Yasser; Aliyu, Abubakar Sadiq

    2013-01-01

    Extensive environmental survey and measurements of gamma radioactivity in the soil samples collected from Segamat District were conducted. Two gamma detectors were used for the measurements of background radiation in the area and the results were used in the computation of the mean external radiation dose rate and mean weighted dose rate, which are 276 nGy h −1 and 1.169 mSv y −1 , respectively. A high purity germanium (HPGe) detector was used in the assessment of activity concentrations of 232 Th, 226 Ra and 40 K. The results of the gamma spectrometry range from 11 ± 1 to 1210 ± 41 Bq kg −1 for 232 Th, 12 ± 1 to 968 ± 27 Bq kg −1 for 226 Ra, and 12 ± 2 to 2450 ± 86 Bq kg −1 for 40 K. Gross alpha and gross beta activity concentrations range from 170 ± 50 to 4360 ± 170 Bq kg −1 and 70 ± 20 to 4690 ± 90 Bq kg −1 , respectively. These results were used in the plotting of digital maps (using ARCGIS 9.3) for isodose. The results are compared with values giving in UNSCEAR 2000. -- Highlights: • Assessment of the activities in region of elevated radiation in Segamat District. • The average dose rate found to be six times higher than the world average. • The activity of 232 Th is six times world average. • The activity of 226 Ra is four times and 40 K is lower than world average. • A digital map plotted for isodose

  17. INTEGRAL Upper Limits on Gamma-Ray Emission Associated with the Gravitational Wave Event GW150914

    DEFF Research Database (Denmark)

    Savchenko, V.; Ferrigno, C.; Natalucci, L.

    Using observations of the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL), we place upper limits on the gamma-ray and hard X-ray prompt emission associated with the gravitational wave event GW150914, discovered by the LIGO/Virgo Collaboration. The omnidirectional view of the INTEGRAL...... MeV energy range for typical spectral models. Our results constrain the ratio of the energy promptly released in gamma-rays in the direction of the observer to the gravitational wave energy Eγ/EGW gravitational wave...

  18. Polarized Gamma-Ray Emission from the Galactic Black Hole Cygnus X-1

    Science.gov (United States)

    Laurent, P.; Rodriquez, J.; Wilms, J.; Bel, M. Cadolle; Pottschmidt, K.; Grinberg, V.

    2011-01-01

    Because of their inherently high flux allowing the detection of clear signals, black hole X-ray binaries are interesting candidates for polarization studies, even if no polarization signals have been observed from them before. Such measurements would provide further detailed insight into these sources' emission mechanisms. We measured the polarization of the gamma-ray emission from the black hole binary system Cygnus X-I with the INTEGRAL/IBIS telescope. Spectral modeling ofthe data reveals two emission mechanisms: The 250-400 keY data are consistent with emission dominated by Compton scattering on thermal electrons and are weakly polarized. The second spectral component seen in the 400keV-2MeV band is by contrast strongly polarized, revealing that the MeV emission is probably related to the jet first detected in the radio band.

  19. The Spectrum of Isotropic Diffuse Gamma-Ray Emission Between 100 Mev and 820 Gev

    Science.gov (United States)

    Ackermann, M.; Ajello, M.; Albert, A.; Atwood, W. B.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Brandt, T. J.; Hays, E.; hide

    2014-01-01

    The gamma-ray sky can be decomposed into individually detected sources, diffuse emission attributed to the interactions of Galactic cosmic rays with gas and radiation fields, and a residual all-sky emission component commonly called the isotropic diffuse gamma-ray background (IGRB). The IGRB comprises all extragalactic emissions too faint or too diffuse to be resolved in a given survey, as well as any residual Galactic foregrounds that are approximately isotropic. The first IGRB measurement with the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope (Fermi) used 10 months of sky-survey data and considered an energy range between 200 MeV and 100 GeV. Improvements in event selection and characterization of cosmic-ray backgrounds, better understanding of the diffuse Galactic emission, and a longer data accumulation of 50 months, allow for a refinement and extension of the IGRB measurement with the LAT, now covering the energy range from 100 MeV to 820 GeV. The IGRB spectrum shows a significant high-energy cutoff feature, and can be well described over nearly four decades in energy by a power law with exponential cutoff having a spectral index of 2.32 plus or minus 0.02 and a break energy of (279 plus or minus 52) GeV using our baseline diffuse Galactic emission model. The total intensity attributed to the IGRB is (7.2 plus or minus 0.6) x 10(exp -6) cm(exp -2) s(exp -1) sr(exp -1) above 100 MeV, with an additional +15%/-30% systematic uncertainty due to the Galactic diffuse foregrounds.

  20. Determination of U, Th and K in bricks by gamma-ray spectrometry, X-ray fluorescence analysis and neutron activation analysis

    Science.gov (United States)

    Bártová, H.; Kučera, J.; Musílek, L.; Trojek, T.; Gregorová, E.

    2017-11-01

    Knowledge of the content of natural radionuclides in bricks can be important in some cases in dosimetry and application of ionizing radiation. Dosimetry of naturally occurring radionuclides in matter (NORM) in general is one of them, the other one, related to radiation protection, is radon exposure evaluation, and finally, it is needed for the thermoluminescence (TL) dating method. The internal dose rate inside bricks is caused mostly by contributions of the natural radionuclides 238U, 232Th, radionuclides of their decay chains, and 40K. The decay chain of 235U is usually much less important. The concentrations of 238U, 232Th and 40K were measured by various methods, namely by gamma-ray spectrometry, X-ray fluorescence analysis (XRF), and neutron activation analysis (NAA) which was used as a reference method. These methods were compared from the point of view of accuracy, limit of detection (LOD), amount of sample needed and sample handling, time demands, and instrument availability.

  1. 40 CFR 60.33e - Emissions guidelines.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Emissions guidelines. 60.33e Section 60...) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emission Guidelines and Compliance Times for Hospital/Medical/Infectious Waste Incinerators § 60.33e Emissions guidelines. (a) For approval, a State plan shall...

  2. SEARCH FOR PULSED {gamma}-RAY EMISSION FROM GLOBULAR CLUSTER M28

    Energy Technology Data Exchange (ETDEWEB)

    Wu, J. H. K.; Kong, A. K. H.; Huang, R. H. H.; Tam, P. H. T. [Institute of Astronomy and Department of Physics, National Tsing Hua University, Hsinchu, Taiwan (China); Hui, C. Y. [Department of Astronomy and Space Science, Chungnam National University, Daejeon (Korea, Republic of); Wu, E. M. H.; Takata, J.; Cheng, K. S., E-mail: wuhkjason@gmail.com, E-mail: cyhui@cnu.ac.kr [Department of Physics, University of Hong Kong, Pokfulam Road (Hong Kong)

    2013-03-10

    Using the data from the Large Area Telescope on board the Fermi Gamma-ray Space Telescope, we have searched for {gamma}-ray pulsations from the direction of the globular cluster M28 (NGC 6626). We report the discovery of a signal with a frequency consistent with that of the energetic millisecond pulsar (MSP) PSR B1821-24 in M28. A weighted H-test test statistic of 28.8 is attained, which corresponds to a chance probability of {approx}10{sup -5} (4.3{sigma} detection). With a phase-resolved analysis, the pulsed component is found to contribute {approx}25% of the total observed {gamma}-ray emission from the cluster. However, the unpulsed level provides a constraint for the underlying MSP population and the fundamental plane relations for the scenario of inverse Compton scattering. Follow-up timing observations in radio/X-ray are encouraged to further investigate this periodic signal candidate.

  3. 40 CFR 60.264 - Emission monitoring.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Emission monitoring. 60.264 Section 60... Facilities § 60.264 Emission monitoring. (a) The owner or operator subject to the provisions of this subpart shall install, calibrate, maintain and operate a continuous monitoring system for measurement of the...

  4. Committed dose assessment based on background outdoor gamma exposure in Chihuahua City, Mexico

    International Nuclear Information System (INIS)

    Luevano G, S.; Perez T, A.; Pinedo A, C.; Renteria V, M.; Carrillo F, J.; Montero C, M. E.

    2015-10-01

    Full text: Determining ionizing radiation in a geographic area serves to assess its effects on populations health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the committed dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, annual effective dose, and the lifetime cancer risk, 48 sampling points were randomly selected along the Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Muller counter. At the same sites, 48 soil samples were taken to obtain the activity concentrations of 226 Ra, 232 Th, 40 K and their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Outdoor gamma dose rates ranged from 56 to 193 n Gy h -1 . Results indicated that lifetime effective dose to inhabitants of Chihuahua City is in average of 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of activity concentrations in soil were 51.8, 73.1, and 1096.5 Bq kg -1 , of 226 Ra, 232 Th and 40 K, respectively. From the analysis of the spatial distribution of 232 Th, 226 Ra, and 40 K is to north, to north-center, and to south of city, respectively. In conclusion, natural background gamma dose received by inhabitants of Chihuahua City is high and mainly due to geological characteristics of the zone. (Author)

  5. Spectrometry and dosimetric evaluation of the gamma-ray emissions of 241Am

    International Nuclear Information System (INIS)

    Bradley, D.A.; Chong, C.S.

    1991-01-01

    New, detailed measurements have been made of the photon spectrum of the radionuclide 241 Am. Observations, recorded for a 95% confidence level over local background, provide affirmation of a number of lines previously considered to be of equivocal existence. A number of hitherto unreported emissions are similarly observed. Peak areas, expressed as a percentage of that for the 59.54 keV emission, have been ascribed to all lines of the detailed spectrum. This leads to an estimated increase in the value of exposure calculated from the measured fluence spectrum, relative to that from the 59.54 keV line, of (3.1 ± 0.8)%, taking into account all emissions beyond the predominating 59.54 keV gamma-ray emission. (author)

  6. 40 CFR 205.52 - Vehicle noise emission standards.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Vehicle noise emission standards. 205... ABATEMENT PROGRAMS TRANSPORTATION EQUIPMENT NOISE EMISSION CONTROLS Medium and Heavy Trucks § 205.52 Vehicle noise emission standards. (a) Low Speed Noise Emission Standard. Vehicles which are manufactured after...

  7. 40 CFR 60.84 - Emission monitoring.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Emission monitoring. 60.84 Section 60....84 Emission monitoring. (a) A continuous monitoring system for the measurement of sulfur dioxide... under § 60.13(d), shall be sulfur dioxide (SO2). Method 8 shall be used for conducting monitoring system...

  8. Cross Sections for the Reactions e+e to K+ K- pi+pi-, K+ K- pi0pi0, and K+ K- K+ K- Measured Using Initial-State Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; /INFN, Trieste /Trieste U.; Milanes, D.A.; /INFN, Trieste /Trieste U.; Palano, A.; /INFN, Trieste /Trieste U.; Pappagallo, M.; /INFN, Trieste /Trieste U. /INFN, Bari /Bari U. /Bari U. /INFN, Bari; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; /LBL, Berkeley /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Trieste /INFN, Trieste /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Ferrara /Ferrara U. /Frascati /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U., Comp. Sci. Dept. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Trieste /INFN, Trieste /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Perugia /Perugia U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Pisa /Princeton U. /INFN, Trieste /INFN, Trieste /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /INFN, Trieste /INFN, Trieste /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /INFN, Trieste /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

    2011-08-19

    We study the processes e{sup +}e{sup -} {yields} K{sup +}K{sup -}{pi}{sup +}{pi}-{gamma}, K{sup +}K{sup -}{pi}{sup 0}{pi}{sup 0}{gamma}, and K{sup +}K{sup -}K{sup +}K{sup -}{gamma}, where the photon is radiated from the initial state. About 84000, 8000, and 4200 fully reconstructed events, respectively, are selected from 454 fb{sup -1} of BABAR data. The invariant mass of the hadronic final state defines the e{sup +}e{sup -} center-of-mass energy, so that the K{sup +}K{sup -}{pi}{sup +}{pi}{sup -}{gamma} data can be compared with direct measurements of the e{sup +}e{sup -} {yields} K{sup +}K{sup -}{pi}{sup +}{pi}{sup -} reaction. No direct measurements exist for the e{sup +}e{sup -} {yields} K{sup +}K{sup -}{pi}{sup 0}{pi}{sup 0} or e{sup +}e{sup -} {yields} K{sup +}K{sup -}K{sup +}K{sup -} reactions, and we present an update of our previous result with doubled statistics. Studying the structure of these events, we find contributions from a number of intermediate states, and extract their cross sections. In particular, we perform a more detailed study of the e{sup +}e{sup -} {yields} {phi}(1020){pi}{pi}{gamma} reaction, and confirm the presence of the Y (2175) resonance in the {phi}(1020)f{sub 0}(980) and K{sup +}K{sup -} f{sub 0}(980) modes. In the charmonium region, we observe the J/{psi} in all three final states and in several intermediate states, as well as the {phi}(2S) in some modes, and measure the corresponding branching fractions.

  9. Dynamical structure of hadron emission sources

    CERN Document Server

    Zhao Xi; Zhao Shu Song

    2000-01-01

    NA22 experimental data of the triplet seagull effects show that the Doppler effects of hadron emission sources exist exactly in hadron- hadron collisions. Every source possesses the same average energy (CMS) approximately. The collective seagull effects can be also explained by the (aQ)/sup nu /K/sub nu / (aQ) distributions (generalized functions). The dynamical structure of a hadron emission source is described by the (aQ)/sup nu /K/sub nu / (aQ) distributions. The anomalous dimensions of the pionic quantum fields are gamma /sub B/(g/sub R/)=-0.045+or-0.012, which control the singularities of the production amplitude in quantum field theory. The mathematical parameter epsilon =4-D (the dimension D of space time) in the Feynman integrals can be replaced by the anomalous gamma /sub B/(g/sub R/) of the quantum fields for the regularization. (-2 gamma /sub B/(g/sub R/) to or from epsilon /2=1/ln( Lambda /sup 2//m /sup 2/) Lambda to infinity ). (26 refs).

  10. MODELING THE GAMMA-RAY EMISSION IN THE GALACTIC CENTER WITH A FADING COSMIC-RAY ACCELERATOR

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ruo-Yu; Wang, Xiang-Yu; Prosekin, Anton [Max-Planck-Institut für Kernphysik, D-69117 Heidelberg (Germany); Chang, Xiao-Chuan, E-mail: ruoyu@mpi-hd.mpg.de, E-mail: xywang@nju.edu.cn [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China)

    2016-12-20

    Recent HESS observations of the ∼200 pc scale diffuse gamma-ray emission from the central molecular zone (CMZ) suggest the presence of a PeV cosmic-ray accelerator (PeVatron) located in the inner 10 pc region of the Galactic center. Interestingly, the gamma-ray spectrum of the point-like source (HESS J1745-290) in the Galactic center shows a cutoff at ∼10 TeV, implying a cutoff around 100 TeV in the cosmic-ray proton spectrum. Here we propose that the gamma-ray emission from the inner and the outer regions may be explained self-consistently by run-away protons from a single yet fading accelerator. In this model, gamma-rays from the CMZ region are produced by protons injected in the past, while gamma-rays from the inner region are produced by protons injected more recently. We suggest that the blast wave formed in a tidal disruption event (TDE) caused by the supermassive black hole (Sgr A*) could serve as such a fading accelerator. With typical parameters of the TDE blast wave, gamma-ray spectra of both the CMZ region and HESS J1745-290 can be reproduced simultaneously. Meanwhile, we find that the cosmic-ray energy density profile in the CMZ region may also be reproduced in the fading accelerator model when appropriate combinations of the particle injection history and the diffusion coefficient of cosmic rays are adopted.

  11. Cosmology with Gamma-Ray Bursts Using k-correction

    Directory of Open Access Journals (Sweden)

    A. Kovács

    2011-01-01

    Full Text Available In the case of Gamma Ray Bursts with measured redshift, we can calculate the k-correction to get the fluence and energy that were actually produced in the comoving system of the GRB. To achieve this we have to use well-fitted parameters of GRB spectrum, available in the GCN database. The output of the calculations is the comoving isotropic energy Eiso, but this is not the endpoint: this data can be useful forestimating the ΩM parameter of the Universe and for making a GRB Hubble diagram usig Amati’s relation.

  12. 40 CFR 61.68 - Emission monitoring.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Emission monitoring. 61.68 Section 61....68 Emission monitoring. (a) A vinyl chloride monitoring system is to be used to monitor on a... monitoring system(s) used to meet the requirement in paragraph (a) of this section is to be a device which...

  13. Dynamical fission life-times deduced from gamma-ray emission observed in the fusion-fission reaction : Ne-20 on Bi-209.

    NARCIS (Netherlands)

    vanderPloeg, H; Bacelar, JCS; Buda, A; Dioszegi, [No Value; vantHof, G; vanderWoude, A

    1996-01-01

    The gamma-ray emission spectra between 4 and 20 MeV have been measured for the fusion-fission reactions Ne-20 on Bi-209 --> Np-229* at beam energies 150, 186 and 220 MeV. In addition for the latter experiment the angular dependence of the gamma-ray emission with respect to the spin axis has been

  14. Stellar and interstellar K lines - Gamma Pegasi and iota Herculis.

    Science.gov (United States)

    Hobbs, L. M.

    1973-01-01

    High-resolution scans show that the relatively strong (about 90 mA) K lines of Ca II in the early B stars gamma-Peg and iota-Her are almost entirely stellar in origin, although the latter case includes a small interstellar contribution. Such stellar lines can be of great importance in augmenting the interstellar absorption, up through the earliest of the B stars.

  15. 238 U, 232 Th and 40 K in wheat flour samples of Iraq markets

    Directory of Open Access Journals (Sweden)

    Ali Abid Abojassim

    2015-05-01

    Full Text Available Introduction. Wheat flour is a nutritious type of food that is widely consumed by various age groups in Iraq. This study investigates the presence of long-lived gamma emitters in different type of wheat flour in Iraqi market. Materials and methods. Uranium (238 U, Thorium (232 Th and Potassium (40 K specific activity in (Bq/kg were measured in (12 different types of wheat flours that are available in Iraqi markets. The gamma spectrometry method with a NaI(Tl detector has been used for radiometric measurements. Also in this study we have calculated the internal hazard index, radium equivalent and absorbed dose rate in all samples. Results and discussion. It is found that the specific activity in wheat flour samples were varied from (1.086±0.0866 Bq/kg to (12.532±2.026 Bq/kg with an average (6.6025 Bq/kg for 238 U, For 232 Th From (0.126±0.066 Bq/kg to (4.298±0.388 Bq/kg with an average (1.9465Bq/kg and for 40 K from (41.842±5.875 Bq/kg to (264.729±3.843 Bq/kg with an average (133.097 Bq/kg. Also, it is found that the radium equivalent and the internal hazard index in wheat flour samples ranged from (3.4031 Bq/kg to (35.1523 Bq/kg with an average (19.6346 Bq/kg and from (0.0091 to (0.1219 with an average (0.0708 respectively. Conclusion. This study prove that the natural radioactivity and radiation hazard indices were lower than the safe.

  16. Copper K-shell emission cross sections for laser–solid experiments

    Energy Technology Data Exchange (ETDEWEB)

    Davies, J. R.; Betti, R.; Nilson, P. M.; Solodov, A. A. [Fusion Science Center for Extreme States of Matter, Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States)

    2013-08-15

    Published measurements and models of the cross section for electrons causing K-shell emission from copper are reviewed to find a suitable expression to use when analyzing K{sub α}-emission measurements in laser–solid experiments at peak intensities above 10{sup 18} W/cm{sup 2}. Few measurements exist in the 0.1- to 10-MeV electron energy range currently of interest, leaving a number of possible suitable models that are summarized here with a number of typing errors corrected. Two different limiting forms for the cross section at relativistic energies are used, and existing measurements do not give a clear indication as to which is correct. Comparison with the limiting form of electron stopping power indicates an alternative relativistic form and also that the density-effect correction will be important in copper above 10 MeV. For data analysis relying on relative K{sub α} emission caused by electrons with energy much greater than the K-shell binding energy, the existing uncertainty in cross sections is unimportant, but it will be a source of uncertainty when using absolute values and for electron energies up to ∼6× the binding energy. K-shell emission caused by photons and protons is also briefly reviewed.

  17. LONG-TERM MONITORING OF MRK 501 FOR ITS VERY HIGH ENERGY {gamma} EMISSION AND A FLARE IN 2011 OCTOBER

    Energy Technology Data Exchange (ETDEWEB)

    Bartoli, B.; Catalanotti, S. [Dipartimento di Fisica dell' Universita di Napoli ' Federico II' , Complesso Universitario di Monte Sant' Angelo, via Cinthia, I-80126 Napoli (Italy); Bernardini, P.; Bleve, C. [Dipartimento di Matematica e Fisica ' E. De Giorgi' dell' Universita del Salento, via per Arnesano, I-73100 Lecce (Italy); Bi, X. J.; Cao, Z.; Chen, S. Z.; Chen, Y. [Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, P.O. Box 918, 100049 Beijing (China); Bolognino, I. [Dipartimento di Fisica Nucleare e Teorica dell' Universita di Pavia, via Bassi 6, I-27100 Pavia (Italy); Branchini, P.; Budano, A. [Istituto Nazionale di Fisica Nucleare, Sezione di Roma Tre, via della Vasca Navale 84, I-00146 Roma (Italy); Calabrese Melcarne, A. K. [Istituto Nazionale di Fisica Nucleare-CNAF, Viale Berti-Pichat 6/2, I-40127 Bologna (Italy); Camarri, P. [Dipartimento di Fisica dell' Universita di Roma ' Tor Vergata' , via della Ricerca Scientifica 1, I-00133 Roma (Italy); Cardarelli, R. [Istituto Nazionale di Fisica Nucleare, Sezione di Roma Tor Vergata, via della Ricerca Scientifica 1, I-00133 Roma (Italy); Cattaneo, C. [Istituto Nazionale di Fisica Nucleare, Sezione di Pavia, via Bassi 6, I-27100 Pavia (Italy); Chen, T. L. [Tibet University, 850000 Lhasa, Xizang (China); Creti, P. [Istituto Nazionale di Fisica Nucleare, Sezione di Lecce, via per Arnesano, I-73100 Lecce (Italy); Cui, S. W. [Hebei Normal University, Shijiazhuang 050016, Hebei (China); Dai, B. Z. [Yunnan University, 2 North Cuihu Rd., 650091 Kunming, Yunnan (China); D' Ali Staiti, G., E-mail: chensz@ihep.ac.cn [Dipartimento di Fisica e Tecnologie Relative, Universita degli Studi di Palermo, Viale delle Scienze, Edificio 18, I-90128 Palermo (Italy); Collaboration: ARGO-YBJ Collaboration; and others

    2012-10-10

    As one of the brightest active blazars in both X-ray and very high energy {gamma}-ray bands, Mrk 501, is very useful for physics associated with jets from active galactic nuclei. The ARGO-YBJ experiment has monitored Mrk 501 for {gamma}-rays above 0.3 TeV since 2007 November. The largest flare since 2005 was observed from 2011 October and lasted until about 2012 April. In this paper, a detailed analysis of this event is reported. During the brightest {gamma}-ray flaring episodes from 2011 October 17 to November 22, an excess of the event rate over 6{sigma} is detected by ARGO-YBJ in the direction of Mrk 501, corresponding to an increase of the {gamma}-ray flux above 1 TeV by a factor of 6.6 {+-} 2.2 from its steady emission. In particular, the {gamma}-ray flux above 8 TeV is detected with a significance better than 4{sigma}. Based on time-dependent synchrotron self-Compton (SSC) processes, the broadband energy spectrum is interpreted as the emission from an electron energy distribution parameterized with a single power-law function with an exponential cutoff at its high-energy end. The average spectral energy distribution for the steady emission is well described by this simple one-zone SSC model. However, the detection of {gamma}-rays above 8 TeV during the flare challenges this model due to the hardness of the spectra. Correlations between X-rays and {gamma}-rays are also investigated.

  18. Thermoluminescence response of K{sub 2}Ca{sub 2}(SO{sub 4}){sub 3} nanophosphor Co-doped with Eu and Ce for gamma ray dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Patil, B. J. [Dept. of Physics, Abasaheb Garware College, Pune-411004 (India); Bhadane, Mahesh S.; Dahiwale, S. S.; Bhoraskar, V. N.; Dhole, S. D., E-mail: sanjay@physics.unipune.ac.in [Department of Physics, University of Pune, Pune 411007 (India); Mandlik, N. T. [Dept. of Physics, Fergusson College, Pune-411004 (India); Kulkarni, M. S. [Radiation Safety Systems Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Bhatt, B. C. [Radiological Physics and Advisory Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

    2015-06-24

    K{sub 2}Ca{sub 2}(SO{sub 4}){sub 3} nanophosphors co-doped with Eu and Ce were synthesized by the chemical co-precipitation method. These samples were further annealed at 700 °C structural reformation. The structural and morphological characteristics were studied using XRD and TEM techniques. The particle size calculated from XRD spectra was around 35 nm. The as synthesized sample shows cubic structure annealed at 700 °C. The as synthesized and annealed sample of K{sub 2}Ca{sub 2}(SO{sub 4}){sub 3}: EuCe were irradiated with Co{sup 60} gamma rays for the doses from 2Gy to 1kGy. The TL characteristic sample of co-doped were studied for the dosimetric application by gamma radiation. The TL spectrum of annealed sample has single peaked at 160 °C. The Eu doped sample has a high TL sensitivity than Ce doped sample. But after co-doping with Eu and Ce, TL intensity observed to be decreased. The decrees in TL peak intensity of the phosphor on co-doping of Eu and Ce gives an insight into the emission mechanism of the phosphor which involves energy transfer from Eu to Ce. The TL response of all the samples were found to be linear for the dose from 2 Gy to 1 KGy. Therefore, K{sub 2}Ca{sub 2}(SO{sub 4}){sub 3}: EuCe nanophosphor can be used for the measurement of high dose of gamma radiation.

  19. Holmium-166m: multi-gamma standard to determine the activity of radionuclides in semiconductor detectors

    International Nuclear Information System (INIS)

    Bernardes, Estela Maria de Oliveira

    2001-01-01

    The efficiency and calibration curves as function of gamma-ray energy for a germanium detector are usually established by using many standard gamma ray sources of radionuclides decaying with few gamma rays or radionuclides having complex decay scheme, as 152 Eu or 133 Ba. But these radionuclides cannot be used alone, because they have a few gamma lines with high intensity and these lines have a irregular distribution in the energy spectrum. 166m Ho is found to be a convenient single source for such calibration, because it decays by β - with subsequent emission of about 40 strong and well distributed gamma lines between 80 and 1500 keV. Moreover, its long half - life (1200 years) and X-rays characteristics between 40 and 50 keV makes it a good standard for calibration of germanium detectors. However, it is necessary to know with accuracy and precision the gamma ray intensities of their main lines, due to the fact that literature has showed discrepant values. Then, a methodology to determine the emission probability of its main lines is proposed by means of combined use of gamma spectrometry and coincidence 4πβ -γ techniques. The experimental results show consistence to the others authors, with lower or compatible uncertainties. (author)

  20. Dose calculation for 40K ingestion in samples of beans using spectrometry and MCNP

    International Nuclear Information System (INIS)

    Garcez, R.W.D.; Lopes, J.M.; Silva, A.X.; Domingues, A.M.; Lima, M.A.F.

    2014-01-01

    A method based on gamma spectroscopy and on the use of voxel phantoms to calculate dose due to ingestion of 40 K contained in bean samples are presented in this work. To quantify the activity of radionuclide, HPGe detector was used and the data entered in the input file of MCNP code. The highest value of equivalent dose was 7.83 μSv.y -1 in the stomach for white beans, whose activity 452.4 Bq.Kg -1 was the highest of the five analyzed. The tool proved to be appropriate when you want to calculate the dose in organs due to ingestion of food. (author)

  1. High-energy emission from bright gamma-ray bursts using Fermi

    Energy Technology Data Exchange (ETDEWEB)

    Bissaldi, Elisabetta

    2010-05-25

    Among the scientific objectives of one of the present NASA missions, the Fermi Gamma-ray Space Telescope (FGST), is the study of gamma-ray bursts (GRBs). Fermi's payload comprises two science instruments, the Large Area Telescope (LAT) and the Gamma-Ray Burst Monitor (GBM). GBM was designed to detect and localize bursts for the Fermi mission. By means of an array of 12 NaI(Tl) (8 keV to 1 MeV) and two BGO (0.2 to 40 MeV) scintillation detectors, GBM extends the energy range (20 MeV to > 300 GeV) of the LAT instrument into the traditional range of current GRB databases. The physical detector response of the GBM instrument to GRBs has been determined with the help of Monte Carlo simulations, which are supported and verified by on-ground individual detector calibration measurements. The GBM detectors have been calibrated from 10 keV to 17.5 MeV using various gamma sources, and the detector response has been derived by simulations over the entire energy range (8 keV to 40 MeV) using GEANT. The GBM instrument has been operating successfully in orbit since June 11, 2008. The total trigger count from the time GBM triggering was enabled in July 2008 through December 2009 is 655, and about 380 of these triggers were classified as GRBs. Moreover, GBM detected several bursts in common with the LAT. These amazing detections mainly fulfill the primary science goal of GBM, which is the joint analysis of spectra and time histories of GRBs observed by both Fermi instruments. For every trigger, GBM provides near-real time on-board burst locations to permit repointing of the spacecraft and to obtain LAT observations of delayed emission from bursts. GBM and LAT refined locations are rapidly disseminated to the scientific community, often permitting extensive multiwavelength follow-up observations by NASA's Swift mission or other space- based observatories, and by numerous ground-based telescopes, thus allowing redshift determinations. Calculations of LAT upper limits are

  2. High-energy emission from bright gamma-ray bursts using Fermi

    International Nuclear Information System (INIS)

    Bissaldi, Elisabetta

    2010-01-01

    Among the scientific objectives of one of the present NASA missions, the Fermi Gamma-ray Space Telescope (FGST), is the study of gamma-ray bursts (GRBs). Fermi's payload comprises two science instruments, the Large Area Telescope (LAT) and the Gamma-Ray Burst Monitor (GBM). GBM was designed to detect and localize bursts for the Fermi mission. By means of an array of 12 NaI(Tl) (8 keV to 1 MeV) and two BGO (0.2 to 40 MeV) scintillation detectors, GBM extends the energy range (20 MeV to > 300 GeV) of the LAT instrument into the traditional range of current GRB databases. The physical detector response of the GBM instrument to GRBs has been determined with the help of Monte Carlo simulations, which are supported and verified by on-ground individual detector calibration measurements. The GBM detectors have been calibrated from 10 keV to 17.5 MeV using various gamma sources, and the detector response has been derived by simulations over the entire energy range (8 keV to 40 MeV) using GEANT. The GBM instrument has been operating successfully in orbit since June 11, 2008. The total trigger count from the time GBM triggering was enabled in July 2008 through December 2009 is 655, and about 380 of these triggers were classified as GRBs. Moreover, GBM detected several bursts in common with the LAT. These amazing detections mainly fulfill the primary science goal of GBM, which is the joint analysis of spectra and time histories of GRBs observed by both Fermi instruments. For every trigger, GBM provides near-real time on-board burst locations to permit repointing of the spacecraft and to obtain LAT observations of delayed emission from bursts. GBM and LAT refined locations are rapidly disseminated to the scientific community, often permitting extensive multiwavelength follow-up observations by NASA's Swift mission or other space- based observatories, and by numerous ground-based telescopes, thus allowing redshift determinations. Calculations of LAT upper limits are mainly based

  3. A multi-frequency analysis of possible dark matter contributions to M31 gamma-ray emissions

    Energy Technology Data Exchange (ETDEWEB)

    Beck, G.; Colafrancesco, S., E-mail: geoffrey.beck@wits.ac.za, E-mail: sergio.colafrancesco@wits.ac.za [School of Physics, University of the Witwatersrand, Private Bag 3, WITS-2050, Johannesburg (South Africa)

    2017-10-01

    We examine the possibility of a dark matter (DM) contribution to the recently observed gamma-ray spectrum seen in the M31 galaxy. In particular, we apply limits on Weakly Interacting Massive Particle DM annihilation cross-sections derived from the Coma galaxy cluster and the Reticulum II dwarf galaxy to determine the maximal flux contribution by DM annihilation to both the M31 gamma-ray spectrum and that of the Milky-Way Galactic Centre. We limit the energy range between 1 and 12 GeV in M31 and Galactic Centre spectra due to the limited range of former's data, as well as to encompass the high-energy gamma-ray excess observed in the latter target. In so doing, we will make use of Fermi-LAT data for all mentioned targets, as well as diffuse radio data for the Coma cluster. The multi-target strategy using both Coma and Reticulum II to derive cross-section limits, as well as multi-frequency data, ensures that our results are robust against the various uncertainties inherent in modelling of indirect DM emissions. Our results indicate that, when a Navarro-Frenk-White (or shallower) radial density profile is assumed, severe constraints can be imposed upon the fraction of the M31 and Galactic Centre spectra that can be accounted for by DM, with the best limits arising from cross-section constraints from Coma radio data and Reticulum II gamma-ray limits. These particular limits force all the studied annihilation channels to contribute 1% or less to the total integrated gamma-ray flux within both M31 and Galactic Centre targets. In contrast, considerably more, 10−100%, of the flux can be attributed to DM when a contracted Navarro-Frenk-White profile is assumed. This demonstrates how sensitive DM contributions to gamma-ray emissions are to the possibility of cored profiles in galaxies. The only channel consistently excluded for all targets and profiles (except for ∼ 10 GeV WIMPs) is the direct annihilation into photons. Finally, we discuss the ramifications of

  4. Gamma knife treatment for refractory epilepsy in seizure focus localized by positron emission tomography/CT★

    Science.gov (United States)

    Bai, Xia; Wang, Xuemei; Wang, Hongwei; Zhao, Shigang; Han, Xiaodong; Hao, Linjun; Wang, Xiangcheng

    2012-01-01

    A total of 80 patients with refractory epilepsy were recruited from the Inner Mongolia Medical College Affiliated Hospital. The foci of 60% of the patients could be positioned using a combined positron emission tomography/CT imaging modality. Hyper- and hypometabolism foci were examined as part of this study. Patients who had abnormal metabolism in positron emission tomography/CT imaging were divided into intermittent-phase group and the seizure-phase group. The intermittent-phase group was further divided into a single-focus group and a multiple-foci group according to the number of seizure foci detected by imaging. Following gamma knife treatment, seizure frequency was significantly lower in the intermittent-phase group and the seizure-phase group. Wieser’s classification reached Grade I or II in nearly 40% of patients. Seizure frequency was significantly lower following treatment, but Wieser’s classification score was significantly higher in the seizure-phase group compared with the intermittent-phase group. Seizure frequency was significantly lower following treatment in the single-focus group, but Wieser’s classification score was significantly higher in the single-focus group as compared with the multiple-foci group. PMID:25317147

  5. Measurements of psi -> K-Lambda(Xi)over-bar(+) + c.c. and psi -> gamma K-Lambda(Xi)over-bar(+) + c.c.

    NARCIS (Netherlands)

    Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Ferroli, R. Baldini; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Bertani, M.; Bettoni, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Bondarenko, O.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, H. Y.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, X.; Chen, X. R.; Chen, Y. B.; Cheng, H. P.; Chu, X. K.; Cibinetto, G.; Cronin-Hennessy, D.; Dai, H. L.; Dai, J. P.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; De Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Duan, S. X.; Duan, P. F.; Fan, J. Z.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Fava, L.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. Y.; Gao, Y.; Gao, Z.; Garzia, I.; Geng, C.; Goetzen, K.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, Y.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Han, Y. L.; Hao, X. Q.; Harris, F. A.; He, K. L.; He, Z. Y.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. M.; Huang, G. S.; Huang, H. P.; Huang, J. S.; Huang, X. T.; Huang, Y.; Hussain, T.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. L.; Jiang, L. W.; Jiang, X. S.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X. L.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Kliemt, R.; Kloss, B.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kuehn, W.; Kupsc, A.; Lai, W.; Lange, J. S.; Lara, M.; Larin, P.; Leng, C.; Li, C. H.; Li, Cheng; Li, D. M.; Li, F.; Li, G.; Li, H. B.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P. R.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. M.; Li, X. N.; Li, X. Q.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B. J.; Liu, C. X.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, L. D.; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, X. X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqiang; Liu, Zhiqing; Loehner, H.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, R. Q.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lv, M.; Lyu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, Q. M.; Ma, S.; Ma, T.; Ma, X. N.; Ma, X. Y.; Maas, F. E.; Maggiora, M.; Malik, Q. A.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales, C. Morales; Moriya, K.; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Pu, Y. N.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, N.; Qin, X. S.; Qin, Y.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Ren, H. L.; Ripka, M.; Rong, G.; Ruan, X. D.; Santoro, V.; Sarantsev, A.; Savrie, M.; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Song, W. M.; Song, X. Y.; Sosio, S.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Tiemens, M.; Toth, D.; Ullrich, M.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, Q. J.; Wang, S. G.; Wang, W.; Wang, X. F.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Weber, T.; Wei, D. H.; Wei, J. B.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, Z.; Xia, L. G.; Xia, Y.; Xiao, D.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. X.; Yang, L.; Yang, Y.; Yang, Y. X.; Ye, H.; Ye, M.; Ye, M. H.; Yin, J. H.; Yu, B. X.; Yu, C. X.; Yu, H. W.; Yu, J. S.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J. J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. H.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. T.; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, H. S.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. W.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, W. J.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, Li; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zotti, L.; Zou, B. S.; Zou, J. H.

    2015-01-01

    Using a sample of 1.06 x 10(8) psi(3686) events produced in e(+)e(-) collisions at root s = 3.686 GeV and collected with the BESIII detector at the BEPCII collider, we present studies of the decays psi(3686) -> K-Lambda(Xi) over bar (+) + c.c. and psi(3686) -> gamma K-Lambda(Xi) over bar (+) + c.c.

  6. Committed dose assessment based on background outdoor gamma exposure in Chihuahua City, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Luevano G, S.; Perez T, A.; Pinedo A, C.; Renteria V, M. [Universidad Autonoma de Chihuahua, Facultad de Zootecnia y Ecologia, Perif. Francisco R. Almada Km 1, 31415 Chihuahua, Chih. (Mexico); Carrillo F, J.; Montero C, M. E., E-mail: mrenteria@uach.mx [Centro de Investigacion en Materiales Avanzados, Miguel de Cervantes 120, 31136 Chihuahua, Chih. (Mexico)

    2015-10-15

    Full text: Determining ionizing radiation in a geographic area serves to assess its effects on populations health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the committed dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, annual effective dose, and the lifetime cancer risk, 48 sampling points were randomly selected along the Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Muller counter. At the same sites, 48 soil samples were taken to obtain the activity concentrations of {sup 226}Ra, {sup 232}Th, {sup 40}K and their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Outdoor gamma dose rates ranged from 56 to 193 n Gy h{sup -1}. Results indicated that lifetime effective dose to inhabitants of Chihuahua City is in average of 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of activity concentrations in soil were 51.8, 73.1, and 1096.5 Bq kg{sup -1}, of {sup 226}Ra, {sup 232}Th and {sup 40}K, respectively. From the analysis of the spatial distribution of {sup 232}Th, {sup 226}Ra, and {sup 40}K is to north, to north-center, and to south of city, respectively. In conclusion, natural background gamma dose received by inhabitants of Chihuahua City is high and mainly due to geological characteristics of the zone. (Author)

  7. 40 CFR 76.13 - Compliance and excess emissions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Compliance and excess emissions. 76.13 Section 76.13 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.13 Compliance and excess emissions...

  8. Dose calculation for {sup 40}K ingestion in samples of beans using spectrometry and MCNP; Calculo de dose devido a ingestao de {sup 40}K em amostras de feijao utilizando espectrometria e MCNP

    Energy Technology Data Exchange (ETDEWEB)

    Garcez, R.W.D.; Lopes, J.M.; Silva, A.X., E-mail: marqueslopez@yahoo.com.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/PEN/UFRJ), Rio de Janeiro, RJ (Brazil). Centro de Tecnologia; Domingues, A.M. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Instituto de Fisica; Lima, M.A.F. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Instituto de Biologia

    2014-07-01

    A method based on gamma spectroscopy and on the use of voxel phantoms to calculate dose due to ingestion of {sup 40}K contained in bean samples are presented in this work. To quantify the activity of radionuclide, HPGe detector was used and the data entered in the input file of MCNP code. The highest value of equivalent dose was 7.83 μSv.y{sup -1} in the stomach for white beans, whose activity 452.4 Bq.Kg{sup -1} was the highest of the five analyzed. The tool proved to be appropriate when you want to calculate the dose in organs due to ingestion of food. (author)

  9. 226Ra, 228Ra and 40K in scales formed in boilers of industrial installations

    International Nuclear Information System (INIS)

    Poggi, Claudia M. Braga; Farias, Emerson Emiliano G. de; Hazin, Clovis A.; Gazineu, Maria Helena P.; Universidade Catolica de Pernambuco

    2011-01-01

    Many industrial processes involve the production of steam in boilers, which is sent through pipes to machines and other equipment used in different sectors of the installations. The water commonly used in these processes is groundwater, which generally has high concentrations of calcium and magnesium salts, that can co-precipitate with naturally occurring radioactive elements such as 226 Ra and 228 Ra creating radioactive scales, which are deposited in pipes, thus decreasing the efficiency of steam production. In addition, 40 K that is present in all soils and rocks with a concentration of about 0.012% of natural potassium can also be concentrated in these scales. No data was found in literature relating to radionuclides present in the scales formed on boilers in general. In this context, the purpose of this work was to determine concentrations of 226 Ra, 228 Ra and 40 K, in scales generated inside boilers from different industries in the cities of Caruaru, Paulista and Goiana, Pernambuco. Determination of the radionuclides concentration was performed by gamma spectrometry with an HPGe detector, calculating their specific activities. Activity concentrations of 226 Ra were in the range of -1 and 228 Ra activity concentrations varied from 1 . Activity concentrations of 40 K were in the range of -1 . All these activity concentrations were lower than the limits established by the Brazilian Nuclear Energy Commission of for this type of matrix. (author)

  10. 40 CFR 89.120 - Compliance with emission standards.

    Science.gov (United States)

    2010-07-01

    ...). (c) For each nonroad engine family, except Tier 1 engine families with rated power at or above 37 kW... representing an engine family have emissions less than or equal to each emission standard, that family complies with the emission standards. (b) If any test engine representing an engine family has emissions greater...

  11. Spin-polarized x-ray emission of 3d transition-metal ions : A comparison via K alpha and K beta detection

    NARCIS (Netherlands)

    Wang, Xin; deGroot, F.M.F.; Cramer, SP

    1997-01-01

    This paper demonstrates that spin-polarized x-ray-excitation spectra can be obtained using K alpha emission as well as K beta lines. A spin-polarized analysis of K alpha x-ray emission and the excitation spectra by K alpha detection on a Ni compound is reported. A systematic analysis of the

  12. Measuring $\\gamma$ at LHCb with $B^{+-} \\to (\\overline{D^{0}}/D^{0})(K\\pi,KK,\\pi\\pi) K^{+-}$ Decays

    CERN Document Server

    Patel, M

    2008-01-01

    A method of extracting the CKM angle gamma from the decay rates of the processes B+- -> (D0/D~0)(Kpi,KK,pipi) K+- is presented. Knowledge of the relative D0/D~0 two-body branching fractions and the selection efficiencies are used to reduce the number of unknown parameters. From one nominal year of LHCb data-taking (2fb-1 integrated luminosity), a precision on gamma in the range 8.2-9.6 degrees is expected, depending on the value of the unknown strong phase in the Kpi decay.

  13. Clustering of gamma-ray burst types in the Fermi GBM catalogue: indications of photosphere and synchrotron emissions during the prompt phase

    Science.gov (United States)

    Acuner, Zeynep; Ryde, Felix

    2018-04-01

    Many different physical processes have been suggested to explain the prompt gamma-ray emission in gamma-ray bursts (GRBs). Although there are examples of both bursts with photospheric and synchrotron emission origins, these distinct spectral appearances have not been generalized to large samples of GRBs. Here, we search for signatures of the different emission mechanisms in the full Fermi Gamma-ray Space Telescope/GBM (Gamma-ray Burst Monitor) catalogue. We use Gaussian Mixture Models to cluster bursts according to their parameters from the Band function (α, β, and Epk) as well as their fluence and T90. We find five distinct clusters. We further argue that these clusters can be divided into bursts of photospheric origin (2/3 of all bursts, divided into three clusters) and bursts of synchrotron origin (1/3 of all bursts, divided into two clusters). For instance, the cluster that contains predominantly short bursts is consistent of photospheric emission origin. We discuss several reasons that can determine which cluster a burst belongs to: jet dissipation pattern and/or the jet content, or viewing angle.

  14. 40 CFR 1042.715 - Banking emission credits.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Banking emission credits. 1042.715 Section 1042.715 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION..., Banking, and Trading for Certification § 1042.715 Banking emission credits. (a) Banking is the retention...

  15. 40 CFR 52.2424 - Motor vehicle emissions budgets.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Motor vehicle emissions budgets. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Virginia § 52.2424 Motor vehicle emissions budgets. (a) Motor vehicle emissions budget for the Hampton Roads maintenance area adjusting the...

  16. Use of gamma ray spectroscopy measurements for assessment of the average effective dose from the analysis of 226Ra, 232Th and 40K in soil samples

    International Nuclear Information System (INIS)

    Mehra, Rohit; Singh, Surinder

    2008-01-01

    The activity concentrations of soil samples collected from different locations of Ludhiana and Patiala districts of Punjab were determined by using HPGe detector based on high-resolution gamma spectrometry system. The range of activity concentrations of 226 Ra, 232 Th and 40 K in the soil from the studied areas varies from 23.32 Bq kg -1 to 43.64 Bq kg -1 , 104.23 Bq kg -1 to 148.21 Bq kg -1 and 289.83 Bq kg -1 to 394.41 Bq kg -1 with overall mean values of 32 Bq kg -1 , 126 Bq kg -1 and 348 Bq kg -1 respectively. The absorbed dose rate calculated from activity concentration of 226 Ra, 232 Th and 40 K ranges between 10.75 and 20.12, 64.93 and 92.33, and 11.99 and 16.32 n Gy h -1 , respectively. The total absorbed dose in the study area ranges from 91.35 n Gy h -1 to 119.76 n Gy h -1 with an average value of 107.97 n Gy h -1 . The calculated values of external hazard index (H ex ) for the soil samples of the study area range from 0.55 to 0.72. Since these values are lower than unity, therefore, according to the Radiation Protection 112 (European Commission, 1999) report, soil from these regions is safe and can be used as a construction material without posing any significant radiological threat to population. The concentration of 232 Th in soil samples of Malwa region of Punjab are higher than the world figures reported in UNSCEAR (2000). However, the concentrations for 226 Ra is very much comparable and concentration of 40 K are lower than world figures. The results obtained have shown that the indoor and outdoor effective dose due to natural radioactivity of soil samples is lower than the average national and world recommended value of 1.0 mSv.Y -1 . These values reported for radium content in soils of study area are generally low as compared to the values reported for radium concentration in soils of Himachal Pradesh. (author)

  17. A LINGERING NON-THERMAL COMPONENT IN THE GAMMA-RAY BURST PROMPT EMISSION: PREDICTING GeV EMISSION FROM THE MeV SPECTRUM

    International Nuclear Information System (INIS)

    Basak, Rupal; Rao, A. R.

    2013-01-01

    The high-energy GeV emission of gamma-ray bursts (GRBs) detected by Fermi/LAT has a significantly different morphology compared to the lower energy MeV emission detected by Fermi/GBM. Though the late-time GeV emission is believed to be synchrotron radiation produced via an external shock, this emission as early as the prompt phase is puzzling. A meaningful connection between these two emissions can be drawn only by an accurate description of the prompt MeV spectrum. We perform a time-resolved spectroscopy of the Gamma-ray Burst Monitor (GBM) data of long GRBs with significant GeV emission, using a model consisting of two blackbodies and a power law. We examine in detail the evolution of the spectral components and find that GRBs with high GeV emission (GRB 090902B and GRB 090926A) have a delayed onset of the power-law component in the GBM spectrum, which lingers at the later part of the prompt emission. This behavior mimics the flux evolution in the Large Area Telescope (LAT). In contrast, bright GBM GRBs with an order of magnitude lower GeV emission (GRB 100724B and GRB 091003) show a coupled variability of the total and the power-law flux. Further, by analyzing the data for a set of 17 GRBs, we find a strong correlation between the power-law fluence in the MeV and the LAT fluence (Pearson correlation: r = 0.88 and Spearman correlation: ρ = 0.81). We demonstrate that this correlation is not influenced by the correlation between the total and the power-law fluences at a confidence level of 2.3σ. We speculate the possible radiation mechanisms responsible for the correlation

  18. Distribution of 226Ra, 232Th and 40K in soils and sugar cane crops at Corumbatai river basin, Sao Paulo State, Brazil

    International Nuclear Information System (INIS)

    Tomazini da Conceicao, Fabiano; Bonotto, Daniel Marcos; Jimenez-Rueda, Jairo Roberto; Frutuoso Roveda, Jose Arnaldo

    2009-01-01

    The common use of phosphate fertilizers NPK and amendments in sugar cane crops in Brazilian agriculture may increase the 226 Ra, 232 Th and 40 K activity concentrations in soils and their availability for plants and human food chain. Thus, the main aim of this study was to evaluate the distribution of 226 Ra, 232 Th and 40 K in soils and sugar cane crops in the Corumbatai river basin, Sao Paulo State, Brazil. The gamma spectrometry was utilized to measure the 226 Ra, 232 Th and 40 K activity concentration in all samples. The soil-to-sugar cane transfer factors (TF) were quantified using the ratio between the radionuclide activity concentration in sugar cane and its activity concentration in soil. The results show that, although radionuclides incorporated in phosphate fertilizers and amendments are annually added in the sugar cane crops, if utilized in accordance with the recommended rates, their use does not lead to hazards levels in soils. The soil-to-sugar cane transfer of radionuclides occurred in the following order 40 K> 226 Ra> 232 Th. Therefore, under these conditions, radionuclides intake through consumption of sugar is not hazardous to human health.

  19. Initial Search for Triggered Gamma Emission from {sup 178}Hf{sup m2} Using the YSU Miniball Array

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, J. J.; Burnett, J.; Drummond, T.; Lepak, J.; Propri, R.; Smith, D. [Youngstown State University, Department of Physics and Astronomy, Center for Photon-Induced Processes (United States); Karamian, S. A.; Adam, J. [Joint Institute for Nuclear Research (Russian Federation); Stedile, F. [Universitaet Stuttgart, Institut fuer Strahlenphysik (Germany); Agee, F. J. [Air Force Office of Scientific Research, AFOSR/NE (United States)

    2002-11-15

    Experiments with the long-lived, high-K isomer {sup 178}Hf{sup m2} have been recognized as intriguing tests of multi-quasiparticle state structures and their interactions with external radiation. A triggered release of the energy stored by this isomer, 2.5 MeV per nucleus or 1.2 GJ/gram, in the form of a gamma-ray burst might prove valuable for numerous applications. The observation of 'accelerated' decay of {sup 178}Hf{sup m2} during irradiation by 90-keV bremsstrahlung has already been reported, but with poor statistical accuracy due to the experimental approach. That approach employed single Ge detectors to seek increases in the areas of peaks at energies corresponding to transitions in the spontaneous decay of the isomer. The need for better quality data to confirm those results has motivated the development of improved detection concepts. One such concept was utilized here to perform an initial search for low-energy (<20 keV) triggered gamma emission from {sup 178}Hf{sup m2} using the YSU miniball detector array.

  20. Use of LabSOCS for determination of specific concentrations of {sup 40}K, {sup 238}U and {sup 232}Th in fertilizer samples; Uso de LabSOCS no calculo da eficiencia de detecao para determinacao da concentracao especifica de {sup 40}K, {sup 238}U e {sup 232}Th em amostras de fertilizantes

    Energy Technology Data Exchange (ETDEWEB)

    Garcez, Ricardo Washington Dutra; Lopes, Jose Marques; Silva, Ademir Xavier da, E-mail: rgarcez@con.ufrj.br, E-mail: marqueslopez@yahoo.com.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Domingues, Alessandro Mariano; Lima, Marco Frota, E-mail: slessandrodomingues@fisica.if.uff.br, E-mail: marcofrotalima@yahoo.com.br [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Instituto de Biologia

    2015-07-01

    Use of fertilizer is an established practice worldwide to promote agricultural productivity increased without increasing the planted area, resulting in native forests protection and increase of the food availability. Some kinds of fertilizer have in their chemical composition some radionuclides due the origin of its feedstock, such as {sup 238}U, the {sup 232}Th, and their descendants, beyond {sup 40}K. Knowledge of the radioactivity levels in the environment is great importance to know the gamma radiation dose that the human being is exposed. For identification and quantitation of radionuclides, it was used gamma spectrometry where HPGe detector was used to obtain the spectra, and LabSOCS software for calculating the detection efficiency for each energy. The values of {sup 232}Th specific concentrations ranged from 4.1 to 368.1 Bq.Kg{sup -1} , the values of {sup 238}U specific concentrations ranged from 16.0 to 647.7 Bq.Kg{sup -1} and {sup 40}K specific concentrations ranged from 19.1 to 12713 Bq.Kg{sup -1} . Concentrations of values are consistent with those found in literature. (author)

  1. Evaluation of Ra-226, Th-232 and K-40 activities concentrations and radium equivalent index in several Brazilian economic wall paints

    International Nuclear Information System (INIS)

    Fonseca, Leandro M.; Pecequilo, Brigitte R.S.

    2015-01-01

    The titanium dioxide used as the white pigment in paints is produced from the processing of ilmenite minerals. As monazite, the main ilmenite radioactive contaminant, contains 1 to 20% thorium dioxide and also some uranium traces, so, eventually, wall paints can contain radioactivity. Activity concentrations of the naturally occurring radionuclides 226 Ra, 232 Th and 40 K were determined in 15 Brazilian economic wall paints samples, by high resolution gamma-ray spectrometry. The activities concentrations in the studied samples ranged from 1.3 ± 0.2 Bq/kg to 23.4 ± 0.7 Bq/kg for 226 Ra; from 2.5 ± 0.4 Bq/kg to 45.8 ± 1.5 Bq/kg for 232 Th and from 5.8 ± 2.1 Bq/kg to 157 ± 22 Bq/kg for 40 K. The radium equivalent index, calculated from the 226 Ra, 232 Th and 40 K concentrations, varied from 1.30 Bq/kg up to 95.9 Bq/kg, below the value of 370 Bq/kg recommended by OECD for a safety use in residential building applications. (author)

  2. FERMI OBSERVATIONS OF HIGH-ENERGY GAMMA-RAY EMISSION FROM GRB 090217A

    International Nuclear Information System (INIS)

    Ackermann, M.; Ajello, M.; Bechtol, K.; Berenji, B.; Blandford, R. D.; Borgland, A. W.; Bouvier, A.; Baldini, L.; Bellazzini, R.; Bregeon, J.; Brez, A.; Ballet, J.; Barbiellini, G.; Baring, M. G.; Bastieri, D.; Bhat, P. N.; Briggs, M. S.; Bissaldi, E.; Bonamente, E.; Brigida, M.

    2010-01-01

    The Fermi observatory is advancing our knowledge of gamma-ray bursts (GRBs) through pioneering observations at high energies, covering more than seven decades in energy with the two on-board detectors, the Large Area Telescope (LAT) and the Gamma-ray Burst Monitor (GBM). Here, we report on the observation of the long GRB 090217A which triggered the GBM and has been detected by the LAT with a significance greater than 9σ. We present the GBM and LAT observations and on-ground analyses, including the time-resolved spectra and the study of the temporal profile from 8 keV up to ∼1 GeV. All spectra are well reproduced by a Band model. We compare these observations to the first two LAT-detected, long bursts GRB 080825C and GRB 080916C. These bursts were found to have time-dependent spectra and exhibited a delayed onset of the high-energy emission, which are not observed in the case of GRB 090217A. We discuss some theoretical implications for the high-energy emission of GRBs.

  3. 40 CFR 52.244 - Motor vehicle emissions budgets.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Motor vehicle emissions budgets. 52.244... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.244 Motor vehicle emissions budgets. (a) Approval of the motor vehicle emissions budgets for the following ozone rate-of-progress and...

  4. Absolute disintegration rate and 320 keV {gamma}-ray emission probability of {sup 51}Cr

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, M.C.M. de [Laboratorio Nacional de Metrologia das Radiacoes Ionizantes /Instituto de Radioprotecao e Dosimetria (LNMRI/ IRD), Avenida Salvador Allende, s/no. Recreio-Rio de Janeiro, CEP 22780-160 (Brazil)], E-mail: candida@ird.gov.br; Iwahara, A.; Poledna, R.; Silva, C.J. da; Delgado, J.U. [Laboratorio Nacional de Metrologia das Radiacoes Ionizantes /Instituto de Radioprotecao e Dosimetria (LNMRI/ IRD), Avenida Salvador Allende, s/no. Recreio-Rio de Janeiro, CEP 22780-160 (Brazil)

    2007-09-21

    This work describes the procedures for determining absolutely the {sup 51}Cr disintegration rate by using the 4{pi}{beta}-{gamma} coincidence and anti-coincidence counting and the sum-peak methods. A 4''x4''-NaI(Tl) scintillation detector was used in the {gamma}- channel of the 4{pi}{beta}-{gamma} coincidence system for {gamma}-ray counting. In the {beta}-channel, a 4{pi} gas flow proportional counter was used for counting of characteristic X-rays and Auger electrons originating from the electron capture events of the {sup 51}Cr decay scheme. Gamma spectrometry measurements by high-pure planar and coaxial germanium detectors were performed in the sum-peak method and in the determination of the 320 keV {gamma}-emission probability of {sup 51}Cr. This latter determined value agrees with the recent values found in the literature, confirming the reliability of the three methods used in this work for the disintegration rate measurements.

  5. Search for Gamma-Ray Emission from the Coma Cluster with Six Years of Fermi-LAT Data

    Science.gov (United States)

    Ackermann, M.; Ajello, M.; Albert, A.; Atwood, W. B.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; hide

    2016-01-01

    We present results from gamma-ray observations of the Coma cluster incorporating six years of Fermi-LAT data and the newly released 'Pass 8' event-level analysis. Our analysis of the region reveals low-significance residual structures within the virial radius of the cluster that are too faint for a detailed investigation with the current data. Using a likelihood approach that is free of assumptions on the spectral shape we derive upper limits on the gamma-ray flux that is expected from energetic particle interactions in the cluster. We also consider a benchmark spatial and spectral template motivated by models in which the observed radio halo is mostly emission by secondary electrons. In this case, the median expected and observed upper limits for the flux above 100 MeV are 1.7 x 10(exp -9) ph cm(exp -2) s(exp -1) and 5.2 x 10(exp -9) ph cm(exp -2) s(exp -1) respectively (the latter corresponds to residual emission at the level of 1.8sigma). These bounds are comparable to or higher than predicted levels of hadronic gamma-ray emission in cosmic-ray (CR) models with or without reacceleration of secondary electrons, although direct comparisons are sensitive to assumptions regarding the origin and propagation mode of CRs and magnetic field properties. The minimal expected gamma-ray flux from radio and star-forming galaxies within the Coma cluster is roughly an order of magnitude below the median sensitivity of our analysis.

  6. Role of high-spin hyperon resonances in the reaction of $\\gamma p \\to K^+ K^+ \\Xi^-$

    Energy Technology Data Exchange (ETDEWEB)

    J. Ka Shing Man, Yongseok Oh, K. Nakayama

    2011-05-01

    The recent data taken by the CLAS Collaboration at the Thomas Jefferson National Accelerator Facility for the reaction of $\\gamma p \\to K^+ K^+ \\Xi^-$ are reanalyzed within a relativistic meson-exchange model of hadronic interactions. The present model is an extension of the one developed in an earlier work by Nakayama, Oh, and Haberzettl [Phys. Rev. C 74, 035205 (2006)]. In particular, the role of the spin-5/2 and -7/2 hyperon resonances, which were not included in the previous model, is investigated in the present study. It is shown that the contribution of the $\\Sigma(2030)$ hyperon having spin-7/2 and positive parity has a key role to bring the model predictions into a fair agreement with the measured data for the $K^+\\Xi^-$ invariant mass distribution.

  7. Population Studies of Radio and Gamma-Ray Pulsars

    Science.gov (United States)

    Harding, Alice K; Gonthier, Peter; Coltisor, Stefan

    2004-01-01

    Rotation-powered pulsars are one of the most promising candidates for at least some of the 40-50 EGRET unidentified gamma-ray sources that lie near the Galactic plane. Since the end of the EGRO mission, the more sensitive Parkes Multibeam radio survey has detected mere than two dozen new radio pulsars in or near unidentified EGRET sources, many of which are young and energetic. These results raise an important question about the nature of radio quiescence in gamma-ray pulsars: is the non-detection of radio emission a matter of beaming or of sensitivity? The answer is very dependent on the geometry of the radio and gamma-ray beams. We present results of a population synthesis of pulsars in the Galaxy, including for the first time the full geometry of the radio and gamma-ray beams. We use a recent empirically derived model of the radio emission and luminosity, and a gamma-ray emission geometry and luminosity derived theoretically from pair cascades in the polar slot gap. The simulation includes characteristics of eight radio surveys of the Princeton catalog plus the Parkes MB survey. Our results indicate that EGRET was capable of detecting several dozen pulsars as point sources, with the ratio of radio-loud to radio-quiet gamma-ray pulsars increasing significantly to about ten to one when the Parkes Survey is included. Polar cap models thus predict that many of the unidentified EGRET sources could be radio-loud gamma- ray pulsars, previously undetected as radio pulsars due to distance, large dispersion and lack of sensitivity. If true, this would make gamma-ray telescopes a potentially more sensitive tool for detecting distant young neutron stars in the Galactic plane.

  8. MONTE CARLO RADIATION TRANSFER SIMULATIONS OF PHOTOSPHERIC EMISSION IN LONG-DURATION GAMMA-RAY BURSTS

    Energy Technology Data Exchange (ETDEWEB)

    Lazzati, Davide [Department of Physics, Oregon State University, 301 Weniger Hall, Corvallis, OR 97331 (United States)

    2016-10-01

    We present MCRaT, a Monte Carlo Radiation Transfer code for self-consistently computing the light curves and spectra of the photospheric emission from relativistic, unmagnetized jets. We apply MCRaT to a relativistic hydrodynamic simulation of a long-duration gamma-ray burst jet, and present the resulting light curves and time-dependent spectra for observers at various angles from the jet axis. We compare our results to observational results and find that photospheric emission is a viable model to explain the prompt phase of long-duration gamma-ray bursts at the peak frequency and above, but faces challenges when reproducing the flat spectrum below the peak frequency. We finally discuss possible limitations of these results both in terms of the hydrodynamics and the radiation transfer and how these limitations could affect the conclusions that we present.

  9. Concentration Of 228Th, 226Ra, And 40K Radionuclides In Drinking Water In Southern Sumatera

    International Nuclear Information System (INIS)

    Sutarman; Warsono, Asep; Wahyudi

    2000-01-01

    Measurements of 228 Th, 226 Ra, and 40 K concentrations in drinking water on several places in Southern Sumatera (1997-1999) have been carried out. The sample were collected from the Province of Lampung (Kalianda, Bandar Lampung, Kotabumi, Talangpadang, Kotaagung, Liwa, Manggala, and Pakuanratu), and the Province of Southern Sumatera (Palembang-1, Palembang-2, Plaju, Lahat, and Sekayu). Measurements of 228 Th, 226 Ra, and 40 K concentrations in drinking water using the gamma spectrometer with the HP-Ge detector. The results of measurement showed that the concentration was the range of undetectable ( 228 Th concentration, the range of undetectable ( 226 Ra, radionuclide and the range of undetectable (< 128.96 mBq/l) to (880.54 n 22.75) mBq/l with average of (412.12 n 5.02) mBq/l, and the data mentioned above were still far under the maximum permissible concentration. The estimated of annual dose equivalent effective in drinking water was 0.03 mSv/year for public (5 mSv/year)

  10. 40 CFR 180.438 - Lambda-cyhalothrin and an isomer gamma-cyhalothrin; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Lambda-cyhalothrin and an isomer gamma... FOOD Specific Tolerances § 180.438 Lambda-cyhalothrin and an isomer gamma-cyhalothrin; tolerances for residues. (a) General. (1) Tolerances are established for the combined residues of the pyrethroid lambda...

  11. Natural Radioactivity of U-238, Th-232 and K-40 in Surface Soil of Baghdad, Nahrain and Al-Mustansiriyah University in Iraq

    International Nuclear Information System (INIS)

    Ridha, A.A.; Mutter, M.M.; Salim, M.D.

    2015-01-01

    The study of natural radioactivity in public universities soil is very important because of containing a large numbers of students and personnel in small areas and for long periodic times, especially the centers and gathering students areas. So it was chosen the most important universities in Baghdad city according with the students density, which is Baghdad and Nahrain University in Al-Jadriyah region in addition to Al-Mustansiriyah University in Palestine street region. Thirteen soil samples collected from these regions to estimate the radiological impact to the dweller, the concentrations of 238 U, 232 Th and 40 K present in the soil samples were analyzed using HPGe as Gamma-spectrometry. The results showed that the average radioactivity of 238 U is 26.262±4.52 Bq/ kg, for 232 Th is equal to 24.860±4.03 Bq/ kg and for 40 K is 293.706±16.62 Bq/ kg. Thus, the values of specific activity of 238 U, 232 Th and 40 K for all soil samples are in acceptable values of the worldwide average. The maximum value for Ra eq is 119.727±10.94 Bq/ kg recorded in sample (Bag2), with an average value of 76.938±8.44 Bq/ kg. All soil samples have Ra eq value below the 247 Bq/ kg (Iraqi permissibility limit). In addition to radium equivalent, the absorbed gamma dose rate (D), outdoor annual effective dose and hazard indices are calculated in this work and show low values compared with permissible limits. (author)

  12. Lifetime Effective Dose Assessment Based on Background Outdoor Gamma Exposure in Chihuahua City, Mexico

    Directory of Open Access Journals (Sweden)

    Sergio Luevano-Gurrola

    2015-09-01

    Full Text Available Determining ionizing radiation in a geographic area serves to assess its effects on a population’s health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the annual effective dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, the annual effective dose and the lifetime cancer risk, 48 sampling points were randomly selected in Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Müller counter. Outdoor gamma dose rates ranged from 113 to 310 nGy·h−1. At the same sites, 48 soil samples were taken to obtain the activity concentrations of 226Ra, 232Th and 40K and to calculate their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Calculated gamma dose rates ranged from 56 to 193 nGy·h−1. Results indicated that the lifetime effective dose of the inhabitants of Chihuahua City is on average 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of the activity concentrations in soil were 52, 73 and 1097 Bq·kg−1, for 226Ra, 232Th and 40K, respectively. From the analysis, the spatial distribution of 232Th, 226Ra and 40K is to the north, to the north-center and to the south of city, respectively. In conclusion, the natural background gamma dose received by the inhabitants of Chihuahua City is high and mainly due to the geological characteristics of the zone. From the radiological point of view, this kind of study allows us to identify the importance of manmade environments, which are often highly variable and difficult to characterize.

  13. Lifetime Effective Dose Assessment Based on Background Outdoor Gamma Exposure in Chihuahua City, Mexico.

    Science.gov (United States)

    Luevano-Gurrola, Sergio; Perez-Tapia, Angelica; Pinedo-Alvarez, Carmelo; Carrillo-Flores, Jorge; Montero-Cabrera, Maria Elena; Renteria-Villalobos, Marusia

    2015-09-30

    Determining ionizing radiation in a geographic area serves to assess its effects on a population's health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the annual effective dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, the annual effective dose and the lifetime cancer risk, 48 sampling points were randomly selected in Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Müller counter. Outdoor gamma dose rates ranged from 113 to 310 nGy·h(-1). At the same sites, 48 soil samples were taken to obtain the activity concentrations of (226)Ra, (232)Th and (40)K and to calculate their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Calculated gamma dose rates ranged from 56 to 193 nGy·h(-1). Results indicated that the lifetime effective dose of the inhabitants of Chihuahua City is on average 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of the activity concentrations in soil were 52, 73 and 1097 Bq·kg(-1), for (226)Ra, (232)Th and (40)K, respectively. From the analysis, the spatial distribution of (232)Th, (226)Ra and (40)K is to the north, to the north-center and to the south of city, respectively. In conclusion, the natural background gamma dose received by the inhabitants of Chihuahua City is high and mainly due to the geological characteristics of the zone. From the radiological point of view, this kind of study allows us to identify the importance of manmade environments, which are often highly variable and difficult to characterize.

  14. Lifetime Effective Dose Assessment Based on Background Outdoor Gamma Exposure in Chihuahua City, Mexico

    Science.gov (United States)

    Luevano-Gurrola, Sergio; Perez-Tapia, Angelica; Pinedo-Alvarez, Carmelo; Carrillo-Flores, Jorge; Montero-Cabrera, Maria Elena; Renteria-Villalobos, Marusia

    2015-01-01

    Determining ionizing radiation in a geographic area serves to assess its effects on a population’s health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the annual effective dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, the annual effective dose and the lifetime cancer risk, 48 sampling points were randomly selected in Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Müller counter. Outdoor gamma dose rates ranged from 113 to 310 nGy·h−1. At the same sites, 48 soil samples were taken to obtain the activity concentrations of 226Ra, 232Th and 40K and to calculate their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Calculated gamma dose rates ranged from 56 to 193 nGy·h−1. Results indicated that the lifetime effective dose of the inhabitants of Chihuahua City is on average 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of the activity concentrations in soil were 52, 73 and 1097 Bq·kg−1, for 226Ra, 232Th and 40K, respectively. From the analysis, the spatial distribution of 232Th, 226Ra and 40K is to the north, to the north-center and to the south of city, respectively. In conclusion, the natural background gamma dose received by the inhabitants of Chihuahua City is high and mainly due to the geological characteristics of the zone. From the radiological point of view, this kind of study allows us to identify the importance of manmade environments, which are often highly variable and difficult to characterize. PMID:26437425

  15. 226Ra, 232Th and 40K analysis in sand samples from some beaches of Great Vitoria, Espirito Santo, Brazil: preliminary results

    International Nuclear Information System (INIS)

    Aquino, Reginaldo R.; Pecequilo, Brigitte R.S.

    2009-01-01

    The natural radioactivity in superficial beach sand samples of 7 beaches of Great Vitoria, metropolitan region of the State of Espirito Santo, southeast Brazil, was determined from the 226 Ra, 232 Th and 4 0 K contents. The assessed beaches were Manguinhos, Camburi, Praia do Canto, Curva da Jurema, Itapua, Setibao and Areia Preta. Three samples of each beach were sealed in standard 100 mL polyethylene flasks and stored in order to obtain secular equilibrium in the 238 U and 232 Th series. All samples were measured by high resolution gamma spectrometry and the spectra were analyzed with the WinnerGamma software. The 232 Th concentration was determined from the average concentrations of 228 Ac, 212 Pb and 212 Bi and the 226 Ra concentration was determined from the average concentrations of 214 Pb and 214 Bi. Preliminary results show concentrations varying from 9 Bq.kg -1 to 6035 Bq.kg -1 for 232 Th, from 4 Bq.kg -1 to 575 Bq.kg -1 for 226 Ra and from 13 Bq.kg -1 to 142 Bq.kg -1 for 40 K. Areia Preta beach shows the highest values for 232 Th, while the highest value for 226 Ra was observed for Camburi beach. High values of 40 K were observed for Curva da Jurema beach. (author)

  16. An introduction to emission computed tomography

    International Nuclear Information System (INIS)

    Williams, E.D.

    1985-01-01

    This report includes salient features of the theory and an examination of practical considerations for someone who is using or introducing tomography, selecting equipment for it or wishing to develop a clinical application. Emphasis is on gamma camera tomography. The subject is dealt with under the following headings: emission computed and gamma camera tomography and the relationship to other medical imaging techniques, the tomographic reconstruction technique theory, rotating gamma camera tomography, attenuation correction and quantitative reconstruction, other single photon tomographic techniques, positron tomography, image display, clinical application of single photon and positron tomography, and commercial systems for SPECT. Substantial bibliography. (U.K.)

  17. High-energy Neutrino Emission from Short Gamma-Ray Bursts: Prospects for Coincident Detection with Gravitational Waves

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, Shigeo S.; Murase, Kohta; Mészáros, Peter [Department of Physics, Pennsylvania State University, University Park, PA 16802 (United States); Kiuchi, Kenta [Center for Gravitational Physics, Yukawa Institute for Theoretical Physics, Kyoto, Kyoto 606-8502 (Japan)

    2017-10-10

    We investigate current and future prospects for coincident detection of high-energy neutrinos and gravitational waves (GWs). Short gamma-ray bursts (SGRBs) are believed to originate from mergers of compact star binaries involving neutron stars. We estimate high-energy neutrino fluences from prompt emission, extended emission (EE), X-ray flares, and plateau emission, and we show that neutrino signals associated with the EE are the most promising. Assuming that the cosmic-ray loading factor is ∼10 and the Lorentz factor distribution is lognormal, we calculate the probability of neutrino detection from EE by current and future neutrino detectors, and we find that the quasi-simultaneous detection of high-energy neutrinos, gamma-rays, and GWs is possible with future instruments or even with current instruments for nearby SGRBs having EE. We also discuss stacking analyses that will also be useful with future experiments such as IceCube-Gen2.

  18. Long term monitoring of Gamma-Ray emission from the BL Lacertae object (1ES 2200+420)

    Science.gov (United States)

    Gunawardhana, Isuru; VERITAS Collaboration

    2016-03-01

    Blazars are a class of Active Galactic Nuclei (AGN) that have relativistic jets pointing along the observer line of sight. Blazars exhibit variable emission extending from radio to TeV energies. The variability timescale of the TeV flux is a key component of understanding the location of the very high energy emission zones. Deep observations of the quiescent state measurements are also required to disentangle the flaring state emission from quiescent state emission, a prerequisite for understanding the origin of blazar spectral variability. BL Lacertae (also known as 1ES 2200+420), as the namesake for all BL Lac objects, is a prime example of one such blazar. The VERITAS Observatory, an Imaging Atmospheric Cherenkov Telescope (IACT) array sensitive to gamma rays in the range from 85 GeV to 30 TeV, dedicates approximately 110 hours per year on deep observations of known gamma-ray blazars. In this talk, I will describe the TeV photon flux variability of BL Lacertae measured by VERITAS from 2013 to 2015.

  19. Gamma hazards and risk associated with NORM in sediment from amang processing recycling ponds

    International Nuclear Information System (INIS)

    Nasirian Mohesen; Ismail Bahari; Pauzi Abdullah; Azizah JAafar

    2007-01-01

    Amang processing is an important downstream activity of tin mining noted for technologically enhancing naturally occurring radioactive materials. A study was carried out to determine the gamma radiation hazards associated with amang processing with special reference to the sediment accumulated in amang processing ponds. Twenty eight sediment samples from two amang processing plants employing the recycling close water management system were collected and analyzed. The activity concentrations of 226 Ra, 232 Th and 40 K in sediments were measured using gamma spectrometry analysis, with a Hyper Pure Ge-Li detector coupled to a Multi Channel Analyzer detector system. The range of mean activity concentrations of 226 Ra, 232 Th and 40 K were between 40.94 - 189.58 Bq kg -1 , 104.90 - 516.17 Bq kg -1 and 74.8-848.0 Bq/ kg respectively. The maximum activity concentrations of 226 Ra, 232 Th and 40 K recorded were higher than Malaysia average and the worlds natural highest. Gamma Radiation Representative Level Index, I γr associated with these levels of activity concentrations of radionuclide in sediments, warrants an immediate attention from the regulatory authorities. The contribution of amang processing and the use of recycling close water management system in enhancing potential environmental radiological risk are discussed. (author)

  20. Measurement of the CKM matrix angle {gamma} in B{sup {+-}} {yields} D{sup 0} (K{sub S}{pi}{pi}) K{sup *{+-}} using BABAR detector at Slac; Mesure de l'angle {gamma} de la matrice CKM a l'aide des desintegrations B{sup {+-}} {yields} D{sup 0} (K{sub S}{pi}{pi}) K{sup *{+-}} en utilisant le detecteur BABAR a Slac

    Energy Technology Data Exchange (ETDEWEB)

    Pruvot, St

    2007-07-15

    CP violation in the B mesons system has been studied by the B factories for almost 8 years. After a first success with the high precision measurement of the Unitarity Triangle angle {beta}, they are now facing a new challenge: the study of the 2 last angles, {alpha} and {gamma}, which are still poorly known. The work presented in this thesis is related to the measurement of the angle {gamma} using the B{sup -} {yields} D{sup 0}K{sup *-} events from data collected by the BABAR detector at Slac (Stanford linear accelerator). The method is based on the interferences between two amplitudes along the Dalitz plot of the three-body decay D{sup 0} {yields} K{sub S}{pi}{pi}, one related to the V{sub ub} element of the CKM matrix and the other related to the V{sub cb} element. This method has already been used in the measurement of {gamma}in B{sup -} {yields} D{sup 0}K{sup -} and B{sup -} {yields} D{sup *0}K{sup -} decays. Adding the new mode B{sup -} {yields} D{sup 0}K{sup *-} helps improving the statistical error of the measurement by 3 degrees which leads to: {gamma} (67 {+-} 28 {+-} 13 {+-} 11) degrees. The first error is statistical, the second one comes from experimental systematic uncertainties and the third one is the systematic uncertainty associated to the model used to describe the Dalitz plot D{sup 0} {yields} K{sub S}{pi}{pi}. Since this model is a crucial point for the analysis, we describe it in detail. For the future, in order to improve the measurement of {gamma}, it will be necessary to refine the Dalitz model as the number of events available at the B factories will increase. (author)

  1. Internal 40K radiation dose to Indians

    International Nuclear Information System (INIS)

    Ranganathan, S.; Someswara Rao, M.; Nagaratnam, A.; Mishra, U.C.

    2002-01-01

    A group of 350 Indians from both sexes (7-65 years) representing different regions of India was studied for internal 40 K radiation dose from the naturally occurring body 40 K, which was measured in the National Institute of Nutrition (NIN) whole-body counter. Although the 40 K radioactivity reached a peak value by 18 years in female (2,412 Bq) and by 20 years in male (3,058 Bq) and then varied inversely with age in both sexes, the radiation dose did not show such a trend. Boys and girls of 11 years had annual effective dose of nearly 185 mSv, which decreased during adolescence (165 mSv), increased to 175 mSv by 18-20 years in adults and decreased progressively on further ageing to 99 mSv in males and 69 mSv in females at 65 years. The observed annual effective dose (175 mSv) of the young adults was close to that of the ICRP Reference Man (176 mSv) and Indian Reference Man (175 mSv). With a mean specific activity of 55 Bq/kg for the subjects and a conversion coefficient close to 3 mSv per annum per Bq/kg, the average annual effective dose from the internal 40 K turned out to be 165 mSv for Indians. (author)

  2. PROBING THE FLARE ATMOSPHERES OF M DWARFS USING INFRARED EMISSION LINES

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Sarah J.; Kowalski, Adam F.; Hawley, Suzanne L.; Hilton, Eric J.; Wisniewski, John P.; Tofflemire, Benjamin M., E-mail: sjschmidt@astro.washington.edu [Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, National Research Council of Canada (Canada)

    2012-01-20

    We present the results of a campaign to monitor active M dwarfs using infrared spectroscopy, supplemented with optical photometry and spectroscopy. We detected 16 flares during nearly 50 hr of observations on EV Lac, AD Leo, YZ CMi, and VB 8. The three most energetic flares also showed infrared emission, including the first reported detections of P{beta}, P{gamma}, He I {lambda}10830, and Br{gamma} during an M dwarf flare. The strongest flare ({Delta}u = 4.02 on EV Lac) showed emission from H{gamma}, H{delta}, He I {lambda}4471, and Ca II K in the UV/blue and P{beta}, P{gamma}, P{delta}, Br{gamma}, and He I {lambda}10830 in the infrared. The weaker flares ({Delta}u = 1.68 on EV Lac and {Delta}U = 1.38 on YZ CMi) were only observed with photometry and infrared spectroscopy; both showed emission from P{beta}, P{gamma}, and He I {lambda}10830. The strongest infrared emission line, P{beta}, occurred in the active mid-M dwarfs with a duty cycle of {approx}3%-4%. To examine the most energetic flare, we used the static NLTE radiative transfer code RH to produce model spectra based on a suite of one-dimensional model atmospheres. Using a hotter chromosphere than previous one-dimensional atmospheric models, we obtain line ratios that match most of the observed emission lines.

  3. Study of the K{sup {+-}} {yields} {pi}{sup {+-}} {pi}{sup 0} {gamma} decays at the NA48/2 experiment at the CERN SPS

    Energy Technology Data Exchange (ETDEWEB)

    Goy Lopez, S

    2006-12-15

    The NA48/2 experiment has collected a large sample of K{sup {+-}} {yields} {pi}{sup {+-}} {pi}{sup 0} {gamma} decays, providing a unique opportunity of precisely studying this channel. The main results presented here are the relative amounts of direct emission (DE) and interference with respect to the inner Bremsstrahlung component (INT). The methods (maximum likelihood and shape methods) used for extracting the physical results are described. The experimental status is also summarized. The main characteristics of the beam line are explained and the different components of the central detector (the magnetic spectrometer, the electromagnetic calorimeter,...) and the trigger system are described in detail. The event selection of K{sup {+-}} {yields} {pi}{sup {+-}} {pi}{sup 0} {gamma} events is presented and the final number of events used for the extraction of DE and INT components is about 120*10{sup 3} which is more than 5 times larger than that of previous experiments. The Monte-Carlo simulation of NA48 experiment is explained. With the current selection the total background has been estimated to be less than 1% of the expected DE contribution. The results and errors from the maximum likelihood fit for K{sup +} are: Frac(DE) = (4.07 {+-} 0.57) and Frac(INT) = (-2.34 {+-} 1.30) for 75745 events. The corresponding results for K{sup -} are: Frac(DE) = (4.67 {+-} 0.77) and Frac(INT) = (-3.34 {+-} 1.77) for 41932 events. In addition, a CP violating asymmetry in the K{sup +} and K{sup -} branching ratios for this channel has been obtained to be less than 4.5*10{sup -3} at 90% confidence level. (A.C.)

  4. Search for Physics Beyond the Standard Model Using Measurements of CP Violating Asymmetries in Rare B Decays: B0 to K0(S) Pi0 and B0 to K0(S) Pi0 Gamma

    Energy Technology Data Exchange (ETDEWEB)

    Kovalskyi, Dmytro; /Maryland U.

    2006-09-25

    This dissertation presents measurements of time-dependent CP violating asymmetries in the decays B{sup 0} {yields} K{sub s}{sup 0}{pi}{sup 0} and B{sup 0} {yields} K{sub s}{sup 0}{pi}{sup 0}{gamma} based on RUN 1-4 data collected with the BABAR detector at the {Upsilon}(4S) resonance operating at the PEP-II asymmetric e{sup +}e{sup -} collider at SLAC. It was found that the CP violating asymmetry parameters are S{sub K{sub s}{pi}{sup 0}} = 0.35{sub -0.33}{sup +0.30}(stat) {+-} 0.04(syst), C{sub K{sub g}{pi}{sup 0}} = 0.06 {+-} 0.18(stat) {+-} 0.03(syst), S{sub K{sub s}{pi}{sup 0}{gamma}} = 0.9 {+-} 1.0(stat) {+-} 0.2(syst) and C{sub K{sub s}{pi}{sup 0}{gamma}} = -1.0 {+-} 0.5(stat) {+-} 0.2(syst), where B{sup 0} {yields} K{sup +0}{gamma} decays correspond to the K{sub s}{pi}{sup 0} invariant mass interval of [0.8,1.0] GeV and B{sup 0} {yields} K{sub s}{sup 0}{pi}{sup 0}{gamma} of [1.1,1.8] GeV. All results are consistent with the Standard Model predictions.

  5. 40 CFR 60.49Da - Emission monitoring.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Emission monitoring. 60.49Da Section 60... Generating Units for Which Construction is Commenced After September 18, 1978 § 60.49Da Emission monitoring...). (2) As an alternative to the monitoring requirements in paragraph (a)(1) of this section, an owner or...

  6. A re-evaluation of k0 and related nuclear data for the 555.8 keV gamma-line emitted by the 104mRh-104Rh mother-daughter pair for use in NAA

    International Nuclear Information System (INIS)

    Corte, Frans de; Lierde, Stijn van; Simonits, Andras; Bossus, Danieel; Sluijs, Robbert van; Pomme, Stefaan

    1999-01-01

    A re-evaluation is made of the k 0 -factor and related nuclear data for the 555.8 keV gamma-ray of the 104m Rh- 104 Rh mother-daughter pair that are important in neutron activation analysis (NAA). This study considers that the relevant level is also fed by the 4.34 min 104m Rh mother (with an absolute gamma-ray emission probability γ 2 =0.13%) and not only, as assumed in former work, by the 42.3 s 104 Rh daughter isotope (with γ 3 =2.0%). In view of this, generalised equations were developed for both the experimental determination and the analytical use of the k 0 -factor and of the associated parameters k 0 (m)/k 0 (g), Q 0 (m) and Q 0 (g) [(m): 104m Rh; (g): 104 Rh], requiring the introduction of the γ 2 and γ 3 data and also of the 104m Rh→ 104 Rh fractional decay factor F 2 (=0.9987). The experimental determinations were based on irradiations performed in the BR1 reactor in Mol and the WWR-M reactor in Budapest. Furthermore, considering the special formation of the 555.8 keV gamma-ray, the procedure for true-coincidence correction was revised as well. All this led to the compilation and recommendation of a new set of 'k 0 -NAA' data

  7. Determination of natural radioactive elements in Abo Zaabal, Egypt by means of gamma spectroscopy

    International Nuclear Information System (INIS)

    Morsy, Zeinab; Abd El-Wahab, Magda; El-Faramawy, Nabil

    2012-01-01

    Highlights: ► We examined the radioactivity of different type samples from Abo Zaabaal Lake. ► We evaluated the natural nuclide gamma-ray activities and their annual dose rates. ► We evaluated the concentrations of 226 Ra and its hazard indices. ► We assessed the absorbed dose in human. ► All results are within normal ranges. - Abstract: The natural nuclide gamma-ray activities and their respective annual effective dose rates, produced by 238 U, 232 Th, 40 K and 226 Ra, are determined for 10 different natural samples (soil–plant–water) from Abo Zaabaal Lake. This lake is located very close to the Egyptian reactors. The gamma spectra analysis indicates that the photo-gamma lines represent ten radioactive nuclides 234 Th, 239 Pu, 228 Ac, 226 Ra, 212 Pb, 214 Pb, 208 Tl, 212 Bi, 214 Bi and 40 K. These nuclides represent the daughters of the natural radioactive series 238 U and 232 Th with 40 K. The mean activity concentration of 238 U was found to be 6.57, 10.16 and 5.44 Bq kg −1 for (soil–plant–water); 8.46, 8.33 and 6.04 Bq kg −1 of 232 Th, and 136.3, 216.8 and 119.2 Bq kg −1 of 40 K respectively. The mean activity concentrations of 226 Ra were obtained which help to evaluate the radiation hazard indices as radium equivalent, internal and external hazard indices. In addition, to assess the radiation risk to a biosystem, the annual effective dose rate, the absorbed dose in human and the absorbed dose outdoor are also evaluated.

  8. Sterilization of allograft bone: is 25 kGy the gold standard for gamma irradiation?

    Science.gov (United States)

    Nguyen, Huynh; Morgan, David A F; Forwood, Mark R

    2007-01-01

    For several decades, a dose of 25 kGy of gamma irradiation has been recommended for terminal sterilization of medical products, including bone allografts. Practically, the application of a given gamma dose varies from tissue bank to tissue bank. While many banks use 25 kGy, some have adopted a higher dose, while some choose lower doses, and others do not use irradiation for terminal sterilization. A revolution in quality control in the tissue banking industry has occurred in line with development of quality assurance standards. These have resulted in significant reductions in the risk of contamination by microorganisms of final graft products. In light of these developments, there is sufficient rationale to re-establish a new standard dose, sufficient enough to sterilize allograft bone, while minimizing the adverse effects of gamma radiation on tissue properties. Using valid modifications, several authors have applied ISO standards to establish a radiation dose for bone allografts that is specific to systems employed in bone banking. These standards, and their verification, suggest that the actual dose could be significantly reduced from 25 kGy, while maintaining a valid sterility assurance level (SAL) of 10(-6). The current paper reviews the methods that have been used to develop radiation doses for terminal sterilization of medical products, and the current trend for selection of a specific dose for tissue banks.

  9. Car-borne survey of natural background gamma dose rate in Canakkale region (Turkey)

    International Nuclear Information System (INIS)

    Turhan, S.; Arikan, I. H.; Oquz, F.; Aezdemir, T.; Yuecel, B.; Varinlioqlu, A.; Koese, A.

    2012-01-01

    Natural background gamma radiation was measured along roads in the environs of Canakkale region by using a car-borne spectrometer system with a plastic gamma radiation detector. In addition, activity concentrations of 238 U, 226 Ra, 232 Th and 40 K in soil samples from the Canakkale region were determined by using a gamma spectrometer with an HPGe detector. A total of 92 856 data of the background gamma dose rate were collected for the Canakkale region. The background gamma dose rate of the Canakkale region was mapped using ArcGIS software, applying the geostatistical inverse distance-weighted method. The average and population-weighted average of the gamma dose are 55.4 and 40.6 nGy h -1 , respectively. The corresponding average annual effective dose to the public ranged from 26.6 to 96.8 μSv. (authors)

  10. HNF-1B specifically regulates the transcription of the {gamma}a-subunit of the Na{sup +}/K{sup +}-ATPase

    Energy Technology Data Exchange (ETDEWEB)

    Ferre, Silvia [Department of Physiology, Radboud University Nijmegen Medical Centre (Netherlands); Veenstra, Gert Jan C. [Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen (Netherlands); Bouwmeester, Rianne; Hoenderop, Joost G.J. [Department of Physiology, Radboud University Nijmegen Medical Centre (Netherlands); Bindels, Rene J.M., E-mail: r.bindels@fysiol.umcn.nl [Department of Physiology, Radboud University Nijmegen Medical Centre (Netherlands)

    2011-01-07

    Research highlights: {yields} Defects in HNF-1B transcription factor affect Mg{sup 2+} handling in the distal kidney. {yields} {gamma}a- and {gamma}b- subunits of the Na{sup +}/K{sup +}-ATPase colocalize in the distal convoluted tubule of the nephron. {yields} HNF-1B specifically activates {gamma}a expression. {yields} HNF-1B mutants have a dominant negative effect on wild type HNF-1B activity. {yields} Defective transcription of {gamma}a may promote renal Mg{sup 2+} wasting. -- Abstract: Hepatocyte nuclear factor-1B (HNF-1B) is a transcription factor involved in embryonic development and tissue-specific gene expression in several organs, including the kidney. Recently heterozygous mutations in the HNF1B gene have been identified in patients with hypomagnesemia due to renal Mg{sup 2+} wasting. Interestingly, ChIP-chip data revealed HNF-1B binding sites in the FXYD2 gene, encoding the {gamma}-subunit of the Na{sup +}/K{sup +}-ATPase. The {gamma}-subunit has been described as one of the molecular players in the renal Mg{sup 2+} reabsorption in the distal convoluted tubule (DCT). Of note, the FXYD2 gene can be alternatively transcribed into two main variants, namely {gamma}a and {gamma}b. In the present study, we demonstrated via two different reporter gene assays that HNF-1B specifically acts as an activator of the {gamma}a-subunit, whereas the {gamma}b-subunit expression was not affected. Moreover, the HNF-1B mutations H69fsdelAC, H324S325fsdelCA, Y352finsA and K156E, previously identified in patients with hypomagnesemia, prevented transcription activation of {gamma}a-subunit via a dominant negative effect on wild type HNF1-B. By immunohistochemistry, it was shown that the {gamma}a- and {gamma}b-subunits colocalize at the basolateral membrane of the DCT segment of mouse kidney. On the basis of these data, we suggest that abnormalities involving the HNF-1B gene may impair the relative abundance of {gamma}a and {gamma}b, thus affecting the transcellular Mg{sup 2

  11. A Temporal Correlation in Quiescent Gamma-Ray Burst Prompt Emission: Evidence for Prognitor Memory

    Science.gov (United States)

    Patton, Thomas L.; Giblin, Timothy; Hakkila, Jon E.

    2018-06-01

    In spite of the insight gained into the nature of the Gamma-Ray Bursts (GRB) from early and late-time X-Ray observations in the Swift era, GRB prompt emission continues to provide clues and new insight into the activity of the central engine. A comprehensive understanding of all emission components observed in GRBs, from the traditional prompt GRB emission to the long lived X-Ray and optical decay super- imposed with late-time flaring activity, currently remains allusive. Using data from the Swift Burst Alert Telescope (BAT), we've identified and measured durations observed in GRBs that exhibit multi-episodic prompt emission behavior. Duration analysis of the burst attributes revealed no significant correlations between emissions and quiet time durations. This variability allows us to extrapolate that the central engine is constantly active.

  12. Current Sheets in Pulsar Magnetospheres and Winds: Particle Acceleration and Pulsed Gamma Ray Emission

    Science.gov (United States)

    Arons, Jonathan

    The research proposed addresses understanding of the origin of non-thermal energy in the Universe, a subject beginning with the discovery of Cosmic Rays and continues, including the study of relativistic compact objects - neutron stars and black holes. Observed Rotation Powered Pulsars (RPPs) have rotational energy loss implying they have TeraGauss magnetic fields and electric potentials as large as 40 PetaVolts. The rotational energy lost is reprocessed into particles which manifest themselves in high energy gamma ray photon emission (GeV to TeV). Observations of pulsars from the FERMI Gamma Ray Observatory, launched into orbit in 2008, have revealed 130 of these stars (and still counting), thus demonstrating the presence of efficient cosmic accelerators within the strongly magnetized regions surrounding the rotating neutron stars. Understanding the physics of these and other Cosmic Accelerators is a major goal of astrophysical research. A new model for particle acceleration in the current sheets separating the closed and open field line regions of pulsars' magnetospheres, and separating regions of opposite magnetization in the relativistic winds emerging from those magnetopsheres, will be developed. The currents established in recent global models of the magnetosphere will be used as input to a magnetic field aligned acceleration model that takes account of the current carrying particles' inertia, generalizing models of the terrestrial aurora to the relativistic regime. The results will be applied to the spectacular new results from the FERMI gamma ray observatory on gamma ray pulsars, to probe the physics of the generation of the relativistic wind that carries rotational energy away from the compact stars, illuminating the whole problem of how compact objects can energize their surroundings. The work to be performed if this proposal is funded involves extending and developing concepts from plasma physics on dissipation of magnetic energy in thin sheets of

  13. Supersymmetric corrections to the K/sub L/ -> 2. gamma. process

    Energy Technology Data Exchange (ETDEWEB)

    Abad, J.; Rodriguez-Trias, R.

    1988-11-01

    An improved calculation of susy-corrections to the K/sub L/ -> 2..gamma.. process is done, including also the charged-Higgs contributions. The Higgsino-Wino mixings are carefully considered and the results are presented as a function of a susy-breaking parameter. An evaluation of the diagrams which include super-symmetric penguins is also done, finding a contribution somewhat lower than the previous one. We conclude that the Higgs and susy amplitudes are smaller than the standard amplitude.

  14. A measurement of $K^{\\pm} \\to \\pi^{\\pm} \\gamma \\gamma$ decay with the NA48 Detector

    CERN Document Server

    Morales, Cristina

    The goal of this thesis was an experimental test of an eective theory of strong interactions at low energy, called Chiral Perturbation Theory (ChPT). Weak decays of kaon mesons provide such a test. In particular, K ! decays are interesting because there is no tree-level O(p2) contribution in ChPT, and the leading contributions start at O(p4). At this order, these decays include one undetermined coupling constant, ^c. Both the branching ratio and the spectrum shape of K ! decays are sensitive to this parameter. O(p6) contributions to K ! ChPT predict a 30-40% increase in the branching ratio. From the measurement of the branching ratio and spectrum shape of K ! decays, it is possible to determine a model dependent value of ^c and also to examine whether the O(p6) corrections are necessary and enough to explain the rate. About 40% of the data collected in the year 2003 by the NA48/2 experiment have been analyzed and 908 K ! candidates with about 8% background contamination have been selected in th...

  15. Search for solar axion emission from $^7$Li and D(p,$\\gamma)^3$He nuclear decays with the CAST $\\gamma$-ray calorimeter

    CERN Document Server

    Andriamonje, S.; Autiero, D.; Barth, K.; Belov, A.; Beltran, B.; Brauninger, H.; Carmona, J.M.; Cebrian, S.; Collar, J.I.; Dafni, T.; Davenport, M.; Di Lella, L.; Eleftheriadis, C.; Englhauser, J.; Fanourakis, G.; Ferrer-Ribas, E.; Fischer, H.; Franz, J.; Friedrich, P.; Geralis, T.; Giomataris, I.; Gninenko, S.; Gomez, H.; Hasinoff, M.; Heinsius, F.H.; Hoffmann, D.H.H.; Irastorza, I.G.; Jacoby, J.; Jakovcic, K.; Kang, D.; Konigsmann, K.; Kotthaus, R.; Krcmar, M.; Kousouris, K.; Kuster, M.; Lakic, B.; Lasseur, C.; Liolios, A.; Ljubicic, A.; Lutz, G.; Luzon, G.; Miller, D.W.; Morales, J.; Ortiz, A.; Papaevangelou, T.; Placci, A.; Raffelt, G.; Riege, H.; Rodriguez, A.; Ruz, J.; Savvidis, I.; Semertzidis, Y.; Serpico, P.; Stewart, L.; Vieira, J.D.; Villar, J.; Vogel, J.; Walckiers, L.; Zioutas, K.

    2010-01-01

    We present the results of a search for a high-energy axion emission signal from 7Li (0.478 MeV) and D(p,gamma)3He (5.5 MeV) nuclear transitions using a low-background gamma-ray calorimeter during Phase I of the CAST experiment. These so-called "hadronic axions" could provide a solution to the long-standing strong-CP problem and can be emitted from the solar core from nuclear M1 transitions. This is the first such search for high-energy pseudoscalar bosons with couplings to nucleons conducted using a helioscope approach. No excess signal above background was found.

  16. Effect of gamma irradiation at doses of 5-15 kGy on the quality properties of durum wheat semolina

    International Nuclear Information System (INIS)

    Taha, S.A.

    1990-01-01

    Semolina purified from four durum wheat varieties were gamma-irradiated with doses of 0, 5, 10 and 15 kGy, i.e., dose levels expected to improve the colour of pasta products, suitable for reduction of microbial contamination, and high doses required for insect disinfestation. The irradiation resulted in significant losses in carotenoid content and oxidative enzyme activities. Gamma irradiation slightly affected the mixing properties, greatly reduced the gluten strength and adversely affected firmness of cooked pasta. Consequently, preservative gamma irradiation of durum wheat semolina should be limited to a maximum dose of 5 kGy. (author) 39 refs.; 3 tabs

  17. Assessment of environmental (226)Ra, (232)Th and (40)K concentrations in the region of elevated radiation background in Segamat District, Johor, Malaysia.

    Science.gov (United States)

    Saleh, Muneer Aziz; Ramli, Ahmad Termizi; Alajerami, Yasser; Aliyu, Abubakar Sadiq

    2013-10-01

    Extensive environmental survey and measurements of gamma radioactivity in the soil samples collected from Segamat District were conducted. Two gamma detectors were used for the measurements of background radiation in the area and the results were used in the computation of the mean external radiation dose rate and mean weighted dose rate, which are 276 nGy h(-1) and 1.169 mSv y(-1), respectively. A high purity germanium (HPGe) detector was used in the assessment of activity concentrations of (232)Th, (226)Ra and (40)K. The results of the gamma spectrometry range from 11 ± 1 to 1210 ± 41 Bq kg(-1) for (232)Th, 12 ± 1 to 968 ± 27 Bq kg(-1) for (226)Ra, and 12 ± 2 to 2450 ± 86 Bq kg(-1) for (40)K. Gross alpha and gross beta activity concentrations range from 170 ± 50 to 4360 ± 170 Bq kg(-1) and 70 ± 20 to 4690 ± 90 Bq kg(-1), respectively. These results were used in the plotting of digital maps (using ARCGIS 9.3) for isodose. The results are compared with values giving in UNSCEAR 2000. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Gamma-ray and neutrino diffuse emissions of the Galaxy above the TeV

    CERN Document Server

    Gaggero, Daniele; Marinelli, Antonio; Urbano, Alfredo; Valli, Mauro

    2016-01-01

    As recently shown, Fermi-LAT measurements of the diffuse gamma-ray emission from the Galaxy favor the presence of a smooth softening in the primary cosmic-ray spectrum with increasing Galactocentric distance. This result can be interpreted in terms of a spatial-dependent rigidity scaling of the diffusion coefficient. The DRAGON code was used to build a model based on such feature. That scenario correctly reproduces the latest Fermi-LAT results as well as local cosmic-ray measurements from PAMELA, AMS-02 and CREAM. Here we show that the model, if extrapolated at larger energies, grasps both the gamma-ray flux measured by MILAGRO at 15 TeV and the H.E.S.S. data from the Galactic ridge, assuming that the cosmic-ray spectral hardening found by those experiments at about 250 GeV/n is present in the whole inner Galactic plane region. Moreover, we show as that model also predicts a neutrino emission which may account for a significant fraction, as well as for the correct spectral shape, of the astrophysical flux mea...

  19. 40 CFR 86.1724-01 - Emission data vehicle selection.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Emission data vehicle selection. 86... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Provisions for the Voluntary National Low Emission Vehicle Program for Light-Duty Vehicles and...

  20. Natural gamma radioactivity and of {sup 137} Cs in soil of the Chimaltitan municipality, Jalisco, Mexico; Radiactividad gamma natural y del {sup 137} Cs en suelo del Municipio de Chimaltitan, Jalisco, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Garay, A.; Mireles, F.; Quirino, L.L.; Davila, J.I.; Rios, C.; Lugo, J.F.; Soriano, J.M.; Angoli, A. [UAEN-Universidad Autonoma de Zacatecas, Cipres 10, Frac. La Penuela, 98000 Zacatecas (Mexico)]. e-mail: albinogaray@hotmail.com.mx

    2003-07-01

    With the purpose of determining the activity due to the natural presence of the {sup 226} Ra, {sup 232} Th, {sup 40} K and {sup 137} Cs in soil samples, of the municipality of Chimaltitan Jalisco. A set of these samples was measured in a gamma ray spectrometric system based on a High-purity Germanium detector. It is well-known that approximately 87% of the dose of the received radiation by the population is due to sources of natural radiation and 13% of the anthropogenic radiation. The gamma radiation comes mainly from the {sup 40} K and of those radionuclides of the series of radioactive decay of {sup 238} U and {sup 232} Th that its find dispersed thoroughly in the terrestrial crust. In this work its were analyzed twenty-two soil samples. It is enlarged the activity characterization for the radioisotopes of {sup 226} Ra {sup 232} Th, {sup 40} K and {sup 137} Cs. (Author)

  1. Natural gamma radioactivity and of 137 Cs in soil of the Chimaltitan municipality, Jalisco, Mexico

    International Nuclear Information System (INIS)

    Garay, A.; Mireles, F.; Quirino, L.L.; Davila, J.I.; Rios, C.; Lugo, J.F.; Soriano, J.M.; Angoli, A.

    2003-01-01

    With the purpose of determining the activity due to the natural presence of the 226 Ra, 232 Th, 40 K and 137 Cs in soil samples, of the municipality of Chimaltitan Jalisco. A set of these samples was measured in a gamma ray spectrometric system based on a High-purity Germanium detector. It is well-known that approximately 87% of the dose of the received radiation by the population is due to sources of natural radiation and 13% of the anthropogenic radiation. The gamma radiation comes mainly from the 40 K and of those radionuclides of the series of radioactive decay of 238 U and 232 Th that its find dispersed thoroughly in the terrestrial crust. In this work its were analyzed twenty-two soil samples. It is enlarged the activity characterization for the radioisotopes of 226 Ra 232 Th, 40 K and 137 Cs. (Author)

  2. Study of associated gamma from niobium under 14. 9 MeV neutron bombardments

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Hongyu; Yan Yiming; Fan Guoying; Lan Liqiac; Sun Suxu; Wang Qi; Hua Ming; Han Chongzhen; Liu Shuzhenn; Rong Yaning; and others

    1989-02-01

    The gamma ray spectra from niobium under 14.9 MeV neutron bombardments were measured by means of a pulsed /ital T/(/ital d/, /ital n/)/sup 4/He neutron source, associated particle method, Ge(Li) detector and time-of-flight technique at 7 angles between 30/degree/ and 140/degree/. 79 gamma lines were determined by a high resolution gamma spectrum analysis program, and reaction types and transition levels of 62 lines were roughly assigned. There were 40 ones of 79 lines, which were first found in reactions induced by neutrons. The differential cross sections of every gamma line at 7 angles were determined. It is shown that associated gamma ray emissions from this reaction are basically isotropic.

  3. A re-evaluation of k sub 0 and related nuclear data for the 555.8 keV gamma-line emitted by the sup 1 sup 0 sup 4 sup m Rh- sup 1 sup 0 sup 4 Rh mother-daughter pair for use in NAA

    CERN Document Server

    Corte, F D; Simonits, A; Bossus, D; Sluijs, R V; Pommé, S

    1999-01-01

    A re-evaluation is made of the k sub 0 -factor and related nuclear data for the 555.8 keV gamma-ray of the sup 1 sup 0 sup 4 sup m Rh- sup 1 sup 0 sup 4 Rh mother-daughter pair that are important in neutron activation analysis (NAA). This study considers that the relevant level is also fed by the 4.34 min sup 1 sup 0 sup 4 sup m Rh mother (with an absolute gamma-ray emission probability gamma sub 2 =0.13%) and not only, as assumed in former work, by the 42.3 s sup 1 sup 0 sup 4 Rh daughter isotope (with gamma sub 3 =2.0%). In view of this, generalised equations were developed for both the experimental determination and the analytical use of the k sub 0 -factor and of the associated parameters k sub 0 (m)/k sub 0 (g), Q sub 0 (m) and Q sub 0 (g) [(m): sup 1 sup 0 sup 4 sup m Rh; (g): sup 1 sup 0 sup 4 Rh], requiring the introduction of the gamma sub 2 and gamma sub 3 data and also of the sup 1 sup 0 sup 4 sup m Rh-> sup 1 sup 0 sup 4 Rh fractional decay factor F sub 2 (=0.9987). The experimental determinations...

  4. 40 CFR 86.435-78 - Extrapolated emission values.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Extrapolated emission values. 86.435-78 Section 86.435-78 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Regulations for 1978 and Later New Motorcycles, General Provisions § 86.435-78 Extrapolated emission values...

  5. Search for the Theta+ pentaquark in the gamma d -> Lambda n K+ reaction measured with CLAS

    Energy Technology Data Exchange (ETDEWEB)

    Silvia Niccolai; Marco Mirazita; Patrizia Rossi; Nathan Baltzell; Daniel Carman; Kenneth Hicks; Bryan McKinnon; Tsutomu Mibe; Stepan Stepanyan; David Tedeschi; Gary Adams; Pawel Ambrozewicz; Sergio Pereira; Marco Anghinolfi; Gegham Asryan; Harutyun AVAKIAN; H. Bagdasaryan; Nathan Baillie; Jacques Ball; V. Batourine; Marco Battaglieri; Ivan Bedlinski; Ivan Bedlinskiy; Ivan Bedlinski; Ivan Bedlinskiy; Mehmet Bektasoglu; Matthew Bellis; Nawal Benmouna; Barry Berman; Angela Biselli; Sergey Boyarinov; Sylvain Bouchigny; Robert Bradford; Derek Branford; William Briscoe; William Brooks; Stephen Bueltmann; Volker Burkert; Cornel Butuceanu; John Calarco; S.L. Careccia; Bryan Carnahan; Shifeng Chen; Philip Cole; Patrick Collins; Philip Coltharp; Donald Crabb; Hall Crannell; V. Crede; John Cummings; Natalya Dashyan; Pavel Degtiarenko; Rita De Masi; Airton Deppman; Enzo De Sanctis; Alexandre Deur; Raffaella De Vita; Kahanawita Dharmawardane; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; Michael Dugger; Oleksandr Dzyubak; Hovanes Egiyan; Kim Egiyan; L. El Fassi; Latifa Elouadrhiri; Paul Eugenio; Gleb Fedotov; Gerald Feldman; Herbert Funsten; Michel Garcon; Gagik Gavalian; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; John Goetz; Atilla Gonenc; Christopher Gordon; Ralf Gothe; Keith Griffioen; Michel Guidal; Nevzat Guler; Lei Guo; Vardan Gyurjyan; Cynthia Hadjidakis; Kawtar Hafidi; Hayk Hakobyan; Rafael Hakobyan; John Hardie; F. Hersman; Ishaq Hleiqawi; Maurik Holtrop; Charles Hyde-Wright; Yordanka Ilieva; David Ireland; Boris Ishkhanov; Eugeny Isupov; Mark Ito; David Jenkins; Hyon-Suk Jo; Kyungseon Joo; Henry Juengst; James Kellie; Mahbubul Khandaker; Wooyoung Kim; Andreas Klein; Franz Klein; Alexei Klimenko; Mikhail Kossov; Laird Kramer; V. Kubarovsky; Joachim Kuhn; Sebastian Kuhn; Sergey Kuleshov; Jeff Lachniet; Jorn Langheinrich; David Lawrence; Tsung-shung Lee; Kenneth Livingston; H. Lu; Marion MacCormick; Nikolai Markov; Bernhard Mecking; Jonathan Mellor; Joseph Melone; Mac Mestayer; Curtis Meyer; Konstantin Mikhaylov; Ralph Minehart; Rory Miskimen; Viktor Mokeev; Ludyvine Morand; Steven Morrow; Maryam Moteabbed; Gordon Mutchler; Pawel Nadel-Turonski; James Napolitano; Rakhsha Nasseripour; Gabriel Niculescu; Maria-Ioana Niculescu; Bogdan Niczyporuk; Megh Niroula; Rustam Niyazov; Mina Nozar; Jorge De Olivei Echeimberg; Mikhail Osipenko; Alexander Ostrovidov; K. Park; Evgueni Pasyuk; Craig Paterson; Joshua Pierce; Nikolay Pivnyuk; Dinko Pocanic; Oleg Pogorelko; Sergey Pozdnyakov; Barry Preedom; John Price; Yelena Prok; Dan Protopopescu; Brian Raue; Gregory Riccardi; Giovanni Ricco; Marco Ripani; Barry Ritchie; Federico Ronchetti; Guenther Rosner; Franck Sabatie; Carlos Salgado; Joseph Santoro; Vladimir Sapunenko; Reinhard Schumacher; Vladimir Serov; Youri Sharabian; Nikolay Shvedunov; Elton Smith; Lee Smith; Daniel Sober; Aleksey Stavinskiy; Stepan Stepanyan; Burnham Stokes; Paul Stoler; Igor Strakovski; Steffen Strauch; Mauro Taiuti; Ulrike Thoma; Avtandil Tkabladze; Svyatoslav Tkachenko; Luminita Todor; Clarisse Tur; Maurizio Ungaro; Michael Vineyard; Alexander Vlassov; Daniel Watts; Lawrence Weinstein; Dennis Weygand; M. Williams; Elliott Wolin; Michael Wood; Amrit Yegneswaran; Lorenzo Zana; Jixie Zhang; Bo Zhao; Zhiwen Zhao

    2006-04-26

    For the first time, the reaction gamma d -> Lambda n K+ has been analyzed in order to search for the exotic pentaquark baryon Theta+(1540). The data were taken at Jefferson Lab, using the Hall-B tagged-photon beam of energy between 0.8 and 3.6 GeV and the CEBAF Large Acceptance Spectrometer (CLAS). No statistically significant structures were observed in the nK+ invariant mass distribution. The upper limit on the gamma d -> Lambda Theta+ integrated cross section has been calculated and found to be between 5 and 25 nb, depending on the production model assumed. The upper limit on the differential cross section is also reported.

  6. Search for the Theta+ pentaquark in the gamma d -> Lambda n K+ reaction measured with CLAS

    International Nuclear Information System (INIS)

    Silvia Niccolai; Marco Mirazita; Patrizia Rossi; Nathan Baltzell; Daniel Carman; Kenneth Hicks; Bryan McKinnon; Tsutomu Mibe; Stepan Stepanyan; David Tedeschi; Gary Adams; Pawel Ambrozewicz; Sergio Pereira; Marco Anghinolfi; Gegham Asryan; Harutyun AVAKIAN; H. Bagdasaryan; Nathan Baillie; Jacques Ball; V. Batourine; Marco Battaglieri; Ivan Bedlinski; Ivan Bedlinskiy; Ivan Bedlinski; Ivan Bedlinskiy; Mehmet Bektasoglu; Matthew Bellis; Nawal Benmouna; Barry Berman; Angela Biselli; Sergey Boyarinov; Sylvain Bouchigny; Robert Bradford; Derek Branford; William Briscoe; William Brooks; Stephen Bueltmann; Volker Burkert; Cornel Butuceanu; John Calarco; S.L. Careccia; Bryan Carnahan; Shifeng Chen; Philip Cole; Patrick Collins; Philip Coltharp; Donald Crabb; Hall Crannell; V. Crede; John Cummings; Natalya Dashyan; Pavel Degtiarenko; Rita De Masi; Airton Deppman; Enzo De Sanctis; Alexandre Deur; Raffaella De Vita; Kahanawita Dharmawardane; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; Michael Dugger; Oleksandr Dzyubak; Hovanes Egiyan; Kim Egiyan; L. El Fassi; Latifa Elouadrhiri; Paul Eugenio; Gleb Fedotov; Gerald Feldman; Herbert Funsten; Michel Garcon; Gagik Gavalian; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; John Goetz; Atilla Gonenc; Christopher Gordon; Ralf Gothe; Keith Griffioen; Michel Guidal; Nevzat Guler; Lei Guo; Vardan Gyurjyan; Cynthia Hadjidakis; Kawtar Hafidi; Hayk Hakobyan; Rafael Hakobyan; John Hardie; F. Hersman; Ishaq Hleiqawi; Maurik Holtrop; Charles Hyde-Wright; Yordanka Ilieva; David Ireland; Boris Ishkhanov; Eugeny Isupov; Mark Ito; David Jenkins; Hyon-Suk Jo; Kyungseon Joo; Henry Juengst; James Kellie; Mahbubul Khandaker; Wooyoung Kim; Andreas Klein; Franz Klein; Alexei Klimenko; Mikhail Kossov; Laird Kramer; V. Kubarovsky; Joachim Kuhn; Sebastian Kuhn; Sergey Kuleshov; Jeff Lachniet; Jorn Langheinrich; David Lawrence; Tsung-shung Lee; Kenneth Livingston; H. Lu; Marion MacCormick; Nikolai Markov; Bernhard Mecking

    2006-01-01

    For the first time, the reaction gamma d -> Lambda n K+ has been analyzed in order to search for the exotic pentaquark baryon Theta+(1540). The data were taken at Jefferson Lab, using the Hall-B tagged-photon beam of energy between 0.8 and 3.6 GeV and the CEBAF Large Acceptance Spectrometer (CLAS). No statistically significant structures were observed in the nK+ invariant mass distribution. The upper limit on the gamma d -> Lambda Theta+ integrated cross section has been calculated and found to be between 5 and 25 nb, depending on the production model assumed. The upper limit on the differential cross section is also reported

  7. Calibration of thermometers in the range from 4K to 40K

    International Nuclear Information System (INIS)

    Cruz, M.E. de la; Sereni, Julian; Salva, Horacio.

    1977-06-01

    Carbon and Germanium resistors have been calibrated against a standard in the temperature range from 4K to 40K. From the data, values of temperature are obtained with 0,1% error (std deviation). These calibrations have been also checked against specific heat measurements. (author) [es

  8. Observation of gamma-ray bursts with GINGA

    International Nuclear Information System (INIS)

    Murakami, Toshio; Fujii, Masami; Nishimura, Jun

    1989-01-01

    Gamma-ray Burst Detector System (GBD) on board the scientific satellite 'GINGA' which was launched on Feb. 5, 1987, was realized as an international cooperation between ISAS and LANL. It has recorded more than 40 Gamma-Ray Burst candidates during 20 months observation. Although many observational evidences were accumulated in past 20 years after the discovery of gamma-ray burst by LANL scientists, there are not enough evidence to determine the origin and the production mechanism of the gamma-ray burst. GBD consists of a proportional counter and a NaI scintillation counter so that it became possible to observe energy spectrum of the gamma-ray burst with high energy resolution over wide range of energy (1.5-380 keV) together with high time resolution. As the result of observation, the following facts are obtained: (1) A large fraction of observed gamma-ray bursts has a long X-ray tail after the harder part of gamma-ray emission has terminated. (2) Clear spectral absorption features with harmonic in energy was observed in some of the energy spectrum of gamma-ray bursts. These evidences support the hypothesis that the strongly magnetized neutron star is the origin of gamma-ray burst. (author)

  9. GAMMA-RAY BURST REVERSE SHOCK EMISSION IN EARLY RADIO AFTERGLOWS

    Energy Technology Data Exchange (ETDEWEB)

    Resmi, Lekshmi [Indian Institute of Space Science and Technology, Trivandrum (India); Zhang, Bing, E-mail: l.resmi@iist.ac.in [Department of Physics and Astronomy, University of Nevada, Las Vegas (United States)

    2016-07-01

    Reverse shock (RS) emission from gamma-ray bursts is an important tool in investigating the nature of the ejecta from the central engine. If the magnetization of the ejecta is not high enough to suppress the RS, a strong RS emission component, usually peaking in the optical/IR band early on, would provide an important contribution to early afterglow light curve. In the radio band, synchrotron self-absorption may suppress early RS emission and also delay the RS peak time. In this paper, we calculate the self-absorbed RS emission in the radio band under different dynamical conditions. In particular, we stress that the RS radio emission is subject to self-absorption in both RSs and forward shocks (FSs). We calculate the ratio between the RS to FS flux at the RS peak time for different frequencies, which is a measure of the detectability of the RS emission component. We then constrain the range of physical parameters for a detectable RS, in particular the role of magnetization. We notice that unlike optical RS emission which is enhanced by moderate magnetization, moderately magnetized ejecta do not necessarily produce a brighter radio RS due to the self-absorption effect. For typical parameters, the RS emission component would not be detectable below 1 GHz unless the medium density is very low (e.g., n < 10{sup −3} cm{sup −3} for the interstellar medium and A {sub *} < 5 × 10{sup −4} for wind). These predictions can be tested using the afterglow observations from current and upcoming radio facilities such as the Karl G. Jansky Very Large Array, the Low-Frequency Array, the Five Hundred Meter Aperture Spherical Telescope, and the Square Kilometer Array.

  10. The distribution and abundance of gamma emitting radionuclides in Lake Ontario sediments

    International Nuclear Information System (INIS)

    McKinley, R.S.

    1985-03-01

    The distribution of gamma emitting radionuclides in Lake Ontario sediments was investigated. Samples were collected using a systematic design in the vicinity of Pickering and Darlington, and supplemented by lakewide offshore samples. Naturally occurring 40 K was the predominant source of gamma activity. 60 Co was the only potentially CANDU released radionuclide which showed a distributional association with the Pickering 'A' NGS discharge

  11. SEARCH FOR VERY HIGH ENERGY GAMMA-RAY EMISSION FROM PULSAR-PULSAR WIND NEBULA SYSTEMS WITH THE MAGIC TELESCOPE

    International Nuclear Information System (INIS)

    Anderhub, H.; Biland, A.; Antonelli, L. A.; Antoranz, P.; Balestra, S.; Barrio, J. A.; Bose, D.; Backes, M.; Becker, J. K.; Baixeras, C.; Bastieri, D.; Bock, R. K.; Gonzalez, J. Becerra; Bednarek, W.; Berger, K.; Bernardini, E.; Bonnoli, G.; Bordas, P.; Bosch-Ramon, V.; Tridon, D. Borla

    2010-01-01

    The MAGIC collaboration has searched for high-energy gamma-ray emission of some of the most promising pulsar candidates above an energy threshold of 50 GeV, an energy not reachable up to now by other ground-based instruments. Neither pulsed nor steady gamma-ray emission has been observed at energies of 100 GeV from the classical radio pulsars PSR J0205+6449 and PSR J2229+6114 (and their nebulae 3C58 and Boomerang, respectively) and the millisecond pulsar PSR J0218+4232. Here, we present the flux upper limits for these sources and discuss their implications in the context of current model predictions.

  12. SkyFACT: high-dimensional modeling of gamma-ray emission with adaptive templates and penalized likelihoods

    Energy Technology Data Exchange (ETDEWEB)

    Storm, Emma; Weniger, Christoph [GRAPPA, Institute of Physics, University of Amsterdam, Science Park 904, 1090 GL Amsterdam (Netherlands); Calore, Francesca, E-mail: e.m.storm@uva.nl, E-mail: c.weniger@uva.nl, E-mail: francesca.calore@lapth.cnrs.fr [LAPTh, CNRS, 9 Chemin de Bellevue, BP-110, Annecy-le-Vieux, 74941, Annecy Cedex (France)

    2017-08-01

    We present SkyFACT (Sky Factorization with Adaptive Constrained Templates), a new approach for studying, modeling and decomposing diffuse gamma-ray emission. Like most previous analyses, the approach relies on predictions from cosmic-ray propagation codes like GALPROP and DRAGON. However, in contrast to previous approaches, we account for the fact that models are not perfect and allow for a very large number (∼> 10{sup 5}) of nuisance parameters to parameterize these imperfections. We combine methods of image reconstruction and adaptive spatio-spectral template regression in one coherent hybrid approach. To this end, we use penalized Poisson likelihood regression, with regularization functions that are motivated by the maximum entropy method. We introduce methods to efficiently handle the high dimensionality of the convex optimization problem as well as the associated semi-sparse covariance matrix, using the L-BFGS-B algorithm and Cholesky factorization. We test the method both on synthetic data as well as on gamma-ray emission from the inner Galaxy, |ℓ|<90{sup o} and | b |<20{sup o}, as observed by the Fermi Large Area Telescope. We finally define a simple reference model that removes most of the residual emission from the inner Galaxy, based on conventional diffuse emission components as well as components for the Fermi bubbles, the Fermi Galactic center excess, and extended sources along the Galactic disk. Variants of this reference model can serve as basis for future studies of diffuse emission in and outside the Galactic disk.

  13. Search for time modulations in the decay constant of 40K and 226Ra at the underground Gran Sasso Laboratory

    Science.gov (United States)

    Bellotti, E.; Broggini, C.; Di Carlo, G.; Laubenstein, M.; Menegazzo, R.

    2018-05-01

    Time modulations at per mil level have been reported to take place in the decay constant of several nuclei with period of one year (most cases) but also of about one month or one day. On the other hand, experiments with similar or better sensitivity have been unable to detect any modulation. In this letter we give the results of the activity study of two different sources: 40K and 226Ra. The two gamma spectrometry experiments have been performed underground at the Gran Sasso Laboratory, this way suppressing the time dependent cosmic ray background. Briefly, our measurements reached the sensitivity of 3.4 and 3.5 parts over 106 for 40K and 226Ra, respectively (1 sigma) and they do not show any statistically significant evidence of time dependence in the decay constant. We also give the results of the activity measurement at the time of the two strong X-class solar flares which took place in September 2017. Our data do not show any unexpected time dependence in the decay rate of 40K in correspondence with the two flares. To the best of our knowledge, these are the most precise and accurate results on the stability of the decay constant as function of time.

  14. Gamma-ray mirror technology for NDA of spent fuel

    Energy Technology Data Exchange (ETDEWEB)

    Descalle, M. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ruz-Armendariz, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Decker, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Alameda, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brejnholt, N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Soufli, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Robinson, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dreyer, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Pivovaroff, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ziock, K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Chichester, D. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Watson, S. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Trellue, H. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-28

    Direct measurements of gamma rays emitted by fissile material have been proposed as an alternative to measurements of the gamma rays from fission products. From a safeguards applications perspective, direct detection of uranium (U) and plutonium (Pu) K-shell fluorescence emission lines and specific lines from some of their isotopes could lead to improved shipper-receiver difference or input accountability at the start of Pu reprocessing. However, these measurements are difficult to implement when the spent fuel is in the line-of-sight of the detector, as the detector is exposed to high rates dominated by fission product emissions. To overcome the combination of high rates and high background, grazing incidence multilayer mirrors have been proposed as a solution to selectively reflect U and Pu hard X-ray and soft gamma rays in the 90 to 420 keV energy into a high-purity germanium (HPGe) detector shielded from the direct line-of-sight of spent fuel. Several groups demonstrated that K-shell fluorescence lines of U and Pu in spent fuel could be detected with Ge detectors. In the field of hard X-ray optics the performance of reflective multilayer coated reflective optics was demonstrated up to 645 keV at the European Synchrotron Radiation Facility. Initial measurements conducted at Oak Ridge National Laboratory with sealed sources and scoping experiments conducted at the ORNL Irradiated Fuels Examination Laboratory (IFEL) with spent nuclear fuel further demonstrated the pass-band properties of multilayer mirrors for reflecting specific emission lines into 1D and 2D HPGe detectors, respectively.

  15. Voluminal modelling for the characterization of wastes packages by gamma emission computed tomography

    International Nuclear Information System (INIS)

    Pettier, J.L.; Thierry, R.

    2001-01-01

    The aim of this work is to model the measurement process used for multi-photon emission computed tomography on nuclear waste drum. Our model MEPHISTO (Multi-Energy PHoton Imagery through Segmented TOmography) takes into account all phenomena influencing gamma emergent flux and high resolution spectrometric measurements using an HpGe detector through a collimator aperture. These phenomena are absorption and Compton scattering of gamma photons in waste drum, geometrical blur, spatial and energetic response of the detector. The analysis of results shows better localisation and quantification performances compared with a Ray-Driven method. It proves the importance of an accurate modelization of collimated measurements to reduce noise and stabilize iterative image reconstructions. (authors)

  16. Nuclear quadrupole deformations and anisotropic angular correlations between K x rays and gamma rays

    International Nuclear Information System (INIS)

    Khalil, A.E.

    1983-01-01

    Anisotropic angular correlation between gamma rays and the K x rays following the K conversion from nuclei with large static deformations has been studied. A complete theoretical expression for 181 Ta, the second known case of this phenomenon, is presented. This case involves several mixed nuclear transitions which result in 62% of the x rays arising from magnetic dipole internal-conversion processes and 38% arising from electric-quadrupole internal-conversion processes

  17. High efficiency 40 K single-stage Stirling-type pulse tube cryocooler

    Science.gov (United States)

    Wu, X. L.; Chen, L. B.; Pan, C. Z.; Cui, C.; Wang, J. J.; Zhou, Y.

    2017-12-01

    A high efficiency single-stage Stirling-type coaxial pulse tube cryocooler (SPTC) operating at around 40 K has been designed, built and tested. The double-inlet and the inertance tubes together with the gas reservoir were adopted as the phase shifters. Under the conditions of 2.5 MPa charging pressure and 30 Hz operating frequency, the prototype has achieved a no-load temperature of 23.8 K with 330 W of electric input power at a rejection temperature of 279 K. When the input power increases to 400 W, it can achieve a cooling capacity of 4.7 W/40 K while rejecting heat at 279 K yielding an efficiency of 7.02% relative to Carnot. It achieves a cooling capacity of 5 W/40 K with an input power of 450 W. It takes 10 minutes for the SPTC to cool to its no-load temperature of 40 K from 295 K.

  18. The activity of selected gamma radionuclides in the Tatra National Park

    Directory of Open Access Journals (Sweden)

    Kubica Barbara

    2017-01-01

    Full Text Available Cesium is naturally occurring active metal, represented by one stable isotope 133Cs, and number of artificial, unstable, isotopes. The most common artificial isotope of cesium is 137Cs, present in the environment of the Tatra Mountains due to nuclear weapon testing in late `50, and nuclear reactor accident in Chernobyl in 1986. However in recent years the growth in biofuels use for power generation can be the next source of 137Cs emission. Burning wood cultivated on grounds contaminated by 137Cs can introduce secondary emission of this isotope to the atmosphere.This paper presents the results of determination of gamma emitting radionuclides artificial 137Cs and natural 40K in soil samples from the Tatra Mountains. Results show some differences in the vertical distribution of examined radionuclides. It was found that the change of activity of 137Cs in the soil samples depends mostly on the soil density and on the concentration of organic material. The state of “zero” 137Cs activity was developed in the form of maps.

  19. Study on the thermoluminescent properties of K{sub 2}YF{sub 5} and K{sub 2}GdF{sub 5} crystals doped with optically active trivalent ions for gamma and neutrons dosimetry; Estudo das propriedades termoluminescentes de cristais de K{sub 2}YF{sub 5} e K{sub 2}GdF{sub 5} dopados com ions trivalentes opticamente ativos para dosimetria gama e de neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Edna Carla da

    2008-07-01

    In this work, the thermoluminescent (TL) properties of both double potassium yttrium fluoride (K{sub 2}YF{sub 5}) and double potassium gadolinium fluoride (K{sub 2}GdF{sub 5}) crystals doped with optically active rare earth ions were investigated from the point of view of gamma and neutron dosimetry. Crystalline platelets with thickness of about 1 mm, synthesized under hydrothermal conditions, were irradiated in order to study TL sensitivity, as well as dose and energy response, reproducibility and fading, in terms of Ce{sup 3+}, Tb{sup 3+}, Dy{sup 3+}, e Pr{sup 3+} concentrations. The K{sub 2}YF{sub 5} crystals doped with 1.0 at por cent Dy{sup 3+} have been found to have an excellent linear TL response to X and gamma photons, in the range of 0.01 to 10 mGy. The TL output is comparable to that of CaS0{sub 4}:Mn dosemeters. The main peak at 130 deg C has been found to have a TL response for 41.1 keV X-ray energy 32 times higher than that for 662 keV gamma rays. This fact points out that the K{sub 2}Y{sub 0.99}Dy{sub 0.01}F{sub 5} crystals have great potential for X-rays diagnostic and/or industrial radiography. On the other hand, the K{sub 2}GdF{sub 5} crystals doped with 5.0 at por cent Dy{sup 3+} have been found to have the better TL response for gamma and fast neutron radiation, among the dopants studied. For gamma fields the TL response was linear for doses ranging from 0.1 to 200 mGy. The TL peak around 200 deg C can be deconvoluted into four individual peaks, all of them with linear behavior. For fast neutron radiation produced by an {sup 241}Am{sub B}e source, the TL responses for doses ranging from 0.6 to 12 mSv were also linear and comparable to that of commercial TLD-600, irradiated at same conditions. The TL emission due to neutrons was in the high temperature range, above 200 deg C. These results points out that K{sub 2}Gd{sub 0.95}Dy{sub 0.05}F{sub 5} crystals are good candidates for use in neutron dosimetry applications. (author)

  20. Theoretical Study of the Endogenous Production of N-13 in 115 kJ Plasma Focus Device Using Methane Gas

    Science.gov (United States)

    Faghih Haghani, Saeedeh; Sadighzadeh, A.; Talaei, A.; Zaeem, A. A.; Sadat Kiai, S. M.; Heydarnia, A.; Damideh, V.

    2013-08-01

    Mather type plasma focus device with the bank energy of 115 kJ (40 kV, 144μF) was studied for induced activity of N-13; a short-lived radioisotope β+ emitter with 511 keV of gamma rays and has a half-life of t1/2 = 9.93 min through 12C (d, n)13N nuclear reaction. N-13 radioisotope is used in Positron Emission Tomography (PET) for imaging and treatment. In this paper endogenous production of 13N is considered. It is shown by adding 3-4 % CH4 to the chamber, the induced activity of N-13 has increased about 4 %. Our study is representative of producing 106 - 109 Bq induced activity of this SLR in IR-MPF-100 device.

  1. Biodegradation polyurethane derived from vegetable oil irradiated with gamma rays 25 kGy and 100 kGy

    International Nuclear Information System (INIS)

    Santos, Antonia M. dos; Claro Neto, Salvador; Azevedo, Elaine C. de

    2011-01-01

    The environment requires polymers that can be degraded by the action of microorganisms. In this work was studied the biodegradation of polyurethane samples derived from vegetable oil (castor oil), which were irradiated with gamma rays 25 kGy and 100 kGy compared with the same polyurethane without being irradiated. Biodegradation of polyurethane was carried out in culture medium containing the fungus Aspergillus niger by 146 days and the result was evaluated using the technique of thermogravimetric analysis, where there was a change of behavior of the curves TGA / DTG occurred indicating that chemical modifications of molecules present in the structure of the polymer chain, thus confirming that the material has undergone the action of microorganisms. (author)

  2. Dose Response for Monokaryon mycelium of Pleurotus pulmonarius After Acute Gamma Radiation

    International Nuclear Information System (INIS)

    Wan Safina Wan Abdul Razak; Azhar Mohamad; Nie, H.J.

    2016-01-01

    Pleurotus pulmonarius is locally known as Grey oyster. The species is popular and widely cultivated throughout the world mostly in Asia Europe as their simple and low cost production technology and higher biological efficiency. Mutation induction is an alternative ways for improving available commercial strain for better quality traits. Dose response is important in evaluating effects of mutagenesis via acute gamma radiation. Monokaryon mycelium of Pleurotus pulmonarius was exposed to acute gamma radiation ranged from 0 Gy, 0.1 kGy, 0.2 kGy, 0.3 kGy, 0.4 kGy, 0.5 kGy, 0.6 kGy, 0.7 kGy, 0.8 kGy, 0.9 kGy, 1.0 kGy, 1.5 Gy, 2.0 kGy, 3.0 kGy and 4.0 kGy at dose rate 0.013 kGy/ min. growth performance was measured at 2 days interval to get the LD_5_0. Increasing of the irradiation dose found to decrease the growth performance of the monokaryon mycelium. LD_5_0 was revealed at 1.56 kGy for mono karyon mycelium. Discoveries of the works are important for the improvement of Pleurotus species via acute gamma radiation and benefiting to growers and mushroom industries. (author)

  3. Electron cyclotron emission measurements at the stellarator TJ-K

    Energy Technology Data Exchange (ETDEWEB)

    Sichardt, Gabriel; Ramisch, Mirko [Institut fuer Grenzflaechenverfahrenstechnik und Plasmatechnologie, Universitaet Stuttgart (Germany); Koehn, Alf [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany)

    2016-07-01

    Electron temperature (T{sub e}) measurements in the magnetised plasmas of the stellarator TJ-K are currently performed by means of Langmuir probes. The use of these probes is restricted to relatively low temperatures and the measurement of temperature profiles requires the acquisition of the local current-voltage characteristics which limits strongly the sampling rate. As an alternative, T{sub e} can be measured using the electron cyclotron emission (ECE) that is generated by the gyration of electrons in magnetised plasmas. Magnetic field gradients in the plasma lead to a spatial distribution of emission frequencies and thus the measured intensity at a given frequency can be related to its point of origin. The T{sub e} dependence of the intensity then leads to a temperature profile along the line of sight for Maxwellian velocity distributions. A diagnostic system for T{sub e} measurements using ECE is currently being set up at TJ-K. When non-thermal electrons are present the emission spectrum changes dramatically. Therefore, the ECE can also be used to investigate the contribution of fast electrons to previously observed toroidal net currents in TJ-K. Simulations are used to examine the role of electron drift orbits in generating these currents.

  4. Design and Performance of the GAMMA-400 Gamma-Ray Telescope for Dark Matter Searches

    Science.gov (United States)

    Galper, A. M.; Adriani, O.; Aptekar, R. L.; Arkhangelskaja, I. V.; Arkhangelskiy, A. I.; Boezio, M.; Bonvicini, V.; Boyarchuk, K. A.; Fradkin, M. I.; Gusakov, Yu V.; hide

    2012-01-01

    The GAMMA-400 gamma-ray telescope is designed to measure the fluxes of gamma-rays and cosmic-ray electrons (+) positrons, which can be produced by annihilation or decay of the dark matter particles, as well as to survey the celestial sphere in order to study point and extended sources of gamma-rays, measure energy spectra of Galactic and extragalactic diffuse gamma-ray emission, gamma-ray bursts, and gamma-ray emission from the Sun. GAMMA-400 covers the energy range from 100 MeV to 3000 GeV. Its angular resolution is approximately 0.01deg (E(sub gamma) greater than 100 GeV), the energy resolution approximately 1% (E(sub gamma) greater than 10 GeV), and the proton rejection factor approximately 10(exp 6). GAMMA-400 will be installed on the Russian space platform Navigator. The beginning of observations is planned for 2018.

  5. Very high-energy gamma rays from gamma-ray bursts.

    Science.gov (United States)

    Chadwick, Paula M

    2007-05-15

    Very high-energy (VHE) gamma-ray astronomy has undergone a transformation in the last few years, with telescopes of unprecedented sensitivity having greatly expanded the source catalogue. Such progress makes the detection of a gamma-ray burst at the highest energies much more likely than previously. This paper describes the facilities currently operating and their chances for detecting gamma-ray bursts, and reviews predictions for VHE gamma-ray emission from gamma-ray bursts. Results to date are summarized.

  6. Photometry of the 4686 A emission line of gamma(2) Velorum from the South Pole

    International Nuclear Information System (INIS)

    Taylor, M.

    1990-01-01

    An automated optical telescope located at the Amundsen-Scott South Pole station on Antarctica, has been used to obtain more than 78 h of photometry of the He II emission line (4686 A) of the spectroscopic binary gamma(2) Velorum. These data were obtained on seven different days during the 1987 austral winter; the longest continuous run spans 19 h. Two independent period search techniques have been used to search for periodic behavior in the strength of the He II emission line of this Wolf-Rayet star. They are: (1) power spectrum analysis and (2) a first-order sine function fit to the data using least squares. Various multiplicities of a period on the order of 1.3 h with amplitudes of a few percent are found in most of these data. According to recent theoretical models of Wolf-Rayet stars, fluctuations in the He II emission line may indicate vibrational instability in gamma(2) Vel. These pulsations may, in turn, give rise to shocks which propagate outward and which may provide the necessary conditions for periodic changes in the state of a given region of the atmosphere to occur. 15 refs

  7. 40 CFR 49.124 - Rule for limiting visible emissions.

    Science.gov (United States)

    2010-07-01

    ...% opacity limit. (3) The visible emissions from an oil-fired boiler or solid fuel-fired boiler that... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Rule for limiting visible emissions. 49... Application to Indian Reservations in Epa Region 10 § 49.124 Rule for limiting visible emissions. (a) What is...

  8. Attenuation studies near K-absorption edges using Compton scattered 241Am gamma rays

    International Nuclear Information System (INIS)

    Abdullah, K.K.; Ramachandran, N.; Karunakaran Nair, K.; Babu, B.R.S.; Joseph, Antony; Thomas, Rajive; Varier, K.M.

    2008-01-01

    We have carried out photon attenuation measurements at several energies in the range from 49.38 keV to 57.96 keV around the K-absorption edges of the rare earth elements Sm, Eu, Gd, Tb, Dy and Er using 59.54 keV gamma rays from 241 Am source after Compton scattering from an aluminium target. Pellets of oxides of the rare earth elements were chosen as mixture absorbers in these investigations. A narrow beam good geometry set-up was used for the attenuation measurements. The scattered gamma rays were detected by an HPGe detector. The results are consistent with theoretical values derived from the XCOM package. (author)

  9. Correlation between X-ray and high energy gamma-ray emission form Cygnus X-3

    International Nuclear Information System (INIS)

    Weekes, T.C.; Danaher, S.; Fegan, D.J.; Porter, N.A.

    1981-01-01

    In May-June 1980, the 4.8 hour modulated X-ray flux from Cygnus X-3 underwent a significant change in the shape of the light curve; this change correlates with the peak in the high-energy (E > 2 x 10 12 eV) gamma ray emission at the same epoch. (orig.)

  10. Characteristics of a single photon emission tomography system with a wide field gamma camera

    International Nuclear Information System (INIS)

    Mathonnat, F.; Soussaline, F.; Todd-Pokropek, A.E.; Kellershohn, C.

    1979-01-01

    This text summarizes a work study describing the imagery possibilities of a single photon emission tomography system composed of a conventional wide field gamma camera, connected to a computer. The encouraging results achieved on the various phantoms studied suggest a significant development of this technique in clinical work in Nuclear Medicine Departments [fr

  11. Kemission form medium and high-Z materials irradiated by femtosecond laser pulses

    International Nuclear Information System (INIS)

    Limpouch, J.; Klimo, O.; Zhavoronkov, N.; Andreev, A.A.

    2006-01-01

    Complete test of publication follows. Fast electrons are created at the target surface during the interaction of high intensity ultra short laser pulses with solids. Fast electrons penetrate deep into the target where they generate K-α and Bremsstrahlung radiation. Generated high brightness K-α pulses offer the prospect of creating a cheap and compact X-ray source, posing a promising alternative to synchrotron radiation, e.g. in medical application and in material science. With an increase in laser intensity, efficient X-ray emission in the multi-keV range with pulse duration shorter than few picoseconds is expected. This short incoherent but monochromatic X-ray emission synchronized with laser pulses may be used for time-resolved measurements. Acceleration of fast electrons, their transport and K-α photon generation and emission from the target surface in both forward and backward directions are studied here numerically. The results are compared to recent experiments studying Kemission from the front and rear surface of copper foil targets of various thicknesses and for various parameters of the laser plasma interaction. One-dimensional PIC simulations coupled with 3D time-resolved Monte Carlo simulations show that account of ionization processes and of density profile formed by laser ASE emission is essential for reliable explanation of experimental data. While sub-relativistic intensities are optimum for laser energy transformation into Kemission for medium-Z targets, relativistic laser intensities have to be used for hard X-ray generation in high-Z materials. The cross-section for K-α shell ionization of high-Z elements by electrons increases or remains approximately constant within a factor of two at relativistic electron energies up to electron energies in the 100-MeV range. Moreover, the splitting ratio of K-α photon emission to Auger electron emission is favorable for high-Z materials, and thus efficient Kemission is possible. In our

  12. Evaluation and measurement of prompt k0-factors to use in prompt gamma-ray neutron activation analysis

    International Nuclear Information System (INIS)

    Goswami, A.; Nair, A.G.C.; Acharya, R.N.; Sudarshan, K.; Scindia, Y.M.; Reddy, A.V.R.; Manohar, S.B.

    2000-01-01

    The determination of experimental k 0 -factors is important due to uncertainties on absolute values of cross sections and prompt gamma-ray intensities. Determination of absolute full-energy peak detection efficiency and elemental sensitivity are required to obtain experimental k 0 -factor

  13. Observations of Short Gamma-Ray Bursts: Prompt Emission and Afterglow

    Science.gov (United States)

    Berger, Edo

    2011-09-01

    The study of short gamma-ray bursts has been revolutionized by the discovery of afterglows and host galaxies. In this talk I will review observations of the prompt emission, afterglows, and host galaxies, primarily as they pertain to the nature of the progenitor systems. The bulk of the evidence points to the merger of compact objects (NS-NS or NS-BH) making short GRBs the prime candidate for gravitational wave detections with the next generation detectors. This work is partially supported by funds from NASA (through the Swift and Chandra GO programs) and the NSF through an AAG grant.

  14. Pre-scission particle and gamma-ray emission in heavy-ion induced fission

    International Nuclear Information System (INIS)

    Newton, J.O.

    1989-02-01

    An introduction is given to the physics of the equilibrium transition model and of dissipative nuclear dynamics. Experimental data on pre-scission particle and gamma-ray emission and their interpretation are reviewed. They appear to indicate overdamped motion of the nuclear fluid. A time scale for compound-nucleus fission of about 30x10 -21 sec or greater is indicated, whilst that for quasi- or fast-fission is somewhat shorter. 99 refs., 28 figs

  15. On The gamma-ray emission from Reticulum II and other dwarf galaxies

    Energy Technology Data Exchange (ETDEWEB)

    Hooper, Dan; Linden, Tim

    2015-09-01

    The recent discovery of ten new dwarf galaxy candidates by the Dark Energy Survey (DES) and the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) could increase the Fermi Gamma-Ray Space Telescope's sensitivity to annihilating dark matter particles, potentially enabling a definitive test of the dark matter interpretation of the long-standing Galactic Center gamma-ray excess. In this paper, we compare the previous analyses of Fermi data from the directions of the new dwarf candidates (including the relatively nearby Reticulum II) and perform our own analysis, with the goal of establishing the statistical significance of any gamma-ray signal from these sources. We confirm the presence of an excess from Reticulum II, with a spectral shape that is compatible with the Galactic Center signal. The significance of this emission is greater than that observed from 99.84% of randomly chosen high-latitude blank-sky locations, corresponding to a local detection significance of 3.2σ. We caution that any dark matter interpretation of this excess must be validated through observations of additional dwarf spheroidal galaxies, and improved calculations of the relative J-factor of dwarf spheroidal galaxies. We improve upon the standard blank-sky calibration approach through the use of multi-wavelength catalogs, which allow us to avoid regions that are likely to contain unresolved gamma-ray sources.

  16. Pulsed Gamma-Rays From PSR J2021 3651 with the Fermi Large Area Telescope

    International Nuclear Information System (INIS)

    Abdo, Aous A.; Ackermann, M.; Ajello, Marco; Atwood, William B.; Baldini, L.; Ballet, J.; Barbiellini, Guido; Bastieri, Denis; Battelino, Milan; Baughman, B.M.; Bechtol, K.; Bellazzini, Ronaldo; Berenji, Bijan; Bloom, Elliott D.; Bogaert, G.; Borgland, Anders W.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; Burnett, Thompson H.

    2009-01-01

    We report the detection of pulsed gamma-rays from the young, spin-powered radio pulsar PSR J2021+3651 using data acquired with the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope (formerly GLAST). The light curve consists of two narrow peaks of similar amplitude separated by 0.468 ± 0.002 in phase. The first peak lags the maximum of the 2 GHz radio pulse by 0.162 ± 0.004 ± 0.01 in phase. The integral gamma-ray photon flux above 100 MeV is (56 ± 3 ± 11) x 10 -8 cm -2 s -1 . The photon spectrum is well-described by an exponentially cut-off power law of the form dF/dE = kE -# Gamma#e (-E/E c ) where the energy E is expressed in GeV. The photon index is Γ = 1.5 ± 0.1 ± 0.1 and the exponential cut-off is E c = 2.4 ± 0.3 ± 0.5 GeV. The first uncertainty is statistical and the second is systematic. The integral photon flux of the bridge is approximately 10% of the pulsed emission, and the upper limit on off-pulse gamma-ray emission from a putative pulsar wind nebula is -2 but a poorly constrained magnetic geometry. Re-analysis of Chandra data enhanced the significance of the weak X-ray pulsations, and the first peak is roughly phase-aligned with the first gamma-ray peak. We discuss the emission region and beaming geometry based on the shape and spectrum of the gamma-ray light curve combined with radio and X-ray measurements, and the implications for the pulsar distance. Gamma-ray emission from the polar cap region seems unlikely for this pulsar.

  17. Extragalactic Gamma-Ray Astrophysics

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    During the last decades, various classes of radio-loud active galactic nuclei have been established as sources of high-energy radiation extending over a very broad range from soft gamma-rays (photon energies E~MeV) up to very-high-energy gamma-rays (E>100 GeV). These include blazars of different types, as well as young and evolved radio galaxies. The observed gamma-ray emission from such implies efficient particle acceleration processes taking place in highly magnetized and relativistic jets produced by supermassive black holes, processes that have yet to be identified and properly understood. In addition, nearby starforming and starburst galaxies, some of which host radio-quiet Seyfert-type nuclei, have been detected in the gamma-ray range as well. In their cases, the observed gamma-ray emission is due to non-thermal activity in the interstellar medium, possibly including also a contribution from accretion disks and nuclear outflows. Finally, the high-energy emission from clusters of galaxies remains elusive...

  18. Updated studies of determining gamma at LHCb with the decays $B^{+-} \\to D(K\\pi,KK,\\pi\\pi)K^{+-}$

    CERN Document Server

    Patel, M

    2009-01-01

    The selection efficiencies and backgrounds for the decays B+- -> DK+-, where the D denotes a D0bar or D0 which decays into the two-body final states Kpi, KK, pipi, are determined from simulation studies. These are used to estimate the precision with which LHCb will be able to measure the CKM angle gamma. With a data set corresponding to an intergrated luminosity of 2fb-1, a precision of 9.9-11.3 degrees is expected, depending on the strong phase difference between D0 -> K+pi- and D0->K-pi+ decays.

  19. Influence of Gamma Irradiation on Biogenic Amine Contents and Pathogenic Bacteria in Spinach

    International Nuclear Information System (INIS)

    Ali, H.A.S.

    2015-01-01

    This study was carried out to evaluate the effect of gamma irradiation at doses 1, 2, 4 and 6 kGy as compared with blanching at 95°C/3 min on biogenic amine contents and pathogenic bacteria in spinach leaves (Spinacia oleracea L.). The results indicated that tryptamine and β- phenylethylamine were not detected while histamine was the major amine detected at concentration of 12.55 mg/100g of wet weight. Blanching at 95°C/3 min significantly reduced the content of histamine, putrescine and tyramine in spinach while significantly increased the content of cadaverine. Gamma irradiation at different doses significantly reduced the contents of histamine and tyramine while significantly increased the content of cadaverine. However, putrescine content was increased significantly after subjected to doses 1 and 2 kGy while the doses 4 and 6 kGy significantly reduced it. Regarding to microbiological analysis in spinach, it could be noticed that total bacterial count, Enterobacteriaceae, coliform group, yeast, mould, Staphylococcus aureus and Salmonella spp. in fresh spinach were 5.97, 4.40, 2.53, 2.11, 1.40, 1.48 and 1.18 log cfu/g, respectively. Changes in microbiological characters (cfu/g) in spinach by different gamma irradiation doses and blanching were also followed. It could be noticed that the total bacterial count, Enterobacteriaceae, coliform group, yeast, mould, Staphylococcus aureus and Salmonella spp. were significantly decreased after treatment with blanching and gamma irradiation and these microorganisms were not detected after being subjected to 4 and 6 kGy. It could be concluded that blanching at 95°C/3 min or gamma irradiation at dose 2 kGy can be used to control the pathogenic bacteria and reduce biogenic amine (histamine, putrescine and tyramine) in spinach

  20. Gamma-ray emission from star-forming complexes observed by MAGIC: The cases of W51 and HESS J1857+026

    Directory of Open Access Journals (Sweden)

    Reichardt I.

    2015-01-01

    Full Text Available Massive star-forming regions assemble a large number of young stars with remnants of stellar evolution and a very dense environment. Therefore, particles accelerated in supernova remnants and pulsar wind nebulae encounter optimal conditions for interacting with target material and photon fields, and thus produce gamma-ray emission. However, observations are challenging because multiple phenomena may appear entangled within the resolution of current gamma-ray telescopes. We report on MAGIC observations aimed to understand the nature of the emission from the star-forming region W51 and the unidentified source HESS J1857+026. While gamma-ray emission from W51 is dominated by the interaction of the supernova remnant W51C with dense molecular clouds, HESS J1857+026 is associated to the pulsar wind nebula from PSR J1856+0245. However, an additional source is resolved north of HESSJ1857+026, with sufficient separation to determine that it cannot be powered by the same pulsar. We search for multiwavelength data to determine the origin of the new source.

  1. Pulsed Gamma-Rays From PSR J2021 3651 with the Fermi Large Area Telescope

    Energy Technology Data Exchange (ETDEWEB)

    Abdo, Aous A.; /Naval Research Lab, Wash., D.C.; Ackermann, M.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Ajello, Marco; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Atwood, William B.; /UC, Santa Cruz; Baldini, L.; /INFN, Pisa; Ballet, J.; /DAPNIA, Saclay; Barbiellini, Guido; /INFN, Trieste /Trieste U.; Bastieri, Denis; /INFN, Padua /Padua U.; Battelino, Milan; /Royal Inst. Tech., Stockholm; Baughman, B.M.; /Ohio State U.; Bechtol, K.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bellazzini, Ronaldo; /INFN, Pisa; Berenji, Bijan; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bloom, Elliott D.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bogaert, G.; /Ecole Polytechnique; Borgland, Anders W.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bregeon, J.; /INFN, Pisa; Brez, A.; /INFN, Pisa; Brigida, M.; /Bari U. /INFN, Bari; Bruel, P.; /Ecole Polytechnique; Burnett, Thompson H.; /Washington U., Seattle /Bari U. /INFN, Bari /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Columbia U. /IASF, Milan /IASF, Milan /DAPNIA, Saclay /INFN, Perugia /Perugia U. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /George Mason U. /Naval Research Lab, Wash., D.C. /IASF, Milan /IASF, Milan /NASA, Goddard /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /INFN, Perugia /Perugia U. /LPCE, Orleans /Montpellier U. /Sonoma State U. /Royal Inst. Tech., Stockholm /Stockholm U. /ASI, Rome /NRAO, Charlottesville /Naval Research Lab, Wash., D.C. /INFN, Trieste /Pavia U. /Bari U. /INFN, Bari /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /UC, Santa Cruz /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /CENBG, Gradignan /CENBG, Gradignan /Manchester U. /Montpellier U. /Bari U. /INFN, Bari; /more authors..

    2011-11-30

    We report the detection of pulsed gamma-rays from the young, spin-powered radio pulsar PSR J2021+3651 using data acquired with the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope (formerly GLAST). The light curve consists of two narrow peaks of similar amplitude separated by 0.468 {+-} 0.002 in phase. The first peak lags the maximum of the 2 GHz radio pulse by 0.162 {+-} 0.004 {+-} 0.01 in phase. The integral gamma-ray photon flux above 100 MeV is (56 {+-} 3 {+-} 11) x 10{sup -8} cm{sup -2} s{sup -1}. The photon spectrum is well-described by an exponentially cut-off power law of the form dF/dE = kE{sup -{Gamma}}e{sup (-E/E{sub c})} where the energy E is expressed in GeV. The photon index is {Gamma} = 1.5 {+-} 0.1 {+-} 0.1 and the exponential cut-off is E{sub c} = 2.4 {+-} 0.3 {+-} 0.5 GeV. The first uncertainty is statistical and the second is systematic. The integral photon flux of the bridge is approximately 10% of the pulsed emission, and the upper limit on off-pulse gamma-ray emission from a putative pulsar wind nebula is < 10% of the pulsed emission at the 95% confidence level. Radio polarization measurements yield a rotation measure of RM = 524 {+-} 4 rad m{sup -2} but a poorly constrained magnetic geometry. Re-analysis of Chandra data enhanced the significance of the weak X-ray pulsations, and the first peak is roughly phase-aligned with the first gamma-ray peak. We discuss the emission region and beaming geometry based on the shape and spectrum of the gamma-ray light curve combined with radio and X-ray measurements, and the implications for the pulsar distance. Gamma-ray emission from the polar cap region seems unlikely for this pulsar.

  2. Pre-equilibrium gamma emissions

    International Nuclear Information System (INIS)

    Ghosh, Sudip

    1993-01-01

    Together with the direct reaction and the compound nuclear emissions the pre-equilibrium (PEQ) or pre-compound processes give a fairly complete picture of nuclear reactions induced by light ions at energies of some tens of MeV. PEQ particle emissions covering the higher energy continuum spectra have been investigated in detail both experimentally and theoretically. In contrast, very little work has been done on PEQ γ- emissions. The reason is that in spite of extensive work done on PEQ particle emissions, the mechanism is not yet fully understood. Also, the PEQ γ-emission cross-sections (∼ micro barns) are very small compared to the PEQ particle emission cross-sections (∼ milli barns). Yet apart from the academic interest the understanding of PEQ γ-emissions is important for applied fusion research etc. In this paper the PEQ γ-emissions is discussed and the work done in this field is reviewed. (author). 14 refs

  3. THERMAL EMISSION IN THE EARLY X-RAY AFTERGLOWS OF GAMMA-RAY BURSTS: FOLLOWING THE PROMPT PHASE TO LATE TIMES

    Energy Technology Data Exchange (ETDEWEB)

    Friis, Mette [Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhagi 5, 107 Reykjavik (Iceland); Watson, Darach, E-mail: mef4@hi.is, E-mail: darach@dark-cosmology.dk [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen O (Denmark)

    2013-07-01

    Thermal radiation, peaking in soft X-rays, has now been detected in a handful of gamma-ray burst (GRB) afterglows and has to date been interpreted as shock break-out of the GRB's progenitor star. We present a search for thermal emission in the early X-ray afterglows of a sample of Swift bursts selected by their brightness in X-rays at early times. We identify a clear thermal component in eight GRBs and track the evolution. We show that at least some of the emission must come from highly relativistic material since two show an apparent super-luminal expansion of the thermal component. Furthermore, we determine very large luminosities and high temperatures for many of the components-too high to originate in a supernova shock break-out. Instead, we suggest that the component may be modeled as late photospheric emission from the jet, linking it to the apparently thermal component observed in the prompt emission of some GRBs at gamma-ray and hard X-ray energies. By comparing the parameters from the prompt emission and the early afterglow emission, we find that the results are compatible with the interpretation that we are observing the prompt quasi-thermal emission component in soft X-rays at a later point in its evolution.

  4. 40 CFR 86.117-96 - Evaporative emission enclosure calibrations.

    Science.gov (United States)

    2010-07-01

    ... periodic determination of enclosure background emissions. Prior to its introduction into service, annually... procedure: (1) Carefully measure the internal length, width and height of the enclosure, accounting for... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Evaporative emission enclosure...

  5. Correction of Doppler broadening of {gamma}-ray lines induced by particle emission in heavy-ion induced fusion-evaporation reactions

    Energy Technology Data Exchange (ETDEWEB)

    Nyberg, J; Seweryniak, D; Fahlander, C; Insua-Cao, P [Uppsala Univ. (Sweden). Dept. of Radiation Sciences; Johnson, A; Cederwall, B [Manne Siegbahn Inst. of Physics, Stockholm (Sweden); [Royal Inst. of Tech., Stockholm (Sweden); Adamides, E; Piiparinen, M [National Centre for Scientific Research, Ag. Paraskevi, Attiki (Greece); Atac, A; Norlin, L O [Niels Bohr Inst., Copenhagen (Denmark); Ideguchi, E; Mitarai, S [Kyushu Univ., Fukuoka (Japan). Dept. of Physics; Julin, R; Juutinen, S; Tormanen, S; Virtanen, A [Jyvaeskylae Univ. (Finland). Dept. of Physics; Karczmarczyk, W; Kownacki, J [Warsaw Univ. (Poland); Schubart, R [Hahn-Meitner-Institut Berlin GmbH (Germany)

    1992-08-01

    The effect of particle emission on the peak shape of {gamma}-ray lines have been investigated using the NORDBALL detector system. By detecting neutrons, protons and {alpha} particles emitted in the {sup 32}S (95 MeV) + {sup 27}Al reaction, the energy and direction of emission of the residual nuclei could be determined and subsequently used for an event-by -event Doppler correction of the detected {gamma} rays. Extensive Monte Carlo simulations were performed to study how the different Doppler phenomena influence the peak shape and in particular which particle detector properties are important for the Doppler correction. (author). 2 refs., 1 tab., 4 figs.

  6. X-Ray Spectral Diagnostics of Gamma-Ray Burst Environments.

    Science.gov (United States)

    Paerels; Kuulkers; Heise; Liedahl

    2000-05-20

    Recently, detection of discrete features in the X-ray afterglow spectra of GRB 970508 and GRB 970828 was reported. The most natural interpretation of these features is that they are redshifted Fe K emission complexes. The identification of the line emission mechanism has drastic implications for the inferred mass of radiating material and hence the nature of the burst site. X-ray spectroscopy provides a direct observational constraint on these properties of gamma-ray bursters. We briefly discuss how these constraints arise in the context of an application to the spectrum of GRB 970508.

  7. Search for Gamma-Ray Emission from Local Primordial Black Holes with the Fermi Large Area Telescope

    Science.gov (United States)

    Ackermann, M.; Atwood, W. B.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bellazzini, R.; Berenji, B.; Bissaldi, E.; Blandford, R. D.; Bloom, E. D.; Bonino, R.; Bottacini, E.; Bregeon, J.; Bruel, P.; Buehler, R.; Cameron, R. A.; Caputo, R.; Caraveo, P. A.; Cavazzuti, E.; Charles, E.; Chekhtman, A.; Cheung, C. C.; Chiaro, G.; Ciprini, S.; Cohen-Tanugi, J.; Conrad, J.; Costantin, D.; D’Ammando, F.; de Palma, F.; Digel, S. W.; Di Lalla, N.; Di Mauro, M.; Di Venere, L.; Favuzzi, C.; Fegan, S. J.; Focke, W. B.; Franckowiak, A.; Fukazawa, Y.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Giglietto, N.; Giordano, F.; Giroletti, M.; Green, D.; Grenier, I. A.; Guillemot, L.; Guiriec, S.; Horan, D.; Jóhannesson, G.; Johnson, C.; Kensei, S.; Kocevski, D.; Kuss, M.; Larsson, S.; Latronico, L.; Li, J.; Longo, F.; Loparco, F.; Lovellette, M. N.; Lubrano, P.; Magill, J. D.; Maldera, S.; Malyshev, D.; Manfreda, A.; Mazziotta, M. N.; McEnery, J. E.; Meyer, M.; Michelson, P. F.; Mitthumsiri, W.; Mizuno, T.; Monzani, M. E.; Moretti, E.; Morselli, A.; Moskalenko, I. V.; Negro, M.; Nuss, E.; Ojha, R.; Omodei, N.; Orienti, M.; Orlando, E.; Ormes, J. F.; Palatiello, M.; Paliya, V. S.; Paneque, D.; Persic, M.; Pesce-Rollins, M.; Piron, F.; Principe, G.; Rainò, S.; Rando, R.; Razzano, M.; Razzaque, S.; Reimer, A.; Reimer, O.; Ritz, S.; Sánchez-Conde, M.; Sgrò, C.; Siskind, E. J.; Spada, F.; Spandre, G.; Spinelli, P.; Suson, D. J.; Tajima, H.; Thayer, J. G.; Thayer, J. B.; Torres, D. F.; Tosti, G.; Troja, E.; Valverde, J.; Vianello, G.; Wood, K.; Wood, M.; Zaharijas, G.

    2018-04-01

    Black holes with masses below approximately 1015 g are expected to emit gamma-rays with energies above a few tens of MeV, which can be detected by the Fermi Large Area Telescope (LAT). Although black holes with these masses cannot be formed as a result of stellar evolution, they may have formed in the early universe and are therefore called primordial black holes (PBHs). Previous searches for PBHs have focused on either short-timescale bursts or the contribution of PBHs to the isotropic gamma-ray emission. We show that, in cases of individual PBHs, the Fermi-LAT is most sensitive to PBHs with temperatures above approximately 16 GeV and masses 6 × 1011 g, which it can detect out to a distance of about 0.03 pc. These PBHs have a remaining lifetime of months to years at the start of the Fermi mission. They would appear as potentially moving point sources with gamma-ray emission that become spectrally harder and brighter with time until the PBH completely evaporates. In this paper, we develop a new algorithm to detect the proper motion of gamma-ray point sources, and apply it to 318 unassociated point sources at a high galactic latitude in the third Fermi-LAT source catalog. None of the unassociated point sources with spectra consistent with PBH evaporation show significant proper motion. Using the nondetection of PBH candidates, we derive a 99% confidence limit on the PBH evaporation rate in the vicinity of Earth, {\\dot{ρ }}PBH}< 7.2× {10}3 {pc}}-3 {yr}}-1. This limit is similar to the limits obtained with ground-based gamma-ray observatories.

  8. Evaluation of gamma and neutron irradiation effects on the properties of mica film capacitors

    International Nuclear Information System (INIS)

    Roy, Rajesh; Pandya, Arun

    2005-01-01

    We present an investigation of gamma and neutron radiation effects on mica film capacitors from an electrical point of view. We have studied quantitatively the effects of gamma and neutron irradiation on mica film capacitors of thickness, 20 and 40 μm (0.7874 and 1.5748 mil) with two different areas, 01 and 04 cm 2 . The capacitance has been measured at room temperature in the frequency range 100 Hz-10 MHz. Negligible change in the capacitance due to high gamma dose of 60 Co, 15 kGy at dose rate 0.25 kGy/h, has been observed. However, appreciable change in the capacitance has been observed due to low doses of fast neutrons (cumulative dose, 115 cGy) with flux ∼ 9.925 X 10 7 neutrons/cm 2 h from 252 Cf neutron source of fluence, 2.5 x 10 7 neutrons/s. We have also observed that the impact of gamma and neutron irradiation is more at frequencies higher than 10 kHz, These results show that the mica capacitors do not show any radiation response below 10 kHz. The study shows the radiation response of mica film capacitors to gamma and fast neutron radiations. Mica capacitors show low gamma radiation response in comparison to fast neutron radiation, because a total dose of kGy order has been given by gamma source and only few cGy dose has been given by fast neutron source. (author)

  9. Embedded gamma spectrometry: new algorithms for spectral analysis

    International Nuclear Information System (INIS)

    Martin-Burtart, Nicolas

    2012-01-01

    Airborne gamma spectrometry was first used for mining prospecting. Three main families were looked for: K-40, U-238 and Th-232. The Chernobyl accident acted as a trigger and for the last fifteen years, a lot of new systems have been developed for intervention in case of nuclear accident or environmental purposes. Depending on their uses, new algorithms were developed, mainly for medium or high energy signal extraction. These spectral regions are characteristics of natural emissions (K-40, U-238 and Th-232 decay chains) and fissions products (mainly Cs-137 and Co-60). Below 400 keV, where special nuclear materials emit, these methods can still be used but are greatly imprecise. A new algorithm called 2-windows (extended to 3), was developed. It allows an accurate extraction, taking the flight altitude into account to minimize false detection. Watching radioactive materials traffic appeared with homeland security policy a few years ago. This particular use of dedicated sensors require a new type of algorithms. Before, one algorithm was very efficient for a particular nuclide or spectral region. Now, we need algorithm able to detect an anomaly wherever it is and whatever it is: industrial, medical or SNM. This work identified two families of methods working under these circumstances. Finally, anomalies have to be identified. IAEA recommend to watch around 30 radionuclides. A brand new identification algorithm was developed, using several rays per element and avoiding identifications conflicts. (author) [fr

  10. Fruit extracts of Momordica charantia potentiate glucose uptake and up-regulate Glut-4, PPAR gamma and PI3K.

    Science.gov (United States)

    Kumar, Ramadhar; Balaji, S; Uma, T S; Sehgal, P K

    2009-12-10

    Momordica charantia fruit is a widely used traditional medicinal herb as, anti-diabetic, anti-HIV, anti-ulcer, anti-inflammatory, anti-leukemic, anti-microbial, and anti-tumor. The present study is undertaken to investigate the possible mode of action of fruit extracts derived from Momordica charantia (MC) and study its pharmacological effects for controlling diabetic mellitus. Effects of aqueous and chloroform extracts of Momordica charantia fruit on glucose uptake and up-regulation of glucose transporter (Glut-4), peroxisome proliferator activator receptor gamma (PPAR gamma) and phosphatidylinositol-3 kinase (PI3K), were investigated to show its efficacy as a hypoglycaemic agent. Dose dependent glucose uptake assay was performed on L6 myotubes using 2-deoxy-D-[1-(3)H] glucose. Up-regulatory effects of the extracts on the mRNA expression level of Glut-4, PPAR gamma and PI3K have been studied. The association of Momordica charantia with the aqueous and chloroform extracts of Momordica charantia fruit at 6 microg/ml has shown significant up-regulatory effect, respectively, by 3.6-, 2.8- and 3.8-fold on the battery of targets Glut-4, PPAR gamma and PI3K involved in glucose transport. The up-regulation of glucose uptake was comparable with insulin and rosiglitazone which was approximately 2-fold over the control. Moreover, the inhibitory effect of the cyclohexamide on Momordica charantia fruit extract mediated glucose uptake suggested the requirement of new protein synthesis for the enhanced glucose uptake. This study demonstrated the significance of Glut-4, PPAR gamma and PI3K up-regulation by Momordica charantia in augmenting the glucose uptake and homeostasis.

  11. Modeling the Broad-Band Emission from the Gamma-Ray Emitting Narrow-Line Seyfert-1 Galaxies 1H 0323+342 and B2 0954+25A

    International Nuclear Information System (INIS)

    Arrieta-Lobo, Maialen; Boisson, Catherine; Zech, Andreas

    2017-01-01

    Prior to the Fermi-LAT era, only two classes of Active Galactic Nuclei (AGN) were thought to harbor relativistic jets that radiate up to gamma-ray energies: blazars and radio galaxies. The detection of variable gamma-ray emission from Narrow Line Seyfert 1 (NLSy1) galaxies has put them on the spotlight as a new class of gamma-ray emitting AGN. In this respect, gamma-ray emitting NLSy1s seem to be situated between blazars (dominated by non-thermal emission) and Seyferts (accretion disc dominated). In this work, we model the Spectral Energy Distribution (SED) of two gamma-loud NLSy1s, 1H 0323+342 and B2 0954+25A, during quiescent and flaring episodes via a multi-component radiative model that features a relativistic jet and external photon fields from the torus, disc, corona and Broad Line Region (BLR). We find that the interpretation of the high-energy emission of jetted NLSy1s requires taking into account Inverse Compton emission from particles in the relativistic jet that interact with external photon fields. Minimal changes are applied to the model parameters to transition from average to flaring states. In this scenario, the observed variability is explained mainly by means of changes in the jet density and Doppler factor.

  12. Modeling the Broad-Band Emission from the Gamma-Ray Emitting Narrow-Line Seyfert-1 Galaxies 1H 0323+342 and B2 0954+25A

    Energy Technology Data Exchange (ETDEWEB)

    Arrieta-Lobo, Maialen; Boisson, Catherine; Zech, Andreas, E-mail: maialen.arrieta@obspm.fr [Laboratoire Univers et Theories, Observatoire de Paris, CNRS, Université Paris-Diderot, PSL Research University, Meudon (France)

    2017-12-08

    Prior to the Fermi-LAT era, only two classes of Active Galactic Nuclei (AGN) were thought to harbor relativistic jets that radiate up to gamma-ray energies: blazars and radio galaxies. The detection of variable gamma-ray emission from Narrow Line Seyfert 1 (NLSy1) galaxies has put them on the spotlight as a new class of gamma-ray emitting AGN. In this respect, gamma-ray emitting NLSy1s seem to be situated between blazars (dominated by non-thermal emission) and Seyferts (accretion disc dominated). In this work, we model the Spectral Energy Distribution (SED) of two gamma-loud NLSy1s, 1H 0323+342 and B2 0954+25A, during quiescent and flaring episodes via a multi-component radiative model that features a relativistic jet and external photon fields from the torus, disc, corona and Broad Line Region (BLR). We find that the interpretation of the high-energy emission of jetted NLSy1s requires taking into account Inverse Compton emission from particles in the relativistic jet that interact with external photon fields. Minimal changes are applied to the model parameters to transition from average to flaring states. In this scenario, the observed variability is explained mainly by means of changes in the jet density and Doppler factor.

  13. Towards the measurement of photon polarisation in the decay $B^+ \\to K^+ π^- π^+ \\gamma$

    CERN Document Server

    AUTHOR|(CDS)2083955; Blanc, Frederic

    This thesis presents a study of the flavour-changing neutral-current radiative $B^+ \\rightarrow K^+ \\pi^- \\pi^+ \\gamma$ decay performed using $3\\, \\rm{fb}^{-1}$ of data collected with the LHCb detector in proton-proton collisions at $7$ and $8\\,$TeV centre-of-mass energies. The study of radiative decays with three scalar hadrons in the final state gives access to the polarisation of the photon, one of the very few predictions of the Standard Model of particle physics that has not been precisely tested experimentally and that is sensitive to new physics effects in the $b \\rightarrow s \\gamma$ penguin loop. Nearly $14\\,000$ signal events, containing all possible intermediate resonances with a $K^+ \\pi^- \\pi^+$ final state in the $[1,2]\\, \\rm{GeV}/\\it{c}^2$ mass interval, are reconstructed and selected in the data sample. The distribution of the angle of the photon direction with respect to the plane defined by the final-state hadrons in their rest frame is studied in intervals of $K^+ \\pi^- \\pi^+$ mass and the...

  14. 40 CFR 65.46 - Alternative means of emission limitation.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Alternative means of emission limitation. 65.46 Section 65.46 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Storage Vessels § 65.46 Alternative means of emission...

  15. Search for Doppler-shifted gamma-ray emission from SS 433 using the SMM spectrometer

    International Nuclear Information System (INIS)

    Geldzahler, B.J.; Share, G.H.; Kinzer, R.L.; Magura, J.; Chupp, E.L.

    1989-01-01

    Data accumulated from 1980 to 1983 with the Gamma Ray Spectrometer aboard NASA's Solar Maximum Mission (SMM) satellite were searched for evidence of red and blue Doppler-shifted 1.37 MeV Mg-24 nuclear lines from SS 433. The SMM data base covers 270 days when SS 433 was in the field of view and includes periods of radio flaring and quiescence. No evidence was found for Doppler-shifted line emission in any of the spectra. The range of 3-sigma upper limits for individual 9 day integration periods was 0.0008-0.0023 photons/sq cm per sec for the blue beam, encompassing the reported about 1.5 MeV line, and 0.0008-0.002 photons/sq cm per sec for the red beam, encompassing the reported about 1.2 MeV line; the average 3-sigma upper limit in each beam for shifted about 1.37 MeV lines is 0.0015 photons/sq cm per sec for single 9 day integrations. The 3-sigma upper limit on 1.37 MeV gamma-ray emission over 23 9-day integration intervals for the red beam and 28 intervals for the blue beam is 0.0002 photons/sq cm per sec. These new limits from SMM can be reconciled with the HEAO 3 results only if SS 433 emits gamma radiation at or above the SMM sensitivity limit on rare occasions due to variable physical conditions in the system. 19 refs

  16. Search for Doppler-shifted gamma-ray emission from SS 433 using the SMM spectrometer

    Science.gov (United States)

    Geldzahler, B. J.; Share, G. H.; Kinzer, R. L.; Magura, J.; Chupp, E. L.

    1989-01-01

    Data accumulated from 1980 to 1983 with the Gamma Ray Spectrometer aboard NASA's Solar Maximum Mission (SMM) satellite were searched for evidence of red and blue Doppler-shifted 1.37 MeV Mg-24 nuclear lines from SS 433. The SMM data base covers 270 days when SS 433 was in the field of view and includes periods of radio flaring and quiescence. No evidence was found for Doppler-shifted line emission in any of the spectra. The range of 3-sigma upper limits for individual 9 day integration periods was 0.0008-0.0023 photons/sq cm per sec for the blue beam, encompassing the reported about 1.5 MeV line, and 0.0008-0.002 photons/sq cm per sec for the red beam, encompassing the reported about 1.2 MeV line; the average 3-sigma upper limit in each beam for shifted about 1.37 MeV lines is 0.0015 photons/sq cm per sec for single 9 day integrations. The 3-sigma upper limit on 1.37 MeV gamma-ray emission over 23 9-day integration intervals for the red beam and 28 intervals for the blue beam is 0.0002 photons/sq cm per sec. These new limits from SMM can be reconciled with the HEAO 3 results only if SS 433 emits gamma radiation at or above the SMM sensitivity limit on rare occasions due to variable physical conditions in the system.

  17. Determination of the disintegration rate and gamma emission probabilities per decay of 182 Ta

    International Nuclear Information System (INIS)

    Silva, Eliezer Antonio da

    2008-01-01

    In this work the procedure developed for the standardization of 182 Ta sources produced by irradiation at the IPEN IEA-R1 research reactor is presented. The 182 Ta decays with a half-life of 114 days by β - emission, populating the excited levels of 182 W. It emits gamma rays with several energies mainly between 31 keV and 264 keV and between 1001 keV and 1453 keV. The measurements were performed in a 4πβ-γ coincidence system by using the extrapolation technique. The coincidence system is composed of a 4 π proportional counter coupled to a NaI(Tl) cristal. The measurements were undertaken selecting two windows in the γ-channel, in order to check the consistency of the results. A Monte Carlo calculation was performed in order to predict the behavior of the observed activity as a function of 4πβ the detector efficiency and the results were compared to experimental values. The most intense gamma-ray emission probabilities of 182 Ta were determined by means of an HPGe gamma spectrometer, the germanium efficiency curve was obtained by using sources 152 Eu, 241 Am, 60 Co, 133 Ba and 166m Ho standardized in a primary system. The uncertainties involved in the measurements were treated by the covariance methodology. The results obtained are in good agreement with the experimental uncertainty compared with literature values. (author)

  18. Environmental gamma radiation measurement in District Swat (Pakistan))

    International Nuclear Information System (INIS)

    Jabbar, T.; Khan, K.; Akhter, P.; Jabbar, A.; Subhani, M.S.

    2008-01-01

    External exposure to environmental gamma ray sources is an important component of exposure to the public. A survey was carried out to determine activity concentration levels and associated doses from 226 Ra, 232 Th, 40 K and 137 Cs by means of high-resolution gamma ray spectrometry in the Swat district, famous for tourism. The mean concentrations for 226 Ra, 232 Th and 40 K were found to be 50.4 ± 0.7, 34.8 ± 0.7 and 434.5 ± 7.4 Bq kg -1 , respectively, in soil samples, which are slightly more than the world average values. However, 137 Cs was only found in the soil sample of Barikot with an activity concentration of 34 ± 1.2 Bq kg -1 . Only 40 K was determined in vegetation samples with an average activity of 172.2 ± 1.7 Bq kg -1 , whereas in water samples, all radionuclides were found below lower limits of detection. The radium equivalent activity in all soil samples is lower than the limit set in the Organisation for Economic Cooperation and Development report (370 Bq kg -1 ). The value of the external exposure dose has been determined from the content of these radionuclides in soil. The average terrestrial gamma air absorbed dose rate was observed to be 62.4 nGy h -1 , which yields an annual effective dose of 0.08 mSv. The average value of the annual effective dose lies close to the global range of outdoor radiation exposure given in United Nations Scientific Committee on the Effects of Atomic Radiation. However, the main component of the radiation dose to the population residing in the study area arises from cosmic ray due to high altitude. (authors)

  19. Emission spectra of alkali-metal (K,Na,Li)-He exciplexes in cold helium gas

    International Nuclear Information System (INIS)

    Enomoto, K.; Hirano, K.; Kumakura, M.; Takahashi, Y.; Yabuzaki, T.

    2004-01-01

    We have observed emission spectra of excimers and exciplexes composed of a light alkali-metal atom in the first excited state and 4 He atoms [K*He n (n=1-6), Na * He n (n=1-4), and Li * He n (n=1,2)] in cryogenic He gas (the temperature 2 K -1 . Differently from exciplexes with heavier alkali-metal atoms, the spectra for the different number of He atoms were well separated, so that their assignment could be made experimentally. Comparing with the spectra of K * He n , we found that the infrared emission spectrum of the K atom excited in liquid He was from K*He 6 . To confirm the assignment, we have also carried out ab initio calculation of adiabatic potential curves and peak positions of the emission spectra of the exciplexes

  20. Amplitude analysis of $D^0\\rightarrow K^+K^-\\pi^+\\pi^-$ and its subsequent use in measuring the CKM phase $\\gamma$ through $B^{\\pm}\\rightarrow D(\\rightarrow K^+K^-\\pi^+\\pi^-)K^{\\pm}$ decays at LHCb

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00392618

    An amplitude analysis of the 4-body charmed decay $D^0\\rightarrow K^+K^-\\pi^+\\pi^-$ has been performed using data collected from symmetric electron-positron collisions at the CLEO experiment. Both flavour tagged and CP tagged data are utilised in the analysis, making it unique among amplitude analyses performed at other experiments and providing extra sensitivity to the phases of the amplitude components. This analysis uses a data driven regularisation method to determine which of the multitude of possible amplitude components to include in the amplitude model. The dominant contributions are found to be $D^0 \\to \\phi(1020) \\, \\rho^0(770)$, $D^0 \\to K^- \\, K_{1}(1270)^{+}$ and $D^0 \\to K^- \\, K_{1}(1400)^{+}$. Tests for CP violation in the $D$ system are performed using the amplitude model; no evidence for CP violation is found. The amplitude model obtained is crucial input for a model-dependent measurement of the CP-violating phase $\\gamma$ using $B^\\pm \\to D(\\to K^+K^-\\pi^+\\pi^-)K^\\pm$ decays, which remains...

  1. 40 CFR 52.2086 - Emission inventories.

    Science.gov (United States)

    2010-07-01

    ... area is classified as serious and includes the entire state of Rhode Island. (d) Minor revisions to the... inventory for the Providence ozone nonattainment area on January 12, 1993 as a revision to the State... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Emission inventories. 52.2086 Section...

  2. New stage in high-energy gamma-ray studies with GAMMA-400 after Fermi-LAT

    Directory of Open Access Journals (Sweden)

    Topchiev N.P.

    2017-01-01

    Full Text Available Fermi-LAT has made a significant contribution to the study of high-energy gamma-ray diffuse emission and the observations of 3000 discrete sources. However, one third of all gamma-ray sources (both galactic and extragalactic are unidentified, the data on the diffuse gamma-ray emission should be clarified, and signatures of dark matter particles in the high-energy gamma-ray range are not observed up to now. GAMMA-400, the currently developing gamma-ray telescope, will have angular (∼0.01∘ at 100 GeV and energy (∼1% at 100 GeV resolutions in the energy range of 10–1000 GeV which are better than Fermi-LAT (as well as ground gamma-ray telescopes by a factor of 5–10. It will observe some regions of the Universe (such as the Galactic Center, Fermi Bubbles, Crab, Cygnus, etc. in a highly elliptic orbit (without shading the telescope by the Earth continuously for a long time. It will allow us to identify many discrete sources, to clarify the structure of extended sources, to specify the data on the diffuse emission, and to resolve gamma rays from dark matter particles.

  3. Constraints on light WIMP candidates from the isotropic diffuse gamma-ray emission

    International Nuclear Information System (INIS)

    Arina, Chiara; Tytgat, Michel H.G.

    2011-01-01

    Motivated by the measurements reported by direct detection experiments, most notably DAMA, CDMS-II, CoGeNT and Xenon10/100, we study further the constraints that might be set on some light dark matter candidates, M DM ∼ few GeV, using the Fermi-LAT data on the isotropic gamma-ray diffuse emission. In particular, we consider a Dirac fermion singlet interacting through a new Z' gauge boson, and a scalar singlet S interacting through the Higgs portal. Both candidates are WIMP (Weakly Interacting Massive Particles), i.e. they have an annihilation cross-section in the pbarn range. Also they may both have a spin-independent elastic cross section on nucleons in the range required by direct detection experiments. Although being generic WIMP candidates, because they have different interactions with Standard Model particles, their phenomenology regarding the isotropic diffuse gamma-ray emission is quite distinct. In the case of the scalar singlet, the one-to-one correspondence between its annihilation cross-section and its spin-independent elastic scattering cross-section permits to express the constraints from the Fermi-LAT data in the direct detection exclusion plot, σ n 0 −M DM . Depending on the astrophysics, we argue that it is possible to exclude the singlet scalar dark matter candidate at 95% confidence level. The constraints on the Dirac singlet interacting through a Z' are comparatively weaker

  4. Multifrequency Observations of Gamma-Ray Burst

    OpenAIRE

    Greiner, J.

    1995-01-01

    Neither a flaring nor a quiescent counterpart to a gamma-ray burst has yet been convincingly identified at any wavelength region. The present status of the search for counterparts of classical gamma-ray bursts is given. Particular emphasis is put on the search for flaring counterparts, i.e. emission during or shortly after the gamma-ray emission.

  5. Recombining Plasma and Gamma-Ray Emission in the Mixed-morphology Supernova Remnant 3C 400.2

    Energy Technology Data Exchange (ETDEWEB)

    Ergin, T. [TUBITAK Space Technologies Research Institute, ODTU Campus, 06800, Ankara (Turkey); Sezer, A. [Department of Electrical-Electronics Engineering, Avrasya University, 61250 Trabzon (Turkey); Sano, H.; Fukui, Y. [Department of Physics, Nagoya University, Chikusa-ku, Nagoya, Aichi 464–8601 (Japan); Yamazaki, R., E-mail: ergin.tulun@gmail.com, E-mail: aytap.sezer@avrasya.edu.tr, E-mail: sano@a.phys.nagoya-u.ac.jp [Department of Physics and Mathematics, Aoyama Gakuin University, 5-10-1 Fuchinobe, Sagamihara 252–5258 (Japan)

    2017-06-10

    3C 400.2 belongs to the mixed-morphology supernova remnant class, showing center-filled X-ray and shell-like radio morphology. We present a study of 3C 400.2 with archival Suzaku and Fermi -LAT observations. We find recombining plasma (RP) in the Suzaku spectra of north–east and south–east regions. The spectra of these regions are well described by two-component thermal plasma models: the hard component is in RP, while the soft component is in collisional ionization equilibrium (CIE) conditions. The RP has enhanced abundances, indicating that the X-ray emission has an ejecta origin, while the CIE has solar abundances associated with the interstellar material. The X-ray spectra of north–west and south–west regions are best fitted by a two-component thermal plasma model: an ionizing and a CIE plasma. We have detected GeV gamma-ray emission from 3C 400.2 at the level of ∼5 σ , assuming a point-like source model with a power-law (PL) type spectrum. We have also detected a new GeV source at the level of ∼13 σ, assuming a Gaussian extension model with a PL-type spectrum in the neighborhood of the supernova remnant. We report the analysis results of 3C 400.2 and the new extended gamma-ray source, and discuss the nature of gamma-ray emission of 3C 400.2 in the context of existing NANTEN CO data, Dominion Radio Astrophysical Observatory H i data, and the Suzaku X-ray analysis results.

  6. Temperature dependence of the soft-x-ray emission edges of simple metals

    International Nuclear Information System (INIS)

    Tagle, J.A.; Arakawa, E.T.; Callcott, T.A.

    1980-01-01

    The widths and energy positions of the M/sub 2,3/-emission edge of potassium, K-emission edge of beryllium, and L/sub 2,3/-emission edges of aluminum and magnesium have been measured for temperatures between 80 and 600 0 K. All band edges broaden (ΔGAMMA) and shift in energy (ΔE) with increasing temperatures for these materials. Similar results were reported earlier for the Li K-emission edge and Na L/sub 2,3/ edge. Lattice-relaxation processes and the phonon core-hole interaction are the dominant mechanisms affecting the core-level widths and the experimentally observed edge widths. The edge shifts are found to be proportional to the thermal expansion of the lattice, and are discussed in terms of the electron energy-level shifts which occur as the lattice dilates

  7. Measuring 137Cs, 40K and decay products of 226Ra and 232Th in samples of different nature by a multidetector spectrometer

    International Nuclear Information System (INIS)

    Antovic, N.M.; Popovic, V.; Vukotic, P.

    2011-01-01

    A coincidence method for measuring 137 Cs, 40 K, 226 Ra and 232 Th decay products activity in soil, vegetation and fish samples, was applied to the six-crystal gamma-coincidence spectrometer PRIPYAT-2M. In this way, some problems appeared in simultaneous measurement of 137 Cs, 226 Ra and 232 Th by NaI(Tl) detectors and the PRIPYAT-2M spectrometer were solved. The obtained results were agreeable with the HPGe spectrometer ones. (author)

  8. Investigation of PBAT dosimetric properties for high gamma dose dosimetry

    International Nuclear Information System (INIS)

    Cunha, Elisete L.; Schimitberger, Thiago

    2017-01-01

    Poly(butylene adipate-co-terephthalate) (PBAT) is an aliphatic-aromatic copolyester which is biodegradable. It is a non-photoluminescent copolyester that becomes photoluminescent after previous exposure to gamma doses higher than 100 kGy. After the previous high energy irradiation, the material shows the highest photo-stimulated luminescence emission when excited with a LED source at wavelengths ranging from 370 to 405 nm. In this work we investigated the enhancement of the photoluminescence (PL) and dosimetric properties of PBAT, after exposure to high doses of gamma radiation ranging from 50 to 4,000 kGy. In this investigation we demonstrate that increasing the PBAT film thickness by 100 μm enhances the PL output by 3.5 times, when irradiated with 500 kGy. Also, besides the already known color green brightness, the PL intensity can also be used for high dose dosimetry purposes for doses ranging from 50 to 750 kGy. The FTIR analysis has demonstrated that the there is a linear relationship between peak intensity and dose for doses ranging from 100 and 2,000 kGy for the absorbance peaks at 3,241 cm -1 and 3271 cm -1 , with linear correlation coefficients of 0.9981 and 0.9992, respectively. The results indicate that PBAT has great potential for applications in bio-imaging devices and high gamma dose dosimetry. (author)

  9. Investigation of PBAT dosimetric properties for high gamma dose dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Elisete L.; Schimitberger, Thiago, E-mail: elisete.cunha@cdtn.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Oliveira, Cristiana M.; Faria, Luiz O., E-mail: farialo@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    Poly(butylene adipate-co-terephthalate) (PBAT) is an aliphatic-aromatic copolyester which is biodegradable. It is a non-photoluminescent copolyester that becomes photoluminescent after previous exposure to gamma doses higher than 100 kGy. After the previous high energy irradiation, the material shows the highest photo-stimulated luminescence emission when excited with a LED source at wavelengths ranging from 370 to 405 nm. In this work we investigated the enhancement of the photoluminescence (PL) and dosimetric properties of PBAT, after exposure to high doses of gamma radiation ranging from 50 to 4,000 kGy. In this investigation we demonstrate that increasing the PBAT film thickness by 100 μm enhances the PL output by 3.5 times, when irradiated with 500 kGy. Also, besides the already known color green brightness, the PL intensity can also be used for high dose dosimetry purposes for doses ranging from 50 to 750 kGy. The FTIR analysis has demonstrated that the there is a linear relationship between peak intensity and dose for doses ranging from 100 and 2,000 kGy for the absorbance peaks at 3,241 cm{sup -1} and 3271 cm{sup -1}, with linear correlation coefficients of 0.9981 and 0.9992, respectively. The results indicate that PBAT has great potential for applications in bio-imaging devices and high gamma dose dosimetry. (author)

  10. 40 CFR 86.1828-01 - Emission data vehicle selection.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Emission data vehicle selection. 86... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light...

  11. 40 CFR 86.1828-10 - Emission data vehicle selection.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Emission data vehicle selection. 86... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light...

  12. Induction of mutation, through gamma rays, in sugarcane

    International Nuclear Information System (INIS)

    Vieira, M.A.S.; Matsuoka, S.; Ruschel, R.

    1984-01-01

    Variety buds Co-740 of sugar cane were irradiated with gamma rays 60 Co at 0.0, 3.0, 4.0, 5.0, 6.0 and 7.0 kR to study changes in the obtained progeny. Evaluation of the germination capacity, height of plants and morphological changes were studied in the different treatments. (M.A.C.) [pt

  13. Environmental gamma background measurements in China Jinping Underground Laboratory

    International Nuclear Information System (INIS)

    Zhi Zeng; Jian Su; Hao Ma; Hengguan Yi; Jianping Cheng; Qian Yue; Junli Li; Hui Zhang

    2014-01-01

    To determine the environmental gamma background levels which affects rare events experiments, we measured in situ gamma spectrum at four locations in the China Jinping Underground Laboratory. The integral background count rates (40-2,700 keV) varied from 3.76 to 74.1 cps. The average count rate of the measurements inside the CJPL was 73.4 cps. The spectrometer was calibrated with a 152 Eu point source and Monte Carlo simulation to obtain the activity conversion factors for the rock and the air, respectively. The rocks that surrounded the CJPL was characterized by very low activity concentrations of 238 U (3.69-4.21 Bq kg -1 ), 232 Th (0.52-0.64 Bq kg -1 ) and 40 K (4.28 Bq kg -1 ). (author)

  14. GAMMA RAYS FROM STAR FORMATION IN CLUSTERS OF GALAXIES

    International Nuclear Information System (INIS)

    Storm, Emma M.; Jeltema, Tesla E.; Profumo, Stefano

    2012-01-01

    Star formation in galaxies is observed to be associated with gamma-ray emission, presumably from non-thermal processes connected to the acceleration of cosmic-ray nuclei and electrons. The detection of gamma rays from starburst galaxies by the Fermi Large Area Telescope (LAT) has allowed the determination of a functional relationship between star formation rate and gamma-ray luminosity. Since star formation is known to scale with total infrared (8-1000 μm) and radio (1.4 GHz) luminosity, the observed infrared and radio emission from a star-forming galaxy can be used to quantitatively infer the galaxy's gamma-ray luminosity. Similarly, star-forming galaxies within galaxy clusters allow us to derive lower limits on the gamma-ray emission from clusters, which have not yet been conclusively detected in gamma rays. In this study, we apply the functional relationships between gamma-ray luminosity and radio and IR luminosities of galaxies derived by the Fermi Collaboration to a sample of the best candidate galaxy clusters for detection in gamma rays in order to place lower limits on the gamma-ray emission associated with star formation in galaxy clusters. We find that several clusters have predicted gamma-ray emission from star formation that are within an order of magnitude of the upper limits derived in Ackermann et al. based on non-detection by Fermi-LAT. Given the current gamma-ray limits, star formation likely plays a significant role in the gamma-ray emission in some clusters, especially those with cool cores. We predict that both Fermi-LAT over the course of its lifetime and the future Cerenkov Telescope Array will be able to detect gamma-ray emission from star-forming galaxies in clusters.

  15. Theoretical model of Orion gamma emission: acceleration, propagation and interaction of energetic particles in the interstellar medium

    International Nuclear Information System (INIS)

    Parizot, Etienne

    1997-01-01

    This research thesis reports the development of a general model for the study of the propagation and interaction of energetic particles (cosmic rays, and so on) in the interstellar medium (ISM). The first part addresses the development of theoretical and numerical tools. The author presents cosmic rays and energetic particles, presents and describes the various processes related to high-energy particles (matter ionisation, synchrotron and Bremsstrahlung radiation, Compton scattering, nuclear processes), addresses the transport and acceleration of energetic particles (plasmas, magnetic fields and energetic particles, elements of kinetic theory, transport and acceleration of energetic particles), and describes the general model of production of γ nuclear lines and of secondary nuclei. The second part addresses the gamma signature of a massive star in a dense medium: presentation and description of massive stars and of the circumstellar medium, life, death and gamma resurrection of a massive star at the heart of a cloud. The third part addresses the case of the gamma emission by Orion, and more particularly presents a theoretical model of this emission. Some generalities and perspectives (theoretical as well as observational) are then stated [fr

  16. Measurements of proton induced gamma-ray emission cross sections and yields on Al and Na

    International Nuclear Information System (INIS)

    Chiari, M.

    2014-01-01

    Full text: The measurement of the proton induced gamma-ray emission cross sections on low-Z nuclei such as Na and Al of specific interest for environmental and cultural heritage applications, were carried out for proton beam energy from 2.5 to 4.1 MeV, including the measurement of the angular distributions of the emitted rays at selected angles, i.e. 90°, 45° and 0°, using an array of three HPGe detectors coupled to the multi-purpose scattering chamber on the +30° beamline of the Tandetron accelerator at INFN LABEC. The studied gamma-ray inducing reactions were: "2"7Al(p,p’γ)"2"7Al (gamma-ray energies 844 and 1014 keV), and "2"3Na(p,p"’γ)"2"3Na (gamma-ray energies 441 and 1636 keV) and "2"3Na(p,"αγ)"2"0Ne (gamma-ray energy 1634 keV). As a first step, the absolute efficiency of the HPGe detectors placed at 90° and 0° was improved by a factor up to 2 by designing a new target holder, with less absorbing material facing the HPGe detector at 90°, and installing a new Faraday cup/beam stopper with graphite body instead of stainless steel and a thinner Ta cap at the bottom, to reduce the shielding effect for the HPGe detector at 0°. The measurement of the absolute efficiency of the HPGe detectors of the array was carried out using a "1"5"2Eu calibration source mounted on the target holder and placed in the exact position of the target under irradiation. The proton beam energy was calibrated using an aluminum thick target and the resonances at 991.86 keV and 1683.57 keV, respectively in the (p,γ) and (p,p"’γ) reactions on "2"7Al, and a native aluminium oxide thin target and the resonance at 3470 keV in elastic scattering on "1"6O. The targets employed were thin Al (29 μg/cm"2) and NaF (35 μg/cm"2) films evaporated on thin self-supporting Ag foils; in order to obtain the differential gamma-ray inducing cross-sections, we normalized the results by the Rutherford elastic backscattering of protons from Ag, adopting a procedure not relying on the

  17. Measurement of the CKM angle $\\gamma$ using $B^\\pm \\to D K^\\pm$ with $D \\to K^0_{\\rm S} \\pi^+\\pi^-, K^0_{\\rm S} K^+ K^-$ decays

    CERN Document Server

    Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassen, Rolf; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Belogurov, Sergey; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Bizzeti, Andrea; Bjørnstad, Pål Marius; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borgia, Alessandra; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Brambach, Tobias; van den Brand, Johannes; Bressieux, Joël; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Brown, Henry; Bursche, Albert; Busetto, Giovanni; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Ciba, Krzystof; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cojocariu, Lucian; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Counts, Ian; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pascal; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Di Canto, Angelo; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gaspar, Clara; Gauld, Rhorry; Gavardi, Laura; Gavrilov, Gennadii; Geraci, Angelo; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Giani', Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, V.V.; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Hampson, Thomas; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Hunt, Philip; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jaton, Pierre; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kaballo, Michael; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kozlinskiy, Alexandr; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leo, Sabato; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lopez-March, Neus; Lowdon, Peter; Lu, Haiting; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Machikhiliyan, Irina V; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martens, Aurelien; Martín Sánchez, Alexandra; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathe, Zoltan; Matteuzzi, Clara; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; McSkelly, Ben; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Moggi, Niccolò; Molina Rodriguez, Josue; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Katharina; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Nicol, Michelle; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Oggero, Serena; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Orlandea, Marius; Otalora Goicochea, Juan Martin; Owen, Patrick; Oyanguren, Maria Arantza; Pal, Bilas Kanti; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parkes, Christopher; Parkinson, Christopher John; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pazos Alvarez, Antonio; Pearce, Alex; Pellegrino, Antonio; Pepe Altarelli, Monica; Perazzini, Stefano; Perez Trigo, Eliseo; Perret, Pascal; Perrin-Terrin, Mathieu; Pescatore, Luca; Pesen, Erhan; Petridis, Konstantin; Petrolini, Alessandro; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Polci, Francesco; Poluektov, Anton; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Roa Romero, Diego; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz, Hugo; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrie, Mauro; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Seco, Marcos; Semennikov, Alexander; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skwarnicki, Tomasz; Smith, Anthony; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Sparkes, Ailsa; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Subbiah, Vijay Kartik; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szilard, Daniela; Szumlak, Tomasz; T'Jampens, Stephane; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Tran, Minh Tâm; Tresch, Marco; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ubeda Garcia, Mario; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; Voss, Helge; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Whitehead, Mark; Wicht, Jean; Wiedner, Dirk; Wilkinson, Guy; Williams, Matthew; Williams, Mike; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wu, Suzhi; Wyllie, Kenneth; Xie, Yuehong; Xing, Zhou; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Wen Chao; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang; Zvyagin, Alexander

    2014-10-16

    A binned Dalitz plot analysis of $B^\\pm \\to D K^\\pm$ decays, with $D \\to K^0_{\\rm S} \\pi^+\\pi^-$ and $D \\to K^0_{\\rm S} K^+ K^-$, is performed to measure the $C\\!P$-violating observables $x_{\\pm}$ and $y_{\\pm}$, which are sensitive to the Cabibbo-Kobayashi-Maskawa angle $\\gamma$. The analysis exploits a sample of proton-proton collision data corresponding to 3.0 fb$^{-1}$ collected by the LHCb experiment. Measurements from CLEO-c of the variation of the strong-interaction phase of the $D$ decay over the Dalitz plot are used as inputs. The values of the parameters are found to be $x_+ = ( -7.7 \\pm 2.4 \\pm 1.0 \\pm 0.4 )\\times 10^{-2}$, $x_- = (2.5 \\pm 2.5 \\pm 1.0 \\pm 0.5) \\times 10^{-2}$, $y_+ = (-2.2 \\pm 2.5 \\pm 0.4 \\pm 1.0)\\times 10^{-2}$, and $y_- = (7.5 \\pm 2.9 \\pm 0.5 \\pm 1.4) \\times 10^{-2}$. The first, second, and third uncertainties are the statistical, the experimental systematic, and that associated with the precision of the strong-phase parameters. These are the most precise measurements of these obs...

  18. STUDY CONCERNING THE POSSIBILITY OF GAMMA-SPECTROSCOPY METHOD TO DETERMINE THE TOTAL POTASSIUM IN SOILS

    Directory of Open Access Journals (Sweden)

    Tamara Leah

    2011-12-01

    Full Text Available It was proved the possibility of determination the total potassium in soils by gamma-spectroscopic method with subsequent calculation of total potassium content in according to value of 40K isotope (expressed in Becquerel, Bq, using the formula: К2О, % = С . А, where: C – conversion coefficient, A – activity of isotope 40K in soil, Bq/kg. Conversion coefficient for chernozems of Moldova – C=0,00337.

  19. Initial search for triggered gamma emission from Hf-178(m2) using the YSU miniball array

    Czech Academy of Sciences Publication Activity Database

    Carroll, J. J.; Burnett, J.; Drummond, T.; Lepak, J.; Propri, R.; Smith, D.; Karamian, S. A.; Adam, Jindřich; Stedile, F.; Agee, FJ.

    2002-01-01

    Roč. 143, 1, 2, 3, 4 (2002), s. 37-54 ISSN 0304-3843 Institutional research plan: CEZ:AV0Z1048901 Keywords : triggered gamma emission * Hf-178(m2) * nuclear batteries Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.533, year: 2002

  20. Stacked search for time shifted high energy neutrinos from gamma ray bursts with the Antares neutrino telescope

    Energy Technology Data Exchange (ETDEWEB)

    Adrian-Martinez, S.; Ardid, M.; Felis, I.; Martinez-Mora, J.A.; Saldana, M. [Universitat Politecnica de Valencia, Institut d' Investigacio per a la Gestio Integrada de les Zones Costaneres (IGIC), Gandia (Spain); Albert, A.; Drouhin, D.; Racca, C. [GRPHE-Institut Universitaire de Technologie de Colmar, 34 rue du Grillenbreit, BP 50568, Colmar (France); Andre, M. [Technical University of Catalonia, Laboratory of Applied Bioacoustics, Vilanova i la Geltru, Barcelona (Spain); Anghinolfi, M. [INFN-Sezione di Genova, Genoa (Italy); Anton, G.; Eberl, T.; Enzenhoefer, A.; Fehn, K.; Folger, F.; Geisselsoeder, S.; Geyer, K.; Gleixner, A.; Graf, K.; Hallmann, S.; Hoessl, J.; Hofestaedt, J.; James, C.W.; Kalekin, O.; Katz, U.; Kiessling, D.; Lahmann, R.; Richter, R.; Roensch, K.; Schmid, J.; Schnabel, J.; Seitz, T.; Sieger, C.; Tselengidou, M.; Wagner, S. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Erlangen Centre for Astroparticle Physics, Erlangen (Germany); Aubert, J.J.; Bertin, V.; Brunner, J.; Busto, J.; Carr, J.; Costantini, H.; Coyle, P.; Dornic, D.; Mathieu, A.; Vallee, C. [CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France); Baret, B.; Barrios-Marti, J.; Hernandez-Rey, J.J.; Sanchez-Losa, A.; Toennis, C.; Zornoza, J.D.; Zuniga, J. [CSIC-Universitat de Valencia, IFIC-Instituto de Fisica Corpuscular, Edificios Investigacion de Paterna, Paterna, Valencia (Spain); Basa, S.; Marcelin, M.; Nezri, E. [Pole de l' Etoile Site de Chateau-Gombert, LAM-Laboratoire d' Astrophysique de Marseille, Marseille Cedex 13 (France); Biagi, S.; Coniglione, R.; Distefano, C.; Piattelli, P.; Riccobene, G.; Sapienza, P.; Trovato, A. [INFN-Laboratori Nazionali del Sud (LNS), Catania (Italy); Bormuth, R.; Jong, M. de; Samtleben, D.F.E. [Nikhef, Science Park, Amsterdam (Netherlands); Universiteit Leiden, Leids Instituut voor Onderzoek in Natuurkunde, Leiden (Netherlands); Bouwhuis, M.C.; Heijboer, A.J.; Michael, T.; Steijger, J.J.M.; Visser, E. [Nikhef, Science Park, Amsterdam (Netherlands); Bruijn, R. [Nikhef, Science Park, Amsterdam (Netherlands); Universiteit van Amsterdam, Instituut voor Hoge-Energie Fysica, Amsterdam (Netherlands); Capone, A.; De Bonis, G.; Fermani, P.; Perrina, C. [INFN-Sezione di Roma, Rome (Italy); Dipartimento di Fisica dell' Universita La Sapienza, Rome (Italy); Caramete, L.; Pavalas, G.E.; Popa, V. [Institute for Space Sciences, Bucharest, Magurele (Romania); Chiarusi, T. [INFN-Sezione di Bologna, Bologna (Italy); Circella, M. [INFN-Sezione di Bari, Bari (Italy); Creusot, A.; Galata, S.; Gracia-Ruiz, R.; Van Elewyck, V. [APC, Universite Paris Diderot, CNRS/IN2P3, CEA/IRFU, Observatoire de Paris, Sorbonne Paris Cite, Paris (France); Dekeyser, I.; Lefevre, D.; Tamburini, C. [Aix-Marseille University, Mediterranean Institute of Oceanography (MIO), Marseille Cedex 9 (France); Universite du Sud Toulon-Var, CNRS-INSU/IRD UM 110, La Garde Cedex (France); Deschamps, A.; Hello, Y. [Geoazur, Universite Nice Sophia-Antipolis, CNRS/INSU, IRD, Observatoire de la Cote d' Azur, Sophia Antipolis (France); Donzaud, C. [APC, Universite Paris Diderot, CNRS/IN2P3, CEA/IRFU, Observatoire de Paris, Sorbonne Paris Cite, Paris (France); Universite Paris-Sud, Orsay Cedex (France); Dumas, A.; Gay, P. [Clermont Universite, Universite Blaise Pascal, CNRS/IN2P3, Laboratoire de Physique Corpusculaire, BP 10448, Clermont-Ferrand (France); Elsaesser, D.; Kadler, M.; Kreter, M.; Mueller, C. [Universitaet Wuerzburg, Institut fuer Theoretische Physik und Astrophysik, Wuerzburg (Germany); Fusco, L.A.; Margiotta, A.; Pellegrino, C.; Spurio, M. [INFN-Sezione di Bologna, Bologna (Italy); Dipartimento di Fisica dell' Universita, Bologna (Italy); Giordano, V. [INFN-Sezione di Catania, Catania (Italy); Haren, H. van [Royal Netherlands Institute for Sea Research (NIOZ), ' t Horntje, Texel (Netherlands); Hugon, C.; Taiuti, M. [INFN-Sezione di Genova, Genoa (Italy); Dipartimento di Fisica dell' Universita, Genoa (Italy); Kooijman, P. [Nikhef, Science Park, Amsterdam (Netherlands); Universiteit Utrecht, Faculteit Betawetenschappen, Utrecht (Netherlands); Universiteit van Amsterdam, Instituut voor Hoge-Energie Fysica, Amsterdam (Netherlands); Kouchner, A. [APC, Universite Paris Diderot, CNRS/IN2P3, CEA/IRFU, Observatoire de Paris, Sorbonne Paris Cite, Paris (France); Institut Universitaire de France, Paris (France); Kreykenbohm, I.; Wilms, J. [Universitaet Erlangen-Nuernberg, Dr. Remeis-Sternwarte and ECAP, Bamberg (Germany); Kulikovskiy, V. [INFN-Laboratori Nazionali del Sud (LNS), Catania (Italy); Moscow State University, Skobeltsyn Institute of Nuclear Physics, Moscow (Russian Federation); Leonora, E. [INFN-Sezione di Catania, Catania (Italy); Dipartimento di Fisica ed Astronomia dell' Universita, Catania (Italy); Loucatos, S. [APC, Universite Paris Diderot, CNRS/IN2P3, CEA/IRFU, Observatoire de Paris, Sorbonne Paris Cite, Paris (France); CEA Saclay, Direction des Sciences de la Matiere, Institut de recherche sur les lois fondamentales de l' Univers, Service de Physique des Particules, Gif-sur-Yvette Cedex (France); Marinelli, A. [INFN-Sezione di Pisa, Pisa (Italy); Dipartimento di Fisica dell' Universita, Pisa (Italy); Migliozzi, P. [INFN-Sezione di Napoli, Naples (IT); Moussa, A. [University Mohammed I, Laboratory of Physics of Matter and Radiations, Oujda (MA); Pradier, T. [Universite de Strasbourg et CNRS/IN2P3, IPHC-Institut Pluridisciplinaire Hubert Curien, 23 rue du Loess, BP 28, Strasbourg Cedex 2 (FR); Sanguineti, M. [Dipartimento di Fisica dell' Universita, Genoa (IT); Schuessler, F.; Stolarczyk, T.; Vallage, B. [CEA Saclay, Direction des Sciences de la Matiere, Institut de recherche sur les lois fondamentales de l' Univers, Service de Physique des Particules, Gif-sur-Yvette Cedex (FR); Vivolo, D. [INFN-Sezione di Napoli, Naples (IT); Dipartimento di Fisica dell' Universita Federico II di Napoli, Naples (IT)

    2017-01-15

    A search for high-energy neutrino emission correlated with gamma-ray bursts outside the electromagnetic prompt-emission time window is presented. Using a stacking approach of the time delays between reported gamma-ray burst alerts and spatially coincident muon-neutrino signatures, data from the Antares neutrino telescope recorded between 2007 and 2012 are analysed. One year of public data from the IceCube detector between 2008 and 2009 have been also investigated. The respective timing profiles are scanned for statistically significant accumulations within 40 days of the Gamma Ray Burst, as expected from Lorentz Invariance Violation effects and some astrophysical models. No significant excess over the expected accidental coincidence rate could be found in either of the two data sets. The average strength of the neutrino signal is found to be fainter than one detectable neutrino signal per hundred gamma-ray bursts in the Antares data at 90% confidence level. (orig.)

  1. Stacked search for time shifted high energy neutrinos from gamma ray bursts with the Antares neutrino telescope

    International Nuclear Information System (INIS)

    Adrian-Martinez, S.; Ardid, M.; Felis, I.; Martinez-Mora, J.A.; Saldana, M.; Albert, A.; Drouhin, D.; Racca, C.; Andre, M.; Anghinolfi, M.; Anton, G.; Eberl, T.; Enzenhoefer, A.; Fehn, K.; Folger, F.; Geisselsoeder, S.; Geyer, K.; Gleixner, A.; Graf, K.; Hallmann, S.; Hoessl, J.; Hofestaedt, J.; James, C.W.; Kalekin, O.; Katz, U.; Kiessling, D.; Lahmann, R.; Richter, R.; Roensch, K.; Schmid, J.; Schnabel, J.; Seitz, T.; Sieger, C.; Tselengidou, M.; Wagner, S.; Aubert, J.J.; Bertin, V.; Brunner, J.; Busto, J.; Carr, J.; Costantini, H.; Coyle, P.; Dornic, D.; Mathieu, A.; Vallee, C.; Baret, B.; Barrios-Marti, J.; Hernandez-Rey, J.J.; Sanchez-Losa, A.; Toennis, C.; Zornoza, J.D.; Zuniga, J.; Basa, S.; Marcelin, M.; Nezri, E.; Biagi, S.; Coniglione, R.; Distefano, C.; Piattelli, P.; Riccobene, G.; Sapienza, P.; Trovato, A.; Bormuth, R.; Jong, M. de; Samtleben, D.F.E.; Bouwhuis, M.C.; Heijboer, A.J.; Michael, T.; Steijger, J.J.M.; Visser, E.; Bruijn, R.; Capone, A.; De Bonis, G.; Fermani, P.; Perrina, C.; Caramete, L.; Pavalas, G.E.; Popa, V.; Chiarusi, T.; Circella, M.; Creusot, A.; Galata, S.; Gracia-Ruiz, R.; Van Elewyck, V.; Dekeyser, I.; Lefevre, D.; Tamburini, C.; Deschamps, A.; Hello, Y.; Donzaud, C.; Dumas, A.; Gay, P.; Elsaesser, D.; Kadler, M.; Kreter, M.; Mueller, C.; Fusco, L.A.; Margiotta, A.; Pellegrino, C.; Spurio, M.; Giordano, V.; Haren, H. van; Hugon, C.; Taiuti, M.; Kooijman, P.; Kouchner, A.; Kreykenbohm, I.; Wilms, J.; Kulikovskiy, V.; Leonora, E.; Loucatos, S.; Marinelli, A.; Migliozzi, P.; Moussa, A.; Pradier, T.; Sanguineti, M.; Schuessler, F.; Stolarczyk, T.; Vallage, B.; Vivolo, D.

    2017-01-01

    A search for high-energy neutrino emission correlated with gamma-ray bursts outside the electromagnetic prompt-emission time window is presented. Using a stacking approach of the time delays between reported gamma-ray burst alerts and spatially coincident muon-neutrino signatures, data from the Antares neutrino telescope recorded between 2007 and 2012 are analysed. One year of public data from the IceCube detector between 2008 and 2009 have been also investigated. The respective timing profiles are scanned for statistically significant accumulations within 40 days of the Gamma Ray Burst, as expected from Lorentz Invariance Violation effects and some astrophysical models. No significant excess over the expected accidental coincidence rate could be found in either of the two data sets. The average strength of the neutrino signal is found to be fainter than one detectable neutrino signal per hundred gamma-ray bursts in the Antares data at 90% confidence level. (orig.)

  2. Photon polarization in $B_s^0 \\to \\phi \\gamma$ decays at the LHCb experiment

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00392538; Martínez Vidal, Fernando

    The Standard Model predicts a predominance of left handed photons emitted in the $b \\to s\\gamma$ interaction, due to the coupling of the $W$ boson to only left handed quarks. Moreso, several Beyond Standard Model theories predict an enhancement of right handed photon emission. A measurement of the photon polairization is therefore a direct probe of New Physics. The photon polarization sensible parameter $\\mathcal{A}^\\Delta$ is measured through a fit to the ratio of untagged time dependent decay rates of $B_s^0 \\to \\phi \\gamma$ over that of $B^0 \\to K^\\ast \\gamma$, the former being sensitive to the parameter because of its non-negligible decay width difference (Phys.Lett.B664:174-179,2008) and the latter being the control channel due to its kinematical similarities and sixfold larger yield. Using 3 fb$^{-1}$ of data collected at LHCb during 2011 and 2012 at centre of mass energies of 7 and 8 TeV, respectively, 4200 $B_s^0 \\to \\phi \\gamma$ and 25700 $B^0 \\to K^\\ast \\gamma$ events are reconstructed. The selecti...

  3. 40 CFR 98.413 - Calculating GHG emissions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Calculating GHG emissions. 98.413 Section 98.413 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Suppliers of Industrial Greenhouse Gases § 98.413 Calculating...

  4. Radio Observations of Gamma-ray Novae

    Science.gov (United States)

    Linford, Justin D.; Chomiuk, L.; Ribeiro, V.; project, E.-Nova

    2014-01-01

    Recent detection of gamma-ray emission from classical novae by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope surprised many in the astronomical community. We present results from radio observations, obtained using the Karl G. Jansky Very Large Array (VLA), of three gamma-ray novae: Mon2012, Sco2012, and Del2013. Radio observations allow for the calculation of ejecta masses, place limits on the distances, and provide information about the gamma-ray emission mechanism for these sources.

  5. Search for Gamma-Ray Emission from DES Dwarf Spheroidal Galaxy Candidates with Fermi-LAT Data

    Energy Technology Data Exchange (ETDEWEB)

    Drlica-Wagner, A.; et al.

    2015-08-04

    Due to their proximity, high dark-matter (DM) content, and apparent absence of non-thermal processes, Milky Way dwarf spheroidal satellite galaxies (dSphs) are excellent targets for the indirect detection of DM. Recently, eight new dSph candidates were discovered using the first year of data from the Dark Energy Survey (DES). We searched for gamma-ray emission coincident with the positions of these new objects in six years of Fermi Large Area Telescope data. We found no significant excesses of gamma-ray emission. Under the assumption that the DES candidates are dSphs with DM halo properties similar to the known dSphs, we computed individual and combined limits on the velocity-averaged DM annihilation cross section for these new targets. If the estimated DM content of these dSph candidates is confirmed, they will constrain the annihilation cross section to lie below the thermal relic cross section for DM particles with masses $\\lesssim 20\\,\\mathrm{GeV}$ annihilating via the $b\\bar{b}$ or τ(+)τ(-) channels.

  6. 40K in the Black Sea: a proxy to estimate biogenic sedimentation

    International Nuclear Information System (INIS)

    Gulin, S.B.; Gulina, L.V.; Sidorov, I.G.; Proskurnin, V.Yu.; Duka, M.S.; Moseichenko, I.N.; Rodina, E.A.

    2014-01-01

    An approach to estimate the rate of biogenic sedimentation in the Black Sea using the naturally occurring radionuclide 40 K has been considered. It allows assessment of the contribution of suspended matter of biological origin to the overall sediment accumulation in the Black Sea coastal, shelf and deep-water areas. Based upon this method, a relationship between the biogenic fraction of the seabed sediments and the water depth has been established with a view to differentiating the contributions of allochthonous and autochthonous suspended matter to the sedimentation rate. Overall, 40 K can be considered as an easily applicable proxy to assess sedimentation rate of biogenic fraction of particulate matter in marine environments. - Highlights: • 40 K-based approach was developed to assess biogenic sedimentation in the Black Sea. • 40 K-derived relationship between biogenic sedimentation and water depth was traced. • 40 K is an easily applicable proxy to estimate rate of biogenic sedimentation in sea

  7. Planetary gamma-ray spectroscopy: the effects of hydrogen absorption cross-section of the gamma-ray spectrum

    International Nuclear Information System (INIS)

    Lapides, J.R.

    1981-01-01

    The gamma-ray spectroscopy of planet surfaces is one of several possible methods that are useful in determining the elemental composition of planet surfaces from orbiting spacecraft. This has been demonstrated on the Apollos 15 and 16 missions as well as the Soviet Mars-5 mission. Planetary gamma-ray emission is primarily the result of natural radioactive decay and cosmic-ray and solar-flare-induced nuclear reactions. Secondary neutron reactions play a large role in the more intense gamma-ray emission. The technique provides information on the elemental composition of the top few tens of centimeters of the planet surface. Varying concentrations of hydrogen and compositional variations that alter the macroscopic thermal-neutron absorption cross section have a significant effect on the neutron flux in the planet surface and therefore also on the gamma-ray emission from the surface. These effects have been systematically studied for a wide range of possible planetary compositions that include Mercury, the moon, Mars, the comets, and the asteroids. The problem of the Martian atmosphere was also investigated. The results of these calculations, in which both surface neutron fluxes and gamma-ray emission fluxes were determined, were used to develop general procedures for obtaining planet compositions from the gamma-ray spectrum. Several changes have been suggested for reanalyzing the Apollos 15 and 16 gamma-ray results. In addition, procedures have been suggested that can be applied to neutron-gamma techniques in mineral and oil exploration

  8. Determination of natural radioactivity in building materials used in Tunisian dwellings by gamma ray spectrometry

    International Nuclear Information System (INIS)

    Hizem, N.; Fredj, A. B.; Ghedira, L.

    2005-01-01

    The radioisotopic content of 17 samples of natural and manufactured building materials collected in Tunisia have been analysed by using gamma spectrometry. From the measured gamma ray spectra, activity concentrations are determined for 232 Th, 226 Ra, 235 U and 40 K. The total effective dose and the activity concentration index are calculated applying the dose criteria recommended by the European Union for building materials. The results of 226 Ra, 232 Th and 40 K found in Tunisian building materials indicate that radium and thorium concentrations do not exceed 40 Bq kg -1 , but potassium concentration varies between 50 and 1215 Bq kg -1 . The total effective dose rates per person indoors are determined to be between 0.07 and 0.86 mSv y -1 . Only two materials exceed the reference level of 0.3 mSv y -1 . The activity concentration index is <1. (authors)

  9. Conceptual design of the radial gamma ray spectrometers system for α particle and runaway electron measurements at ITER

    Science.gov (United States)

    Nocente, M.; Tardocchi, M.; Barnsley, R.; Bertalot, L.; Brichard, B.; Croci, G.; Brolatti, G.; Di Pace, L.; Fernandes, A.; Giacomelli, L.; Lengar, I.; Moszynski, M.; Krasilnikov, V.; Muraro, A.; Pereira, R. C.; Perelli Cippo, E.; Rigamonti, D.; Rebai, M.; Rzadkiewicz, J.; Salewski, M.; Santosh, P.; Sousa, J.; Zychor, I.; Gorini, G.

    2017-07-01

    We here present the principles and main physics capabilities behind the design of the radial gamma ray spectrometers (RGRS) system for alpha particle and runaway electron measurements at ITER. The diagnostic benefits from recent advances in gamma-ray spectrometry for tokamak plasmas and combines space and high energy resolution in a single device. The RGRS system as designed can provide information on α ~ particles on a time scale of 1/10 of the slowing down time for the ITER 500 MW full power DT scenario. Spectral observations of the 3.21 and 4.44 MeV peaks from the 9\\text{Be}≤ft(α,nγ \\right){{}12}\\text{C} reaction make the measurements sensitive to α ~ particles at characteristic resonant energies and to possible anisotropies of their slowing down distribution function. An independent assessment of the neutron rate by gamma-ray emission is also feasible. In case of runaway electrons born in disruptions with a typical duration of 100 ms, a time resolution of at least 10 ms for runaway electron studies can be achieved depending on the scenario and down to a current of 40 kA by use of external gas injection. We find that the bremsstrahlung spectrum in the MeV range from confined runaways is sensitive to the electron velocity space up to E≈ 30 -40 MeV, which allows for measurements of the energy distribution of the runaway electrons at ITER.

  10. Observation of photon polarization in $B^\\pm \\to K^\\pm\\pi^\\mp\\pi^\\pm\\gamma$ decays

    CERN Multimedia

    Veneziano, G

    2014-01-01

    A study of the flavor-changing neutral current radiative $B^{\\pm} \\to K^{\\pm}\\pi^{\\mp}\\pi^{\\pm}\\gamma$ decays performed using data collected in proton-proton collisions with the LHCb detector at $7$ and $8\\,$TeV center-of-mass energies is presented. In this sample, corresponding to an integrated luminosity of $3\\,\\text{fb}^{-1}$, nearly $14\\,000$ signal events are reconstructed and selected, containing all possible intermediate resonances with a $K^{\\pm}\\pi^{\\mp}\\pi^{\\pm}$ final state in the $[1.1, 1.9]$\\,GeV/$c^{2}$ mass range. The distribution of the angle of the photon direction with respect to the plane defined by the final-state hadrons in their rest frame is studied in intervals of $K^{\\pm}\\pi^{\\mp}\\pi^{\\pm}$ mass and the asymmetry between the number of signal events found on each side of the plane is obtained. The first direct observation of the photon polarization in the $b \\to s\\gamma$ transition is reported with a significance of $5.2\\,\\sigma$.

  11. Impulsive and long duration high-energy gamma-ray emission from the very bright 2012 March 7 solar flares

    Energy Technology Data Exchange (ETDEWEB)

    Ajello, M. [Space Sciences Laboratory, 7 Gauss Way, University of California, Berkeley, CA 94720-7450 (United States); Albert, A.; Allafort, A.; Caliandro, G. A.; Cameron, R. A.; Charles, E. [W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States); Baldini, L. [Università di Pisa and Istituto Nazionale di Fisica Nucleare, Sezione di Pisa I-56127 Pisa (Italy); Barbiellini, G. [Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, I-34127 Trieste (Italy); Bastieri, D.; Buson, S. [Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131 Padova (Italy); Bellazzini, R.; Bregeon, J. [Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, I-56127 Pisa (Italy); Bissaldi, E. [Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, and Università di Trieste, I-34127 Trieste (Italy); Bonamente, E.; Cecchi, C. [Istituto Nazionale di Fisica Nucleare, Sezione di Perugia, I-06123 Perugia (Italy); Brandt, T. J. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Brigida, M. [Dipartimento di Fisica " M. Merlin" dell' Università e del Politecnico di Bari, I-70126 Bari (Italy); Bruel, P. [Laboratoire Leprince-Ringuet, École polytechnique, CNRS/IN2P3, Palaiseau (France); Buehler, R. [Deutsches Elektronen Synchrotron DESY, D-15738 Zeuthen (Germany); Caraveo, P. A., E-mail: nicola.omodei@stanford.edu, E-mail: vahep@stanford.edu, E-mail: melissa.pesce.rollins@pi.infn.it [INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica, I-20133 Milano (Italy); and others

    2014-07-01

    The Fermi Large Area Telescope (LAT) detected gamma-rays up to 4 GeV from two bright X-class solar flares on 2012 March 7, showing both an impulsive and temporally extended emission phases. The gamma-rays appear to originate from the same active region as the X-rays associated with these flares. The >100 MeV gamma-ray flux decreases monotonically during the first hour (impulsive phase) followed by a slower decrease for the next 20 hr. A power law with a high-energy exponential cutoff can adequately describe the photon spectrum. Assuming that the gamma rays result from the decay of pions produced by accelerated protons and ions with a power-law spectrum, we find that the index of that spectrum is ∼3, with minor variations during the impulsive phase. During the extended phase the photon spectrum softens monotonically, requiring the proton index varying from ∼4 to >5. The >30 MeV proton flux observed by the GOES satellites also shows a flux decrease and spectral softening, but with a harder spectrum (index ∼2-3). Based on these observations, we explore the relative merits of prompt or continuous acceleration scenarios, hadronic or leptonic emission processes, and acceleration at the solar corona or by the fast coronal mass ejections. We conclude that the most likely scenario is continuous acceleration of protons in the solar corona that penetrate the lower solar atmosphere and produce pions that decay into gamma rays. However, acceleration in the downstream of the shock cannot be definitely ruled out.

  12. 40 CFR 1060.104 - What running loss emission control requirements apply?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false What running loss emission control... STATIONARY EQUIPMENT Emission Standards and Related Requirements § 1060.104 What running loss emission control requirements apply? (a) Engines and equipment must meet running loss requirements as follows: (1...

  13. 40 CFR 76.5 - NOX emission limitations for Group 1 boilers.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false NOX emission limitations for Group 1 boilers. 76.5 Section 76.5 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.5 NOX emission limitations...

  14. 40 CFR 76.6 - NOX emission limitations for Group 2 boilers.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false NOX emission limitations for Group 2 boilers. 76.6 Section 76.6 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.6 NOX emission limitations...

  15. Extracting $\\gamma$ from $B_{s(d)} \\to J/\\psi K_{S}$ and $B_{d(s)} \\to D^{+}_{d(s)} D^{-}_{d(s)}$

    CERN Document Server

    Fleischer, Robert

    1999-01-01

    A completely general parametrization of the time-dependent decay rates of the modes $B_s\\to J/\\psi K_S$ and $B_d\\to J/\\psi K_S$ is given, which are related to each other through the $U$-spin flavour symmetry of strong interactions. Owing to the interference of current--current and penguin processes, the $B_s\\to J/\\psi K_S$ observables probe the angle $\\gamma$ of the unitarity triangle. Using the $U$-spin symmetry, the overall normalization of the $B_s\\to J/\\psi K_S$ rate can be fixed with the help of the CP-averaged $B_d\\to J/\\psi K_{\\rm S}$ rate, providing a new strategy to determine $\\gamma$. This extraction of $\\gamma$ is not affected by any final-state-interaction effects, and its theoretical accuracy is only limited by $U$-spin-breaking corrections. As a by-product, this strategy allows us to take into account also the penguin effects in the determination of $\\beta$ from $B_d\\to J/\\psi K_S$, which are presumably very small, and to predict the direct CP asymmetry arising in this mode. An analogous strateg...

  16. Enhanced gamma-ray emission from the microquasar Cygnus X-3 detected by AGILE

    Science.gov (United States)

    Piano, G.; Pittori, C.; Verrecchia, F.; Tavani, M.; Bulgarelli, A.; Fioretti, V.; Zoli, A.; Munar-Adrover, P.; Lucarelli, F.; Donnarumma, I.; Vercellone, S.; Striani, E.; Cardillo, M.; Gianotti, F.; Trifoglio, M.; Giuliani, A.; Mereghetti, S.; Caraveo, P.; Perotti, F.; Chen, A.; Argan, A.; Costa, E.; Del Monte, E.; Evangelista, Y.; Feroci, M.; Lazzarotto, F.; Lapshov, I.; Pacciani, L.; Soffitta, P.; Sabatini, S.; Vittorini, V.; Pucella, G.; Rapisarda, M.; Di Cocco, G.; Fuschino, F.; Galli, M.; Labanti, C.; Marisaldi, M.; Pellizzoni, A.; Pilia, M.; Trois, A.; Barbiellini, G.; Vallazza, E.; Longo, F.; Morselli, A.; Picozza, P.; Prest, M.; Lipari, P.; Zanello, D.; Cattaneo, P. W.; Rappoldi, A.; Colafrancesco, S.; Parmiggiani, N.; Ferrari, A.; Antonelli, A.; Giommi, P.; Salotti, L.; Valentini, G.; D'Amico, F.

    2016-04-01

    Integrating from 2016-04-16 00:00 UT to 2016-04-19 00:00 UT, the AGILE-GRID detector is revealing gamma-ray emission above 100 MeV from a source positionally consistent with Cygnus X-3 at Galactic coordinates (l, b) = (79.4, 0.2) +/- 0.6 (stat.) +/- 0.1 (syst.) deg, with flux F( > 100 MeV) = (2.0 +/- 0.8) x 10^-6 photons/cm^2/s, as determined by a multi-source likelihood analysis.

  17. 40K activities and potassium concentrations in tobacco samples of Mexican cigarettes

    International Nuclear Information System (INIS)

    Martinez, T.; Navarrete, M.; Cabrera, L.; Ramos, A.; Vazquez, K.; Juarez, F.

    2007-01-01

    Nine brands of tobacco cigarettes manufactured and distributed in the Mexican market were analyzed by γ-spectrometry to certify their nonartificial radioactive contamination. Since natural occurring radioactive materials (NORM) 40 K, 232 Th, 235 U, and 239 U (and decay products from the latter three nuclides) are the main sources for human radiation exposure, the aim of this work was to determine the activity of 40 K and potassium concentration. Averages of 40 K and potassium concentration were of 1.29 ± 0.18 Bq x g -1 , and 4.0 ± 0.57%. The annual dose equivalents to the whole body from ingestion and inhalation of 26 Bq 40 K were 0.23 μSv and 15.8 μSv, respectively. The corresponding 50 years committed dose equivalents was 0.23 μSv. The total committed dose to the lungs due to inhalation of 40 K in tobacco was 16 μSv. Potassium concentrations obtained in this work were in the same range of those obtained by INAA, so showing that the used technique is acute, reproducible, and accessible to laboratories equipped with low background scintillation detectors. (author)

  18. Radioprotective effects of dimethyl sulfoxide in golden hamster embryo cells exposed to gamma rays at 77 K. I. Radical formation as studied by electron spin resonance

    International Nuclear Information System (INIS)

    Miyazaki, T.; Hayakawa, Y.; Suzuki, K.; Suzuki, M.; Watanabe, M.

    1990-01-01

    Formation of free radicals in golden hamster embryo (GHE) cells in the frozen living state by gamma irradiation has been studied by electron spin resonance spectroscopy at 4.2 and 77 K. The relative yields of H atoms, OH radicals, and organic radicals trapped in the irradiated GHE cells are 12, 72, and 16%, respectively, of total radical yields. When dimethylsulfoxide (DMSO) is added to GHE cells at 77 K, a large quantity of CH2SOCH3 radicals (DMSO radicals) are formed after gamma irradiation. The yields of OH radicals are not affected by the addition of DMSO. When the GHE cell-DMSO mixtures are irradiated with gamma rays at 77 K and then warmed to 111 K, the OH radicals decay, whereas the DMSO radicals do not increase complementarily. Moreover, the decay rates of the OH radicals at 111 K do not depend upon the concentration of DMSO. Thus OH radicals do not react with DMSO during warming of the irradiated sample. When H atoms are produced by gamma irradiation of acid ice at 60 K, the decay rates of the H atoms at 77 K increase with increasing DMSO concentration, indicating that DMSO reacts with H atoms (CH3SOCH3 + H----.CH2SOCH3 + H2) at 77 K by quantum-mechanical tunneling. When the GHE cell-DMSO mixture is irradiated with gamma rays at 77 or 4.2 K in the dark, DMSO ions are produced in addition to DMSO radicals. Therefore it is concluded that DMSO does not scavenge OH radicals, but does capture H atoms, holes and/or electrons in the gamma-irradiated cells, resulting in the remarkable formation of DMSO radicals. This scavenger effect of DMSO may be related to the radioprotection of DMSO against cell killing

  19. Effect of gamma irradiation and its convergent treatment for control of postharvest Botrytis cinerea of cut roses

    Science.gov (United States)

    Chu, Eun-Hee; Shin, Eun-Jung; Park, Hae-Jun; Jeong, Rae-Dong

    2015-10-01

    Postharvest diseases cause considerable losses to harvested crops. Among them, gray mold (Botrytis cinerea) is a major problem of exporting to cut rose flowers into Korea. Irradiation treatment is an alternative to phytosanitary purposes and a useful nonchemical approach to the control of postharvest diseases. Gamma irradiation was evaluated for its in vitro and in vivo antifungal activity against B. cinerea on cut rose varieties, 'Shooting Star' and 'Babe'. The irradiating dose required to reduce the population by 90%, D10, was 0.99 kGy. Gamma irradiation showed complete inhibition of spore germination and mycelial growth of B. cinerea, especially 4.0 kGy in vitro. Antifungal activity of gamma irradiation on rose B. cinerea is a dose-dependent manner. A significant phytotoxicity such as bent neck in cut rose quality was shown from gamma irradiation at over 0.4 kGy (ptechnology for horticulture products for exportation.

  20. Spectral analysis of K-shell X-ray emission of magnesium plasma

    Indian Academy of Sciences (India)

    2014-02-06

    Feb 6, 2014 ... Spectral analysis of K-shell X-ray emission of magnesium plasma, produced by laser pulses of 45 fs duration, focussed up to an intensity of ∼1018 W cm-2, is carried out. The plasma conditions prevalent during the emission of X-ray spectrum were identified by comparing the experimental spectra with the ...

  1. Gamma-ray emission from 80-86As isotopes

    International Nuclear Information System (INIS)

    Kratz, J.V.; Franz, H.; Kaffrell, N.; Hermann, G.

    1975-01-01

    Activities of 80-86 As were produced in (n,p) reactions on stable selenium nuclei as fission products, and via β - decay from their precursors. To separate arsenic and germanium from fission product mixtures, rapid chemical separations were applied. Gamma-ray emission from arsenic isotopes was studied in γ-singles and γγ coincidence experiments. Partial decay schemes are proposed for 34sec 81 As, 14.0sec and 19.1sec 82 As, 13.3sec 83 As and 5.3sec 84 As. The delayed-neutron branch in the decay of 2.05sec 85 As was shown to preferentially populate several excited levels in 84 Se while the ground state of 84 Se is fed to 29% only. The systematics of low-lying levels in doubly even selenium isotopes is extended up to mass number 86. Discontinuities in the systematics at N=48 are interpreted as an indication of a soft character of the nucleus 82 Se. (Auth.)

  2. A model problem for restricted-data gamma ray emission tomography of highly active nuclear waste

    International Nuclear Information System (INIS)

    Cattle, Brian A.

    2007-01-01

    This paper develops the work of Cattle et al. [Cattle, B.A., Fellerman, A.S., West, R.M., 2004. On the detection of solid deposits using gamma ray emission tomography with limited data. Measurement Science and Technology 15, 1429-1439] by considering a generalization of the model employed therein. The focus of the work is the gamma ray tomographic analysis of high-level waste processing. The work in this paper considers a two-dimensional model for the measurement of gamma ray photon flux, as opposed to the previous one-dimensional analysis via the integrated Beer-Lambert law. The mathematical inverse problem that arises in determining physical quantities from the photon count measurements is tackled using Bayesian statistical methods that are implemented computationally using a Markov chain Monte Carlo (MCMC) approach. In a further new development, the effect of the degree of collimation of the detector on the reliability of the solutions is also considered

  3. Gamma spectrometric method for measuring natural radioactivity of building materials

    International Nuclear Information System (INIS)

    Toth, A.; Feher, I.

    1976-11-01

    The natural 232 Th, 226 Ra and 40 K concentrations of building materials were determined by gamma spectrometry. Altogether 121 samples from all over Hungary, one from each factory producing building materials, were examined. The presented data had preliminary character. The results were compared to the relating ones from abroad. (Sz.N.Z.)

  4. 40 CFR 1054.501 - How do I run a valid emission test?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false How do I run a valid emission test... Procedures § 1054.501 How do I run a valid emission test? (a) Applicability. This subpart is addressed to you... provisions of 40 CFR 1065.405 describes how to prepare an engine for testing. However, you may consider...

  5. Circumstellar X-ray Emission from SN1978K

    Science.gov (United States)

    Schlegel, Eric M.; Colbert, E.; Petre, R.

    1995-02-01

    We present the X-ray light curve in the 0.2 2.4 keV band based on fiveROSAT observations of SN1978K in NGC 1313. The X-ray emission is believed to arise from the interaction of the reverse shock and the expanding debris from the supernova. The reverse shock becomes established after the outgoing shock runs into circumstellar matter.

  6. Application of the Monte Carlo method for the efficiency calibration of CsI and NaI detectors for gamma-ray measurements from terrestrial samples

    International Nuclear Information System (INIS)

    Baccouche, S.; Al-Azmi, D.; Karunakara, N.; Trabelsi, A.

    2012-01-01

    Gamma-ray measurements in terrestrial/environmental samples require the use of high efficient detectors because of the low level of the radionuclide activity concentrations in the samples; thus scintillators are suitable for this purpose. Two scintillation detectors were studied in this work; CsI(Tl) and NaI(Tl) with identical size for measurement of terrestrial samples for performance study. This work describes a Monte Carlo method for making the full-energy efficiency calibration curves for both detectors using gamma-ray energies associated with the decay of naturally occurring radionuclides 137 Cs (661 keV), 40 K (1460 keV), 238 U ( 214 Bi, 1764 keV) and 232 Th ( 208 Tl, 2614 keV), which are found in terrestrial samples. The magnitude of the coincidence summing effect occurring for the 2614 keV emission of 208 Tl is assessed by simulation. The method provides an efficient tool to make the full-energy efficiency calibration curve for scintillation detectors for any samples geometry and volume in order to determine accurate activity concentrations in terrestrial samples. - Highlights: ► CsI (Tl) and NaI (Tl) detectors were studied for the measurement of terrestrial samples. ► Monte Carlo method was used for efficiency calibration using natural gamma emitting terrestrial radionuclides. ► The coincidence summing effect occurring for the 2614 keV emission of 208 Tl is assessed by simulation.

  7. Discovery of TeV gamma-ray emission from the pulsar wind nebula 3C 58 by MAGIC

    Directory of Open Access Journals (Sweden)

    López-Coto Rubén

    2016-01-01

    Full Text Available The pulsar wind nebula (PWN 3C 58 is one of the historical very-high-energy (VHE; E>100 GeV gamma-ray source candidates. It has been compared to the Crab Nebula due to their morphological similarities. This object was detected by Fermi-LAT with a spectrum extending beyond 100 GeV. We analyzed 81 hours of 3C 58 data taken with the MAGIC telescopes and we detected VHE gamma-ray emission for the first time at TeV energies with a significance of 5.7 sigma and an integral flux of 0.65% C.U. above 1 TeV. According to our results 3C 58 is the least luminous PWN ever detected at VHE and the one with the lowest flux at VHE to date. We compare our results with the expectations of time-dependent models in which electrons up-scatter photon fields. The best representation favors a distance to the PWN of 2 kpc and Far Infrared (FIR comparable to CMB photon fields. Hadronic contribution from the hosting supernova remnant (SNR requires unrealistic energy budget given the density of the medium, disfavoring cosmic ray acceleration in the SNR as origin of the VHE gamma-ray emission.

  8. Gamma ray doses proceeding from natural occurring radionuclides in closed environments

    International Nuclear Information System (INIS)

    Aguiar, Vitor Angelo P. de; Medina, Nilberto H.; Silveira, Marcilei A. Guazzelli da; Moreira, Ramon H.

    2009-01-01

    In this work we report on the application of gamma-ray spectrometry in the study of the effective dose coming from terrestrial natural elements present in building materials such as sand, cement, lime (CaO) and milled granitic stones. The major contribution to annual gamma-ray radiation effective dose is due to the natural occurring radionuclides 40 K, 232 Th and 238 U. Two spectrometry systems were employed to measure the gamma radiation: one with a 60% efficient GeHP detector and the second one with a 2''x2'' NaI(Tl) scintillator. The estimated effective dose coming from the three reference rooms assumed is 0.63 mSv/yr, proceeding from terrestrial natural elements. The principal gamma radiation sources are cement, sand and bricks. (author)

  9. Observations of the highest energy gamma-rays from gamma-ray bursts

    International Nuclear Information System (INIS)

    Dingus, Brenda L.

    2001-01-01

    EGRET has extended the highest energy observations of gamma-ray bursts to GeV gamma rays. Such high energies imply the fireball that is radiating the gamma-rays has a bulk Lorentz factor of several hundred. However, EGRET only detected a few gamma-ray bursts. GLAST will likely detect several hundred bursts and may extend the maximum energy to a few 100 GeV. Meanwhile new ground based detectors with sensitivity to gamma-ray bursts are beginning operation, and one recently reported evidence for TeV emission from a burst

  10. Effects of Gamma Irradiation on Active Components in Essential Oils of Cinnamomum verum J.S.Presl

    International Nuclear Information System (INIS)

    Thongphasuk, Piyanuch; Thongphasuk, Jarunee; Eamsiri, Jarurut; Pongpat, Suchada

    2009-07-01

    Full text: Gamma irradiation is one of the methods utilized to reduce microbial contamination of medicinal herbs. Since irradiation may also affect active compounds of the irradiated herbs, the objective of this research is to study the effect of gamma irradiation (10 and 25 kGy) from cobalt-60 on active compounds in essential oils of Cinnamomum verum J.S.Presl by using GC-MS. The results showed that gamma irradiation at the dose of 10 and 25 kGy does not significantly affect active components in essential oils such as alpha-pinene, camphene, 1,8-cineole, alpha-copaene, benzaldehyde, linalool, bornyl acetate, terpinen-4-0l, alpha-terpineol, benzylacetaldehyde, Z-cinnamaldehyde, E-cinnamaldehyde, and cinnamic acid

  11. Gamma radiation effects on phenolics, antioxidants activity and in vitro digestion of pistachio (Pistachia vera) hull

    Energy Technology Data Exchange (ETDEWEB)

    Behgar, M [Agricultural, Medical and Industrial Research School, P.O. Box 31485498, Karaj (Iran, Islamic Republic of); Ghasemi, S; Naserian, A [Faculty of Agriculture, Excellence Center in Animal Science, Ferdowsi University of Mashhad, P.O. Box 917751163, Mashhad (Iran, Islamic Republic of); Borzoie, A; Fatollahi, H [Agricultural, Medical and Industrial Research School, P.O. Box 31485498, Karaj (Iran, Islamic Republic of)

    2011-09-15

    The effect of gamma radiation (10, 20, 30, 40, 50 and 60 kGy) on tannin, total phenolics, antioxidants activity and in vitro digestion of pistachio hulls has been investigated in this study. The possibility of using the radial diffusion method based on software measurement of the rings area has also been investigated in this study. The software based method in radial diffusion method showed a higher r{sup 2} (0.995) value when compared to the traditional method. Irradiation reduced the tannin content (P<0.01) and activity of antioxidants (P<0.05) of pistachio hull extracts but increased the total phenolic content (P<0.05). There was no effect of gamma irradiation on the in vitro digestion of the pistachio hull. Irradiation decreased the digestion rate of the pistachio hull at the dose of 40 kGy when compared to the control. This study showed that gamma irradiation decreased tannin and antioxidants activity of pistachio hull. - Highlights: > we investigate the effects of gamma irradiation on pistachio hull. > We examine changes in phenolics, antioxidant and digestion of pistachio hull. > Computerized radial diffusion method gives precise regression for standard curve. > Gamma irradiation will decrease tannin and antioxidants of pistachio hull extracts.

  12. Gamma radiation effects on phenolics, antioxidants activity and in vitro digestion of pistachio (Pistachia vera) hull

    International Nuclear Information System (INIS)

    Behgar, M.; Ghasemi, S.; Naserian, A.; Borzoie, A.; Fatollahi, H.

    2011-01-01

    The effect of gamma radiation (10, 20, 30, 40, 50 and 60 kGy) on tannin, total phenolics, antioxidants activity and in vitro digestion of pistachio hulls has been investigated in this study. The possibility of using the radial diffusion method based on software measurement of the rings area has also been investigated in this study. The software based method in radial diffusion method showed a higher r 2 (0.995) value when compared to the traditional method. Irradiation reduced the tannin content (P<0.01) and activity of antioxidants (P<0.05) of pistachio hull extracts but increased the total phenolic content (P<0.05). There was no effect of gamma irradiation on the in vitro digestion of the pistachio hull. Irradiation decreased the digestion rate of the pistachio hull at the dose of 40 kGy when compared to the control. This study showed that gamma irradiation decreased tannin and antioxidants activity of pistachio hull. - Highlights: → we investigate the effects of gamma irradiation on pistachio hull. → We examine changes in phenolics, antioxidant and digestion of pistachio hull. → Computerized radial diffusion method gives precise regression for standard curve. → Gamma irradiation will decrease tannin and antioxidants of pistachio hull extracts.

  13. Development of an airborne gamma radiation system for snow surveys

    Energy Technology Data Exchange (ETDEWEB)

    Fritzsche, A E [EG and G, Inc., Las Vegas, NV (USA)

    1979-01-01

    An airborne gamma-snow survey system requires detailed design to obtain maximum precision and accuracy. The use of NaI(Te) gamma detectors with a full gamma energy spectrum pulse height analyzer together with a small computer provide a self-contained and flexible system. The dual detector method determines atmospheric radon perturbations in the detection system. Detailed calibration experiments must be performed to determine twenty parameters that describe the physical nature of the system. Multiple high altitude and lake flights are used to obtain background components. Simulation pads, loaded with varying concentrations of /sup 40/K, /sup 232/Th and /sup 23/..gamma..U yield photopeak stripping coefficients and basic system sensitivity. Multiple altitude flights over land lines provide air attenuation coefficients which may converted to water attenuation coefficients.

  14. Time-resolved spectral analysis of prompt emission from long gamma-ray bursts with GeV emission

    International Nuclear Information System (INIS)

    Rao Arikkala Raghurama; Basak Rupal; Bhattacharya Jishnu; Chandra Sarthak; Maheshwari Nikunj; Choudhury Manojendu; Misra Ranjeev

    2014-01-01

    We performed detailed time-resolved spectroscopy of bright long gamma-ray bursts (GRBs) which show significant GeV emissions (GRB 080916C, GRB 090902B and GRB 090926A). In addition to the standard Band model, we also use a model consisting of a black body and a power law to fit the spectra. We find that for the latter model there are indications of an additional soft component in the spectra. While previous studies have shown that such models are required for GRB 090902B, here we find that a composite spectral model consisting of two blackbodies and a power law adequately fits the data of all the three bright GRBs. We investigate the evolution of the spectral parameters and find several interesting features that appear in all three GRBs, like (a) temperatures of the blackbodies are strongly correlated with each other, (b) fluxes in the black body components are strongly correlated with each other, (c) the temperatures of the black body trace the profile of the individual pulses of the GRBs, and (d) the characteristics of power law components like the spectral index and the delayed onset bear a close similarity to the emission characteristics in the GeV regions. We discuss the implications of these results and the possibility of identifying the radiation mechanisms during the prompt emission of GRBs. (research papers)

  15. Natural radioactivity levels (K, Th and Ra in some areas of Punjab, India

    Directory of Open Access Journals (Sweden)

    Kumar Sanjeev

    2012-04-01

    Full Text Available Radioactivity, natural and man-made, is omnipresent in the earth's crust in different amounts. Natural radioactive materials under certain conditions can reach hazardous radiological levels. So, it becomes necessary to study the natural radioactivity levels in soil to assess the dose for the population in order to know the health risks and to have a baseline for future changes in the environmental radioactivity due to human activities. 226Ra, 232Th and 40K analysis has been carried out in soil samples collected from some areas of Punjab, India using gamma-ray spectrometry. Phe technique of gamma ray spectrometry was applied using high purity germanium gamma-ray detector and a PC based MCA. Radium equivalent activities are calculated for the analyzed samples to assess radiation hazards arising due to the use of these soil samples in construction of dwellings. Phe measured activity in the soil ranges from 23.17 to 57.87 Bq kg−1, 59.03 to 160.40 Bq kg−1 and 228.06 to 501.03 Bq kg−1 for 226Ra, 232Ph and 40K with mean values of 37.93, 84.47 and 351.17Bqkg−1 respectively. It has been observed that on the average the outdoor terrestrial gamma air absorbed dose rate is about 84.65nGyh−1.

  16. Estimation of the self-attenuation correction factor for gamma rays emission from nuclear materials

    International Nuclear Information System (INIS)

    Badawy, A.; El-Gammal, W.A.

    2001-01-01

    This work presents an investigation of the self-attenuation of gamma-rays emission from nuclear materials (NMs) for measuring the U-235 enrichment, U-235 mass content and isotopic composition of NMs by non-destructive assay technique [NDA]. The measurements then would not need the use of suitable NM Standards which may not be available in many situations. The self-attenuation correction factor (F) may be estimated by the use of the linear attenuation factor of the assayed sample, the geometrical configuration of the assay set-up and the position of the assayed sample relative to the detector. A developed mathematical analysis makes use of specific parameters which affect the estimation of the self-attenuation of the source-detector system which emits passive gamma-rays at certain prominent signatures

  17. 40 CFR 75.19 - Optional SO2, NOX, and CO2 emissions calculation for low mass emissions (LME) units.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Optional SO2, NOX, and CO2 emissions... § 75.19 Optional SO2, NOX, and CO2 emissions calculation for low mass emissions (LME) units. (a... input, NOX, SO2, and CO2 mass emissions, and NOX emission rate under this part. If the owner or operator...

  18. 40 CFR 60.4154 - Compliance with Hg budget emissions limitation.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Compliance with Hg budget emissions... Times for Coal-Fired Electric Steam Generating Units Hg Allowance Tracking System § 60.4154 Compliance with Hg budget emissions limitation. (a) Allowance transfer deadline. The Hg allowances are available...

  19. Constraints on millisecond magnetars as the engines of prompt emission in gamma-ray bursts

    Science.gov (United States)

    Beniamini, Paz; Giannios, Dimitrios; Metzger, Brian D.

    2017-12-01

    We examine millisecond magnetars as central engines of gamma-ray bursts' (GRBs) prompt emission. Using the protomagnetar wind model of Metzger et al., we estimate the temporal evolution of the magnetization and power injection at the base of the GRB jet and apply these to different prompt emission models to make predictions for the GRB energetics, spectra and light curves. We investigate both shock and magnetic reconnection models for the particle acceleration, as well as the effects of energy dissipation across optically thick and thin regions of the jet. The magnetization at the base of the jet, σ0, is the main parameter driving the GRB evolution in the magnetar model and the emission is typically released for 100 ≲σ0 ≲3000. Given the rapid increase in σ0 as the protomagnetar cools and its neutrino-driven mass loss subsides, the GRB duration is typically limited to ≲100 s. This low baryon loading at late times challenges magnetar models for ultralong GRBs, though black hole models likely run into similar difficulties without substantial entrainment from the jet walls. The maximum radiated gamma-ray energy is ≲5 × 1051 erg, significantly less than the magnetar's total initial rotational energy and in strong tension with the high end of the observed GRB energy distribution. However, the gradual magnetic dissipation model applied to a magnetar central engine, naturally explains several key observables of typical GRBs, including energetics, durations, stable peak energies, spectral slopes and a hard to soft evolution during the burst.

  20. LHCb: Tagged time-dependent angular analysis of $B^0_s \\to J/\\psi K^+ K^-$ at LHCb

    CERN Multimedia

    Syropoulos, V

    2013-01-01

    The time-dependent CP-violating asymmetry in $B^0_s\\to J/\\psi K^{+}K^{-}$ decays is measured using $1.0^{-1}$ of $pp$ of collisions at $\\sqrt{s}=7$ TeV collected with the LHCb detector. The decay time distribution of $B^0_s\\to J/\\psi K^{+}K^{-}$ is characterized by the decay widths $\\Gamma_{\\mathrm{H}}$ and $\\Gamma_{\\mathrm{L}}$ of the heavy and light mass eigenstates of the $B^0_s - \\bar{B^0_s}$ system and by a CP-violating phase $\\phi_s$. In a sample of approximately 27600 $B^0_s\\to J/\\psi K^{+}K^{-}$ events we measure $\\phi_s \\: = \\: 0.068 \\: \\pm \\: 0.091 \\: \\text{(stat)} \\: \\pm \\: 0.011 \\: \\text{(syst)} \\: \\text{rad}$. We also find an average $B^0_s$ decay width $\\Gamma_s \\equiv (\\Gamma_{\\mathrm{L}}+\\Gamma_{\\mathrm{H}})/2 \\: = \\: 0.671 \\: \\pm \\: 0.005 \\: \\text{(stat)} \\: \\pm \\: 0.006 \\: \\text{(syst)} \\: ps^{-1}$ and a decay width difference $\\Delta \\Gamma_s \\equiv \\Gamma_{\\mathrm{L}} - \\Gamma_{\\mathrm{H}} \\: = \\: 0.100 \\: \\pm \\: 0.016 \\: \\text{(stat)} \\: \\pm \\: 0.003 \\: \\text{(syst)} \\: ps^...

  1. Discovery of Giant Gamma-ray Bubbles in the Milky Way

    Science.gov (United States)

    Su, Meng

    Based on data from the Fermi Gamma-ray Space Telescope, we have discovered two gigantic gamma-ray emitting bubble structures in our Milky Way (known as the Fermi bubbles), extending ˜50 degrees above and below the Galactic center with a width of ˜40 degrees in longitude. The gamma-ray emission associated with these bubbles has a significantly harder spectrum (dN/dE ˜ E-2) than the inverse Compton emission from known cosmic ray electrons in the Galactic disk, or the gamma-rays produced by decay of pions from proton-ISM collisions. There is no significant difference in the spectrum or gamma-ray luminosity between the north and south bubbles. The bubbles are spatially correlated with the hard-spectrum microwave excess known as the WMAP haze; we also found features in the ROSAT soft X-ray maps at 1.5 -- 2 keV which line up with the edges of the bubbles. The Fermi bubbles are most likely created by some large episode of energy injection in the Galactic center, such as past accretion events onto the central massive black hole, or a nuclear starburst in the last ˜ 10 Myr. Study of the origin and evolution of the bubbles also has the potential to improve our understanding of recent energetic events in the inner Galaxy and the high-latitude cosmic ray population. Furthermore, we have recently identified a gamma-ray cocoon feature within the southern bubble, with a jet-like feature along the cocoon's axis of symmetry, and another directly opposite the Galactic center in the north. If confirmed, these jets are the first resolved gamma-ray jets ever seen.

  2. Particle-Induced Gamma-ray Emission Spectroscopy Over a Broad Range of Elements

    Science.gov (United States)

    Olds, Hannah; Wilkinson, John; Tighe, Meghanne; McLallen, Walter; McGuire, Patrick

    2017-09-01

    Ion beam analysis is a common application of nuclear physics that allows elemental and isotopic information about materials to be determined from accelerated light ion beams One of the best know ion beam analysis techniques is Particle-Induced Gamma-ray Emission (PIGE) spectroscopy, which can be used ex vacuo to identify the elements of interest in almost any solid target. The energies of the gamma-rays emitted by excited nuclei will be unique to each element and depend on its nuclear structure. For the most sensitivity, the accelerated ions should exceed the Coulomb barrier of the target, but many isotopes are known to be accessible to PIGE even below the Coulomb barrier. To explore the sensitivity of PIGE across the periodic table, PIGE measurements were made on elements with Z = 5, 9, 11-15, 17, 19-35, 37, 42, 44-48, 53, 56, 60, 62, 73, and 74 using 3.4 MeV protons. These measurements will be compared with literature values and be used as a basis for comparison with higher-energy proton beams available at the University of Notre Dame's St. Andre accelerator when it comes online this Fall. The beam normalization technique of using atmospheric argon and its 1459 keV gamma-ray to better estimate the integrated beam on target will also be discussed. Funded by the NSF REU program and the University of Notre Dame.

  3. Fermi Bubble: Giant Gamma-Ray Bubbles in the Milky Way

    Science.gov (United States)

    Su, Meng

    Data from the Fermi-LAT reveal two gigantic gamma-ray emitting bubble structures (known as the Fermibubbles), extending˜50° above and below the Galactic center symmetric about the Galactic plane, with a width of˜40∘ in longitude. The gamma-ray emission associated with these bubbles has a significantly harder spectrum ({dN}/{dE} ˜ {E}^{-2}) than the inverse Compton emission from known cosmic ray electrons in the Galactic disk, or the gamma-rays produced by decay of pions from proton-ISM collisions. The bubbles are spatially correlated with the hard-spectrum microwave excess known as the WMAPhaze; the edges of the bubbles also line up with features in the ROSATsoft X-ray maps at 1.5-2keV. The Fermibubble is most likely created by some large episode of energy injection in the Galactic center, such as past accretion events onto the central massive black hole, or a nuclear starburst in the last˜10Myr. Study of the origin and evolution of the bubbles also has the potential to improve our understanding of recent energetic events in the inner Galaxy and the high-latitude cosmic ray population.

  4. Study of the gamma emission from the 31-year isomer of 178Hf induced by X-ray irradiation

    International Nuclear Information System (INIS)

    Collins, C.B.; Davanloo, F.; Iosif, M.C.

    1999-01-01

    A sample containing 6.3x10 14 nuclei of the 16 + isomer of 178 Hf having a half-life of 31 years and excitation energy of 2.446 MeV was irradiated with x-ray pulses derived from a device operated at 15mA to produce Bremsstrahlung radiation with an end point energy set to be 90 keV. Gamma-spectra of the isomeric target were taken with a Ge-detector. Intensity of the 325.5 keV (6 + →4 + transition in the ground state band of 178 Hf was found to increase by about 2%. Such an accelerated decay of the 178 Hf isomer is consistent with an integrated cross section of 3x10 -23 cm 2 ·keV if the resonant absorption takes place within the energy ranges corresponding to the maxima of the x-ray flux, either near 20 keV, or at the K emission lines of W

  5. Assessment of oleoresin and gingerol contents in gamma irradiated ginger Rhizomes

    International Nuclear Information System (INIS)

    Onyenekwe, P.C.

    2000-01-01

    Oleoresin and gingerol contents in gamma irradiated dried ginger rhizomes were evaluated to determine the effect of radiation and storage on these constituents of ginger. Dried ginger rhizomes were subjected to 0, 5 and 10 kilogray (kGy) doses of gamma rays from 60Co source. The oleoresin and gingerol contents were monitored for 9 months. Radiation treatment (10 kGy) reduced the decrease of the oleoresin content of ginger during the storage period by 14% in unground samples and 11% in ground samples. There was a dose-dependent decrease in the 6-gingerol content of the ground ginger decreased by 65.6, 67.4 and 70.4% for the 0, 5, and 10 kGy samples, respectively, while the corresponding values for the ungrounded ginger samples were 37.8, 40.0 and 44.3% at the end of the storage period

  6. STUDY OF NATURAL RADIOACTIVITY (226Ra, 232Th AND 40K) IN SOIL SAMPLES FOR THE ASSESSMENT OF AVERAGE EFFECTIVE DOSE AND RADIATION HAZARDS.

    Science.gov (United States)

    Bangotra, Pargin; Mehra, Rohit; Kaur, Kirandeep; Jakhu, Rajan

    2016-10-01

    The activity concentration of 226 Ra (radium), 232 Th (thorium) and 40 K (potassium) has been measured in the soil samples collected from Mansa and Muktsar districts of Punjab (India) using NaI (Tikl) gamma detector. The concentration of three radionuclides ( 226 Ra, 232 Th and 40 K) in the studied area has been varied from 18±4 to 46±5, 53±7 to 98±8 and 248±54 to 756±110 Bq kg -1 , respectively. Radium equivalent activities (Ra eq ) have been calculated in soil samples for the assessment of the radiation hazards arising due to the use of these soil samples. The absorbed dose rate of 226 Ra, 232 Th and 40 K in studied area has been varied from 8 to 21, 33 to 61 and 9 to 25 nGy h -1 , respectively. The corresponding indoor and outdoor annual effective dose in studied area was 0.38 and 0.09 mSv, respectively. The external and internal hazard has been also calculated for the assessment of radiation hazards in the studied area. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Risk to Krakow population of gamma radiation from building materials

    International Nuclear Information System (INIS)

    Koperski, J.; Jasinska, M.

    1980-01-01

    A statistics was made of 7128 dwelling-houses considering their age, types of building materials and density of population. Gamma dose rates were measured by means of the TL and pressurized ionization chamber techniques inside 300 buildings and in 44 points outdoors over different kinds of beddings. Personal doses of 49 inhabitants of the buildings monitored were also recorded. By means of the spectrometric analysis of gamma radiation, and basing on a specially developed computational programme ''DOZA'' mean concentrations of 40 K, 226 Ra and 232 Th in 61 samples of building materials were evaluated. It was found that the mean personal dose rate as well as the mean indoor dose rate equals 5.7 urad/h /15.8 pGy/s/ and is about 19% higher than the dose outdoors which equals 4.8 urad/h /13.3 pGy/s/. Gamma dose rates inside the buildings made of gravel-sand concrete elements are about 10% lower than those in the buildings made of red bricks. Mean annual dose equivalent per capita from gamma radiation of building materials equals 40.6 mrem/y /406 uSv/y/, which constitutes about 57% of total annual dose equivalent per capita from all environmental sources of gamma radiation in the residential districts in Krakow. (author)

  8. Search for very high-energy gamma-ray emission from the microquasar Cygnus X-1 with the MAGIC telescopes

    Science.gov (United States)

    Ahnen, M. L.; Ansoldi, S.; Antonelli, L. A.; Arcaro, C.; Babić, A.; Banerjee, B.; Bangale, P.; Barres de Almeida, U.; Barrio, J. A.; Becerra González, J.; Bednarek, W.; Bernardini, E.; Berti, A.; Bhattacharyya, W.; Biasuzzi, B.; Biland, A.; Blanch, O.; Bonnefoy, S.; Bonnoli, G.; Carosi, R.; Carosi, A.; Chatterjee, A.; Colin, P.; Colombo, E.; Contreras, J. L.; Cortina, J.; Covino, S.; Cumani, P.; da Vela, P.; Dazzi, F.; de Angelis, A.; de Lotto, B.; de Oña Wilhelmi, E.; di Pierro, F.; Doert, M.; Domínguez, A.; Dominis Prester, D.; Dorner, D.; Doro, M.; Einecke, S.; Eisenacher Glawion, D.; Elsaesser, D.; Engelkemeier, M.; Fallah Ramazani, V.; Fernández-Barral, A.; Fidalgo, D.; Fonseca, M. V.; Font, L.; Fruck, C.; Galindo, D.; García López, R. J.; Garczarczyk, M.; Gaug, M.; Giammaria, P.; Godinović, N.; Gora, D.; Guberman, D.; Hadasch, D.; Hahn, A.; Hassan, T.; Hayashida, M.; Herrera, J.; Hose, J.; Hrupec, D.; Ishio, K.; Konno, Y.; Kubo, H.; Kushida, J.; Kuveždić, D.; Lelas, D.; Lindfors, E.; Lombardi, S.; Longo, F.; López, M.; Maggio, C.; Majumdar, P.; Makariev, M.; Maneva, G.; Manganaro, M.; Mannheim, K.; Maraschi, L.; Mariotti, M.; Martínez, M.; Mazin, D.; Menzel, U.; Minev, M.; Mirzoyan, R.; Moralejo, A.; Moreno, V.; Moretti, E.; Neustroev, V.; Niedzwiecki, A.; Nievas Rosillo, M.; Nilsson, K.; Ninci, D.; Nishijima, K.; Noda, K.; Nogués, L.; Paiano, S.; Palacio, J.; Paneque, D.; Paoletti, R.; Paredes, J. M.; Paredes-Fortuny, X.; Pedaletti, G.; Peresano, M.; Perri, L.; Persic, M.; Prada Moroni, P. G.; Prandini, E.; Puljak, I.; Garcia, J. R.; Reichardt, I.; Rhode, W.; Ribó, M.; Rico, J.; Righi, C.; Saito, T.; Satalecka, K.; Schroeder, S.; Schweizer, T.; Sitarek, J.; Šnidarić, I.; Sobczynska, D.; Stamerra, A.; Strzys, M.; Surić, T.; Takalo, L.; Tavecchio, F.; Temnikov, P.; Terzić, T.; Tescaro, D.; Teshima, M.; Torres, D. F.; Torres-Albà, N.; Treves, A.; Vanzo, G.; Vazquez Acosta, M.; Vovk, I.; Ward, J. E.; Will, M.; Zarić, D.; MAGIC Collaboration; Bosch-Ramon, V.; Pooley, G. G.; Trushkin, S. A.; Zanin, R.

    2017-12-01

    The microquasar Cygnus X-1 displays the two typical soft and hard X-ray states of a black hole transient. During the latter, Cygnus X-1 shows a one-sided relativistic radio-jet. Recent detection of the system in the high energy (HE; E ≳ 60 MeV) gamma-ray range with Fermi-LAT associates this emission with the outflow. Former MAGIC observations revealed a hint of flaring activity in the very high-energy (VHE; E ≳ 100 GeV) regime during this X-ray state. We analyse ∼97 h of Cygnus X-1 data taken with the MAGIC telescopes between July 2007 and October 2014. To shed light on the correlation between hard X-ray and VHE gamma rays as previously suggested, we study each main X-ray state separately. We perform an orbital phase-folded analysis to look for variability in the VHE band. Additionally, to place this variability behaviour in a multiwavelength context, we compare our results with Fermi-LAT, AGILE, Swift-BAT, MAXI, RXTE-ASM, AMI and RATAN-600 data. We do not detect Cygnus X-1 in the VHE regime. We establish upper limits for each X-ray state, assuming a power-law distribution with photon index Γ = 3.2. For steady emission in the hard and soft X-ray states, we set integral upper limits at 95 per cent confidence level for energies above 200 GeV at 2.6 × 10-12 photons cm-2 s-1 and 1.0 × 10-11 photons cm-2 s-1, respectively. We rule out steady VHE gamma-ray emission above this energy range, at the level of the MAGIC sensitivity, originating in the interaction between the relativistic jet and the surrounding medium, while the emission above this flux level produced inside the binary still remains a valid possibility.

  9. Uptake of 40K and 137Cs in native plants of the Marshall Islands.

    Science.gov (United States)

    Simon, S L; Graham, J C; Terp, S D

    2002-01-01

    Uptake of 137Cs and 40K was studied in seven native plant species of the Marshall Islands. Plant and soil samples were obtained across a broad range of soil 137Cs concentrations (0.08-3900 Bq/kg) and a narrower range of 40K soil concentrations (2.3-55 Bq/kg), but with no systematic variation of 40K relative to 137Cs. Potassium-40 concentrations in plants varied little within the range of 40K soil concentrations observed. Unlike the case for 40K, 137Cs concentrations increased in plants with increasing 137Cs soil concentrations though not precisely in a proportionate manner. The best-fit relationship between soil and plant concentrations was P = aSb where a and b are regression coefficients and P and S are plant and soil concentrations, respectively. The exponent b for 40K was zero, implying plant concentrations were a single value, while b for 137Cs varied between 0.51 and 0.82, depending on the species. For both 40K and 137Cs, we observed a decreasing concentration ratio (where concentration ratio=plant concentration/soil concentration) with increasing soil concentrations. For the CR values, the best-fit relationship was of the form CR = aSb/S = aSb(-1). For the 40K CR functions, the exponent b - 1 was close to - 1 for all species. For the 137Cs CR functions, the exponent b - 1 varied from -0.19 to -0.48. The findings presented here, aswell as those by other investigators, collectively argue against the usefulness of simplistic ratio models to accurately predict uptake of either 40K or 137Cs in plants over wide ranges of soil concentration.

  10. Gamma radiation effects on phenolics, antioxidants activity and in vitro digestion of pistachio ( Pistachia vera) hull

    Science.gov (United States)

    Behgar, M.; Ghasemi, S.; Naserian, A.; Borzoie, A.; Fatollahi, H.

    2011-09-01

    The effect of gamma radiation (10, 20, 30, 40, 50 and 60 kGy) on tannin, total phenolics, antioxidants activity and in vitro digestion of pistachio hulls has been investigated in this study. The possibility of using the radial diffusion method based on software measurement of the rings area has also been investigated in this study. The software based method in radial diffusion method showed a higher r2 (0.995) value when compared to the traditional method. Irradiation reduced the tannin content ( Ppistachio hull extracts but increased the total phenolic content ( Ppistachio hull. Irradiation decreased the digestion rate of the pistachio hull at the dose of 40 kGy when compared to the control. This study showed that gamma irradiation decreased tannin and antioxidants activity of pistachio hull.

  11. First limits on the very-high energy gamma-ray afterglow emission of a fast radio burst. H.E.S.S. observations of FRB 150418

    Science.gov (United States)

    H.E.S.S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Akhperjanian, A. G.; Andersson, T.; Angüner, E. O.; Arakawa, M.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Becker Tjus, J.; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Büchele, M.; Bulik, T.; Capasso, M.; Carr, J.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chalme-Calvet, R.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Chrétien, M.; Coffaro, M.; Colafrancesco, S.; Cologna, G.; Condon, B.; Conrad, J.; Cui, Y.; Davids, I. D.; Decock, J.; Degrange, B.; Deil, C.; Devin, J.; Dewilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O.'c.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Funk, S.; Füßling, M.; Gabici, S.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Gottschall, D.; Goyal, A.; Grondin, M.-H.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holler, M.; Horns, D.; Ivascenko, A.; Iwasaki, H.; Jacholkowska, A.; Jamrozy, M.; Janiak, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jogler, T.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katsuragawa, M.; Katz, U.; Kerszberg, D.; Khangulyan, D.; Khélifi, B.; Kieffer, M.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lefranc, V.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; Nakashima, S.; de Naurois, M.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Öttl, S.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Reimer, A.; Reimer, O.; Renaud, M.; de Los Reyes, R.; Richter, S.; Rieger, F.; Romoli, C.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Saito, S.; Salek, D.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Seglar-Arroyo, M.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Simoni, R.; Sol, H.; Spanier, F.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stycz, K.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tsuji, N.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zabalza, V.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Żywucka, N.; Superb Collaboration; Jankowski, F.; Keane, E. F.; Petroff, E.

    2017-01-01

    Aims: Following the detection of the fast radio burst FRB150418 by the SUPERB project at the Parkes radio telescope, we aim to search for very-high energy gamma-ray afterglow emission. Methods: Follow-up observations in the very-high energy gamma-ray domain were obtained with the H.E.S.S. imaging atmospheric Cherenkov telescope system within 14.5 h of the radio burst. Results: The obtained 1.4 h of gamma-ray observations are presented and discussed. At the 99% C.L. we obtained an integral upper limit on the gamma-ray flux of Φγ(E > 350 GeV) FRB 150418. Conclusions: No hints for high-energy afterglow emission of FRB 150418 were found. Taking absorption on the extragalactic background light into account and assuming a distance of z = 0.492 based on radio and optical counterpart studies and consistent with the FRB dispersion, we constrain the gamma-ray luminosity at 1 TeV to L < 5.1 × 1047 erg/s at 99% C.L.

  12. Bullet scintigraphy: can gamma camera be used for depleted uranium accident measurements?

    International Nuclear Information System (INIS)

    Spaic, R.; Markovic, S.; Pavlovic, S.; Radic, Z.; Pavlovic, R.; Ajdinovic, B.; Baskot, B.; Djurovic, B.

    2002-01-01

    The aim of this study was to see could gamma cameras be used for measurement of internal contamination with depleted uranium. Radioactive waste depleted uranium, which is by-product from the production of enriched fuel for nuclear rectors and weapons now, is used for manufacture bullets, which are used in Iraq, Republic of Srpska and Yugoslavia. In this paper is measured minimum detectable activity (MDA) of gamma cameras for depleted uranium, iodine and technetium. For detection of the depleted uranium are used low energy X-rays, energy of 100 keV with 20% windows width. About 40% of gamma emissions of the depleted uranium are in these limits. Measured MDA activities 50-100 Bq for depleted uranium, iodine and technetium are about then times more then same for WBC (5 Bq). Gamma cameras can be used for relatively measurement of depleted uranium activity, what can be used for absorbed dose estimation. Detection of low level internal contamination with depleted uranium can be done with gamma cameras. (authors)

  13. 40 CFR Table 1 to Subpart Nnnnnn... - HAP Emissions Sources

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 14 2010-07-01 2010-07-01 false HAP Emissions Sources 1 Table 1 to Subpart NNNNNN of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...: Chromium Compounds Pt. 63, Subpt. NNNNNN, Table 1 Table 1 to Subpart NNNNNN of Part 63—HAP Emissions...

  14. Standardization of 40 K by liquid scintillation counting. Determination of the half-life

    International Nuclear Information System (INIS)

    Grau Carles, A.; Grau Malonda, A.

    1997-01-01

    The relative abundance of the natural radioisotope ''40 K in environmental samples frequently generates interferences in low activity measurements. In the present study we propose the determination of ''40 K by the CIEMAT/NIST method. On this context, the verification of ''40 K half-life is required. We present a half-life value obtained by liquid scintillation counting in excellent agreement with those reported in the literature. (Author)

  15. Effect of gamma irradiation on nano polymer poly aniline

    International Nuclear Information System (INIS)

    Chan Yan Yhee

    2012-01-01

    Poly aniline (PANI) is a conductor polymer that investigated by a lot of researchers which display unique electric characteristic and widely applications. The objective in this research is to see the effect of gamma irradiation on PANI by using microemulsion method. Cation surfactant, cetyltrimethylammonium bromide, (CTAB) use in microemulsion method for dissolve aniline with distilled water. Mixture of aniline, ammonium persulfate (APS) as oxidizing agent and hydrochloric acid (HCL) into aqueous CTAB and magnetic bar stirrer applied at temperature of 3 degree Celsius for 3 hours to form PANI. The washing is done by using distilled water and ethanol to purify PANI. After washing the PANI are categories in two group, PANI aqueous solution and PANI powder. PANI aqueous solution irradiated with gamma irradiation from 0 kGy to 100 kGy doses in 10 kGy intervals while PANI powder are dried in oven before irradiated with gamma irradiation with same doses as PANI aqueous solution. These aqueous solution products are characterized by ultraviolet absorption spectroscopy (UV-Vis) which shows the electron transition π - π * and Microscope Electron Transmission (TEM) for morforlogy of PANI nanoparticles while PANI powder are characterized using Spectroscopy Fourier Transformation Intra-Red (FTIR) for the functional group, X-Ray Diffraction (XRD) to determine the crystalline peak and Field Emission Scanning Electron Microscope (FESEM) for morphology PANI nanoparticles. The effect of gamma irradiation nanoparticles are PANI aqueous solution produce aggregation and changing of PANI nanoparticles sizes while PANI powder produce fractures and distortion on PANI nanoparticles. (author)

  16. Soil-to-plant transfer factors of natural radionuclides (226Ra and 40K) in selected Thai medicinal plants.

    Science.gov (United States)

    Saenboonruang, Kiadtisak; Phonchanthuek, Endu; Prasandee, Kamonkhuan

    2018-04-01

    A soil-to-plant transfer factor (TF) is an important parameter that could be used to estimate radionuclides levels in medicinal plants. This work reports concentrations of natural radionuclides ( 226 Ra and 40 K) and TFs in six Thai medicinal plants grown in central Thailand using an HPGe gamma ray spectrometer. Either root, leaf, or flower parts of each medicinal plant were selected for use in the investigation according to their practical uses in traditional medicine. The results showed that due to K being essential in plants, 40 K had higher arithmetic means of activity concentrations and geometric means of TFs (geometric standard deviations in parentheses) of 610 ± 260 Bq kg -1 dry weight (DW) and 2.0 (1.4), respectively, than 226 Ra, which had the activity concentrations and TFs of 4.8 ± 2.6 Bq kg -1 DW and 0.17 (1.8), respectively. The results also showed that the leaves of medicinal plants had higher activity concentrations and TFs than root and flower parts, probably due to higher metabolic activities in leaves. Furthermore, there was good agreement between the results from the current work and other similar reports on medicinal plants. The information obtained from this work could strengthen knowledge of natural radionuclides in plants and particularly increase available TF data on Thai medicinal plants. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Measurement of the CKM angle $\\gamma$ using $B^\\pm\\to DK^\\pm$ with $D\\to K_\\text{S}^0\\pi^+\\pi^-$, $K_\\text{S}^0K^+K^-$ decays

    CERN Document Server

    Aaij, Roel; LHCb Collaboration; Adinolfi, Marco; Aidala, Christine Angela; Ajaltouni, Ziad; Akar, Simon; Albicocco, Pietro; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Alfonso Albero, Alejandro; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Andreassi, Guido; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Archilli, Flavio; d'Argent, Philippe; Arnau Romeu, Joan; Artamonov, Alexander; Artuso, Marina; Arzymatov, Kenenbek; Aslanides, Elie; Atzeni, Michele; Bachmann, Sebastian; Back, John; Baker, Sophie; Balagura, Vladislav; Baldini, Wander; Baranov, Alexander; Barlow, Roger; Barsuk, Sergey; Barter, William; Baryshnikov, Fedor; Batozskaya, Varvara; Batsukh, Baasansuren; Battista, Vincenzo; Bay, Aurelio; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Beiter, Andrew; Bel, Lennaert; Beliy, Nikita; Bellee, Violaine; Belloli, Nicoletta; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Beranek, Sarah; Berezhnoy, Alexander; Bernet, Roland; Berninghoff, Daniel; Bertholet, Emilie; Bertolin, Alessandro; Betancourt, Christopher; Betti, Federico; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bezshyiko, Iaroslava; Bhasin, Srishti; Bhom, Jihyun; Bian, Lingzhu; Bifani, Simone; Billoir, Pierre; Birnkraut, Alex; Bizzeti, Andrea; Bjørn, Mikkel; Blago, Michele Piero; Blake, Thomas; Blanc, Frederic; Blusk, Steven; Bobulska, Dana; Bocci, Valerio; Boente Garcia, Oscar; Boettcher, Thomas; Bondar, Alexander; Bondar, Nikolay; Borghi, Silvia; Borisyak, Maxim; Borsato, Martino; Bossu, Francesco; Boubdir, Meriem; Bowcock, Themistocles; Bozzi, Concezio; Braun, Svende; Brodski, Michael; Brodzicka, Jolanta; Brundu, Davide; Buchanan, Emma; Buonaura, Annarita; Burr, Christopher; Bursche, Albert; Buytaert, Jan; Byczynski, Wiktor; Cadeddu, Sandro; Cai, Hao; Calabrese, Roberto; Calladine, Ryan; Calvi, Marta; Calvo Gomez, Miriam; Camboni, Alessandro; Campana, Pierluigi; Campora Perez, Daniel Hugo; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Cattaneo, Marco; Cavallero, Giovanni; Cenci, Riccardo; Chamont, David; Chapman, Matthew George; Charles, Matthew; Charpentier, Philippe; Chatzikonstantinidis, Georgios; Chefdeville, Maximilien; Chekalina, Viktoriia; Chen, Chen; Chen, Shanzhen; Chitic, Stefan-Gabriel; Chobanova, Veronika; Chrzaszcz, Marcin; Chubykin, Alexsei; Ciambrone, Paolo; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cojocariu, Lucian; Collins, Paula; Colombo, Tommaso; Comerma-Montells, Albert; Contu, Andrea; Coombs, George; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Costa Sobral, Cayo Mar; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Currie, Robert; D'Ambrosio, Carmelo; Da Cunha Marinho, Franciole; Da Silva, Cesar Luiz; Dall'Occo, Elena; Dalseno, Jeremy; Danilina, Anna; Davis, Adam; De Aguiar Francisco, Oscar; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Serio, Marilisa; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Del Buono, Luigi; Delaney, Blaise; Dembinski, Hans Peter; Demmer, Moritz; Dendek, Adam; Derkach, Denis; Deschamps, Olivier; Desse, Fabrice; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Di Nezza, Pasquale; Didenko, Sergey; Dijkstra, Hans; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Douglas, Lauren; Dovbnya, Anatoliy; Dreimanis, Karlis; Dufour, Laurent; Dujany, Giulio; Durante, Paolo; Durham, John Matthew; Dutta, Deepanwita; Dzhelyadin, Rustem; Dziewiecki, Michal; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; Ely, Scott; Ene, Alexandru; Escher, Stephan; Esen, Sevda; Evans, Timothy; Falabella, Antonio; Farley, Nathanael; Farry, Stephen; Fazzini, Davide; Federici, Luca; Fernandez, Gerard; Fernandez Declara, Placido; Fernandez Prieto, Antonio; Ferrari, Fabio; Ferreira Lopes, Lino; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fini, Rosa Anna; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fleuret, Frederic; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Franco Lima, Vinicius; Frank, Markus; Frei, Christoph; Fu, Jinlin; Funk, Wolfgang; Färber, Christian; Féo Pereira Rivello Carvalho, Mauricio; Gabriel, Emmy; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; Garcia Martin, Luis Miguel; Garcia Plana, Beatriz; García Pardiñas, Julián; Garra Tico, Jordi; Garrido, Lluis; Gascon, David; Gaspar, Clara; Gavardi, Laura; Gazzoni, Giulio; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Gerstel, Dawid; Ghez, Philippe; Gianì, Sebastiana; Gibson, Valerie; Girard, Olivier Göran; Giubega, Lavinia-Helena; Gizdov, Konstantin; Gligorov, Vladimir; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gorelov, Igor Vladimirovich; Gotti, Claudio; Govorkova, Ekaterina; Grabowski, Jascha Peter; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greim, Roman; Griffith, Peter; Grillo, Lucia; Gruber, Lukas; Gruberg Cazon, Barak Raimond; Grünberg, Oliver; Gu, Chenxi; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Göbel, Carla; Hadavizadeh, Thomas; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hamilton, Brian; Han, Xiaoxue; Hancock, Thomas Henry; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Thomas; Hasse, Christoph; Hatch, Mark; He, Jibo; Hecker, Malte; Heinicke, Kevin; Heister, Arno; Hennessy, Karol; Henry, Louis; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hilton, Martha; Hopchev, Plamen Hristov; Hu, Wenhua; Huang, Wenqian; Huard, Zachary; Hulsbergen, Wouter; Humair, Thibaud; Hushchyn, Mikhail; Hutchcroft, David; Ibis, Philipp; Idzik, Marek; Ilten, Philip; Ivshin, Kuzma; Jacobsson, Richard; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; Jiang, Feng; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Karacson, Matthias; Kariuki, James Mwangi; Karodia, Sarah; Kazeev, Nikita; Kecke, Matthieu; Keizer, Floris; Kelsey, Matthew; Kenzie, Matthew; Ketel, Tjeerd; Khairullin, Egor; Khanji, Basem; Khurewathanakul, Chitsanu; Kim, Kyung Eun; Kirn, Thomas; Klaver, Suzanne; Klimaszewski, Konrad; Klimkovich, Tatsiana; Koliiev, Serhii; Kolpin, Michael; Kopecna, Renata; Koppenburg, Patrick; Kostiuk, Igor; Kotriakhova, Sofia; Kozeiha, Mohamad; Kravchuk, Leonid; Kreps, Michal; Kress, Felix Johannes; Krokovny, Pavel; Krupa, Wojciech; Krzemien, Wojciech; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kuonen, Axel Kevin; Kvaratskheliya, Tengiz; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lancierini, Davide; Lanfranchi, Gaia; Langenbruch, Christoph; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; Leflat, Alexander; Lefrançois, Jacques; Lefèvre, Regis; Lemaitre, Florian; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Pei-Rong; Li, Tenglin; Li, Zhuoming; Liang, Xixin; Likhomanenko, Tatiana; Lindner, Rolf; Lionetto, Federica; Lisovskyi, Vitalii; Liu, Xuesong; Loh, David; Loi, Angelo; Longstaff, Iain; Lopes, Jose; Lovell, George Holger; Lucchesi, Donatella; Lucio Martinez, Miriam; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Lusiani, Alberto; Lyu, Xiao-Rui; Machefert, Frederic; Maciuc, Florin; Macko, Vladimir; Mackowiak, Patrick; Maddrell-Mander, Samuel; Maev, Oleg; Maguire, Kevin; Maisuzenko, Dmitrii; Majewski, Maciej Witold; Malde, Sneha; Malecki, Bartosz; Malinin, Alexander; Maltsev, Timofei; Manca, Giulia; Mancinelli, Giampiero; Marangotto, Daniele; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marinangeli, Matthieu; Marino, Pietro; Marks, Jörg; Martellotti, Giuseppe; Martin, Morgan; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Massafferri, André; Matev, Rosen; Mathad, Abhijit; Mathe, Zoltan; Matteuzzi, Clara; Mauri, Andrea; Maurice, Emilie; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McNab, Andrew; McNulty, Ronan; Mead, James Vincent; Meadows, Brian; Meaux, Cedric; Meier, Frank; Meinert, Nis; Melnychuk, Dmytro; Merk, Marcel; Merli, Andrea; Michielin, Emanuele; Milanes, Diego Alejandro; Millard, Edward James; Minard, Marie-Noelle; Minzoni, Luca; Mitzel, Dominik Stefan; Mogini, Andrea; Molina Rodriguez, Josue; Mombächer, Titus; Monroy, Igancio Alberto; Monteil, Stephane; Morandin, Mauro; Morello, Gianfranco; Morello, Michael Joseph; Morgunova, Olga; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Mulder, Mick; Murphy, Colm Harold; Murray, Donal; Müller, Dominik; Müller, Janine; Müller, Katharina; Müller, Vanessa; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nandi, Anita; Nanut, Tara; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Thi Dung; Nguyen-Mau, Chung; Nieswand, Simon; Niet, Ramon; Nikitin, Nikolay; Nogay, Alla; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Oldeman, Rudolf; Onderwater, Gerco; Ossowska, Anna; Otalora Goicochea, Juan Martin; Owen, Patrick; Oyanguren, Maria Aranzazu; Pais, Preema Rennee; Palano, Antimo; Palutan, Matteo; Panshin, Gennady; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parker, William; Parkes, Christopher; Passaleva, Giovanni; Pastore, Alessandra; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Pereima, Dmitrii; Perret, Pascal; Pescatore, Luca; Petridis, Konstantinos; Petrolini, Alessandro; Petrov, Aleksandr; Petrucci, Stefano; Petruzzo, Marco; Pietrzyk, Boleslaw; Pietrzyk, Guillaume; Pikies, Malgorzata; Pili, Martina; Pinci, Davide; Pinzino, Jacopo; Pisani, Flavio; Piucci, Alessio; Placinta, Vlad-Mihai; Playfer, Stephen; Plews, Jonathan; Plo Casasus, Maximo; Polci, Francesco; Poli Lener, Marco; Poluektov, Anton; Polukhina, Natalia; Polyakov, Ivan; Polycarpo, Erica; Pomery, Gabriela Johanna; Ponce, Sebastien; Popov, Alexander; Popov, Dmitry; Poslavskii, Stanislav; Potterat, Cédric; Price, Eugenia; Prisciandaro, Jessica; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Pullen, Hannah Louise; Punzi, Giovanni; Qian, Wenbin; Qin, Jia-Jia; Quagliani, Renato; Quintana, Boris; Rachwal, Bartlomiej; Rademacker, Jonas; Rama, Matteo; Ramos Pernas, Miguel; Rangel, Murilo; Ratnikov, Fedor; Raven, Gerhard; Ravonel Salzgeber, Melody; Reboud, Meril; Redi, Federico; Reichert, Stefanie; dos Reis, Alberto; Reiss, Florian; Remon Alepuz, Clara; Ren, Zan; Renaudin, Victor; Ricciardi, Stefania; Richards, Sophie; Rinnert, Kurt; Robbe, Patrick; Robert, Arnaud; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Lopez, Jairo Alexis; Roehrken, Markus; Rogozhnikov, Alexey; Roiser, Stefan; Rollings, Alexandra Paige; Romanovskiy, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rudolph, Matthew Scott; Ruf, Thomas; Ruiz Vidal, Joan; Saborido Silva, Juan Jose; Sagidova, Naylya; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Gras, Cristina; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santimaria, Marco; Santovetti, Emanuele; Sarpis, Gediminas; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saur, Miroslav; Savrina, Darya; Schael, Stefan; Schellenberg, Margarete; Schiller, Manuel; Schindler, Heinrich; Schmelling, Michael; Schmelzer, Timon; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schreiner, HF; Schubiger, Maxime; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sepulveda, Eduardo Enrique; Sergi, Antonino; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shmanin, Evgenii; Siddi, Benedetto Gianluca; Silva Coutinho, Rafael; Silva de Oliveira, Luiz Gustavo; Simi, Gabriele; Simone, Saverio; Skidmore, Nicola; Skwarnicki, Tomasz; Smeaton, John Gordon; Smith, Eluned; Smith, Iwan Thomas; Smith, Mark; Soares, Marcelo; Soares Lavra, Lais; Sokoloff, Michael; Soler, Paul; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Stefko, Pavol; Stefkova, Slavomira; Steinkamp, Olaf; Stemmle, Simon; Stenyakin, Oleg; Stepanova, Margarita; Stevens, Holger; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Stramaglia, Maria Elena; Straticiuc, Mihai; Straumann, Ulrich; Strokov, Sergey; Sun, Jiayin; Sun, Liang; Swientek, Krzysztof; Syropoulos, Vasileios; Szumlak, Tomasz; Szymanski, Maciej Pawel; T'Jampens, Stephane; Tang, Zhipeng; Tayduganov, Andrey; Tekampe, Tobias; Tellarini, Giulia; Teubert, Frederic; Thomas, Eric; van Tilburg, Jeroen; Tilley, Matthew James; Tisserand, Vincent; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Tou, Da Yu; Tourinho Jadallah Aoude, Rafael; Tournefier, Edwige; Traill, Murdo; Tran, Minh Tâm; Trisovic, Ana; Tsaregorodtsev, Andrei; Tully, Alison; Tuning, Niels; Ukleja, Artur; Usachov, Andrii; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagner, Alexander; Vagnoni, Vincenzo; Valassi, Andrea; Valat, Sebastien; Valenti, Giovanni; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vecchi, Stefania; van Veghel, Maarten; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Venkateswaran, Aravindhan; Verlage, Tobias Anton; Vernet, Maxime; Vesterinen, Mika; Viana Barbosa, Joao Vitor; Vieira, Daniel; Vieites Diaz, Maria; Viemann, Harald; Vilasis-Cardona, Xavier; Vitkovskiy, Arseniy; Vitti, Marcela; Volkov, Vladimir; Vollhardt, Achim; Voneki, Balazs; Vorobyev, Alexey; Vorobyev, Vitaly; de Vries, Jacco; Vázquez Sierra, Carlos; Waldi, Roland; Walsh, John; Wang, Jianchun; Wang, Mengzhen; Wang, Yilong; Wang, Zhenzi; Ward, David; Wark, Heather Mckenzie; Watson, Nigel; Websdale, David; Weiden, Andreas; Weisser, Constantin; Whitehead, Mark; Wicht, Jean; Wilkinson, Guy; Wilkinson, Michael; Williams, Ifan; Williams, Mark Richard James; Williams, Mike; Williams, Timothy; Wilson, Fergus; Wimberley, Jack; Winn, Michael Andreas; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wyllie, Kenneth; Xiao, Dong; Xie, Yuehong; Xu, Ao; Xu, Menglin; Xu, Qingnian; Xu, Zehua; Xu, Zhirui; Yang, Zhenwei; Yang, Zishuo; Yao, Yuezhe; Yeomans, Lauren Emma; Yin, Hang; Yu, Jiesheng; Yuan, Xuhao; Yushchenko, Oleg; Zarebski, Kristian Alexander; Zavertyaev, Mikhail; Zhang, Dongliang; Zhang, Liming; Zhang, Wen Chao; Zhang, Yanxi; Zhelezov, Alexey; Zheng, Yangheng; Zhu, Xianglei; Zhukov, Valery; Zonneveld, Jennifer Brigitta; Zucchelli, Stefano

    2018-01-01

    A binned Dalitz plot analysis of $B^\\pm \\to D K^\\pm$ decays, with $D\\to K_\\text{S}^0\\pi^+\\pi^-$ and $D\\to K_\\text{S}^0K^+K^-$, is used to perform a measurement of the CP-violating observables $x_{\\pm}$ and $y_{\\pm}$, which are sensitive to the Cabibbo-Kobayashi-Maskawa angle $\\gamma$. The analysis is performed without assuming any $D$ decay model, through the use of information on the strong-phase variation over the Dalitz plot from the CLEO collaboration. Using a sample of proton-proton collision data collected with the LHCb experiment in 2015 and 2016, and corresponding to an integrated luminosity of 2.0$\\,\\text{fb}^{-1}$, the values of the CP violation parameters are found to be $x_- = ( 9.0 \\pm 1.7 \\pm 0.7 \\pm 0.4) \\times 10^{-2}$, $y_- = ( 2.1 \\pm 2.2 \\pm 0.5 \\pm 1.1) \\times 10^{-2}$, $x_+ = (- 7.7 \\pm 1.9 \\pm 0.7 \\pm 0.4) \\times 10^{-2}$, and $y_+ = (- 1.0 \\pm 1.9 \\pm 0.4 \\pm 0.9) \\times 10^{-2}$. The first uncertainty is statistical, the second is systematic, and the third is due to the uncertainty on ...

  18. Fluorine determination in human and animal bones by particle-induced gamma-ray emission

    International Nuclear Information System (INIS)

    Sastri, Chaturvedula S.; Hoffmann, Peter; Ortner, Hugo M.; Iyengar, Venkatesh; Blondiaux, Gilbert; Tessier, Yves; Petri, Hermann; Aras, Namik K.; Zaichick, Vladimir

    2002-01-01

    Fluorine was determined in the iliac crest bones of patients and in ribs collected from postmortem investigations by particle-induced gamma-ray emission based on the 19 F(p,pγ) 19 F reaction, using 20/2.5 MeV protons. The results indicate that for 68% of the human samples the F concentration is in the range 500-1999 μg g -1 . For comparison purposes fluorine was also determined in some animal bones; in some animal tissues lateral profiles of fluorine were measured. (abstract)

  19. Development and applications of k0 based NAA and prompt gamma-ray NAA methods at BARC

    International Nuclear Information System (INIS)

    Acharya, R.; Nair, A.G.C.; Sudarshan, K.; Goswami, A.; Reddy, A.V.R.

    2008-01-01

    A summary of k 0 -based R and D work on neutron activation analysis (NAA), internal mono standard NAA (IM-NAA) and prompt gamma-ray NAA (PGNAA) is presented. The k 0 -based NAA was standardized by characterizing irradiation sites of research reactors, validated using reference materials and applied to samples of different origin. Recently IM-NAA method was developed, validated for small and large size samples and applied for the analysis of large size as well as non-standard geometry samples. Studies on PGNAA included characterization of neutron beam, determinations of detection efficiency and prompt k 0 -factors, and analytical applications. (author)

  20. APLIKASI PENSILBARIS1.2 UNTUK DESAIN KESELAMATAN IRADIATOR GAMMA BATAN 500K

    Directory of Open Access Journals (Sweden)

    M.S. Pudjijanto

    2015-04-01

    Full Text Available Aspek keselamatan penggunaaan radiasi gamma, khususnya penggunaan iradiator gamma perlu ditekankan untuk menjamin keselamatan personil maupun keselamatan lingkungan. Keselamatan radiasi pekerja diperhitungkan pada saat fasilitas iradiasi beroperasi normal dan ketika sedang dilakukan bongkar-muat sumber radiasi dan perawatan/perbaikan fasilitas dengan sumber radiasi berada di dalam kolam penyimpan atau di rak khusus penyimpan sumber. Jenis dan tebal dinding beton ruang papar yang sekaligus berfungsi sebagai perisai radiasi perlu dipertimbangkan, agar paparan radiasi di lingkungan fasilitas iradiator ini memenuhi kriteria keselamatan radiasi yang ditetapkan BAPETEN. Perhitungan dilakukan dengan menggunakan PensilBaris1.2 dengan teknik integrasi kernel titik dan sebagai pembanding digunakan program MCNP5 dengan teknik Monte Carlo. Fasilitas iradiator gamma inovatif yang akan didesain berdimensi panjang 13 m, lebar 6 m dan tinggi 4 m. Radiasi gamma bersumber dari 36-52 batang Cobalt-60 beraktivitas total 500 kCi yang disusun tegak berjajar yang berjarak sama dalam sepasang rak sejajar bertingka dua dengan panjang 135 cm dan tinggi 100 cm. Jarak pisang antara sepasang rak sumber gamma ditetapkan 120 cm. Hasil perhitungan program PensilBaris1.2 untuk dinding beton dengan kerapatan 2,45 g/cm3 berturut-turut memberikan 141,6; 164,4 dan 154,9 cm dan program MCNP5 berturut-turut memberikan ketebalan 145, 155 dan 140 cm. Perbedaan hasil dari kedua tool ini, selain disebabkan oleh teknik dan metode komputasi yang berbeda, disebabkan karena adanya perbedaan pustaka data tampang interaksi foton dengan materi dan faktor bangkit dosis yang digunakan. Hasil perhitungan menggunakan PensilBaris1.2 dengan kerapatan 2,35 g/cm3 memberikan tebal dinding beton dalam arah memanjang, melebar dan meninggi berturut-turut 147,4; 170,7 dan 161,4 cm. Kedalaman benam minimal ujung atas sumber dari permukaan air kolam menggunakan PensilBaris1.2 sebesar 4,85 meter untuk laju

  1. Microbial analysis and survey test of gamma-irradiated freeze-dried fruits for patient's food

    Science.gov (United States)

    Park, Jae-Nam; Sung, Nak-Yun; Byun, Eui-Hong; Byun, Eui-Baek; Song, Beom-Seok; Kim, Jae-Hun; Lee, Kyung-A.; Son, Eun-Joo; Lyu, Eun-Soon

    2015-06-01

    This study examined the microbiological and organoleptic qualities of gamma-irradiated freeze-dried apples, pears, strawberries, pineapples, and grapes, and evaluated the organoleptic acceptability of the sterilized freeze-dried fruits for hospitalized patients. The freeze-dried fruits were gamma-irradiated at 0, 1, 2, 3, 4, 5, 10, 12, and 15 kGy, and their quality was evaluated. Microorganisms were not detected in apples after 1 kGy, in strawberries and pears after 4 kGy, in pineapples after 5 kGy, and in grapes after 12 kGy of gamma irradiation. The overall acceptance score, of the irradiated freeze-dried fruits on a 7-point scale at the sterilization doses was 5.5, 4.2, 4.0, 4.1, and 5.1 points for apples, strawberries, pears, pineapples, and grapes, respectively. The sensory survey of the hospitalized cancer patients (N=102) resulted in scores of 3.8, 3.7, 3.9, 3.9, and 3.7 on a 5-point scale for the gamma-irradiated freeze-dried apples, strawberries, pears, pineapples, and grapes, respectively. The results suggest that freeze-dried fruits can be sterilized with a dose of 5 kGy, except for grapes, which require a dose of 12 kGy, and that the organoleptic quality of the fruits is acceptable to immuno-compromised patients. However, to clarify the microbiological quality and safety of freeze-dried fruits should be verified by plating for both aerobic and anaerobic microorganisms.

  2. Aging of magnesium stearate under high doses gamma irradiation and oxidative conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lebeau, D.; Beuvier, L.; Cornaton, M. [CEA, DEN, DPC, SECR, LRMO, F-91191 Gif-sur-Yvette (France); Miserque, F. [CEA, DEN, DPC, SCCME, LECA, F-91191 Gif-sur-Yvette (France); Tabarant, M. [CEA, DEN, DPC, SEARS, LISL, F-91191 Gif-sur-Yvette (France); Esnouf, S. [CEA, DEN, DPC, SECR, LRMO, F-91191 Gif-sur-Yvette (France); Ferry, M., E-mail: muriel.ferry@cea.fr [CEA, DEN, DPC, SECR, LRMO, F-91191 Gif-sur-Yvette (France)

    2015-05-15

    Highlights: • Magnesium stearate was radio-oxidized at very high doses using gamma-rays. • H{sub 2} emission was estimated as a function of the integrated dose. • Modifications in the organic solid were followed as a function of the integrated dose. • A non-exhaustive degradation mechanism of magnesium stearate was proposed. - Abstract: In nuclear waste packages conditioning processes, magnesium stearate is widely used because of its high lubricating properties. For safety purposes, the radiolytic degradation of these organic materials has to be better understood to be able to predict their aging in repository conditions. This study reports the radiolytic degradation of magnesium stearate, using gamma-rays at room temperature and under air. Modifications were followed using different analytical tools (XPS, ATR-FTIR, ICP-AES, ATG and mass spectrometry). It has been observed that molecules mainly formed up to 1000 kGy of gamma irradiation dose under radio-oxidation are alkanes, hydroperoxides, double bonds in the aliphatic chain, carboxylates with aliphatic chain shorter than the one of stearate and ketones. At a dose of 4000 kGy, dicarboxylic acids are observed: the formation of these molecules needs a dose of at least 1000 kGy to be created under radio-oxidation. These observations allow us to propose a non-exhaustive degradation mechanism of magnesium stearate under gamma-irradiation at room temperature and under air.

  3. 40 CFR 75.83 - Calculation of Hg mass emissions and heat input rate.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Calculation of Hg mass emissions and... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTINUOUS EMISSION MONITORING Hg Mass Emission Provisions § 75.83 Calculation of Hg mass emissions and heat input rate. The owner or operator shall calculate Hg mass emissions...

  4. Determination of uranium and thorium using gamma spectrometry: a pilot study

    Science.gov (United States)

    Olivares, D. M. M.; Koch, E. S.; Guevara, M. V. M.; Velasco, F. G.

    2018-03-01

    This paper presents the results of a pilot experiment aimed at standardizing procedures for the CPqCTR/UESC Gamma Spectrometry Laboratory (LEG) for the quantification of natural radioactive elements in solid environmental samples. The concentrations of 238U, 232Th and 40K in two sediment matrix belonging to the Caetité region were determined, by using the absolute method with uncertainties about 5%. The results were obtained using gamma spectrometry with a high-resolution p-type HPGe detector. As a closure, the absorbed dose, radium equivalent activity and the annual effective dose were calculated.

  5. System for gamma-gamma formation density logging while drilling

    International Nuclear Information System (INIS)

    Paske, W.C.

    1991-01-01

    The patent relates to a system for logging subterranean formations for the determination of formation density by using gamma radiation. Gamma ray source and detection means are disposed within a housing adapted for positioning within a borehole for the emission and detection of gamma rays propagating through earth formations and borehole drilling fluid. The gamma ray detection means comprises first and second gamma radiation sensors geometrically disposed within the housing, the same longitudinal distance from the gamma ray source and diametrically opposed in a common plane. A formation matrix density output signal is produced in proportion to the output signal from each of the gamma ray sensors and in conjunction with certain constants established by the geometrical configuration of the sensors relative to the gamma ray source and the borehole diameter. Formation density is determined without regard to the radial position of the logging probe within the borehole in a measuring while drilling mode. 6 figs

  6. Measurement of the high-energy gamma-ray emission from the Moon with the Fermi Large Area Telescope

    CERN Document Server

    Ackermann, M.; Albert, A.; Atwood, W. B.; Baldini, L.; Barbiellini, G.; Bastieri, D.; Bellazzini, R.; Bissaldi, E.; Blandford, R. D.; Bonino, R.; Bottacini, E.; Bregeon, J.; Bruel, P.; Buehler, R.; Caliandro, G. A.; Cameron, R. A.; Caragiulo, M.; Caraveo, P.A.; Cavazzuti, E.; Cecchi, C.; Chekhtman, A.; Chiang, J.; Chiaro, G.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Costanza, F.; Cuoco, A.; Cutini, S.; D'Ammando, F.; de Angelis, A.; de Palma, F.; Desiante, R.; Digel, S.W.; Di Venere, L.; Drell, P.S.; Favuzzi, C.; Fegan, S.J.; Focke, W.B.; Franckowiak, A.; Funk, S.; Fusco, P.; Gargano, F.; Gasparrini, D.; Giglietto, N.; Giordano, F.; Giroletti, M.; Glanzman, T.; Godfrey, G.; Grenier, I. A.; Grove, J.E.; Guiriec, S.; Harding, A. K.; Hewitt, J. W.; Horan, D.; Hou, X.; Iafrate, G.; Jóhannesson, G.; Kamae, T.; Kuss, M.; Larsson, S.; Latronico, L.; Li, J.; Li, L.; Longo, F.; Loparco, F.; Lovellette, M.N.; Lubrano, P.; Magill, J.; Maldera, S.; Manfreda, A.; Mayer, M.; Mazziotta, M.N.; Michelson, P.F.; Mitthumsiri, W.; Mizuno, T.; Monzani, M.E.; Morselli, A.; Murgia, S.; Nuss, E.; Omodei, N.; Orlando, E.; Ormes, J.F.; Paneque, D.; Perkins, J. S.; Pesce-Rollins, M.; Petrosian, V.; Piron, F.; Pivato, G.; Rainò, S.; Rando, R.; Razzano, M.; Reimer, A.; Reimer, O.; Sgrò, C.; Reposeur, T.; Siskind, E.J.; Spada, F.; Spandre, G.; Spinelli, P.; Takahashi, H.; Thayer, J.B.; Thompson, D.J.; Tibaldo, L.; Torres, D. F.; Tosti, G.; Troja, E.; Vianello, G.; Winer, B. L.; Wood, K. S.; Yassine, M.; Cerutti, F.; Ferrari, A.; Sala, P.R.

    2016-01-01

    We have measured the gamma-ray emission spectrum of the Moon using the data collected by the Large Area Telescope onboard the Fermi satellite during its first 7 years of operation, in the energy range from 30 MeV up to a few GeV. We have also studied the time evolution of the flux, finding a correlation with the solar activity. We have developed a full Monte Carlo simulation describing the interactions of cosmic rays with the lunar surface. The results of the present analysis can be explained in the framework of this model, where the production of gamma rays is due to the interactions of cosmic-ray proton and helium nuclei with the surface of the Moon. Finally, we have used our simulation to derive the cosmic-ray proton and helium spectra near Earth from the Moon gamma-ray data.

  7. The experiments of high power electron beam emission by the K-9M-57 and K-9M-58 rockets

    International Nuclear Information System (INIS)

    Kaneko, Osamu; Sasaki, Susumu; Yamori, Akira; Hagiwara, Michinobu; Kawashima, Nobuki

    1977-01-01

    Active experiments have been conducted to obtain the precise picture of the ionosphere and magnetosphere. As the turbulence source of the active experiment by the authors, electron beam was employed, and the variation of the rocket potential, wave excitation and turbulence of peripheral plasma were investigated. The rated voltage and current of the present electron gun were 6 kV and 500 mA, respectively. The Langmuir probe, floating probe, optical detector and wave receiver were used for the measurement of various phenomena associated with electron beam emission. The experimental data on the voltage-current characteristics of the electron gun, the rocket potential, total light emission and plasma density and temperature were obtained by the K-9M-57 and K-9M-58 rockets. (Yoshimori, M.)

  8. A preliminary study on 226Ra, 232Th, 40K and 137Cs activity concentrations in vegetables and fruits frequently consumed by inhabitants of Elazig Region, Turkey

    International Nuclear Information System (INIS)

    Cumhur Canbazoglu; Mahmut Dogru

    2013-01-01

    Determining radioactivity levels in foodstuffs is of great importance for the protection of human health. In addition, the literature includes few studies related to this subject in Turkey. In this study, gamma spectroscopic system was used in order to measure 226 Ra, 232 Th, 40 K and 137 Cs activity concentrations in vegetables and fruits produced in Elazig( Region. The average activity concentrations in vegetables was calculated as 0.64 ± 0.26 Bq kg -1 for 226 Ra, 0.65 ± 0.14 Bq kg -1 for 232 Th, 13.98 ± 1.22 Bq kg -1 for 40 K, and 0.54 ± 0.04 Bq kg -1 for 137 Cs. The average activity concentrations in fruits were 1.52 ± 0.34, 0.98 ± 0.23, 18.66 ± 1.13 and 0.59 ± 0.16 Bq kg -1 , respectively for 226 Ra, 232 Th, 40 K and 137 Cs. Total committed effective dose value was determined as 20 and 30.55 μSv y -1 , respectively for vegetables and fruits. The findings were compared with previous data reported for Turkey and other regions of the world. (author)

  9. Single photon emission tomography

    International Nuclear Information System (INIS)

    Buvat, Irene

    2011-09-01

    The objective of this lecture is to present the single photon emission computed tomography (SPECT) imaging technique. Content: 1 - Introduction: anatomic, functional and molecular imaging; Principle and role of functional or molecular imaging; 2 - Radiotracers: chemical and physical constraints, main emitters, radioisotopes production, emitters type and imaging techniques; 3 - Single photon emission computed tomography: gamma cameras and their components, gamma camera specifications, planar single photon imaging characteristics, gamma camera and tomography; 4 - Quantification in single photon emission tomography: attenuation, scattering, un-stationary spatial resolution, partial volume effect, movements, others; 5 - Synthesis and conclusion

  10. Examining the nature of very-high-energy gamma-ray emission from the AGN PKS 1222+216 and 3C 279

    Science.gov (United States)

    Price, Sharleen; Brill, Ari; Mukherjee, Reshmi; VERITAS

    2018-01-01

    Blazars are a type of active galactic nuclei (AGN) that emit jets of ionized matter which move towards the Earth at relativistic speeds. In this research we carried out a study of two objects, 3C 279 and PKS 1222+216, which belong to the subset of blazars known as FSRQs (flat spectrum radio quasars), the most powerful TeV-detected sources at gamma-ray energies with bolometric luminosities exceeding 1048 erg/s. The high-energy emission of quasars peaks in the MeV-GeV band, making these sources very rarely detectable in the TeV energy range. In fact, only six FSRQs have ever been detected in this range by very-high-energy gamma-ray telescopes. We will present results from observing campaigns on 3C 279 in 2014 and 2016, when the object was detected in high flux states by Fermi-LAT. Observations include simultaneous coverage with the Fermi-LAT satellite and the VERITAS ground-based array spanning four decades in energy from 100 MeV to 1 TeV. We will also report VERITAS observations of PKS 1222+216 between 2008 and 2017. The detection/non-detection of TeV emission during flaring episodes at MeV energies will further contribute to our understanding of particle acceleration and gamma-ray emission mechanisms in blazar jets.

  11. Determination of specific activity of 226Ra, 232Th and 40K for assessment of environmental hazards

    International Nuclear Information System (INIS)

    Al-Haydari, A.; Al Sharabi, E. S. A.; Al Buhairi, M. H.

    2012-01-01

    Studies have been carried out using gamma-spectrometric techniques to determine the natural radioactivity in some rocks that are used as building materials in Yemen. The concentrations of the natural radionuclides namely 226 Ra, 232 Th and 40 K in the rock samples collected from different rock markets in Yemen have been determined using an NaI(Tl) detector. The concentrations of 226 Ra, 232 Th and 40 K in the studied rock samples range from 22.2 to 88.8 Bq kg -1 , 8.12 to 113.68 Bq kg -1 and 31.3 to 2222.3 Bq kg -1 , respectively. The concentrations of these radionuclides are compared with the typical world values. To evaluate the radiological hazard of the natural radioactivity, the radium equivalent activity, the air absorbed dose rate, the annual effective dose rate, the representative level index and the values of both external and internal hazard indices were evaluated and compared with the internationally approved values. The radium equivalent activity values of all rock samples are lower than the limit of 370 Bq kg -1 except for one sample which is about 413.386. The values of external hazard index (H ex ) and internal hazard index (H in ), absorbed doses in indoor air and the corresponding effective dose equivalents in a typical dwelling are presented. The need for further studies is also discussed. (authors)

  12. Cosmogenic excess of 40K and the flux of fast neutrons in meteorites

    International Nuclear Information System (INIS)

    Stegmann, W.; Begemann, F.

    1975-01-01

    Results are reported of a mass spectrometric investigation of the content and isotopic composition of potassium from the mesosiderite Emery (silicate phase) and the chondrite Elenovka (bulk). Normalized to the Nier value of 39 K/ 41 K = 13.47, the 40 K in Emery (K-content 220 +- 25 ppm) was found to be enriched by (4.03 +- 0.30)%, the potassium from Elenovka (760 +- 50 ppm) to be indistinguishable from terrestrial potassium. Evidence is presented that the excess 40 K in the silicates from Emery (Ca-content 6.06 weight %) has been produced essentially by secondary cosmic ray neutrons via the 40 Ca(n,p)-reaction. The total excess of (2.57 +- 0.39) x 10 14 40 K-atoms/gCa together with the excitation function of the 40 Ca(n,p)-reaction and the neutron flux spectrum of Arnold, Honda and Lal yields a dose of fast neutrons (2 MeV 16 neutrons/cm 2 and an average flux during the cosmic ray exposure age T = (134 +- 12) Myrs of PHI = (17.4 +- 3.1) neutrons/cm 2 sec. (orig./BJ) [de

  13. Lunar occultations for gamma-ray source measurements

    Science.gov (United States)

    Koch, David G.; Hughes, E. B.; Nolan, Patrick L.

    1990-01-01

    The unambiguous association of discrete gamma-ray sources with objects radiating at other wavelengths, the separation of discrete sources from the extended emission within the Galaxy, the mapping of gamma-ray emission from nearby galaxies and the measurement of structure within a discrete source cannot presently be accomplished at gamma-ray energies. In the past, the detection processes used in high-energy gamma-ray astronomy have not allowed for good angular resolution. This problem can be overcome by placing gamma-ray detectors on the moon and using the horizon as an occulting edge to achieve arcsec resolution. For purposes of discussion, this concept is examined for gamma rays above 100 MeV for which pair production dominates the detection process and locally-generated nuclear gamma rays do not contribute to the background.

  14. The rapid decline of the prompt emission in Gamma-Ray Bursts

    CERN Document Server

    Dado, Shlomo; De Rújula, Alvaro

    2008-01-01

    Many gamma ray bursts (GRBs) have been observed with the Burst-Alert and X-Ray telescopes of the SWIFT satellite. The successive `pulses' of these GRBs end with a fast decline and a fast spectral softening, until they are overtaken by another pulse, or the last pulse's decline is overtaken by a less rapidly-varying `afterglow'. The fast decline-phase has been attributed, in the standard fireball model of GRBs, to `high-latitude' synchrotron emission from a collision of two conical shells. This interpretation does not agree with the observed spectral softening. The temporal behaviour and the spectral evolution during the fast-decline phase agree with the predictions of the cannonball model of GRBs.

  15. Effects of gamma irradiation on voltage-dependant NA+ and K+ currents in N1E-115 cells

    International Nuclear Information System (INIS)

    Diserbo, M.; Barbier, M.; Quignard, J.F.

    1998-01-01

    Effects of 15 Gy gamma irradiation on voltage-dependent Na + and K + currents in differentiated N1E-115 cells are studied by using whole cell recording. Only, we observed an activation of Na + currents at a lower threshold. (authors)

  16. Gamma-ray lasers or grasers

    International Nuclear Information System (INIS)

    Wilson, G.V.H.; George, E.P.; Hora, H.

    1976-01-01

    A method is described for controlling the emission and direction of gamma rays from excited nuclei contained in a sample source of suitable geometry having its major axis parallel to the proposed direction of gamma ray emission, comprising subjecting said sample source to thermal or dynamic polarization at temperatures approaching absolute zero in the presence of a strong magnetic field, and when a pulse of coherent gamma radiation is required along said major axis rotating the active nuclei through 90 0 by employing a short pulse of radio frequency oscillations in an auxilliary coil around the sample source

  17. 40 CFR 270.315 - What air emissions control information must I keep at my facility?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 26 2010-07-01 2010-07-01 false What air emissions control information... Facility § 270.315 What air emissions control information must I keep at my facility? If you have air emission control equipment subject to 40 CFR part 264, subpart CC, you must keep the following information...

  18. The transport characteristics of {sup 238}U, {sup 232}Th, {sup 226}Ra, and {sup 40}K in the production cycle of phosphate rock

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Yoon Hee; Lim, Jong Myoung; Ji, Young Yong; Chung, Kun Ho; Kang, Mun Ja [Environmental Radioactivity Assessment Team, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2017-03-15

    Phosphate rock and its by-product are widely used in various industries to produce phosphoric acid, gypsum, gypsum board, and fertilizer. Owing to its high level of natural radioactive nuclides (e.g., 238U and 226Ra), the radiological safety of workers who work with phosphate rock should be systematically managed. In this study, 238U, 232Th, 226Ra, and 40K levels were measured to analyze the transport characteristics of these radionuclides in the production cycle of phosphate rock. Energy dispersive X-ray fluorescence and gamma spectrometry were used to determine the activity of 238U, 232Th, 226Ra, and 40K. To evaluate the extent of secular disequilibrium, the analytical results were compared using statistical methods. Finally, the distribution of radioactivity across different stages of the phosphate rock production cycle was evaluated. The concentration ratios of 226Ra and 238U in phosphate rock were close to 1.0, while those found in gypsum and fertilizer were extremely different, reflecting disequilibrium after the chemical reaction process. The nuclide with the highest activity level in the production cycle of phosphate rock was 40K, and the median 40K activity was 8.972 Bq·g−1 and 1.496 Bq·g−1, respectively. For the 238U series, the activity of 238U and 226Ra was greatest in phosphate rock, and the distribution of activity values clearly showed the transport characteristics of the radionuclides, both for the byproducts of the decay sequences and for their final products. Although the activity of 40K in k-related fertilizer was relatively high, it made a relatively low contribution to the total radiological effect. However, the activity levels of 226Ra and 238U in phosphate rock were found to be relatively high, near the upper end of the acceptable limits. Therefore, it is necessary to systematically manage the radiological safety of workers engaged in phosphate rock processing.

  19. Development of a Reference Database for Particle Induced Gamma Ray Emission (PIGE) Spectroscopy

    International Nuclear Information System (INIS)

    2017-09-01

    Ion beam analysis techniques are non-destructive analytical techniques used to identify the composition and structure of surface layers of materials. The applications of these techniques span environmental control, cultural heritage and conservation, materials and fusion technologies. The particle-induced gamma-ray emission (PIGE) spectroscopy technique in particular, is a powerful tool for detecting light elements in certain depths of surface layers. This publication describes the coordinated effort to measure and compile cross section data relevant to PIGE analysis and make these data available to the community of practice through a comprehensive online database.

  20. Assessment of the geometric coincidence of neutron and gamma probe measurements with solo 40 and CPN 501 B

    International Nuclear Information System (INIS)

    Valles, V.; Guiresse, M.; Tcherbakov, R.

    1989-01-01

    The distance between the gamma and neutron probe measurement centres was determined for the Nardeux Solo 40 and CPN 501 B probes. The centre of the spheres of influence was localized using a water-air interface constituted by a metal cylinder filled with 200 liters of water. For Solo 40, the discrepancy between the two measurement centres was 6 cm. This shift value, which is quite acceptable, does not require any correction for these measurements, even when the soil is heterogeneous. For CNP 501 B, the discrepancy between the neutron and gamma measurement was 11 cm, i.e. nearly twice the value observed with Solo 40. In soils with a marked vertical heterogeneity, it therefore seems preferable to operate a 11 cm shift of the probe between the moisture and density measurements [fr

  1. Observation of galactic gamma radiation

    International Nuclear Information System (INIS)

    Paul, J.A.

    1982-09-01

    A complete and deep survey of the galactic high-energy gamma radiation is now available, thanks to the gamma-ray telescopes on board of the SAS-2 and COS-B spacecrafts. A comparison of the COS-B gamma-ray survey with a fully sampled CO survey together with an Hsub(I) survey is used to show that a simple model, in which uniformly distributed cosmic rays interact with the interstellar gas, can account for almost all the gamma-ray emission observed in the first galactic quadrant. At medium galactic latitudes, it is shown that a relationship exists between the gamma radiation and the interstellar absorption derived from galaxy counts. Therefore gamma rays from the local galactic environment can be used as a valuable probe of the content and structure of the local interstellar medium. The large scale features of the local interstellar gas are revealed, in particular wide concentrations of nearby molecular hydrogen. On a smaller scale, the detection of numerous localized gamma-ray sources focuses the attention on some particular phases of clusters of young and massive stars where diffuse processes of gamma-ray emission may also be at work

  2. 40 CFR 75.34 - Units with add-on emission controls.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Units with add-on emission controls... add-on emission controls. (a) The owner or operator of an affected unit equipped with add-on SO2 and... assurance/quality control program for the unit, required by section 1 in appendix B of this part. To provide...

  3. GAMMA-RAY EMISSION OF ACCELERATED PARTICLES ESCAPING A SUPERNOVA REMNANT IN A MOLECULAR CLOUD

    International Nuclear Information System (INIS)

    Ellison, Donald C.; Bykov, Andrei M.

    2011-01-01

    We present a model of gamma-ray emission from core-collapse supernovae (SNe) originating from the explosions of massive young stars. The fast forward shock of the supernova remnant (SNR) can accelerate particles by diffusive shock acceleration (DSA) in a cavern blown by a strong, pre-SN stellar wind. As a fundamental part of nonlinear DSA, some fraction of the accelerated particles escape the shock and interact with a surrounding massive dense shell producing hard photon emission. To calculate this emission, we have developed a new Monte Carlo technique for propagating the cosmic rays (CRs) produced by the forward shock of the SNR, into the dense, external material. This technique is incorporated in a hydrodynamic model of an evolving SNR which includes the nonlinear feedback of CRs on the SNR evolution, the production of escaping CRs along with those that remain trapped within the remnant, and the broadband emission of radiation from trapped and escaping CRs. While our combined CR-hydro-escape model is quite general and applies to both core collapse and thermonuclear SNe, the parameters we choose for our discussion here are more typical of SNRs from very massive stars whose emission spectra differ somewhat from those produced by lower mass progenitors directly interacting with a molecular cloud.

  4. Individual behavioural predictors of amphetamine-induced emission of 50 kHz vocalization in rats.

    Science.gov (United States)

    Mulvihill, Kevin G; Brudzynski, Stefan M

    2018-05-11

    Measurement of ultrasonic vocalizations (USVs) produced by adult rats represents a highly useful index of emotional arousal. The associations found between 50 kHz USV production and a variety of behavioural and pharmacological protocols increasingly suggests they serve as a marker of positive motivational states. This study used a powerful within-subjects design to investigate the relationships among individual differences in approach to a sweet-food reward, predisposition to emit 50 kHz USVs spontaneously, and 50 kHz USVs emission following acute systemic administration of amphetamine. Both approach motivation and predisposition to call were found to not correlate with each other but did predict 50 kHz USV response to acute amphetamine. These two behavioural phenotypes appear to represent dissociable predictors of acute amphetamine-induced emission of 50 kHz USVs in a non-sensitization paradigm. In contrast to that, a measure of sucrose preference was not found to predict 50 kHz USV emission following amphetamine. Acute amphetamine was also found to increase average sound frequency of emitted USVs and selectively increase the proportion of Trill subtype 50 kHz USVs. Together, these data demonstrate that acute amphetamine-induced 50 kHz USVs in the adult rat represent more than just a univariate motivational state and may represent the product of dissociable subsystems of emotional behavior. Copyright © 2018. Published by Elsevier B.V.

  5. Application of simulated standard spectra in natural radioactivity measurements using gamma spectrometry

    International Nuclear Information System (INIS)

    Narayani, K.; Pant, A.D.; Bhosle, Nitin; Anilkumar, S.; Singh, Rajvir; Pradeepkumar, K.S.

    2014-01-01

    Gamma ray spectrometry is one of the well known analytical techniques for environmental radioactivity measurements. Gamma spectrometer based on NaI(Tl) scintillation detectors is very popular since it offers high efficiency, low cost and case in handling. The poor energy resolution of the NaI(TI) detector is the major disadvantage making tile analysis of complex gamma ray spectra difficult. Least square method or the full spectrum analysis method is widely used for the analysis of complex spectra from scintillation detectors. The main requirement of this method is that the individual standard spectra of all nuclides expected in the complex spectrum in the same measurement geometry must be available. It is not always possible and feasible to have all the standards of nuclides in the desired geometry. A methodology based on the use of simulated standard spectra generated by Monte Carlo technique was proposed for analysis of complex spectra of nuclides. In the present work, for the analysis of 238 U, 233 Th and 40 K in soil samples, the same methodology was applied by using the simulated standard spectra in soil matrix. The details of the simulation method and results analysis of 238 U, 232 Th and 40 K in environmental samples are discussed in this paper

  6. 40 CFR 1045.107 - What are the not-to-exceed emission standards?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false What are the not-to-exceed emission... Emission Standards and Related Requirements § 1045.107 What are the not-to-exceed emission standards? Not...) For engines equipped with a catalyst, use NTE multipliers from the following table across the...

  7. The use of gamma ray data to define the natural radiation environment

    International Nuclear Information System (INIS)

    1990-09-01

    The natural radiation environment is the major source of radiation exposure to man and consists of both internal and external sources. The most significant internal sources are the radioactive elements 40 K and 222 Rn which are taken into the body. The external sources are cosmic rays and naturally occurring radioactive isotopes of the 40 K, 238 U, and 232 Th decay series, some or all of which can be found in the ground, in construction materials, and in the air. This report has been prepared to provide a guide for the use of existing gamma ray survey data to define the natural radiation environment, but will only be concerned with the gamma ray exposure resulting from radiation originating in geological materials. The type of data needed to produce maps are available as a result of airborne, carborne, and ground gamma ray surveys in many parts of the world. Although most of these data were acquired for uranium and other mineral exploration and geological mapping purposes, they can be used to provide background radioactivity information. Standardized survey data can be compiled to produce regional maps of gamma ray air dose rates as well as single radioelement maps. Compilation procedures may use either manual or computer techniques. Although this work will primarily be done as national compilations, it will open the possibility of the compilation of radioelement geochemical maps on a regional and global scale. 48 refs, figs and tabs

  8. Influence of gamma irradiation on polymerization of pyrrole and glucose oxidase immobilization onto poly (pyrrole)/poly (vinyl alcohol) matrix

    Energy Technology Data Exchange (ETDEWEB)

    Idris, Sarada, E-mail: sarada@nuclearmalaysia.gov.my [Department of Radiation Technology, Malaysian Nuclear Agency, 43000, Bangi, Selangor (Malaysia); Department of Electrical, Electronic and Systems Engineering, Faculty of Engineering & Built Environment, Universiti Kebangsaan Malaysia, Bangi, 43600 (Malaysia); Bakar, Ahmad Ashrif A., E-mail: ashrif@ukm.edu.my [Department of Electrical, Electronic and Systems Engineering, Faculty of Engineering & Built Environment, Universiti Kebangsaan Malaysia, Bangi, 43600 (Malaysia); Thevy Ratnam, Chantara [Department of Radiation Technology, Malaysian Nuclear Agency, 43000, Bangi, Selangor (Malaysia); Kamaruddin, Nur Hasiba [Department of Electrical, Electronic and Systems Engineering, Faculty of Engineering & Built Environment, Universiti Kebangsaan Malaysia, Bangi, 43600 (Malaysia); Shaari, Sahbudin [Institute of Microengineering and Nanoelectronics, Universiti Kebangsaan Malaysia, Bangi, 43600 (Malaysia)

    2017-04-01

    Graphical abstract: The illustration of pyrrole polymerization, PVA crosslinking and immobilization of GOx onto polymer matrix. - Highlights: • Immobilization of glucose oxidase onto polymer matrices by gamma irradiation is proposed. • Crosslinking and grafting of polymers implies the immobilization reaction. • The mechanisms relies on gamma irradiation doses. • A simple single step process of polymerization, cross linking and immobilization by mean of gamma irradiation as was shown in Graphical abstract. - Abstract: This paper describes the immobilization of glucose oxidase, GOx onto polymer matrix comprising of poly(pyrrole), PPy and poly(vinyl alcohol), PVA using gamma irradiation technique. Py/PVA-GOx film was prepared by spreading PVA:GOx, 1:1 solution onto dried pyrrole film and exposed to gamma irradiation from cobalt 60 source at doses ranging from 0 to 60 kGy. The films were subjected to structural and morphological analyses by using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Scanning electron microscope (SEM), Field emission scanning electron microscope (FESEM) and Atomic-force microscopy (AFM) techniques. Similar studies were also made on pristine pyrrole film which served as control. The SEM and FTIR spectra of Py/PVA-GOx film revealed that pyrrole has been successfully polymerized through irradiation-induced reactions. The results on the morphological properties of the samples characterize using FESEM, SEM and AFM further confirmed the occurrence of radiation-induced modification of Py/PVA-GOx film. The FTIR spectra showed the existence of intermolecular interaction between polymer matrix and GOx indicating that GOx had been successfully immobilized onto Ppy/PVA matrix by radiation-induced reactions. Results revealed that radiation induced reactions such as polymerization of pyrrole, crosslinking of PVA, grafting between the adjacent PVA and pyrrole molecules as well as immobilization of GOx onto Ppy

  9. Influence of gamma irradiation on polymerization of pyrrole and glucose oxidase immobilization onto poly (pyrrole)/poly (vinyl alcohol) matrix

    International Nuclear Information System (INIS)

    Idris, Sarada; Bakar, Ahmad Ashrif A.; Thevy Ratnam, Chantara; Kamaruddin, Nur Hasiba; Shaari, Sahbudin

    2017-01-01

    Graphical abstract: The illustration of pyrrole polymerization, PVA crosslinking and immobilization of GOx onto polymer matrix. - Highlights: • Immobilization of glucose oxidase onto polymer matrices by gamma irradiation is proposed. • Crosslinking and grafting of polymers implies the immobilization reaction. • The mechanisms relies on gamma irradiation doses. • A simple single step process of polymerization, cross linking and immobilization by mean of gamma irradiation as was shown in Graphical abstract. - Abstract: This paper describes the immobilization of glucose oxidase, GOx onto polymer matrix comprising of poly(pyrrole), PPy and poly(vinyl alcohol), PVA using gamma irradiation technique. Py/PVA-GOx film was prepared by spreading PVA:GOx, 1:1 solution onto dried pyrrole film and exposed to gamma irradiation from cobalt 60 source at doses ranging from 0 to 60 kGy. The films were subjected to structural and morphological analyses by using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Scanning electron microscope (SEM), Field emission scanning electron microscope (FESEM) and Atomic-force microscopy (AFM) techniques. Similar studies were also made on pristine pyrrole film which served as control. The SEM and FTIR spectra of Py/PVA-GOx film revealed that pyrrole has been successfully polymerized through irradiation-induced reactions. The results on the morphological properties of the samples characterize using FESEM, SEM and AFM further confirmed the occurrence of radiation-induced modification of Py/PVA-GOx film. The FTIR spectra showed the existence of intermolecular interaction between polymer matrix and GOx indicating that GOx had been successfully immobilized onto Ppy/PVA matrix by radiation-induced reactions. Results revealed that radiation induced reactions such as polymerization of pyrrole, crosslinking of PVA, grafting between the adjacent PVA and pyrrole molecules as well as immobilization of GOx onto Ppy

  10. Physiological and biochemical changes in. gamma. -irradiated rice

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, M; Hasegawa, H; Hori, S [Osaka Prefecture (Japan). Radiation Center

    1975-12-01

    Metabolic disturbances resulting in growth retardation and death of rice irradiated with /sup 60/Co ..gamma..-rays at 10 to 40 kR dose levels were investigated. Seedling growth, release of storage products (reducing sugar and free amino acids) and incorporation of radioisotopic substances ((/sup 3/H)-uridine, (/sup 3/H)-thymidine and (/sup 3/H)-leucine) remained almost uninhibited at doses up to 20 kR but were much reduced at 40 kR. Following the 40 kR treatment, shoot elongation was terminated at the 5th day of germination, corresponding to an interruption in the release of reducing sugar. Furthermore, the onset of active increase in (/sup 3/H)-thymidine incorporation after germination was also delayed in the 40 kR irradiated samples. When the seeds had been cultured in glucose-medium immediately after irradiation there were significantly regular increases of survival and a disappearance in the delay in (/sup 3/H)-thymidine incorporation. However, glucose had no marked effect on subsequent growth and overall metabolic damage even though incorporation of (/sup 14/C)-glucose was slightly higher in the irradiated than in the control in the early stage of germination. It is suggested that the recovery from radiation damage in the early stages of germination can be enhanced by thw provision of glucose while recovery from damage leading to reduction of subsequent growth is less sensitive to glucose.

  11. Assessment of ambient gamma dose rate around a prospective uranium mining area of South India - A comparative study of dose by direct methods and soil radioactivity measurements

    Science.gov (United States)

    Karunakara, N.; Yashodhara, I.; Sudeep Kumara, K.; Tripathi, R. M.; Menon, S. N.; Kadam, S.; Chougaonkar, M. P.

    Indoor and outdoor gamma dose rates were evaluated around a prospective uranium mining region - Gogi, South India through (i) direct measurements using a GM based gamma dose survey meter, (ii) integrated measurement days using CaSO4:Dy based thermo luminescent dosimeters (TLDs), and (iii) analyses of 273 soil samples for 226Ra, 232Th, and 40K activity concentration using HPGe gamma spectrometry. The geometric mean values of indoor and outdoor gamma dose rates were 104 nGy h-1 and 97 nGy h-1, respectively with an indoor to outdoor dose ratio of 1.09. The gamma dose rates and activity concentrations of 226Ra, 232Th, and 40K varied significantly within a small area due to the highly localized mineralization of the elements. Correlation study showed that the dose estimated from the soil radioactivity is better correlated with that measured directly using the portable survey meter, when compared to that obtained from TLDs. This study showed that in a region having localized mineralization in situ measurements using dose survey meter provide better representative values of gamma dose rates.

  12. 40 CFR 205.54-1 - Low speed sound emission test procedures.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Low speed sound emission test procedures. 205.54-1 Section 205.54-1 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) NOISE ABATEMENT PROGRAMS TRANSPORTATION EQUIPMENT NOISE EMISSION CONTROLS Medium and Heavy Trucks § 205...

  13. Anisotropic emission of the X-ray K-emission band of nitrogen in hexagonal boron nitride

    International Nuclear Information System (INIS)

    Tegeler, E.; Kosuch, N.; Wiech, G.; Faessler, A.

    1977-05-01

    The intensity distribution of the N K-emission band of hexagonal boron nitride samples with partially orientated crystallites was found to be strongly dependent upon the take-off angle of the emitted radiation. The observed emission bands can be separated unambiguously into a sigma- and a π-subband. On the basis of the directional characteristic of radiating dipoles within the layers (sigma-bondings) and perpendicular to the layers (π-bonding) the angular dependence of the intensity of the subbands is quantitatively explained. In addition the degree of orientation of the crystallites on the sample can be determined. The intensity distributions of the emission bands to be expected for single crystals and for samples without any texture are determined; in the latter case the results are found to be in good agreement with experimental results. (orig.) [de

  14. Potential Application of Gamma Irradiated Polyvinyl Pyrrolidone (PVP) - Starch Hydrogel As Fever Cooling Plaster

    International Nuclear Information System (INIS)

    Darmawan Darwis; Lely Hardiningsih

    2010-01-01

    Research on the development of hydrogel for cooling fever by using gamma irradiation technique has been done. The hydrogel was prepared by irradiating the mixture of PVP with concentration of 7% (w/v) and starch with various concentrations using gamma ray at irradiation dose of 20 to 40 kGy. The results showed that optimum starch concentration to make solid constituent of PVP-starch prior to irradiation were 10-15%. Gel fraction of PVP-starch hydrogel showed an increase by increasing of irradiation dose up to 35 kGy, and acceleration of irradiation dose did not have any effect on gel fraction. At the same irradiation dose, there was no influence of starch concentration on gel fraction. Maximum gel fraction was achieved at 35 kGy irradiation dose. Water content of PVP-Starch hydrogel with starch concentration of 10 to 15% was in the range of 73 - 76%. Water content of hydrogel depends on starch concentration, while irradiation dose does not give any effect on water content of hydrogel. Hydrogel with high water content is potential to be used for fever cooling. Hydrogel PVP-Starch with starch concentration of 10% irradiated by gamma irradiation at the dose of 35 kGy had the ability to reduce water temperature from 40°C to 36°C in 21 minutes, while it took 24 minutes for the hydrogel with starch concentration of 12.5 and 15%. Commercial cooling pad hydrogel need 24 minutes to reduce temperature of water from 40°C to 36°C. Based on these results, it can be concluded that PVP hydrogel with 10% starch content showed faster cooling effect compared to hydrogel with 12.5 and 15 % starch content as well as the commercial hydrogel. Beside these advantages, the hydrogel obtained has some disadvantages such as low stickiness, brittle and opaque. (author)

  15. Spectrum analysis with indoor multi-channels gamma-rays spectrometer (NaI(Tl))

    International Nuclear Information System (INIS)

    Hou Shengli; Fan Weihua

    2005-01-01

    Two calculational methods for analyzing the spectrum which measured by indoor low background multi-channels gamma-rays spectrometer (Na(Tl)) to get the specific activity of 226 Ra, 232 Th and 40 K of the sample are discussed, they are the spectrum analysis method and the characteristic energy peak method (inverse matrix method) respectively. The sample spectrum are analyzed with the program designed according to the two methods, and compared with the results by HPGe gamma-rays spectrometer, showing that the relative deviation is ≤10% with the two methods. (authors)

  16. Quantification of uncertainty in gamma spectrometric analysis of food and environmental samples

    International Nuclear Information System (INIS)

    Yii Mei Wo; Zaharudin Ahmad; Norfaizal Mohamed

    2005-01-01

    Gamma Spectrometry is widely used to determine the activity of gamma-ray emitter radionuclide inside a sample. Reporting the activity of the measurement for a sample should not be a single value only but it shall be associated with a reasonable uncertainty value since disintegration of radionuclide is a random/spontaneous process. This paper will focus on how the uncertainty was estimated, quantified and calculated, when measuring the activity of Cs-134 and Cs-137 in food and Ra-226, Ra-228 and K-40 in the environmental samples. (Author)

  17. Emission computerized axial tomography from multiple gamma-camera views using frequency filtering.

    Science.gov (United States)

    Pelletier, J L; Milan, C; Touzery, C; Coitoux, P; Gailliard, P; Budinger, T F

    1980-01-01

    Emission computerized axial tomography is achievable in any nuclear medicine department from multiple gamma camera views. Data are collected by rotating the patient in front of the camera. A simple fast algorithm is implemented, known as the convolution technique: first the projection data are Fourier transformed and then an original filter designed for optimizing resolution and noise suppression is applied; finally the inverse transform of the latter operation is back-projected. This program, which can also take into account the attenuation for single photon events, was executed with good results on phantoms and patients. We think that it can be easily implemented for specific diagnostic problems.

  18. Gamma-Knife: operation ohne Skalpell

    OpenAIRE

    АБЛЯЕВА В.И.; НИКОЛАЕВА Н.А.; ДЕНИСОВА О.С.

    2015-01-01

    Das Gamma-Knife ist ein Operationsroboter, mit dem Ärzte durch Photonenstrahlen im Körper operieren können. Die Photonen beschädigen die DNA von Zellen, so dass diese sich nicht mehr teilen können. Gutartige Tumoren vernarben in den Wochen und Monaten nach der Behandlung, bösartige zerfallen. Mit dem Gamma-Knife können unterschiedliche Arten von Tumoren behandelt werden, gutartige ebenso wie bösartige. Zu den Diagnosen, bei denen das Gamma-Knife in Frage kommt, gehören zum Beispiel Akustikusn...

  19. Interstellar medium structure and content and gamma ray astronomy

    International Nuclear Information System (INIS)

    Lebrun, F.

    1982-05-01

    A general description of gamma-ray astronomy is presented with special emphasis on the study of diffuse gamma-ray emission. This is followed by a collection of reflections and observations on the structure and the gas and dust content of the local interstellar medium. Results of gamma-ray observations on the local interstellar medium are given. The last part is devoted to the whole of the galactic gamma-ray emission and its interpretation [fr

  20. Activity concentrations and mean annual effective dose from gamma-emitting radionuclides in the Lebanese diet

    International Nuclear Information System (INIS)

    Nasreddine, L.; Hwalla, N.; El Samad, O.; Baydoun, R.; Hamze, M.; Parent-Massin, D.

    2008-01-01

    Since the primary factor contributing to the internal effective dose in the human organism is contaminated food, the control of radionuclides in food represents the most important means of protection. This study was conducted to determine the levels of the dietary exposure of the Lebanese population to gamma-emitting radioisotopes. The activity concentrations of gamma-emitting radioisotopes have been measured in food samples that represent the market basket of an adult urban population in Lebanon. The artificial radionuclide 137 Cs was measured above detection limits in only fish, meat and milk-based deserts. The most abundant natural radionuclide was 40 K (31-121 Bq kg -1 ), with the highest content in fish and meat samples. The annual mean effective dose contributed by 40 K in the reference typical diet was estimated equal to 186 μSv y -1 , a value reasonably consistent with findings reported by several other countries. (authors)

  1. Mapping of radiation anomalies using UAV mini-airborne gamma-ray spectrometry.

    Science.gov (United States)

    Šálek, Ondřej; Matolín, Milan; Gryc, Lubomír

    2018-02-01

    Localization of size-limited gamma-ray anomalies plays a fundamental role in uranium prospecting and environmental studies. Possibilities of a newly developed mini-airborne gamma-ray spectrometric equipment were tested on a uranium anomaly near the village of Třebsko, Czech Republic. The measurement equipment was based on a scintillation gamma-ray spectrometer specially developed for unmanned aerial vehicles (UAV) mounted on powerful hexacopter. The gamma-ray spectrometer has two 103 cm 3 BGO scintillation detectors of relatively high sensitivity. The tested anomaly, which is 80 m by 40 m in size, was investigated by ground gamma-ray spectrometric measurement in a detail rectangular measurement grid. Average uranium concentration is 25 mg/kg eU attaining 700 mg/kg eU locally. The mini-airborne measurement across the anomaly was carried out on three 100 m long parallel profiles at eight flight altitudes from 5 to 40 m above the ground. The resulting 1 s 1024 channel gamma-ray spectra, recorded in counts per second (cps), were processed to concentration units of K, U and Th, while total count (TC) was reported in cps. Increased gamma ray intensity of the anomaly was indicated by mini-airborne measurement at all profiles and altitudes, including the highest altitude of 40 m, at which the recorded intensity is close to the natural radiation background. The reported instrument is able to record data with comparable quality as standard airborne survey, due to relative sensitive detector, lower flight altitude and relatively low flight speed of 1 m/s. The presented experiment brings new experience with using unmanned semi-autonomous aerial vehicles and the latest mini-airborne radiometric instrument. The experiment has demonstrated the instrument's ability to localize size-limited uranium anomalies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Application of the Monte Carlo method for the efficiency calibration of CsI and NaI detectors for gamma-ray measurements from terrestrial samples

    Energy Technology Data Exchange (ETDEWEB)

    Baccouche, S., E-mail: souad.baccouche@cnstn.rnrt.tn [UR-MDTN, National Center for Nuclear Sciences and Technology, Technopole Sidi Thabet, 2020 Sidi Thabet (Tunisia); Al-Azmi, D., E-mail: ds.alazmi@paaet.edu.kw [Department of Applied Sciences, College of Technological Studies, Public Authority for Applied Education and Training, Shuwaikh, P.O. Box 42325, Code 70654 (Kuwait); Karunakara, N., E-mail: karunakara_n@yahoo.com [University Science Instrumentation Centre, Mangalore University, Mangalagangotri 574199 (India); Trabelsi, A., E-mail: adel.trabelsi@fst.rnu.tn [UR-MDTN, National Center for Nuclear Sciences and Technology, Technopole Sidi Thabet, 2020 Sidi Thabet (Tunisia); UR-UPNHE, Faculty of Sciences of Tunis, El-Manar University, 2092 Tunis (Tunisia)

    2012-01-15

    Gamma-ray measurements in terrestrial/environmental samples require the use of high efficient detectors because of the low level of the radionuclide activity concentrations in the samples; thus scintillators are suitable for this purpose. Two scintillation detectors were studied in this work; CsI(Tl) and NaI(Tl) with identical size for measurement of terrestrial samples for performance study. This work describes a Monte Carlo method for making the full-energy efficiency calibration curves for both detectors using gamma-ray energies associated with the decay of naturally occurring radionuclides {sup 137}Cs (661 keV), {sup 40}K (1460 keV), {sup 238}U ({sup 214}Bi, 1764 keV) and {sup 232}Th ({sup 208}Tl, 2614 keV), which are found in terrestrial samples. The magnitude of the coincidence summing effect occurring for the 2614 keV emission of {sup 208}Tl is assessed by simulation. The method provides an efficient tool to make the full-energy efficiency calibration curve for scintillation detectors for any samples geometry and volume in order to determine accurate activity concentrations in terrestrial samples. - Highlights: Black-Right-Pointing-Pointer CsI (Tl) and NaI (Tl) detectors were studied for the measurement of terrestrial samples. Black-Right-Pointing-Pointer Monte Carlo method was used for efficiency calibration using natural gamma emitting terrestrial radionuclides. Black-Right-Pointing-Pointer The coincidence summing effect occurring for the 2614 keV emission of {sup 208}Tl is assessed by simulation.

  3. Studies of natural radioactivity in cement products using gamma ray spectroscopy

    International Nuclear Information System (INIS)

    Ibrahim, N.; Periasamy, V.

    2000-01-01

    Evidence from our earlier study on several types of building materials has shown that cement contains a substantial amount of natural occurring radioactive materials. There are many brands of cement products available in Malaysia. Although the basic ingredients of cement are similar across brand, their proportion varies. In this study we have selected twelve brands of cement products which are analysed for natural radioactivity (U,Th,K) using gamma ray spectrometry. The gamma energies of interest are 583.1 keV, 609.3 keV and 1460 keV for nuclides 208 Tl, 214 Bi and 40 K respectively. Our findings show a relatively high activity of 40 K for all cement brands, ranging from 33 Bq/kg to as high as 3010 Bq/kg. Uranium activity ranges from 9Bq/kg to 672 Bq/kg while thorium activity was found range from 6Bq/kg to 94 Bq/kg. The radium equivalent activity is calculated for all brands and the values obtained range between 24 Bq/kg to 879 Bq/kg. Eight out of twelve products possess radium equivalent greater than 370 Bq/kg, a threshold limit for radiation dose equivalent to 1.5 mSv per annum. (author)

  4. THE ROLE OF FAST MAGNETIC RECONNECTION ON THE RADIO AND GAMMA-RAY EMISSION FROM THE NUCLEAR REGIONS OF MICROQUASARS AND LOW LUMINOSITY AGNs

    International Nuclear Information System (INIS)

    Kadowaki, L. H. S.; Pino, E. M. de Gouveia Dal; Singh, C. B.

    2015-01-01

    Fast magnetic reconnection events can be a very powerful mechanism operating in the core region of microquasars and active galactic nuclei (AGNs). In earlier work, it has been suggested that the power released by fast reconnection events between the magnetic field lines lifting from the inner accretion disk region and the lines anchored into the central black hole could accelerate relativistic particles and produce the observed radio emission from microquasars and low luminosity AGNs (LLAGNs). Moreover, it has been proposed that the observed correlation between the radio emission and the mass of these sources, spanning 10 10 orders of magnitude in mass, might be related to this process. In the present work, we revisit this model comparing two different fast magnetic reconnection mechanisms, namely, fast reconnection driven by anomalous resistivity (AR) and by turbulence. We apply the scenario above to a much larger sample of sources (including also blazars, and gamma-ray bursts—GRBs), and find that LLAGNs and microquasars do confirm the trend above. Furthermore, when driven by turbulence, not only their radio but also their gamma-ray emission can be due to magnetic power released by fast reconnection, which may accelerate particles to relativistic velocities in the core region of these sources. Thus the turbulent-driven fast reconnection model is able to reproduce verywell the observed emission. On the other hand, the emission from blazars and GRBs does not follow the same trend as that of the LLAGNs and microquasars, indicating that the radio and gamma-ray emission in these cases is produced beyond the core, along the jet, by another population of relativistic particles, as expected

  5. Gamma radiation induced changes in nuclear waste glass containing Eu

    Science.gov (United States)

    Mohapatra, M.; Kadam, R. M.; Mishra, R. K.; Kaushik, C. P.; Tomar, B. S.; Godbole, S. V.

    2011-10-01

    Gamma radiation induced changes were investigated in sodium-barium borosilicate glasses containing Eu. The glass composition was similar to that of nuclear waste glasses used for vitrifying Trombay research reactor nuclear waste at Bhabha Atomic Research Centre, India. Photoluminescence (PL) and electron paramagnetic resonance (EPR) techniques were used to study the speciation of the rare earth (RE) ion in the matrix before and after gamma irradiation. Judd-Ofelt ( J- O) analyses of the emission spectra were done before and after irradiation. The spin counting technique was employed to quantify the number of defect centres formed in the glass at the highest gamma dose studied. PL data suggested the stabilisation of the trivalent RE ion in the borosilicate glass matrix both before and after irradiation. It was also observed that, the RE ion distributes itself in two different environments in the irradiated glass. From the EPR data it was observed that, boron oxygen hole centre based radicals are the predominant defect centres produced in the glass after irradiation along with small amount of E’ centres. From the spin counting studies the concentration of defect centres in the glass was calculated to be 350 ppm at 900 kGy. This indicated the fact that bulk of the glass remained unaffected after gamma irradiation up to 900 kGy.

  6. Multiwavelength Study of Gamma-Ray Bright Blazars

    Science.gov (United States)

    Morozova, Daria; Larionov, V. M.; Hagen-Thorn, V. A.; Jorstad, S. G.; Marscher, A. P.; Troitskii, I. S.

    2011-01-01

    We investigate total intensity radio images of 6 gamma-ray bright blazars (BL Lac, 3C 279, 3C 273, W Com, PKS 1510-089, and 3C 66A) and their optical and gamma-ray light curves to study connections between gamma-ray and optical brightness variations and changes in the parsec-scale radio structure. We use high-resolution maps obtained by the BU group at 43 GHz with the VLBA, optical light curves constructed by the St.Petersburg State U. (Russia) team using measurements with the 0.4 m telescope of St.Petersburg State U. (LX200) and the 0.7 m telescope of the Crimean Astrophysical Observatory (AZT-8), and gamma-ray light curves, which we have constructed with data provided by the Fermi Large Area Telescope. Over the period from August 2008 to November 2009, superluminal motion is found in all 6 objects with apparent speed ranging from 2c to 40c. The blazars with faster apparent speeds, 3C 273, 3C 279, PKS 1510-089, and 3C 66A, exhibit stronger variability of the gamma-ray emission. There is a tendency for sources with sharply peaked gamma-ray flares to have faster jet speed than sources with gamma-ray light curves with no sharp peaks. Gamma-ray light curves with sharply peaked gamma-ray flares possess a stronger gamma-ray/optical correlations. The research at St.Petersburg State U. was funded by the Minister of Education and Science of the Russian Federation (state contract N#P123). The research at BU was funded in part by NASA Fermi Guest Investigator grant NNX08AV65G and by NSF grant AST-0907893. The VLBA is an instrument of the National Radio Astronomy Observatory, a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

  7. ORIGIN OF THE GALACTIC DIFFUSE X-RAY EMISSION: IRON K-SHELL LINE DIAGNOSTICS

    Energy Technology Data Exchange (ETDEWEB)

    Nobukawa, Masayoshi [Department of Teacher Training and School Education, Nara University of Education, Takabatake-cho, Nara, 630-8528 (Japan); Uchiyama, Hideki [Faculty of Education, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529 (Japan); Nobukawa, Kumiko K.; Koyama, Katsuji [Department of Physics, Graduate School of Science, Kyoto University, Kitashirakawa-oiwake-cho, Sakyo-ku, Kyoto, 606-8502 (Japan); Yamauchi, Shigeo, E-mail: nobukawa@nara-edu.ac.jp [Department of Physics, Nara Women’s University, Kitauoyanishimachi, Nara, 630-8506 (Japan)

    2016-12-20

    This paper reports detailed K-shell line profiles of iron (Fe) and nickel (Ni) of the Galactic Center X-ray Emission (GCXE), Galactic Bulge X-ray Emission (GBXE), Galactic Ridge X-ray Emission (GRXE), magnetic Cataclysmic Variables (mCVs), non-magnetic Cataclysmic Variables (non-mCVs), and coronally Active Binaries (ABs). For the study of the origin of the GCXE, GBXE, and GRXE, the spectral analysis is focused on equivalent widths of the Fe i-K α , Fe xxv-He α , and Fe xxvi-Ly α  lines. The global spectrum of the GBXE is reproduced by a combination of the mCVs, non-mCVs, and ABs spectra. On the other hand, the GRXE spectrum shows significant data excesses at the Fe i-K α and Fe xxv-He α  line energies. This means that additional components other than mCVs, non-mCVs, and ABs are required, which have symbiotic phenomena of cold gas and very high-temperature plasma. The GCXE spectrum shows larger excesses than those found in the GRXE spectrum at all the K-shell lines of iron and nickel. Among them the largest ones are the Fe i-K α , Fe xxv-He α , Fe xxvi-Ly α , and Fe xxvi-Ly β  lines. Together with the fact that the scale heights of the Fe i-K α , Fe xxv-He α , and Fe xxvi-Ly α lines are similar to that of the central molecular zone (CMZ), the excess components would be related to high-energy activity in the extreme envelopment of the CMZ.

  8. Alterations in premating behavior and pheromone biology of gamma-irradiated Trichoplusia ni (Lepidoptera:Noctuidae)

    International Nuclear Information System (INIS)

    Szentesi, A.; McLaughlin, J.R.; Coffelt, J.A.

    1977-01-01

    Exposure of female cabbage looper pupae, Trichoplusia ni, to gamma irradiation at 0 to 72 hr before eclosion resulted in significantly reduced moving and calling activity of the adults. The effects were dose-related from 10 to 40 kR. Generally, irradiation in a nitrogen atmosphere slightly reduced deleterious effects, but fractionation of the radiation dose did not. Four-day-old irradiated females contained significantly more sex pheromone than untreated females, indicating that loss of pheromone is positively correlated to the amount of calling activity. Males exposed to 20 kR or 40 kR in nitrogen were not affected in their flight response in an olfactometer to a level of synthetic pheromone ca. equal to that released by a calling female or to 0.1 x this level. The response of males exposed to 40 kR in air, however, was significantly decreased at the lower pheromone concentration

  9. Physiological response of lovage (levisticum officinale, koch) plant to gamma radiation and organic fertilizers

    International Nuclear Information System (INIS)

    Taha, A.T.A.

    2009-01-01

    The main objective of this work is to study physiological response of lovage plant to gamma radiation and organic fertilizers.Two field experiments were conduct under conditions of newly reclaimed soil (sandy loam soil) during two successive seasons (2003/2004 and 2004/2005) in experimental farm , NRC,AEA Inshas. lovage fruits were irradiated before sowing with gamma rays at 0,20,40,60 and 80 Gy. Before planting farm yard manure (FYM) at rates of 0,20,30 and 40 m 3 /fed. Was applied to soil in combination with gamma doses in the first experiment, in the second one, chicken manure at 0,10,15 and 20 m 3 /fed. was added to soil before planting in combination with the same used gamma doses in first experiment. Growth of lovage plants was considerably stimulated by irradiating fruits before sowing with low gamma doses, in particularly at 60 Gy, which greatly increased plant height, number of branches/plant, stem thickness and dry matter yield of shoots. Similar trend was also observed with leaf chlorophyll content which increased due to low gamma doses . Low gamma doses markedly encouraged nutrients uptake by lovage plants which increased levels and total contents of N, P, K, Fe,Zn and Mn in plant shoots. Fruits yield, volatile oil % and oil yield and fruits index value were increased by low gamma doses particularly at 60 Gy.

  10. Gamma-ray and X-ray emission from the Galactic centre: hints on the nuclear star cluster formation history

    Science.gov (United States)

    Arca-Sedda, Manuel; Kocsis, Bence; Brandt, Timothy D.

    2018-06-01

    The Milky Way centre exhibits an intense flux in the gamma and X-ray bands, whose origin is partly ascribed to the possible presence of a large population of millisecond pulsars (MSPs) and cataclysmic variables (CVs), respectively. However, the number of sources required to generate such an excess is much larger than what is expected from in situ star formation and evolution, opening a series of questions about the formation history of the Galactic nucleus. In this paper we make use of direct N-body simulations to investigate whether these sources could have been brought to the Galactic centre by a population of star clusters that underwent orbital decay and formed the Galactic nuclear star cluster (NSC). Our results suggest that the gamma ray emission is compatible with a population of MSPs that were mass segregated in their parent clusters, while the X-ray emission is consistent with a population of CVs born via dynamical interactions in dense star clusters. Combining observations with our modelling, we explore how the observed γ ray flux can be related to different NSC formation scenarios. Finally, we show that the high-energy emission coming from the galactic central regions can be used to detect black holes heavier than 105M⊙ in nearby dwarf galaxies.

  11. FERMI DISCOVERY OF GAMMA-RAY EMISSION FROM NGC 1275

    International Nuclear Information System (INIS)

    Abdo, A. A.; Ackermann, M.; Ajello, M.; Bechtol, K.; Blandford, R. D.; Bloom, E. D.; Borgland, A. W.; Asano, K.; Baldini, L.; Bellazzini, R.; Bregeon, J.; Brez, A.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Baughman, B. M.; Bonamente, E.; Brigida, M.; Bruel, P.; Burnett, T. H.

    2009-01-01

    We report the discovery of high-energy (E > 100 MeV) γ-ray emission from NGC 1275, a giant elliptical galaxy lying at the center of the Perseus cluster of galaxies, based on observations made with the Large Area Telescope (LAT) of the Fermi Gamma-ray Space Telescope. The positional center of the γ-ray source is only ∼3' away from the NGC 1275 nucleus, well within the 95% LAT error circle of ∼5'. The spatial distribution of γ-ray photons is consistent with a point source. The average flux and power-law photon index measured with the LAT from 2008 August 4 to 2008 December 5 are F γ = (2.10 ± 0.23) x 10 -7 ph (>100 MeV) cm -2 s -1 and Γ = 2.17 ± 0.05, respectively. The measurements are statistically consistent with constant flux during the four-month LAT observing period. Previous EGRET observations gave an upper limit of F γ -8 ph (>100 MeV) cm -2 s -1 to the γ-ray flux from NGC 1275. This indicates that the source is variable on timescales of years to decades, and therefore restricts the fraction of emission that can be produced in extended regions of the galaxy cluster. Contemporaneous and historical radio observations are also reported. The broadband spectrum of NGC 1275 is modeled with a simple one-zone synchrotron/synchrotron self-Compton model and a model with a decelerating jet flow.

  12. Fermi Discovery of Gamma-Ray Emission from NGC 1275

    International Nuclear Information System (INIS)

    Abdo, Aous A.; Ackermann, M.; Ajello, M.; Asano, K.; Baldini, L.; Ballet, J.; Barbiellini, Guido; Bastieri, Denis; Baughman, B.M.; Bechtol, K.; Bellazzini, R.; Blandford, R.D.; Bloom, Elliott D.; Bonamente, E.; Borgland, A.W.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; Burnett, Thompson H.; Caliandro, G.A.

    2009-01-01

    We report the discovery of high-energy (E > 100 MeV) γ-ray emission from NGC 1275, a giant elliptical galaxy lying at the center of the Perseus cluster of galaxies, based on observations made with the Large Area Telescope (LAT) of the Fermi Gamma-ray Space Telescope. The positional center of the γ-ray source is only ∼3(prime) away from the NGC 1275 nucleus, well within the 95% LAT error circle of ∼5(prime). The spatial distribution of γ-ray photons is consistent with a point source. The average flux and power-law photon index measured with the LAT from 2008 August 4 to 2008 December 5 are F γ = (2.10 ± 0.23) x 10 -7 ph (>100 MeV) cm -2 s -1 and Γ = 2.17 ± 0.05, respectively. The measurements are statistically consistent with constant flux during the four-month LAT observing period. Previous EGRET observations gave an upper limit of F γ -8 ph (>100 MeV) cm -2 s -1 to the γ-ray flux from NGC 1275. This indicates that the source is variable on timescales of years to decades, and therefore restricts the fraction of emission that can be produced in extended regions of the galaxy cluster. Contemporaneous and historical radio observations are also reported. The broadband spectrum of NGC 1275 is modeled with a simple one-zone synchrotron/synchrotron self-Compton model and a model with a decelerating jet flow.

  13. SPATIALLY EXTENDED BRACKETT GAMMA EMISSION IN THE ENVIRONMENTS OF YOUNG STARS

    International Nuclear Information System (INIS)

    Beck, Tracy L.; Bary, Jeffery S.; McGregor, Peter J.

    2010-01-01

    The majority of atomic hydrogen Brγ emission detected in the spectra of young stellar objects is believed to arise from the recombination regions associated with the magnetospheric accretion of circumstellar disk material onto the forming star. In this paper, we present the results of a K-band integral field unit spectroscopic study of Brγ emission in eight young protostars: CW Tau, DG Tau, Haro 6-10, HL Tau, HV Tau C, RW Aur, T Tau, and XZ Tau. We spatially resolve Brγ emission structures in half of these young stars and find that most of the extended emission is consistent with the location and velocities of the known Herbig-Haro flows associated with these systems. At some velocities through the Brγ line profile, the spatially extended emission comprises 20% or more of the integrated flux in that spectral channel. However, the total spatially extended Brγ is typically less than ∼10% of the flux integrated over the full emission profile. For DG Tau and Haro 6-10 S, we estimate the mass outflow rate using simple assumptions about the hydrogen emission region and compare this to the derived mass accretion rate. We detect extended Brγ in the vicinity of the more obscured targets in our sample and conclude that spatially extended Brγ emission may exist toward other stars, but unattenuated photospheric flux probably limits its detectability.

  14. Fermi-LAT upper limits on gamma-ray emission from colliding wind binaries

    International Nuclear Information System (INIS)

    Werner, Michael; Reimer, O.; Reimer, A.

    2013-01-01

    Here, colliding wind binaries (CWBs) are thought to give rise to a plethora of physical processes including acceleration and interaction of relativistic particles. Observation of synchrotron radiation in the radio band confirms there is a relativistic electron population in CWBs. Accordingly, CWBs have been suspected sources of high-energy γ-ray emission since the COS-B era. Theoretical models exist that characterize the underlying physical processes leading to particle acceleration and quantitatively predict the non-thermal energy emission observable at Earth. Furthermore, we strive to find evidence of γ-ray emission from a sample of seven CWB systems: WR 11, WR 70, WR 125, WR 137, WR 140, WR 146, and WR 147. Theoretical modelling identified these systems as the most favourable candidates for emitting γ-rays. We make a comparison with existing γ-ray flux predictions and investigate possible constraints. We used 24 months of data from the Large Area Telescope (LAT) on-board the Fermi Gamma Ray Space Telescope to perform a dedicated likelihood analysis of CWBs in the LAT energy range. As a result, we find no evidence of γ-ray emission from any of the studied CWB systems and determine corresponding flux upper limits. For some CWBs the interplay of orbital and stellar parameters renders the Fermi-LAT data not sensitive enough to constrain the parameter space of the emission models. In the cases of WR140 and WR147, the Fermi-LAT upper limits appear to rule out some model predictions entirely and constrain theoretical models over a significant parameter space. A comparison of our findings to the CWB η Car is made.

  15. Data-driven Simulations of Magnetic Connectivity in Behind-the-Limb Gamma-ray Flares and Associated Coronal Mass Ejections

    Science.gov (United States)

    Jin, M.; Petrosian, V.; Liu, W.; Nitta, N.; Omodei, N.; Rubio da Costa, F.; Effenberger, F.; Li, G.; Pesce-Rollins, M.

    2017-12-01

    Recent Fermi detection of high-energy gamma-ray emission from the behind-the-limb (BTL) solar flares pose a puzzle on the particle acceleration and transport mechanisms in such events. Due to the large separation between the flare site and the location of gamma-ray emission, it is believed that the associated coronal mass ejections (CMEs) play an important role in accelerating and subsequently transporting particles back to the Sun to produce obseved gamma-rays. We explore this scenario by simulating the CME associated with a well-observed flare on 2014 September 1 about 40 degrees behind the east solar limb and by comparing the simulation and observational results. We utilize a data-driven global magnetohydrodynamics model (AWSoM: Alfven-wave Solar Model) to track the dynamical evolution of the global magnetic field during the event and investigate the magnetic connectivity between the CME/CME-driven shock and the Fermi emission region. Moreover, we derive the time-varying shock parameters (e.g., compression ratio, Alfven Mach number, and ThetaBN) over the area that is magnetically connected to the visible solar disk where Fermi gamma-ray emission originates. Our simulation shows that the visible solar disk develops connections both to the flare site and to the CME-driven shock during the eruption, which indicate that the CME's interaction with the global solar corona is critical for understanding such Fermi BTL events and gamma-ray flares in general. We discuss the causes and implications of Fermi BTL events, in the framework of a potential shift of paradigm on particle acceleration in solar flares/CMEs.

  16. 40 CFR 63.2500 - How do I comply with emissions averaging?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 12 2010-07-01 2010-07-01 true How do I comply with emissions averaging? 63.2500 Section 63.2500 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Alternative Means of Compliance § 63.2500 How do I comply with emissions averaging? (a) For an existing source...

  17. 40 CFR 1060.102 - What permeation emission control requirements apply for fuel lines?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false What permeation emission control... AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EVAPORATIVE EMISSIONS FROM NEW AND IN-USE NONROAD AND STATIONARY EQUIPMENT Emission Standards and Related Requirements § 1060.102 What permeation...

  18. 40 CFR 1060.103 - What permeation emission control requirements apply for fuel tanks?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false What permeation emission control... AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EVAPORATIVE EMISSIONS FROM NEW AND IN-USE NONROAD AND STATIONARY EQUIPMENT Emission Standards and Related Requirements § 1060.103 What permeation...

  19. Determination of uranium and thorium using gamma spectrometry: A pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Olivares, D.M.M.; Koch, E.S.; Manso Guevara, M.V.; Garcia Velasco, F., E-mail: diango.mo87@gmail.com [Universidade Estadual de Santa Cruz (UNESC), Ilhéus, BA (Brazil)

    2017-07-01

    This paper presents the results of a pilot experiment aimed at standardizing procedures for the CPqCTR/UESC Gamma Spectrometry Laboratory (LEG) for the quantification of natural radioactive elements in solid environmental samples. The concentrations of {sup 238}U, {sup 232}Th and {sup 40}K in two sediment matrix belonging to the Caetité region were determined, by using the absolute method with uncertainties about 5%. The results were obtained using gamma spectrometry with a high-resolution p-type HPGe detector. As a closure, the absorbed dose, radium equivalent activity and the annual effective dose were calculated. (author)

  20. Gamma-Ray Lenses for Astrophysics-and the Gamma-Ray Imager Mission GRI

    DEFF Research Database (Denmark)

    Wunderer, C. B.; Ballmoos, P. V.; Barriere, N.

    2009-01-01

    Observations of the gamma-ray sky reveal the most powerful sources and the most violent events in the Universe. While at lower wavebands the observed emission is generally dominated by thermal processes, the gamma-ray sky provides us with a view on the non-thermal Universe. Here particles are acc...