Nucleon-nucleon optical model for energies to 3 GeV

International Nuclear Information System (INIS)

Funk, A.; Von Geramb, H.V.; University of Melbourne, VIC; Amos, K.A.

2001-01-01

Several nucleon-nucleon potentials, Paris, Nijmegen, Argonne, and those derived by quantum inversion, which describe the NN interaction for T Lab ≤ 300 MeV are extended in their range of application as NN optical models. Extensions are made in r-space using complex separable potentials definable with a wide range of form factor options including those of boundary condition models. We use the latest phase shift analyses SP00 (FA00, WI00) of Arndt et al. from 300 MeV to 3 GeV to determine these extensions. The imaginary parts of the optical model interactions account for loss of flux into direct or resonant production processes. The optical potential approach is of particular value as it permits one to visualize fusion, and subsequent fission, of nucleons when T Lab > 2 GeV. We do so by calculating the scattering wave functions to specify the energy and radial dependences of flux losses and of probability distributions. Furthermore, half-off the energy shell t-matrices are presented as they are readily deduced with this approach. Such t-matrices are required for studies of few- and many-body nuclear reactions

XRD study of yttria stabilized zirconia irradiated with 7.3 MeV Fe, 10 MeV I, 16 MeV Au, 200 MeV Xe and 2.2 GeV Au ions

Energy Technology Data Exchange (ETDEWEB)

Nakano, K.; Yoshizaki, H. [Department of Materials Science, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan); Saitoh, Y. [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, Takasaki, Gunma 370-1292 (Japan); Ishikawa, N. [Tokai Research and Development Center, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Iwase, A., E-mail: iwase@mtr.osakafu-u.ac.jp [Department of Materials Science, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan)

2016-03-01

To simulate energetic neutron irradiation effects, yttria-stabilized zirconia (YSZ) which is one of the major materials for electrical corrosion potential sensors (ECP sensors) was irradiated with heavy ions at energies ranging from 7.3 MeV to 2.2 GeV. Ion irradiation effects on the lattice structure were analyzed using the X-ray diffraction (XRD). The increase in lattice constant was induced by the ion irradiation. It was dominated by the elastic collision process and not by the electronic excitation process. The lattice disordering which was observed as a broadening of XRD peaks was also induced by the irradiation especially for 200 MeV Xe ion irradiation. The present result suggests that the expansion and/or the disordering of YSZ lattice induced by energetic neutrons may affect the durability of a joint interface between a metal housing and YSZ membrane for the usage of ECP sensors in nuclear power reactors.

The future machine with electrons of 15-30 GeV

International Nuclear Information System (INIS)

Tkatchenko, A.

1992-01-01

This article presents the project of european linear accelerator with a continuous beam of high energy electrons for the Nuclear Physics researches. Based on a superconducting linear accelerator crossed several times, this machine will be able to produce beams of 15 GeV in a first time, then 30 GeV, by increasing of accelerator cavity field without modifying the beam circulation system

Study of the p+{sup 12}C reaction at energies up to 30 MeV

Energy Technology Data Exchange (ETDEWEB)

Harada, Masahide; Yamamoto, A.; Yoshioka, S. [Kyushu Univ., Fukuoka (Japan)] [and others

1998-03-01

Double differential cross sections of charged-particles emitted in the p+{sup 12}C reaction were measured in the energy region from 14 to 26 MeV. The observed continuous components of emitted protons and {alpha}-particles were analyzed by assuming sequential decay of intermediate reaction products and/or simultaneous breakup process. It was found that the three body simultaneous decay, p+{alpha}+{sup 8}Be, and the sequential decay via p+{sup 12}C{sup *}{sub 3-} and {alpha}+{sup 9}B{sub g.s.} are most important in the proton-induced breakup of {sup 12}C for energies up to 30 MeV. (author)

γ astrophysics above 10-30 GeV with the MAGIC telescope

International Nuclear Information System (INIS)

Mirzoyan, Razmick

1999-01-01

The project on the 17 m oe telescope, dubbed MAGIC (Major Atmospheric Gamma Imaging Cherenkov Telescope), is dedicated for γ astrophysics in the energy range from 10-30 GeV till 50-100 TeV. MAGIC will for the first time allow to explore with very high sensitivity the energy range 10-300 GeV and to bridge the existing energy gap between satellite and ground-based air Cherenkov measurements. We believe MAGIC will serve as a prototype for future multi-telescope γ ray observatories

A 30 MeV H- cyclotron for isotope production

International Nuclear Information System (INIS)

Milton, B.F.; Dawson, R.; Erdman, K.L.

1989-05-01

Because of an expanding market for radioisotopes there is a need for a new generation of cyclotrons designed specifically for this purpose. TRIUMF is cooperating with a local industrial company in designing and constructing such a cyclotron. It will be a four sector H - cyclotron, exploiting the newly developed high brightness multicusp ion source. This source with H - current capability in excess of 5 mA makes feasible accelerated H - beam intensities of up to 500 μA. Beam extraction is by stripping to H + in a thin graphite foil. Extraction of two high-intensity beams, with energy variable from 15 to 30 MeV is planned. The use of an external ion source, provision of a good vacuum in the acceleration region, and the careful choice of materials for components in the median plane leads to a cyclotron that will have low activation and can be easily serviced in spite of the very high operating beam intensities. A design extension to 70 MeV using many of the design features of the 30 MeV cyclotron can be easily made. Such a machine with a good quality variable energy beam is a highly desirable source of protons for isotope production, injection into higher energy high intensity acceleration, injection into higher energy high intensity accelerators, and as an irradiation facility for ocular melanomas. Design of the 30 MeV cyclotron is well advanced and construction is in progress

Response of TAPS to monochromatic photons with energies between 45 and 790 MeV

International Nuclear Information System (INIS)

Gabler, A.R.; Doering, W.; Fuchs, M.; Krusche, B.; Metag, V.; Novotny, R.; Roebig-Landau, M.; Stroeher, H.; Tries, V.; Molenaar, C.; Loehner, H.; Van Pol, J.H.G.; Raschke, A.; Sumbera, M.; Venema, L.B.; Wilschut, H.W.; Averbeck, R.; Niebur, W.; Schubert, A.; Simon, R.S.; Beck, R.; Peise, J.; Miller, G.J.; Owens, R.O.; Anton, G.

1994-01-01

The Two Arm Photon Spectrometer TAPS - comprising 384 plastic-BaF 2 scintillator telescopes - was tested with monochromatic photons in the energy range between 45 and 790 MeV. The energy resolution for a collimated photon beam hitting the central detector module was determined to σ/E=0.59%xE -1/2 γ +1.9% (E γ given in GeV). For the the fast scintillation component alone σ/E=0.79%xE -1/2 γ +1.8% has been measured. The position resolution of the point of impact amounts to Δx=2 cm (FWHM) at the highest energies which corresponds to 30% of the diameter of an individual module. Monte Carlo simulations using the code GEANT3 are in good agreement with the experimental results. ((orig.))

Upgrading of sesame from 800 MeV to 2.5 GeV (Summary of the Technical Design)

International Nuclear Information System (INIS)

Asfour, F.I.

2004-01-01

A Synchrotron-light for Experimental Science and Applications in the Middle East (SESAME), was decided to be built in Jordan as a gift by Germany, based on BESSY 800 MeV synchrotron in Berlin after upgrading to serve as a seed for a new research center in 1998. The initial proposal for SESAME issued in 1999 to move BESSY to the Middle East in a modified form to high performance machine that would cover a broad spectral range, including hard X-rays. For chat BESSY-1, is changed to six-fold symmetry by changing the circumference from 64 to 100 meters and modification of bending magnets, thus the energy was increased to 1 GeV. To reach hard X-ray the intention was to introduce two 13 - pole superconducting wigglers with magnetic field 7.5 tesla, these wigglers provide a critical energy of 5 KeV and useful flux up to 20 KeV. However these wigglers have some disadvantages :1) they are costly, 2) need a special knowledge for running and 3) have an influence on beam behavior. In 2000 - 2001 appeared a scientific need of more beam lines in this spectral range (most users require hard X-ray). The simplest way of doing this is by getting hard X-ray from bending magnets. This is possible by increasing the energy to 2 GeV. Since Jordan will provide the building as a copy of the ANKA (60 m x 60 m) Synchrotron Light Source with 2.5 GeV storage ring. The design of SESAME project has been worked with maximum circumference 124 m. It is a 8- fold symmetry machine with energy 2 GeV. By using gradient bending magnets it is possible to have 12 for the installation of insertion devices and furthermore a reduction of natural emittance down to 18 nm rad. This is really the art of synchrotron light source. This was done in July 2002. To enhance the hard X-ray capability to be more in line, it was suggested to increase the energy up to 2.5 GeV. The option of 2.5 GeV machine is to explore its use with 2 in vacuum undulators, and of running the 2.5 machine at 2 GeV if that is needed for ultra

Total cross section measurements for νμ, ν-barμ interactions in 3 - 30 GeV energy range with IHEP - JINR neutrino detector

International Nuclear Information System (INIS)

Anikeev, V.B.; Belikov, S.V.; Borisov, A.A.

1995-01-01

The results of total cross section measurements for the ν μ , ν-bar μ interactions with isoscalar target in the 3 - 30 GeV energy range have been presented. The data were obtained with the IHEP - JINR Neutrino Detector in the 'natural' neutrino beams of the U - 70 accelerator. The significant deviation from the linear dependence for σ tot versus neutrino energy is determined in the energy range less than 15 GeV. 46 refs., 10 figs., 5 tabs

Measurement of the high-energy neutron flux on the surface of the natural uranium target assembly QUINTA irradiated by deuterons of 4- and 8-GeV energy

International Nuclear Information System (INIS)

Adam, J.; Baldin, A.A.; Chilap, V.

2014-01-01

Experiments with a natural uranium target assembly QUINTA exposed to 4- and 8 GeV deuteron beams of the Nuclotron accelerator at the Joint Institute for Nuclear Research (Dubna) are analyzed. The 129 I, 232 Th, 233 U, 235 U, nat U, 237 Np, 238 Pu, 239 Pu and 241 Am radioactive samples were installed on the surface of the QUINTA set-up and irradiated with secondary neutrons. The neutron flux through the RA samples was monitored by Al foils. The reaction rates of 27 Al(n, y 1 ) 24 Na, 27 Al(n, y 2 ) 22 Na and 27 Al(n, y 3 ) 7 Be reactions with the effective threshold energies of 5, 27 and 119 MeV were measured at both 4- and 8-GeV deuteron beam energies. The average neutron fluxes between the effective threshold energies and the effective ends of the neutron spectra (which are 800 or 1000 MeV for energy of 4- or 8-GeV deuterons) were determined. The evidence for the intensity shift of the neutron spectra to higher neutron energies with the increase of the deuteron energy from 4 to 8 GeV was found from the ratios of the average neutron fluxes. The reaction rates and the average neutron fluxes were calculated with MCNPX2.7 and MARS15 codes.

First measurement of the VESUVIO neutron spectrum in the 30-80 MeV energy range using a Proton Recoil Telescope technique

Science.gov (United States)

Cazzaniga, C.; Tardocchi, M.; Croci, G.; Frost, C.; Giacomelli, L.; Grosso, G.; Hjalmarsson, A.; Rebai, M.; Rhodes, N. J.; Schooneveld, E. M.; Gorini, G.

2013-11-01

Measurements of the fast neutron energy spectrum at the ISIS spallation source are reported. The measurements were performed with a Proton Recoil Telescope consisting of a thin plastic foil placed in the neutron beam and two scintillator detectors. Results in the neutron energy range 30 MeV < En < 80 MeV are in good agreement with Monte Carlo simulations of the neutron spectrum.

A study of energy-energy correlations in e+e- annihilations at √s = 34.6 GeV

International Nuclear Information System (INIS)

Berger, C.; Genzel, H.; Lackas, W.; Pielorz, J.; Raupach, F.; Wagner, W.; Ferrarotto, F.; Gaspero, M.; Stella, B.; Zachara, M.; Bussey, P.J.; Cartwright, S.L.; Dainton, J.B.; King, B.T.; Raine, C.; Scarr, J.M.; Skillicorn, I.O.; Smith, K.M.; Thomson, J.C.; Achterberg, O.; Blobel, V.; Burkart, D.; Diehlmann, K.; Feindt, M.; Kapitza, H.; Koppitz, B.; Krueger, M.; Poppe, M.; Spitzer, H.; Staa, R. van; Almeida, F.; Baecker, A.; Barreiro, F.; Brandt, S.; Derikum, K.; Grupen, C.; Meyer, H.J.; Mueller, H.; Neumann, B.; Rost, M.; Stupperich, K.; Zech, G.; Alexander, G.; Bella, G.; Gnat, Y.; Grunhaus, J.; Junge, H.; Kraski, K.; Maxeiner, C.; Maxeiner, H.; Meyer, H.; Schmidt, D.; Buerger, J.; Criegee, L.; Deuter, A.; Franke, G.; Gerke, C.; Knies, G.; Lewendel, B.; Meyer, J.; Michelsen, U.; Pape, K.H.; Timm, U.; Winter, G.G.; Zimmermann, W.

1985-05-01

We present high statistics measurements of the energy-energy correlation (EEC) and its related asymmetry (AEEC) in e + e - annihilation at a c.m. energy of 34.6 GeV. We find that the energy dependence as well as the large angle behaviour of the latter are well described by perturbative QCD calculations to O(αsub(s) 2 ). Non-pertubative effects are estimated with the help of fragmentation models in which different jet topologies are separated using (epsilon,delta) cuts, and found to be small. The extracted values of Δsub(MS) lie between 100 and 300 MeV. (orig.)

First measurement of the VESUVIO neutron spectrum in the 30–80 MeV energy range using a Proton Recoil Telescope technique

International Nuclear Information System (INIS)

Cazzaniga, C; Tardocchi, M; Croci, G; Grosso, G; Rebai, M; Gorini, G; Frost, C; Rhodes, N J; Schooneveld, E M; Giacomelli, L; Hjalmarsson, A

2013-01-01

Measurements of the fast neutron energy spectrum at the ISIS spallation source are reported. The measurements were performed with a Proton Recoil Telescope consisting of a thin plastic foil placed in the neutron beam and two scintillator detectors. Results in the neutron energy range 30 MeV n < 80 MeV are in good agreement with Monte Carlo simulations of the neutron spectrum

Physics with a high-intensity proton accelerator below 30 GeV

International Nuclear Information System (INIS)

Hoffman, C.M.

1982-01-01

The types of physics that would be pursued at a high-intensity, moderate-energy proton accelerator are discussed. The discussion is drawn from the deliberations of the 30-GeV subgroup of the Fixed-Target Group at this workshop

5-10 GeV neutrinos from gamma-Ray burst fireballs

Science.gov (United States)

Bahcall; Meszaros

2000-08-14

A gamma-ray burst fireball is likely to contain an admixture of neutrons. Inelastic collisions between differentially streaming protons and neutrons in the fireball produce nu(&mgr;) (nu;(&mgr;)) of approximately 10 GeV as well as nu(e) (nu;(e)) of approximately 5 GeV, which could produce approximately 7 events/year in km(3) detectors, if the neutron abundance is comparable to that of protons. Photons of approximately 10 GeV from pi(0) decay and approximately 100 MeV nu;(e) from neutron decay are also produced, but will be difficult to detect. Photons with energies less, similar1 MeV from shocks following neutron decay produce a characteristic signal which may be distinguishable from the proton-related MeV photons.

Measurements of the {sup 235}U(n,f) cross section in the 3 to 30 MeV neutron energy region

Energy Technology Data Exchange (ETDEWEB)

Carlson, A.D.; Wasson, O.A. [National Institute of Standards and Technology, Gaithersburg, MD (United States); Lisowski, P.W. [Los Alamos National Lab., NM (United States)] [and others

1991-12-31

To improve the accuracy of the {sup 235}U(n,f) cross section, measurements have been made of this standard cross section at the target 4 facility at Los Alamos National Laboratory (LANL). The data were obtained at the 20-meter flight path of that facility. The fission reaction rate was determined with a fast parallel plate ionization chamber and the neutron fluence was measured with an annular proton recoil telescope. The measurements provide the shape of the {sup 235}U(n,f) cross section relative to the hydrogen scattering cross section for neutron energies from about 3 to 30 MeV neutron energy. The data have been normalized to the very accurately known value near 14 MeV. The results are in good agreement with the ENDF/B-VI evaluation up to about 15 MeV neutron energy. Above this energy differences as large as 5% are observed.

Commercial cyclotrons. Part I: Commercial cyclotrons in the energy range 10 30 MeV for isotope production

Science.gov (United States)

Papash, A. I.; Alenitsky, Yu. G.

2008-07-01

A survey of commercial cyclotrons for production of medical and industrial isotopes is presented. Compact isochronous cyclotrons which accelerate negative hydrogen ions in the energy range 10 30 MeV have been widely used over the last 25 years for production of medical isotopes and other applications. Different cyclotron models for the energy range 10 12 MeV with moderate beam intensity are used for production of 11C, 13N, 15O, and 18F isotopes widely applied in positron emission tomography. Commercial cyclotrons with high beam intensity are available on the market for production of most medical and industrial isotopes. In this work, the physical and technical parameters of different models are compared. Possibilities of improving performance and increasing intensity of H- beams up to 2 3 mA are discussed.

Study of hadronic events and measurements of $\\alpha_{s}$ between 30 and 91 GeV

CERN Document Server

Acciarri, M; Aguilar-Benítez, M; Ahlen, S P; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alverson, G; Alviggi, M G; Ambrosi, G; Anderhub, H; Andreev, V P; Angelescu, T; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Baksay, L; Ball, R C; Banerjee, S; Banerjee, Sw; Banicz, K; Barczyk, A; Barillère, R; Barone, L; Bartalini, P; Baschirotto, A; Basile, M; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Bhattacharya, S; Biasini, M; Biland, A; Bilei, G M; Blaising, J J; Blyth, S C; Bobbink, Gerjan J; Böck, R K; Böhm, A; Boldizsar, L; Borgia, B; Boucham, A; Bourilkov, D; Bourquin, Maurice; Boutigny, D; Braccini, S; Branson, J G; Brigljevic, V; Brock, I C; Buffini, A; Buijs, A; Burger, J D; Burger, W J; Busenitz, J K; Cai, X D; Campanelli, M; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A M; Casaus, J; Castellini, G; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada-Canales, M; Cesaroni, F; Chamizo-Llatas, M; Chang, Y H; Chaturvedi, U K; Chekanov, S V; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chen, M; Chiefari, G; Chien, C Y; Cifarelli, Luisa; Cindolo, F; Civinini, C; Clare, I; Clare, R; Cohn, H O; Coignet, G; Colijn, A P; Colino, N; Commichau, V; Costantini, S; Cotorobai, F; de la Cruz, B; Csilling, Akos; Dai, T S; D'Alessandro, R; De Asmundis, R; Degré, A; Deiters, K; Denes, P; De Notaristefani, F; DiBitonto, Daryl; Diemoz, M; Van Dierendonck, D N; Di Lodovico, F; Dionisi, C; Dittmar, Michael; Dominguez, A; Doria, A; Dorne, I; Dova, M T; Drago, E; Duchesneau, D; Duinker, P; Durán, I; Dutta, S; Easo, S; Efremenko, Yu V; El-Mamouni, H; Engler, A; Eppling, F J; Erné, F C; Ernenwein, J P; Extermann, Pierre; Fabre, M; Faccini, R; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, Marta; Fenyi, B; Ferguson, T; Ferroni, F; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, Frank; Fisher, P H; Fisk, I; Forconi, G; Fredj, L; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gau, S S; Gentile, S; Gerald, J; Gheordanescu, N; Giagu, S; Goldfarb, S; Goldstein, J; Gong, Z F; Gougas, Andreas; Gratta, Giorgio; Grünewald, M W; Gupta, V K; Gurtu, A; Gutay, L J; Hartmann, B; Hasan, A; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Van Hoek, W C; Hofer, H; Hong, S J; Hoorani, H; Hou, S R; Hu, G; Innocente, Vincenzo; Janssen, H; Jenkes, K; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Kasser, A; Khan, R A; Kamrad, D; Kamyshkov, Yu A; Kapustinsky, J S; Karyotakis, Yu; Kaur, M; Kienzle-Focacci, M N; Kim, D; Kim, D H; Kim, J K; Kim, S C; Kim, Y G; Kinnison, W W; Kirkby, A; Kirkby, D; Kirkby, Jasper; Kiss, D; Kittel, E W; Klimentov, A; König, A C; Kopp, A; Korolko, I; Koutsenko, V F; Krämer, R W; Krenz, W; Kunin, A; Ladrón de Guevara, P; Landi, G; Lapoint, C; Lassila-Perini, K M; Laurikainen, P; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Leggett, C; Le Goff, J M; Leiste, R; Leonardi, E; Levchenko, P M; Li Chuan; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lu, W; Lü, Y S; Lübelsmeyer, K; Luci, C; Luckey, D; Luminari, L; Lustermann, W; Ma Wen Gan; Maity, M; Majumder, G; Malgeri, L; Malinin, A; Maña, C; Mangeol, D J J; Mangla, S; Marchesini, P A; Marin, A; Martin, J P; Marzano, F; Massaro, G G G; McNally, D; Mele, S; Merola, L; Meschini, M; Metzger, W J; Von der Mey, M; Mi, Y; Mihul, A; Van Mil, A J W; Mirabelli, G; Mnich, J; Molnár, P; Monteleoni, B; Moore, R; Morganti, S; Moulik, T; Mount, R; Müller, S; Muheim, F; Muijs, A J M; Nahn, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Niessen, T; Nippe, A; Nisati, A; Nowak, H; Oh, Yu D; Opitz, H; Organtini, G; Ostonen, R; Palomares, C; Pandoulas, D; Paoletti, S; Paolucci, P; Park, H K; Park, I H; Pascale, G; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Peach, D; Pei, Y J; Pensotti, S; Perret-Gallix, D; Petersen, B; Petrak, S; Pevsner, A; Piccolo, D; Pieri, M; Pinto, J C; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Postema, H; Produit, N; Prokofev, D; Prokofiev, D O; Rahal-Callot, G; Raja, N; Rancoita, P G; Rattaggi, M; Raven, G; Razis, P A; Read, K; Ren, D; Rescigno, M; Reucroft, S; Van Rhee, T; Riemann, S; Riles, K; Rind, O; Robohm, A; Rodin, J; Roe, B P; Romero, L; Rosier-Lees, S; Rosselet, P; Van Rossum, W; Roth, S; Rubio, Juan Antonio; Ruschmeier, D; Rykaczewski, H; Salicio, J; Sánchez, E; Sanders, M P; Sarakinos, M E; Sarkar, S; Sassowsky, M; Sauvage, G; Schäfer, C; Shchegelskii, V; Schmidt-Kärst, S; Schmitz, D; Schmitz, P; Schneegans, M; Scholz, N; Schopper, Herwig Franz; Schotanus, D J; Schwenke, J; Schwering, G; Sciacca, C; Sciarrino, D; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shukla, J; Shumilov, E; Shvorob, A V; Siedenburg, T; Son, D; Sopczak, André; Soulimov, V; Smith, B; Spillantini, P; Steuer, M; Stickland, D P; Stone, H; Stoyanov, B; Strässner, A; Strauch, K; Sudhakar, K; Sultanov, G G; Sun, L Z; Susinno, G F; Suter, H; Swain, J D; Tang, X W; Tauscher, Ludwig; Taylor, L; Ting, Samuel C C; Ting, S M; Tonutti, M; Tonwar, S C; Tóth, J; Tully, C; Tuchscherer, H; Tung, K L; Uchida, Y; Ulbricht, J; Uwer, U; Valente, E; Van de Walle, R T; Vesztergombi, G; Vetlitskii, I; Viertel, Gert M; Vivargent, M; Völkert, R; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Vorvolakos, A; Wadhwa, M; Wallraff, W; Wang, J C; Wang, X L; Wang, Z M; Weber, A; Wittgenstein, F; Wu, S X; Wynhoff, S; Xu, J; Xu, Z Z; Yang, B Z; Yang, C G; Yao, X Y; Ye, J B; Yeh, S C; You, J M; Zalite, A; Zalite, Yu; Zemp, P; Zeng, Y; Zhang, Z; Zhang, Z P; Zhou, B; Zhou, Y; Zhu, G Y; Zhu, R Y; Zichichi, Antonino; Ziegler, F

1997-01-01

We have studied the structure of hadronic events with a hard, %radiated isolated photon in the final state ($\\mathrm{e^{+}e^{-}} \\rightarrow$ Z $\\rightarrow$ hadrons $+$ $\\gamma$) in the 3.6 million hadronic data collected with the L3 detector at centre-of-mass energies around 91 GeV. The centre-of-mass energy of the hadronic system is in the range 30 GeV to 86 GeV. Event shape variables have been measured at these reduced centre-of-mass energies and have been compared with the predictions of different QCD Monte Carlo programs. The event shape variables and the energy dependence of their mean values are well reproduced by QCD models. We fit distributions of several global event shape variables to resummed $\\cal{O}

A 30 MeV H- cyclotron for isotope production

International Nuclear Information System (INIS)

Baartman, R.; Kleevan, W.J.; Laxdal, R.E.; Milton, B.F.; Otter, A.J.; Pearson, J.B.; Poirier, R.L.; Schmor, P.W.; Schneider, H.R.; Erdman, K.L.; Walker, Q.

1989-01-01

Because of an expanding market for radioisotopes there is a need for a new generation of cyclotrons designed specifically for this purpose. We describe such a cyclotron currently under construction. It is a 30 MeV H - design that exploits a newly developed high brightness multicusp ion source which is capable of H - currents of up to 5 mA. This together with careful beam matching then makes feasible accelerated H - beam intensities of 500 μA. The cyclotron being built is a four sector radial ridge design with two 45 degree dees in opposite valleys. Beam extraction is by stripping to H + in a thin graphite foil. Two extraction probes will allow simultaneous extraction of two beams, each with an intensity of up to 200 μA. Energy variation from 15 MeV to 30 MeV is achieved by varying the radial position of the extraction foil. 7 refs., 4 figs., 1 tab

Neutron and gamma-ray emission double differential cross sections for the nuclear reaction by 1.5 GeV {pi}{sup +} incidence

Energy Technology Data Exchange (ETDEWEB)

Iga, Kiminori; Ishibashi, Kenji; Shigyo, Nobuhiro [Kyushu Univ., Fukuoka (Japan)] [and others

1998-03-01

Neutron and gamma-ray production double differential cross sections were measured for iron by the use of 1.5 GeV {pi}{sup +} mesons. The measured cross sections were compared with the calculated values by HETC-KFA2. For the neutrons, the calculated results deviate from the experimental data in the neutron energy region below 30 MeV. The calculated values of gamma-ray production agree with the experimental data at gamma-ray energies from 1 to 7 MeV within a factor of three. (author)

Commissioning of the 123 MeV injector for 12 GeV CEBAF

International Nuclear Information System (INIS)

Wang, Yan; Hofler, Alicia S.; Kazimi, Reza

2015-09-01

The upgrade of CEBAF to 12GeV included modifications to the injector portion of the accelerator. These changes included the doubling of the injection energy and relocation of the final transport elements to accommodate changes in the CEBAF recirculation arcs. This paper will describe the design changes and the modelling of the new 12GeV CEBAF injector. Stray magnetic fields have been a known issue for the 6 GeV CEBAF injector, the results of modelling the new 12GeV injector and the resulting changes implemented to mitigate this issue are described in this paper. The results of beam commissioning of the injector are also presented.

Low energy spread 100 MeV-1 GeV electron bunches from laser wakefield acceleration at LOASIS

International Nuclear Information System (INIS)

Geddes, C.G.R.; Esarey, E.; Michel, P.; Nagler, B.; Nakamura, K.; Plateau, G.R.; Schroeder, C.B.; Shadwick, B.A.; Toth, Cs.; Van Tilborg, J.; Leemans, W.P.; Hooker, S.M.; Gonsalves, A.J.; Michel, E.; Cary, J.R.; Bruhwiler, D.

2006-01-01

Experiments at the LOASIS laboratory of LBNL recently demonstrated production of 100 MeV electron beams with low energy spread and low divergence from laser wakefield acceleration. The radiation pressure of a 10 TW laser pulse guided over 10 diffraction ranges by a plasma density channel was used to drive an intense plasma wave (wakefield), producing acceleration gradients on the order of 100 GV/m in a mm-scale channel. Beam energy has now been increased from 100 to 1000 MeV by using a cm-scale guiding channel at lower density, driven by a 40TW laser, demonstrating the anticipated scaling to higher beam energies. Particle simulations indicate that the low energy spread beams were produced from self trapped electrons through the interplay of trapping, loading, and dephasing. Other experiments and simulations are also underway to control injection of particles into the wake, and hence improve beam quality and stability further

Generation and application of 15 to 30 MeV parametric X-ray by linac

CERN Document Server

Akimoto, T

2002-01-01

15 to 30 MeV parametric X-ray (PXR) was generated using Si single crystal by 45 MeV electron LINAC. To obtain good monochromatic hard X-ray field, the appropriate conditions were determined by theoretical analysis and experiments. The intensity of PXR was increased with increasing electron energy and crystal rotation angle. However, PXR energy is independent of electron energy. By increasing measurement angle, energy of PXR decreased, but its intensity increased. 15 to 30 keV PXR energy and about 10 sup - sup 5 to 10 sup - sup 6 photon/electron of intensity were observed at 15 to 22 deg detection angle under the operation conditions of 45 MeV electron energy and 4 to 8 nA of beam current. The mass attenuation coefficient of photon of Zr, Nb and Mo, in K absorption edge was measured. Application to determine lattice distortion of target sample and off-angle of crystal was investigated. Generation and detection of PXR, measurement of characteristic properties: crystal rotation angle, detection angle, electron e...

Capture cross-section measurements for different elements at neutron energies between 0.5 and 3.0 MeV

International Nuclear Information System (INIS)

Grenier, Gerard; Voignier, Jacques; Joly, Serge.

1981-03-01

Neutron capture cross-sections have been measured for the nuclides: Rb, Y, Nb, Gd, W, Pt, Tl, and for the isotopes 155 Gd, 156 Gd, 157 Gd, 158 Gd, 160 Gd, 182 W, 183 W, 184 W, 186 W, 203 Tl and 205 Tl in the 0.5 MeV to 3.0 MeV neutron energy range. Neutron capture cross-sections are determined through direct γ-ray spectrum emitted by the sample. The gamma-rays are detected by a NaI scintillator surrounded by an annular NaI detector. The time-of-flight method is used. Our results are compared with previous data, evaluations and statistical model calculations [fr

Observation of a spin 4 neutral meson with 2 GeV mass decaying in $\\pi^{0} \\pi^{0}$

CERN Document Server

Apel, W D; Bertolucci, E.; Donskov, S.V.; Inyakin, A.V.; Kachanov, V.A.; Kittenberger, W.; Krasnokutsky, R.N.; Kruger, M.; Leder, G.; Lednev, A.A.; Mannelli, I.; Mikhailov, Yu.V.; Müller, H.; Pierazzini, G.M.; Prokoshkin, Yu.D.; Quaglia, M.; Schneider, H.; Scribano, A.; Sergiampietri, F.; Shuvalov, R.S.; Sigurdsson, G.; Steuer, M.; Vincelli, M.L.

1975-01-01

The invariant mass spectrum of neutral meson states from π−p interactions at 40 GeV/c incident momentum has been investigated in a high statistics experiment performed at the 70 GeV IHEP accelerator. To detect the high energy photons coming from the produced neutral states, a hodoscope spectrometer with a computer on-line was used. A clear structure on the mass spectrum of dipions produced in the reaction π−p→π°π°n is observed at 2 GeV. The decay angular distributions show in this mass region the variation with mass typical of a state with a spin J = 4. The mass of the observed meson is found to be M = (2020±30)MeV and the estimate of the full width is (180±60) MeV.

The MAGIC telescope for gamma-ray astronomy above 30 GeV

Science.gov (United States)

Moralejo, A.; MAGIC Collaboration

The MAGIC telescope is presently at its commissioning phase at the Roque de los Muchachos Observatory (ORM) on the island of La Palma. MAGIC will become the largest ground-based gamma ray telescope in the world, being sensitive to photons of energies as low as 30 GeV. The spectral range between 10 and 300 GeV remains to date mostly unexplored. Observations in this region of the spectrum are expected to provide key data for the understanding of a wide variety of astrophysical phenomena belonging to the so-called ``non thermal Universe'', like the processes in the nuclei of active galaxies, the radiation mechanisms of pulsars and supernova remnants, and the enigmatic gamma-ray bursts. And overview of the telescope and its Physics goals is presented.

Energy loss of muons in the energy range 1-10000 GeV

International Nuclear Information System (INIS)

Lohmann, W.; Kopp, R.; Voss, R.

1985-01-01

A summary is given of the most recent formulae for the cross-sections contributing to the energy loss of muons in matter, notably due to electro-magnetic interactions (ionization, bremsstrahlung and electron-pair production) and nuclear interactions. Computed energy losses dE/dx are tabulated for muons with energy between 1 GeV and 10,000 GeV in a number of materials commonly used in high-energy physics experiments. In comparison with earlier tables, these show deviations that grow with energy and amount to several per cent at 200 GeV muon energy. (orig.)

Investigation of states in 30P via the 30Si(3He,t)30P reaction at 30 MeV

International Nuclear Information System (INIS)

Ramstein, B.; Rosier, L.H.; Paris-11 Univ., 91 - Orsay; Meijer, R.J. de

1981-01-01

The 30 Si( 3 He,t) 30 P reaction has been measured for about 100 levels in 30 P with Esub(x)<8.8 MeV. Little selectivity in the population of states has been observed. For 75 levels angular distributions have been analysed using a 'fingerprint method' by determining the L-value from a comparison in shape with transition to states with known Jsup(π). For possible mixed L-transitions a dominance of the higher L-value is observed for almost all cases. Coulomb displacement energy calculations utilizing shell-model wave functions have been used to identify T=1 states

Beam dynamics study of a 30 MeV electron linear accelerator to drive a neutron source

Science.gov (United States)

Kumar, Sandeep; Yang, Haeryong; Kang, Heung-Sik

2014-02-01

An experimental neutron facility based on 32 MeV/18.47 kW electron linac has been studied by means of PARMELA simulation code. Beam dynamics study for a traveling wave constant gradient electron accelerator is carried out to reach the preferential operation parameters (E = 30 MeV, P = 18 kW, dE/E E-gun, pre-buncher, buncher, and 2 accelerating columns. A disk-loaded, on-axis-coupled, 2π/3-mode type accelerating rf cavity is considered for this linac. After numerous optimizations of linac parameters, 32 MeV beam energy is obtained at the end of the linac. As high electron energy is required to produce acceptable neutron flux. The final neutron flux is estimated to be 5 × 1011 n/cm2/s/mA. Future development will be the real design of a 30 MeV electron linac based on S band traveling wave.

Evaluation of neutron- and proton-induced cross sections of {sup 27}Al up to 2 GeV

Energy Technology Data Exchange (ETDEWEB)

Lee, Young-Ouk; Chang, Jonghwa [Korea Atomic Energy Research Institute, Yusung, Taejon (Korea, Republic of); Fukahori, Tokio; Chiba, Satoshi

1999-03-01

We have evaluated neutron and proton nuclear data of {sup 27}Al for energies up to 2 GeV. The best set of optical model parameters were obtained above 20 MeV for neutron and above reaction threshold for proton up to 250 MeV with the phenomenological potential forms proposed by Chiba. The transmission coefficients for neutron and proton derived from the optical models are fed into the GNASH code system to calculate angle-energy correlated emission spectra for light ejectiles and gamma rays. For energies above 250 MeV and below 2 GeV, the total, reaction and elastic scattering cross sections were evaluated by an empirical fit and recent systematics. Emitted nucleon and pion were estimated by use of QMD + SDM (Quantum Molecular Dynamics + Statistical Decay Model). (author)

Analysis of NN amplitudes up to 2.5 GeV: an optical model and geometric interpretation

International Nuclear Information System (INIS)

Geramb, H.V. von; Universitaet Hamburg, Hamburg,; Amos, K.A.; Labes, H.; Sander, M.

1998-01-01

We analyse the SM97 partial wave amplitudes for nucleon-nucleon (NN) scattering to 2.5 GeV, in which resonance and meson production effects are evident for energies above pion production threshold. Our analyses are based upon boson exchange or quantum inversion potentials with which the sub-threshold data are fit perfectly. Above 300 MeV they are extrapolations, to which complex short ranged Gaussian potentials are added in the spirit of the optical models of nuclear physics and of diffraction models of high energy physics. The data to 2.5 GeV are all well fit. The energy dependences of these Gaussians are very smooth save for precise effects caused by the known Δ and N* resonances. With this approach, we confirm that the geometrical implications of the profile function found from diffraction scattering are pertinent in the regime 300 MeV to 2.5 GeV and that the overwhelming part of meson production comes from the QCD sector of the nucleons when they have a separation of their centres of 1 to 1.2 fm. This analysis shows that the elastic NN scattering data above 300 MeV can be understood with a local potential operator as well as has the data below 300 MeV

Integral measurement of the $^{12}$C(n,p)$^{12}$B reaction up to 10 GeV

CERN Document Server

Žugec, P; Bosnar, D; Ventura, A; Mengoni, A; Altstadt, S; Andrzejewski, J; Audouin, L; Barbagallo, M; Bécares, V; Bečvář, F; Belloni, F; Berthoumieux, E; Billowes, J; Boccone, V; Brugger, M; Calviani, M; Calviño, F; Cano-Ott, D; Carrapiço, C; Cerutti, F; Chiaveri, E; Chin, M; Cortés, G; Cortés-Giraldo, M.A; Cosentino, L; Diakaki, M; Domingo-Pardo, C; Dressler, R; Duran, I; Eleftheriadis, C; Ferrari, A; Finocchiaro, P; Fraval, K; Ganesan, S; García, A R; Giubrone, G; Gómez-Hornillos, M B; Gonçalves, I F; González-Romero, E; Griesmayer, E; Guerrero, C; Gunsing, F; Gurusamy, P; Heinitz, S; Jenkins, D G; Jericha, E; Käppeler, F; Karadimos, D; Kivel, N; Kokkoris, M; Krtička, M; Kroll, J; Langer, C; Lederer, C; Leeb, H; Leong, L S; Meo, S Lo; Losito, R; Manousos, A; Marganiec, J; Martínez, T; Massimi, C; Mastinu, P; Mastromarco, M; Mendoza, E; Milazzo, P M; Mingrone, F; Mirea, M; Mondalaers, W; Musumarra, A; Paradela, C; Pavlik, A; Perkowski, J; Plompen, A; Praena, J; Quesada, J; Rauscher, T; Reifarth, R; Riego, A; Roman, F; Rubbia, C; Sarmento, R; Saxena, A; Schillebeeckx, P; Schmidt, S; Schumann, D; Tagliente, G; Tain, J L; Tarrío, D; Tassan-Got, L; Tsinganis, A; Valenta, S; Vannini, G; Variale, V; Vaz, P; Versaci, R; Vermeulen, M J; Vlachoudis, V; Vlastou, R; Wallner, A; Ware, T; Weigand, M; Weiß, C; Wright, T

2016-01-01

The integral measurement of the $^{12}$C(n,p)$^{12}$B reaction was performed at the neutron time of flight facility n_TOF at CERN. The total number of $^{12}$B nuclei produced per neutron pulse of the n_TOF beam was determined using the activation technique in combination with a time of flight technique. The cross section is integrated over the n_TOF neutron energy spectrum from reaction threshold at 13.6 MeV to 10 GeV. Having been measured up to 1 GeV on basis of the $^{235}$U(n,f) reaction, the neutron energy spectrum above 200 MeV has been reevaluated due to the recent extension of the cross section reference for this particular reaction, which is otherwise considered a standard up to 200 MeV. The results from the dedicated GEANT4 simulations have been used to evaluate the neutron flux from 1 GeV up to 10 GeV. The experimental results related to the $^{12}$C(n,p)$^{12}$B reaction are compared with the evaluated cross sections from major libraries and with the predictions of different GEANT4 models, which m...

Design and performance of the 40 MeV linac and beam transport system for the 1 GeV synchrotron radiation source at SORTEC

International Nuclear Information System (INIS)

Shiota, M.; Hiraki, A.; Mizota, M.; Iida, T.; Haraguchi, M.; Kuno, K.; Nakamura, S.; Ohno, M.; Tomimasu, T.

1990-01-01

A 1 Gev synchrotron radiation source (SOR) system has been installed and is now being adjusted at SORTEC corporation. This paper reports the configuration and the beam test results of the 40 MeV electron linac (pre-injector) and the beam transport line to the electron synchrotron used in this system. The output beam from the linac must be low emittance, small energy spread, and stable in energy. The beam transport line must also efficiently lead the beam from the linac to the electron synchrotron. This linac produced the beam current of 130 mA, with an energy spread of 1.3 % (FWHM), and an emittance of 0.7 πmm·mrad. The beam characteristics were verified by various beam monitors on the beam transport line. (author)

Impact parameter analysis of proton-antiproton elastic scattering from √s=7.6 GeV to √s=546 GeV

International Nuclear Information System (INIS)

Fearnley, T.

1985-09-01

The proton-antiproton elastic profile function GAMMA (b) and inelastic overlap function Gsub(in)(b) are calculated from a coherent set of proton-antiproton elastic scattering data at Psub(L)=30 and 50 GeV/c (√s=7.6 and 9.8 GeV), and at √s=53 and 546 GeV. The energy dependence of Gsub(in)(b) is studied in the low energy regime and in the high energy regime. The increase of the inelastic cross section from 50 GeV/c to 30 GeV/c and from √s=53 GeV to √s=546 GeV is found to originate from a peripheral increase of Gsub(in) around 1 fm, accompanied by a non-negligible central increase. The proton-antiproton collision at √s=53 GeV is shown to be slightly less absorptive centrally than pp at this energy, while it is more absorptive peripherally around 1.2 fm. The inelastic overlap functions strongly disagree with the predictions of geometrical scaling and factorizing eikonal models, both in the low energy regime psub(L)=30-50 GeV/c and in the high energy regime √s=53-546 GeV

The evaluation of H total cross section from 20 MeV to 2 GeV

Energy Technology Data Exchange (ETDEWEB)

Tingjin, Liu [Chinese Nuclear Data Center, Beijing, BJ (China)

1996-06-01

The H total cross section was evaluated in the neutron energy region from 20 to 2000 MeV. The recommended experimental data were fitted by using Spline fit program with knot optimization, the fit values are taken as recommended ones. The data are compared with those from ENDF/B-6 (<100 MeV), the differences are 0.5%{approx}2.0% from 20 to 40 MeV, and almost the same in the energy region 40{approx}100 MeV.

Specialized reactions: reactions at intermediate energies: Baryon--nucleus collisions, 150 MeV--1 GeV

International Nuclear Information System (INIS)

Igo, G.

1974-01-01

The high energy collision approximation proposed by Glauber to describe experimental data at the upper end of the intermediate range is reviewed. Some aspects of the model which limit its validity are outlined. Elastic scattering of protons from light nuclei is discussed in the framework of the Glauber model. For data in the energy region near 200 MeV, the plane wave impulse approximation (PWIA) and the distorted wave impulse approximation (DWIA) are applied. Quasielastic scattering is treated by considering (p,p') and (p,2p) reactions with light nuclei. A short discussion of the high resolution spectrometer facility at LAMPF and the SPES 1 facility at Saturne is given. (46 figures, 3 tables, 102 references) (U.S.)

Fusion with projectiles from carbon to argon at energies between 20A MeV and 60A MeV

International Nuclear Information System (INIS)

Galin, J.

1986-01-01

Fusion reactions are known to be the dominant reaction channel at low bombarding energies and can now be investigated with a large variety of projectiles at several tens of MeV per nucleon. The gross characteristics of the fusion process can be studied by measuring global quantities, such as the linear momentum transferred from projectile to target and the dissipated energy of the reaction. The strong correlation between these two quantities is demonstrated at moderate bombarding energies, with a Ne projectile on a U target. It is expected that light particle (charged or neutron) multiplicity measurements can be extended to this higher energy domain and be used to selectively filter these collisions, according to their degree of violence. A review of the linear momentum transfer is made, considering essentially heavy targets and two important parameters in the entrance channel: the projectile energy and its mass. Over a broad mass range, and for energies up to 30A MeV, the momentum transfer scales with the mass of the projectile. At 30A MeV, the most probable value of projectile momentum transferred to the fused system is 80%, and this represents roughly 180 MeV/c per projectile nucleon. At higher bombarding energies, the momentum distribution in the fused systems, as observed from binary fission events, seems to depend on the mass of the projectile. Further studies are still needed to understand this behavior. Finally, the decay of highly excited (E* similarly ordered 500-800 MeV) fused systems, with masses close to 270 amu, is studied from the characteristics of both fusion fragments and light charged particles. It is shown that thermal equilibrium is reached before fission, even for such high energy deposition. However, the decay sequence is sensitive to dynamical effects and does not depend only on available phase space

Conceptual design of 30 MeV magnet system used for BNCT epithermal neutron source

International Nuclear Information System (INIS)

Slamet Santosa; Taufik

2015-01-01

Conceptual design of 30 MeV Magnet System Used for BNCT Epithermal Neutron Source has been done based on methods of empirical model of basic equation, experiences of 13 MeV cyclotron magnet design and personal communications. In the field of health, cyclotron can be used as an epithermal neutron source for Boron Neutron Capture Therapy (BNCT). The development of cyclotron producing epithermal neutrons for BNCT has been performed at Kyoto University, of which it produces a proton beam current of 1.1 mA with energy of 30 MeV. With some experiences on 13 MeV cyclotron magnet design, to support BNCT research and development we performed the design studies of 30 MeV cyclotron magnet system, which is one of the main components of the cyclotron for deflecting proton beam into circular trajectory and serves as beam focusing. Results of this study are expected to define the parameters of particular cyclotron magnet. The scope of this study includes the study of the parameters component of the 30 MeV cyclotron and magnet initial parameters. The empirical method of basic equation model is then corroborated by a simulation using Superfish software. Based on the results, a 30 MeV cyclotron magnet for BNCT neutron source enables to be realized with the parameters of B 0 = 1.06 T, frequency RF = 64.733938 ≈ 65 MHz, the external radius of 0.73 m, the radius of the polar = 0.85 m, BH = 1.95 T and a gap hill of 4 cm. Because proton beam current that be needed for BNCT application is very large, then in the calculation it is chosen a great focusing axial νz = 0.630361 which can generate B V = 0.44 T. (author)

Fission of {sup 209}Bi and {sup 197}Au nuclei induced by 30 MeV protons

Energy Technology Data Exchange (ETDEWEB)

Noshad, Houshyar; Soheyli, Saeed [Amir-Kabir University of Technology, Physics and Nuclear Science Department, Tehran (Iran); Lamehi-Rachti, Mohammad [Atomic Energy Organization of Iran (AEOI), Nuclear Research Center, Van de Graaff Laboratory, Tehran (Iran)

2001-10-01

Thin targets of {sup 209}Bi and {sup 197}Au were bombarded with 30 MeV protons at the Cyclotron Department of Nuclear Research Center for Agriculture and Medicine (NRCAM). Correlated measurements of kinetic energies of fission fragment pairs, and their time-of-flights were made using pair spectrometry. The fission cross sections, fragment mass distributions, and total kinetic energy distributions of the fragments were measured in our experiment. The accurate values of cross sections for fission of {sup 209}Bi and {sup 197}Au nuclei with 30 MeV protons were obtained to be 1,100{+-}100 and 62{+-}5.6 {mu}b, respectively. The cross section of {sup 209}Bi fission with its associated error, through using this method, has not been reported previously. The interpretation in terms of liquid-drop model of fissioning nucleus {sup 210}Po at the excitation energy of 35 MeV was confirmed by the dispersion of the distribution in fragment mass for bismuth fission. (author)

Photoproduction of π+π-π0 on hydrogen with linearly polarized photons of energy 20-70 GeV

International Nuclear Information System (INIS)

Lasalle, J.C.; Patrick, G.N.; Storr, K.M.; Atkinson, M.; Axon, T.J.; Barberis, D.; Brodbeck, T.J.; Brookes, G.R.; Bunn, J.J.; Bussey, P.J.; Clegg, A.B.; Dainton, J.B.; Davenport, M.; Dickinson, B.; Dieckmann, B.; Donnachie, A.; Ellison, R.J.; Flower, P.; Flynn, P.J.; Galbraith, W.; Heinloth, K.; Henderson, R.C.W.; Hughes-Jones, R.E.; Hutton, J.S.; Ibbotson, M.; Jakob, H.P.; Jung, M.; Kemp, M.A.R.; Kumar, B.R.; Laberrigue, J.; Lafferty, G.D.; Lane, J.B.; Levy, J.M.; Liebenau, V.; McClatchey, R.H.; Mercer, D.; Morris, J.A.G.; Morris, J.V.; Newton, D.; Paterson, C.; Paul, E.; Raine, C.; Reidenbach, M.; Rotscheidt, H.; Schloesser, A.; Sharp, P.H.; Skillicorn, I.O.; Smith, K.M.; Thompson, R.J.; Vaissiere, C. de la; Waite, A.P.; Worsell, M.F.; Yiou, T.P.

1984-01-01

Results on photoproduction of π + π - π 0 in the photon energy range 20-70 GeV are presented. For the ω meson, the production cross-section is found to be 1010 +- 15 (statistical) +- 290 (systematic) nb and is constant over the incident photon energy range. Spin-density matrix elements are evaluated for ω meson production. The PHI meson is observed with a total photoproduction cross section (corrected for branching ratio to π + π - π 0 ) of 610 +- 35 +- 170 nb. A third resonance, at 1.67 GeV, is seen in the mass spectrum and its interpretation is discussed. The production of a braod π + π - π 0 continuum, mainly via rhoπ, and peaking at 1.2 GeV, contributes with a cross section of about 2.5 μb. The spin-parity content is analysed by the moments of the π + π - π 0 decay angular distribution in the helicity frame and by maximum likelihood fits to the π + π - π 0 Dalitz plot. It is found that production of Jsup(P) = 1 - states accounts for less than half of the total mass spectrum above 900 MeV. There is a broad enhancement in the 1 + wave around 1.15 GeV indicating photoproduction of the H(1190) meson. (orig.)

Polarized beam asymmetry for. gamma. d. -->. Peta in the energy range 0. 4-0. 8 GeV

Energy Technology Data Exchange (ETDEWEB)

Adamyan, F.V.; Arustamyan, G.V.; Galumyan, P.I.; Grabsky, V.H.; Hakopyan, H.H.; Karapetyan, V.V.; Vartapetyan, H.A.

1983-01-01

Measurements of the polarized beam asymmetry for deuteron photodisintegration ..gamma..d ..-->.. Peta have been carried out in the energy range E/sub ..gamma../ = 0.4-0.8 GeV and at angles theta/sub p//sup cm/ = 45/sup 0/-75/sup 0/. The results obtained are in disagreement with theoretical predictions which take into account the dibaryon resonance contribution. The data qualitative analysis indicates the weakness of isoscalar dibaryon amplitudes near E/sub ..gamma../ = 400 MeV. 8 references, 1 figure.

Measurement of neutron-induced fission cross-sections of Th232, U238, U233 and Np237 relative to U235 from 1 MeV to 200 MeV

Energy Technology Data Exchange (ETDEWEB)

Shcherbakov, O.A.; Laptev, A.B.; Petrov, G.A. [Petersburg Nuclear Physics Inst., Gatchina, Leningrad district (Russian Federation); Fomichev, A.V.; Donets, A.Y.; Osetrov, O.I.

1998-11-01

The measurements of neutron-induced cross-section ratios for Th232, U238, U233 and Np237 relative to U235 have been carried out in the energy range from 1 MeV up to 200 MeV using the neutron time-of-flight spectrometer GNEIS based on 1 GeV proton synchrocyclotron. Below 20 MeV, the results of present measurements are roughly in agreement with evaluated data though there are some discrepances to be resolved. (author)

Reconstruction of GeV Neutrino Events in LENA

International Nuclear Information System (INIS)

Moellenberg, R.; Feilitzsch, F. von; Goeger-Neff, M.; Hellgartner, D.; Lewke, T.; Meindl, Q.; Oberauer, L.; Potzel, W.; Tippmann, M.; Winter, J.; Wurm, M.; Peltoniemi, J.

2011-01-01

LENA (Low Energy Neutrino Astronomy) is a proposed next generation liquid-scintillator detector with about 50 kt target mass. Besides the detection of solar neutrinos, geoneutrinos, supernova neutrinos and the search for the proton decay, LENA could also be used as the far detector of a next generation neutrino beam. The present contribution outlines the status of the Monte Carlo studies towards the reconstruction of GeV neutrinos in LENA. Both the tracking capabilities at a few hundred MeV, most interesting for a beta beam, and above 1 GeV for a superbeam experiment are presented.

Activation cross sections of deuteron induced reactions on niobium in the 30–50 MeV energy range

International Nuclear Information System (INIS)

Ditrói, F.; Tárkányi, F.; Takács, S.; Hermanne, A.; Ignatyuk, A.V.

2016-01-01

Highlights: • Deuteron induced nuclear reactions on natural niobium up to 50 MeV. • Stacked foil irradiation technique. • Comparison of results with the ALICE-D, EMPIRE-D and TENDL-2015 calculations. • Application of radioisotopes in medicine and industry. - Abstract: Activation cross-sections of deuterons induced reactions on Nb targets were determined with the aim of different applications and comparison with theoretical models. We present the experimental excitation functions of "9"3Nb(d,x)"9"3"m","9"0Mo, "9"2"m","9"1"m","9"0Nb, "8"9","8"8Zr and "8"8","8"7"m","8"7"gY in the energy range of 30–50 MeV. The results were compared with earlier measurements and with the cross-sections calculated by means of the theoretical model codes ALICE-D, EMPIRE-D and TALYS (on-line TENDL-2014 and TENDL-2015 libraries). Possible applications of the radioisotopes are discussed in detail.

Determination of 40Ca and 48Ca matter densities by 600 MeV and 1 GeV proton elastic scattering

International Nuclear Information System (INIS)

Brissaud, I.; Campi, X.

1979-02-01

The 600MeV and 1GeV data of proton elastic scattering on 40 Ca and 48 Ca have been analyzed in the framework of the Glauber model. The matter distributions are extracted from the data in an approximately model-independent form based on a Fourier series expansion. A similar method is used to deduce directly the 48 Ca- 40 Ca neutron density difference

SCINFUL-QMD: Monte Carlo based computer code to calculate response function and detection efficiency of a liquid organic scintillator for neutron energies up to 3 GeV

International Nuclear Information System (INIS)

Satoh, Daiki; Sato, Tatsuhiko; Shigyo, Nobuhiro; Ishibashi, Kenji

2006-11-01

The Monte Carlo based computer code SCINFUL-QMD has been developed to evaluate response function and detection efficiency of a liquid organic scintillator for neutrons from 0.1 MeV to 3 GeV. This code is a modified version of SCINFUL that was developed at Oak Ridge National Laboratory in 1988, to provide a calculated full response anticipated for neutron interactions in a scintillator. The upper limit of the applicable energy was extended from 80 MeV to 3 GeV by introducing the quantum molecular dynamics incorporated with the statistical decay model (QMD+SDM) in the high-energy nuclear reaction part. The particles generated in QMD+SDM are neutron, proton, deuteron, triton, 3 He nucleus, alpha particle, and charged pion. Secondary reactions by neutron, proton, and pion inside the scintillator are also taken into account. With the extension of the applicable energy, the database of total cross sections for hydrogen and carbon nuclei were upgraded. This report describes the physical model, computational flow and how to use the code. (author)

Evaluated Nuclear Data Library for Transport Calculations at Energies up to 150 MeV

International Nuclear Information System (INIS)

Korovin, Yu.A.; Konobeyev, A.Yu.; Pilnov, G.B.; Stankovskiy, A.Yu.

2005-01-01

A new evaluated nuclear data library has been created. The library consists of two sub-libraries for neutron and proton incident particles. The first version of neutron sub-library has been completed and described in the present paper. The library contains nuclear data for transport, heating, and shielding applications for 242 nuclides ranging in atomic number from 8 to 82 in the energy region of primary neutrons from 10-5 eV to 150 MeV. Data below 20 MeV are taken mainly from ENDF/B-VI (Revision 8) and for some nuclides, from the JENDL-3.3 and JEFF-3.0 libraries. The evaluation of emitted particle energy and angular distributions at the energies above 20 MeV was performed with the help of the ALICE/ASH code and the analysis of available experimental data. The total cross sections, elastic cross sections, and elastic scattering angular distributions were calculated with the help of the coupled channel model. The results of the calculation were adjusted to the data from ENDF/B-VI, JENDL-3.3m or JEFF-3.0 at the neutron energy equal to 20 MeV. The library is written in ENDF/B-VI format using the MF=3/MT=5 and MF=6/MT=5 representations

Fission cross sections of {sup 235,238}U and {sup 209}Bi at incident proton energies above 70 MeV

Energy Technology Data Exchange (ETDEWEB)

Obukhov, A I; Rimskij-Korsakov, A A; Eismont, V P [V.G. Khlopin Radium Inst., St. Petersburg (Russian Federation)

1997-06-01

The proton fission cross-section data of {sup 235,238}U and Bi were measured in the V.G. Khlopin Radium Institute over a wide proton energy range. The experimental and calculated data were also compared with experimental neutron values. The proton cross-section of {sup 235,238}U increased up to 60-70 MeV and then decreased. The bismuth proton fission cross-section increased in line with the rise in proton energy up to 1 GeV. (author). 21 refs, 6 figs.

Cosmic-ray positron fraction measurement from 1 to 30 GeV with AMS-01

CERN Document Server

Aguilar, M; Allaby, James V; Alpat, B; Ambrosi, G; Anderhub, H; Ao, L; Arefev, A; Azzarello, P; Baldini, L; Basile, M; Barancourt, D; Barão, F; Barbier, G; Barreira, G; Battiston, R; Becker, R; Becker, U; Bellagamba, L; Bene, P; Berdugo, J; Berges, P; Bertucci, B; Biland, A; Blasko, S; Bölla, G; Boschini, M; Bourquin, M; Brocco, L; Bruni, G; Buénerd, M; Burger, J D; Burger, W J; Cai, X D; Camps, C; Cannarsa, P; Capell, M; Cardano, F; Casadei, D; Casaus, J; Castellini, G; Chang, Y H; Chen, H F; Chen, H S; Chen, Z G; Chernoplekov, N A; Tzi Hong Chiueh; Cho, K; Choi, M J; Choi, Y Y; Cindolo, F; Commichau, V; Contin, A; Cortina, E; Cristinziani, M; Dai, T S; Delgado, C; Difalco, S; Djambazov, L; D'Antone, I; Dong, Z R; Emonet, P; Engelberg, J; Eppling, F J; Eronen, T; Esposito, G; Extermann, P; Favier, Jean; Fiandrini, E; Fisher, P H; Flügge, G; Fouque, N; Galaktionov, Yu; Gast, H; Gervasi, M; Giusti, P; Grandi, D; Grimm, O; Gu, W Q; Hangarter, K; Hasan, A; Hermel, V; Hofer, H; Hungerford, W; Jongmanns, M; Karlamaa, K; Karpinski, W; Kenney, G; Kim, D H; Kim, G N; Kim, K S; Kim, M Y; Klimentov, A; Kossakowski, R; Kounine, A; Koutsenko, V F; Kraeber, M; Laborie, G; Laitinen, T; Lamanna, G; Lanciotti, E; Laurenti, G; Lebedev, A; Lechanoine-Leluc, C; Lee, M W; Lee, S C; Levi, G; Liu, C L; Liu, H T; Lu, G; Lü, Y S; Lübelsmeyer, K; Luckey, D; Lustermann, W; Maña, C; Margotti, A; Mayet, F; McNeil, R R; Meillon, B; Menichelli, M; Mihul, A; Mujunen, A; Oliva, A; Olzem, J; Palmonari, F; Park, H B; Park, W H; Pauluzzi, M; Pauss, F; Perrin, E; Pesci, A; Pevsner, A; Pilo, F; Pimenta, M; Plyaskin, V; Pozhidaev, V; Pohl, M; Produit, N; Rancoita, P G; Rapin, D; Raupach, F; Ren, D; Ren, Z; Ribordy, M; Richeux, J P; Riihonen, E; Ritakari, J; Ro, S; Röser, U; Rossin, C; Sagdeev, R; Santos, D; Sartorelli, G; Sbarra, C; Schael, S; Schultzvon Dratzig, A; Schwering, G; Seo, E S; Shin, J W; Shoumilov, E; Shoutko, V; Siedenburg, T; Siedling, R; Son, D; Song, T; Spinella, F; Steuer, M; Sun, G S; Suter, H; Tang, X W; Ting, Samuel C C; Ting, S M; Tornikoski, M; Torsti, J; Trumper, J; Ulbricht, J; Urpo, S; Valtonen, E; Vandenhirtz, J; Velikhov, E P; Verlaat, B; Vetlitskii, I; Vezzu, F; Vialle, J P; Viertel, G; Vite, D; Von Gunten, H; Waldmeier-Wicki, S; Wallraff, W; Wang, B C; Wang, J Z; Wiik, K; Williams, C; Wu, S X; Xia, P C; Xu, S; Yan, J L; Yan, L G; Yang, C G; Yang, J; Yang, M; Ye, S W; Xu, Z Z; Zhang, H Y; Zhang, Z P; Zhao, D X; Zhou, Y; Zhu, G Y; Zhu, W Z; Zhuang, H L; Zichichi, A; Zimmermann, B; Zuccon, P

2007-01-01

A measurement of the cosmic ray positron fraction e+/(e+ + e-) in the energy range of 1-30 GeV is presented. The measurement is based on data taken by the AMS-01 experiment during its 10 day Space Shuttle flight in June 1998. A proton background suppression on the order of 10^6 is reached by identifying converted bremsstrahlung photons emitted from positrons.

Cosmic-ray positron fraction measurement from 1 to 30 GeV with AMS-01

International Nuclear Information System (INIS)

Aguilar, M.; Alcaraz, J.; Allaby, J.

2007-01-01

A measurement of the cosmic ray positron fraction e + /(e + +e - ) in the energy range of 1-30 GeV is presented. The measurement is based on data taken by the AMS-01 experiment during its 10 day Space Shuttle flight in June 1998. A proton background suppression on the order of 10 6 is reached by identifying converted bremsstrahlung photons emitted from positrons

Evaluation of cross sections of 56Fe up to 3 GeV and integral benchmark calculation for thick target yield

International Nuclear Information System (INIS)

Yoshizawa, Nobuaki; Meigo, Shin-ichiro

2001-01-01

The neutron and proton cross sections of 56 Fe were evaluated up to 3 GeV. JENDL High Energy File of 56 Fe were developed for use in transport calculation. For neutrons, the high-energy data are merged with JENDL3.3-file. Integral benchmark calculations for thick target neutron yields (TTY) for 113 MeV and 256 MeV proton bombardment of Fe targets were performed using the evaluated libraries. Calculated TTY neutron spectra were compared with experimental data. For 113 MeV, calculated TTY at 7.5 degree underestimated in the emitted neutron energy range above 10 MeV. For 256 MeV, calculated TTY well agree with experimental data except below 10 MeV. (author)

Conversion efficiency of lead for 30-200 MeV photons

International Nuclear Information System (INIS)

Darriulat, P.; Gygi, E.; Holder, M.; McDonald, K.T.; Pugh, H.G.; Schneider, F.; Tittel, K.

1975-01-01

The conversion efficiency of lead has been measured as a function of thickness for 44 MeV, 94 MeV and 177 MeV photons, and as a function of energy between 29 MeV and 177 Mev for thickness of one and two radiation lengths. Some additional information on multiplicity of secondary tracks and on their angular distribution was obtained using a small streamer chamber. The results obtained confirm the shower calculations of Messel and Crawford. (Auth.)

Theoretical calculation of n + {sup 59}Co reaction in energy region up to 100 MeV

Energy Technology Data Exchange (ETDEWEB)

Qingbiao, Shen; Baosheng, Yu; Dunjiu, Cai [Chinese Nuclear Data Center, Beijing, BJ (China)

1996-06-01

A set of neutron optical potential parameters for {sup 59}Co in energy region of 2{approx}100 MeV was obtained based on concerned experimental data. Various cross sections of n + {sup 59}Co reactions were calculated and predicted. The calculated results show that the activation products {sup 58,57}Co, {sup 59}Fe and {sup 56}Mn are main neutron monitor reaction products for n + {sup 59}Co reaction in energy range up to 100 MeV. {sup 54}Mn production reaction can be a promising neutron monitor reaction in the energy region from 30 to 100 MeV. (6 figs.).

P-barp and pp elastic scattering from 10 GeV to 1000 GeV centre-of-mass energy

International Nuclear Information System (INIS)

Islam, M.M.; Fearnley, T.; Guillaud, J.P.

1984-01-01

Antiproton-proton and proton-proton elastic scattering are studied simultaneously over the energy range √s approx. (10-1000) GeV in a nucleon valence core model proposed earlier. The scattering is described as primarily due to two processes: diffraction and hard scattering. The latter originates from the scattering of a nucleon core off another core. Destructive interference between the two processes produces dips in p-barp and pp differential cross-sections. As energy increases beyond the ISR range (√s = (23-62) GeV), the dips get filled up, and eventually transform into shoulders or breaks at collider energies. Differences between p-barp and pp differential cross-sections persist even at collider energies. Comparison with ISR data shows that the model provides a quantitative description of pp elastic scattering in this energy range. Predictions of p-barp and pp differential cross-sections at future collider energies √s = 800 and 2000 GeV are given. In order to distinguish between competing models, need for measuring the p-barp differential cross-section at the ISR and SPS collider in the abs (t)-range (0.5-2.0) (GeV) 2 is stressed

Contribution to {pi}{sup +}p inelastic scattering at incoming pion energies near 1 GeV; Contribution a la diffusion inelastique {pi}{sup +}p pour des energies du {pi} incident voisines de 1 GeV

Energy Technology Data Exchange (ETDEWEB)

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

1968-06-01

Results on {pi}{sup +}p scattering at 810 and 1300 MeV incoming kinetic energy are presented. In the three-body final states ({pi}{sup +}p {yields} {pi}{sup +}{pi}{sup 0}p or {pi}{sup +}{pi}{sup +}n) the N{sup *}{sub 33} production is strongly dominant. At 1300 MeV one also observes the {rho}, N{sup *}{sub 1/2} {sub 3/2} and N{sup *}{sub 1/2} {sub 5/2} productions. The difficulty in correctly separating these channels demands trying a more general analysis, taking simultaneously into account several processes (N{sup *}{pi}, {rho}N,...). A generalized isobaric model is discussed. Assuming the interaction of particles by pairs, we can carry out a partial wave analysis of the three body final state reactions. The expansion of the differential cross section in spherical harmonics for data between 600 and 1460 MeV (compilation of data from different laboratories) leads to a simple discussion of the angular effects for different parts of the Dalitz plot. A partial wave analysis has been made below 1 GeV. The reaction p {pi}{sup +}{pi}{sup 0} is correctly explained by considering only the N{sup *}{sub 33} production. The different partial waves are in agreement with the elastic phase shift analysis, except for the wave SD1 (corresponding to the elastic wave S31) which is found to be small. Therefore, the S31 resonance appears weakly coupled to the N{sup *}{sub 33}-{pi} channel. (author) [French] Les resultats de la mesure de la diffusion {pi}{sup +}p pour des energies cinetiques du {pi} incident egales a 810 MeV et 1300 MeV sont presentes. Dans les reactions a trois corps, {pi}{sup +}p {yields} {pi}{sup +}{pi}{sup 0}p ou {pi}{sup +}{pi}{sup +}n, la production de l'isobare 3/2 3/2 est fortement dominante. A 1300 MeV, on observe egalement la production du {rho} et des isobares 1/2 3/2 et 1/2 5/2. L'impossibilite de separer correctement ces differentes productions demande de chercher a effectuer l'analyse des donnees sous une forme plus generale permettant de tenir compte

Comparison of Bonner sphere responses calculated by different Monte Carlo codes at energies between 1 MeV and 1 GeV – Potential impact on neutron dosimetry at energies higher than 20 MeV

CERN Document Server

Rühm, W; Pioch, C; Agosteo, S; Endo, A; Ferrarini, M; Rakhno, I; Rollet, S; Satoh, D; Vincke, H

2014-01-01

Bonner Spheres Spectrometry in its high-energy extended version is an established method to quantify neutrons at a wide energy range from several meV up to more than 1 GeV. In order to allow for quantitative measurements, the responses of the various spheres used in a Bonner Sphere Spectrometer (BSS) are usually simulated by Monte Carlo (MC) codes over the neutron energy range of interest. Because above 20 MeV experimental cross section data are scarce, intra-nuclear cascade (INC) and evaporation models are applied in these MC codes. It was suspected that this lack of data above 20 MeV may translate to differences in simulated BSS response functions depending on the MC code and nuclear models used, which in turn may add to the uncertainty involved in Bonner Sphere Spectrometry, in particular for neutron energies above 20 MeV. In order to investigate this issue in a systematic way, EURADOS (European Radiation Dosimetry Group) initiated an exercise where six groups having experience in neutron transport calcula...

Fusion with projectiles form carbon to argon at energies between 20A and 60A MeV

International Nuclear Information System (INIS)

Galin, J.

1986-03-01

A review of the linear momentum transfer is made, considering essentially heavy targets and two important parameters in the entrance channel: the projectile energy and its mass. Over a broad mass range, and for energies up to 30A MeV, the momentum transfer scales with the mass of the projectile. At 30A MeV, the most probable value of projectile momentum transferred to the fused system is 80%, and this represents roughly 180 MEV/c per projectile nucleon. At higher bombarding energies, the momentum distribution in the fused systems, as observed from binary fission events, seems to depend on the mass of the projectile. Further studies are still needed to understand this behaviour. Finally, the decay of highly excited (E* approximately 500-800 MeV) fused systems, with masses close to 270 amu, is studied from the characteristics of both fusion fragments and light charged particles. It is shown that thermal equilibrium is reached before fission, even for such high energy deposition. However, the decay sequence is sensitive to dynamical effects and does not depend only on available phase space

Integral measurement of the {sup 12}C(n, p){sup 12}B reaction up to 10 GeV

Energy Technology Data Exchange (ETDEWEB)

Zugec, P.; Bosnar, D. [University of Zagreb, Department of Physics, Faculty of Science, Zagreb (Croatia); Colonna, N.; Barbagallo, M.; Mastromarco, M.; Tagliente, G.; Variale, V. [Istituto Nazionale di Fisica Nucleare, Bari (Italy); Ventura, A. [Istituto Nazionale di Fisica Nucleare, Bologna (Italy); Mengoni, A. [ENEA, Bologna (Italy); Altstadt, S.; Langer, C.; Lederer, C.; Reifarth, R.; Schmidt, S.; Weigand, M. [Johann-Wolfgang-Goethe Universitaet, Frankfurt (Germany); Andrzejewski, J.; Marganiec, J.; Perkowski, J. [Uniwersytet Lodzki, Lodz (Poland); Audouin, L.; Leong, L.S.; Tassan-Got, L. [Centre National de la Recherche Scientifique/IN2P3 - IPN, Orsay (France); Becares, V.; Cano-Ott, D.; Garcia, A.R.; Gonzalez-Romero, E.; Martinez, T.; Mendoza, E. [Centro de Investigaciones Energeticas Medioambientales y Tecnologicas (CIEMAT), Madrid (Spain); Becvar, F.; Krticka, M.; Kroll, J.; Valenta, S. [Charles University, Prague (Czech Republic); Belloni, F.; Mondalaers, W.; Plompen, A.; Schillebeeckx, P. [European Commission JRC, Institute for Reference Materials and Measurements, Geel (Belgium); Berthoumieux, E.; Fraval, K.; Gunsing, F. [CEA/Saclay - IRFU, Gif-sur-Yvette (France); Billowes, J.; Ware, T.; Wright, T. [University of Manchester, Manchester (United Kingdom); Boccone, V.; Brugger, M.; Calviani, M.; Cerutti, F.; Chiaveri, E.; Chin, M.; Ferrari, A.; Guerrero, C.; Losito, R.; Roman, F.; Rubbia, C.; Tsinganis, A.; Versaci, R.; Vlachoudis, V.; Weiss, C. [CERN, Geneva (Switzerland); Calvino, F.; Cortes, G.; Gomez-Hornillos, M.B.; Riego, A. [Universitat Politecnica de Catalunya, Barcelona (Spain); Carrapico, C.; Goncalves, I.F.; Sarmento, R.; Vaz, P. [Universidade de Lisboa, C2TN-Instituto Superior Tecnico, Lisboa (Portugal); Cortes-Giraldo, M.A.; Praena, J.; Quesada, J. [Universidad de Sevilla, Sevilla (Spain); Cosentino, L.; Finocchiaro, P. [INFN - Laboratori Nazionali del Sud, Catania (Italy); Diakaki, M.; Karadimos, D.; Kokkoris, M.; Vlastou, R. [National Technical University of Athens (NTUA), Athens (Greece); Domingo-Pardo, C.; Giubrone, G.; Tain, J.L. [CSIC-Universidad de Valencia, Instituto de Fisica Corpuscular, Valencia (Spain); Dressler, R.; Heinitz, S.; Kivel, N.; Schumann, D. [Paul Scherrer Institut, Villigen (Switzerland); Duran, I.; Tarrio, D. [Universidade de Santiago de Compostela, Santiago de Compostela (Spain); Eleftheriadis, C.; Manousos, A. [Aristotle University of Thessaloniki, Thessaloniki (Greece); Ganesan, S.; Gurusamy, P.; Saxena, A. [Bhabha Atomic Research Centre (BARC), Mumbai (India); Griesmayer, E.; Jericha, E.; Leeb, H. [Atominstitut der Oesterreichischen Universitaeten, Technische Universitaet Wien, Wien (Austria); Jenkins, D.G.; Vermeulen, M.J. [University of York, York, Heslington (United Kingdom); Kaeppeler, F. [Karlsruhe Institute of Technology (KIT), Institut fuer Kernphysik, Karlsruhe (Germany); Lo Meo, S. [Istituto Nazionale di Fisica Nucleare, Bologna (Italy); ENEA, Bologna (Italy); Massimi, C.; Mingrone, F.; Vannini, G. [Dipartimento di Fisica, Universita di Bologna (IT); INFN, Bologna (IT); Mastinu, P. [Laboratori Nazionali di Legnaro, Istituto Nazionale di Fisica Nucleare, Legnaro (IT); Milazzo, P.M. [Istituto Nazionale di Fisica Nucleare, Trieste (IT); Mirea, M. [Horia Hulubei National Institute of Physics and Nuclear Engineering - IFIN HH, Magurele (RO); Musumarra, A. [Universita di Catania, Dipartimento di Fisica e Astronomia DFA, Catania (IT); INFN-Laboratori Nazionali del Sud, Catania (IT); Paradela, C. [European Commission JRC, Institute for Reference Materials and Measurements, Geel (BE); Universidade de Santiago de Compostela, Santiago de Compostela (ES); Pavlik, A. [Faculty of Physics, University of Vienna, Wien (AT); Rauscher, T. [University of Hertfordshire, Centre for Astrophysics Research, School of Physics, Astronomy and Mathematics, Hatfield (GB); University of Basel, Department of Physics, Basel (CH); Wallner, A. [Faculty of Physics, University of Vienna, Wien (AT); Australian National University, Research School of Physics and Engineering, Canberra (AU)

2016-04-15

The integral measurement of the {sup 12}C(n, p){sup 12}B reaction was performed at the neutron time-of-flight facility nTOF at CERN. The total number of {sup 12}B nuclei produced per neutron pulse of the nTOF beam was determined using the activation technique in combination with a time-of-flight technique. The cross section is integrated over the nTOF neutron energy spectrum from reaction threshold at 13.6 MeV to 10 GeV. Having been measured up to 1GeV on basis of the {sup 235}U(n, f) reaction, the neutron energy spectrum above 200 MeV has been re-evaluated due to the recent extension of the cross section reference for this particular reaction, which is otherwise considered a standard up to 200 MeV. The results from the dedicated GEANT4 simulations have been used to evaluate the neutron flux from 1 GeV up to 10 GeV. The experimental results related to the {sup 12}C(n, p){sup 12}B reaction are compared with the evaluated cross sections from major libraries and with the predictions of different GEANT4 models, which mostly underestimate the {sup 12}B production. On the contrary, a good reproduction of the integral cross section derived from measurements is obtained with TALYS-1.6 calculations, with optimized parameters. (orig.)

Analysis of the AGS experiment on a mercury target with a moderator and a lead reflector bombarded by GeV energy protons

International Nuclear Information System (INIS)

Maekawa, Fujio; Meigo, Shin-ichiro; Kasugai, Yoshimi; Takada, Hiroshi; Ikeda, Yujiro; Ino, Takashi; Sato, Setsuo

2001-01-01

The AGS experiment on a mercury target with a moderator and a lead reflector bombarded by GeV energy protons was analyzed to investigate prediction capability of Monte Carlo simulation codes used in neutronic designs of spallation neutron sources. The NMTC/JAM code was used for nucleon meson transport calculations above 20 MeV while the MCNP-4A code with the JENDL cross section library was used for neutron transport below 20 MeV. The MCNPX code with the LA-150 library was also used for a reference. The calculations were compared with the experimental data obtained with 1.94, 12 and 24 GeV proton beams: (1) neutron flux distributions along the mercury target and (2) spectral fluxes of thermal neutrons extracted from a light water moderator. As a result, it was found that all the calculations predicted these experimental results with accuracies better than ±50% in absolute values. Accordingly, it was concluded that these calculation codes were adequate for neutronics designs of spallation neutron sources. (author)

Measurement of the neutron-induced fission cross section of 232Th relative to 235U from 0.7 to 30 MeV

International Nuclear Information System (INIS)

Behzens, T.W.; Ables, E.; Browne, T.C.

1982-01-01

The authors have measured the fission cross-section ratio 232 Th: 235 U as a function of neutron energy from 0.7 to 30 MeV using ionization fission chambers, the threshold cross-section method, and the time-of-flight technique at the Lawrence Livermore National Laboratory 100-MeV electron linear accelerator. The measured cross-section ratio, averaged over the neutron energy interval from 1.75 to 4.00 MeV, was 0.1086 + 0.0024

A comparative study of 30MeV boron4+ and 60MeV oxygen8+ ion irradiated Si NPN BJTs

International Nuclear Information System (INIS)

Kumar, M. Vinay; Krishnaveni, S.; Yashoda, T.; Dinesh, C. M.; Krishnakumar, K. S.; Jayashree, B.; Ramani

2015-01-01

The impact of 30MeV boron 4+ and 60MeV oxygen 8+ ion irradiation on electrical characteristics of 2N3773 Si NPN Bipolar junction transistors (BJTs) is reported in the present study. The transistors were decapped and irradiated at room temperature. Gummel characteristics, DC current gain and Capacitance-voltage (C-V) characteristics were studied before and after irradiation at different fluences. DC current gain has decreased significantly in both boron and oxygen ion irradiation. Also the value of capacitance decreased 3-4 times with increase in fluence. Both 30MeV boron ion and 60MeV oxygen ion induced similar extent of degradation in electrical characteristics of the transistor

Experimental and theoretical study of radionuclide production on the electronuclear plant target and construction materials irradiated by 1.5 GeV and 130 MeV protons

International Nuclear Information System (INIS)

Titarenko, Yu.E.; Karpikhin, E.I.; Smolyakov, A.F.; Igumnov, M.M.; Stepanov, N.V.; Kazaritsky, V.D.; Batyaev, V.F.; Shvedov, O.V.; Mashnik, S.G.; Gabriel, T.A.

1997-01-01

Experimental and calculated results are presented for the yields of residual nuclei in 63 Cu, 65 Cu, 206 Pb, 207 Pb, 208 Pb, and 209 Bi targets irradiated to 1.5 GeV and 130 MeV protons and in 59 Co target irradiated to 1.2 GeV protons extracted from the ITEP accelerator. The nuclide yields were found by gamma-spectrometry with a GC-2518 Ge detector, a 1510 module, and a S-100 plate that, as an integral part of IBM PC, emulates a multichannel analyzer. The gamma-spectrometry 60 Co 1332.5 keV line energy resolution was 1.8 keV. The gamma-spectra were processed by the ASPRO code. The SIGMA code with the GDISP radionuclide database was used to identify the gamma-lines and to calculate the respective cross sections. The monitor reactions was 27 Al(p,3pn) 24 Na. The experimental generation cross sections of end products are compared with the respective values calculated by the HETC, INUCL, and CEM95 codes that simulate hadron-nucleus interactions. 12 refs., 3 figs., 7 tabs

Contribution to π+p inelastic scattering at incoming pion energies near 1 GeV

International Nuclear Information System (INIS)

Deler, B.

1969-01-01

Results on π + p scattering at 810 and 1300 MeV incoming kinetic energy are presented. In the three-body final states (π + p → π + π 0 p or π + π + n) the N * 33 production is strongly dominant. At 1300 MeV one also observes the ρ, N * 1/2 3/2 and N * 1/2 5/2 productions. The difficulty in correctly separating these channels demands trying a more general analysis, taking simultaneously into account several processes (N * π, ρN,...). A generalized isobaric model is discussed. Assuming the interaction of particles by pairs, we can carry out a partial wave analysis of the three body final state reactions. The expansion of the differential cross section in spherical harmonics for data between 600 and 1460 MeV (compilation of data from different laboratories) leads to a simple discussion of the angular effects for different parts of the Dalitz plot. A partial wave analysis has been made below 1 GeV. The reaction p π + π 0 is correctly explained by considering only the N * 33 production. The different partial waves are in agreement with the elastic phase shift analysis, except for the wave SD1 (corresponding to the elastic wave S31) which is found to be small. Therefore, the S31 resonance appears weakly coupled to the N * 33 -π channel. (author) [fr

LEAP [Low-Energy Antiproton]: A balloon-borne search for low-energy cosmic-ray antiprotons

International Nuclear Information System (INIS)

Moats, A.R.M.

1989-01-01

The LEAP (Low-Energy Antiproton) experiment is a search for cosmic-ray antiprotons in the 120 MeV to 1.2 GeV kinetic energy range. The motivation for this project was the result announced by Buffington et. al. (1981) that indicated an anomalously high antiproton flux below 300 MeV; this result has compelled theorists to propose sources of primary antiprotons above the small secondary antiproton flux produced by high energy cosmic-ray collisions with nuclei in the interstellar medium. LEAP consisted of the NMSU magnetic spectrometer, a time-of-flight system designed at Goddard Space Flight Center, two scintillation detectors, and a Cherenkov counter designed and built at the University of Arizona. Analysis of flight data performed by the high-energy astrophysics group at Goddard Space Flight Center revealed no antiproton candidates found in the 120 MeV to 360 MeV range; 3 possible antiproton candidate events were found in the 500 MeV to 1.2 GeV range in an analysis done here at the University of Arizona. However, since it will be necessary to sharpen the calibration on all of the LEAP systems in order to positively identify these events as antiprotons, only an upper limit has been determined at present. Thus, combining the analyses performed at the University of Arizona and Goddard Space Flight Center, 90% confidence upper limits of 3.5 x 10 -5 in the 120 MeV to 360 MeV range and 2.3 x 10 -4 in the 500 MeV to 1.2 GeV range for the antiproton/proton ratio is indicated by the LEAP results. LEAP disagrees sharply with the results of the Buffington group, indicating a low antiproton flux at these energies

Slow running of the Gradient Flow coupling from 200 MeV to 4 GeV in $N_{\\rm f}=3$ QCD

CERN Document Server

Dalla Brida, Mattia; Korzec, Tomasz; Ramos, Alberto; Sint, Stefan; Sommer, Rainer

2017-01-25

Using a finite volume Gradient Flow (GF) renormalization scheme with Schr\\"odinger Functional (SF) boundary conditions, we compute the non-perturbative running coupling in the range $2.2 \\lesssim {\\bar g}_\\mathrm{GF}^2(L) \\lesssim 13$. Careful continuum extrapolations turn out to be crucial to reach our high accuracy. The running of the coupling is always between one-loop and two-loop and very close to one-loop in the region of $200\\,{\\rm MeV} \\lesssim \\mu=1/L \\lesssim 4\\,{\\rm GeV}$. While there is no convincing contact to two-loop running, we match non-perturbatively to the SF coupling with background field. In this case we know the $\\mu$ dependence up to $\\sim 100\\,{\\rm GeV}$ and can thus connect to the $\\Lambda$-parameter.

Measurement of excitation yields of low energy prompt γ-ray from proton bombardment of Cr-foils with energies ranging between 1.0 and 3.0 MeV

International Nuclear Information System (INIS)

Goncharov, A.

2014-01-01

The goal of this work is measurement of differential cross sections for the production of 378 keV γ-rays from the reactions 52 Cr(p,γ1) 53 Mn and 53 Cr(p,nγ1) 53 Mn for proton energies ranging between 1.0 and 3.0 MeV at the laboratory angle of 90° using foils with thickness ∼1.9×10 18 at/cm 2 (∼ 0.23 μm) of nat Cr.

1-GeV Linac Upgrade Study at Fermilab

International Nuclear Information System (INIS)

Popovic, M.; Moretti, A.; Noble, R.; Schmidt, C.W.

1998-09-01

A linac injector for a new proton source complex at Fermilab is assumed to have a kinetic energy of 1 GeV. This linac would be sized to accelerate 100 mA of H - beam in a 200 microsecond pulse at a 15 Hz repetition rate. This would be adequate to produce ∼10 14 protons per pulse allowing for future improvements of the new proton source complex. An alternate proposal is to add 600 MeV of side coupled cavity linac at 805 MHz to the existing 400 MeV Linac. This addition may either be in a new location or use the present Booster tunnel. A discussion of these possibilities will be given

The 56Fe(n,x α) reaction from threshold to 30 MeV

International Nuclear Information System (INIS)

Sterbenz, S.M.; Young, P.G.; Bateman, F.B.

1994-01-01

Alpha-particle emission in neutron reactions with 56 Fe has been studied from threshold to over 30 MeV using the spallation neutron source at WNR/LAMPF. Alpha-particle production cross sections, spectra, and angular distributions were measured at scattering angles of 30, 60, 90, and 135 degrees using detector telescopes consisting of a low-pressure gas proportional counter and a large area silicon detector. Time-of-flight techniques with a 10-meter flight path were used to deduce the incident neutron energies. Our results are compared with literature values and with several theoretical calculations

Non-equilibrium processes in p + Ag collisions at GeV energies

Science.gov (United States)

Fidelus, M.; Filges, D.; Goldenbaum, F.; Jarczyk, L.; Kamys, B.; Kistryn, M.; Kistryn, St.; Kozik, E.; Kulessa, P.; Machner, H.; Magiera, A.; Piskor-Ignatowicz, B.; Pysz, K.; Rudy, Z.; Sharma, Sushil K.; Siudak, R.; Wojciechowski, M.; PISA Collaboration

2017-12-01

The double differential spectra d2σ /d Ω d E of p , d , t , 3,4,6He, 6,7,8,9Li, 7,9,10Be, and 10,11,12B were measured at seven scattering angles, 15.6∘, 20∘, 35∘, 50∘, 65∘, 80∘, and 100∘, in the laboratory system for proton induced reactions on a silver target. Measurements were done for three proton energies: 1.2, 1.9, and 2.5 GeV. The experimental data were compared to calculations performed by means of two-step theoretical microscopic models. The first step of the reaction was described by the intranuclear cascade model incl4.6 and the second one by four different models (ABLA07, GEM2, gemini++, and SMM) using their standard parameter settings. Systematic deviations of the data from predictions of the models were observed. The deviations were especially large for the forward scattering angles and for the kinetic energy of emitted particles in the range from about 50 to 150 MeV. This suggests that some important non-equilibrium mechanism is lacking in the present day microscopic models of proton-nucleus collisions in the studied beam energy range.

NSRL 200 MeV linac beam energy stabilization system

International Nuclear Information System (INIS)

Huang Guirong; Pei Yuanji; Dong Sai

2001-01-01

By using the computer image processing technology and RF phase auto-shifting system, the ESS (Energy Stabilization System) was applied to 200 MeV Linac. the ESS adjusts beam energy automatically in a range of +-4 MeV. After adjustment beam energy stability is improved to +-6%

/sup 12/C(γ,n) cross section from 30 to 100 MeV

International Nuclear Information System (INIS)

Harty, P.D.; Thompson, M.N.; O'Keefe, G.J.

1988-01-01

This paper reports a measurement of the differential photoneutron cross section of /sup 12/C at 65 0 , between E/sub γ/ = 30 and 100 MeV. Tagged photons, monochromatic to within 2.6 MeV, were used, thus allowing the cross sections to a wide range of final states to be observed. The results are compared to the photoproton cross section of /sup 12/C, which was measured previously, under similar conditions. Comparisons are also made with calculations based on the quasi-deuteron model, and with calculations by Gari and Hebach, and Cavinato et al. These latter calculations incorporate two-body effects by the inclusion of meson exchange currents. The agreement between these calculations and the measured cross section is in contrast to predictions of a direct, single-nucleon knockout model of the reaction mechanism, indicating the importance of two-body effects in the photoreaction process for energies greater than 50 MeV

Some energy and angular characteristics of electrons in electromagnetic cascades in air

Science.gov (United States)

Stanev, T.; Vankov, Kh.; Petrov, S.; Elbert, J. W.

The angular distribution of electrons with threshold energies of 20 MeV (the lowest energy at which electrons radiate Cerenkov photons in the air) are considered. The results are based on Monte Carlo calculations of the development of electromagnetic cascades. A set of showers with energy thresholds equals 20 MeV and primary photon energies equals 10, 20, 30, and 100 GeV is simulated. Information about the particle properties (energy, angle, and radial displacement) is provided at each radiation length of depth. The electrons are at much smaller angles to the shower axis than were those of Messel and Crawford (1970); this explains the discrepancy in angular distribution of Cerenkov light in air between the two.

Investigation of the p+N → [Σ0K+]+N reaction at the proton energy Ep = 70 GeV

International Nuclear Information System (INIS)

Anon.

1994-01-01

The p+N → [Σ 0 K + ]+N reaction was studied in experiments using the SPHINX detector placed in the 70-GeV proton beam of the IHEP accelerator. In the effective mass spectrum of the M(Σ 0 K + ) system produced in the coherent diffractive transition, a clear peak with mass M = 1999 ± 7 MeV and width Γ = 91 ± 17 MeV was observed in addition to the near-threshold structure with mass M ≅ 1800 MeV. 7 refs., 3 figs

Studies of Hadronic Event Structure in $e^+ e^-$ Annihilation from 30 GeV to 209 GeV with the L3 Detector

CERN Document Server

Achard, P.; Aguilar-Benitez, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M.G.; Anderhub, H.; Andreev, Valery 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.; Barillere, 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.; Bohm, 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.; Romeo, G.Cara; Carlino, G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Chamizo, 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.; de la Cruz, B.; Cucciarelli, S.; van Dalen, J.A.; de Asmundis, R.; Deglon, P.; Debreczeni, J.; Degre, A.; Dehmelt, K.; Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; Dionisi, C.; Dittmar, M.; Doria, A.; Dova, M.T.; Duchesneau, D.; Duda, M.; Echenard, B.; Eline, A.; El Hage, A.; El Mamouni, H.; Engler, A.; Eppling, F.J.; Extermann, P.; Falagan, 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.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Iouri; Ganguli, S.N.; Garcia-Abia, Pablo; Gataullin, M.; Gentile, S.; Giagu, S.; Gong, Z.F.; Grenier, Gerald Jean; Grimm, O.; Gruenewald, M.W.; Guida, M.; Gupta, V.K.; Gurtu, A.; Gutay, L.J.; Haas, D.; Hatzifotiadou, D.; Hebbeker, T.; Herve, Alain; Hirschfelder, J.; Hofer, H.; Hohlmann, M.; Holzner, G.; Hou, S.R.; Hu, Y.; Jin, B.N.; Jones, Lawrence W.; de Jong, P.; Josa-Mutuberria, I.; Kaur, M.; Kienzle-Focacci, M.N.; Kim, J.K.; Kirkby, Jasper; Kittel, W.; Klimentov, A.; Konig, A.C.; Kopal, M.; Koutsenko, V.; Kraber, M.; Kraemer, R.W.; Kruger, A.; Kunin, A.; Ladron 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.; Levtchenko, P.; Li, C.; Likhoded, S.; Lin, C.H.; Lin, W.T.; Linde, F.L.; Lista, L.; Liu, Z.A.; Lohmann, W.; Longo, E.; Lu, Y.S.; Luci, C.; Luminari, L.; Lustermann, W.; Ma, W.G.; Malgeri, L.; Malinin, A.; Mana, C.; Mangeol, D.; 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.; Musicar, B.; Musy, M.; Nagy, S.; Natale, S.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Novak, T.; Kluge, Hannelies; Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares, C.; Paolucci, P.; Paramatti, R.; Passaleva, G.; Patricelli, S.; Paul, Thomas Cantzon; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Petersen, B.; Piccolo, D.; Pierella, F.; Pioppi, M.; Piroue, P.A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofev, D.; Quartieri, J.; Rahal-Callot, G.; Rahaman, Mohammad Azizur; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P.G.; Ranieri, R.; Raspereza, A.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Riemann, S.; Riles, Keith; Roe, B.P.; Romero, L.; Rosca, A.; Rosemann, C.; Rosenbleck, C.; Rosier-Lees, S.; Roth, Stefan; Rubio, J.A.; Ruggiero, G.; Rykaczewski, H.; Sakharov, A.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Schafer, C.; Schegelsky, V.; Schopper, H.; 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.; Straessner, A.; Sudhakar, K.; Sultanov, G.; Sun, L.Z.; Sushkov, S.; Suter, H.; Swain, J.D.; Szillasi, Z.; Tang, X.W.; Tarjan, P.; Tauscher, L.; Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, Charles; Ting, Samuel C.C.; Ting, S.M.; Tonwar, S.C.; Toth, J.; Tully, C.; Tung, K.L.; Ulbricht, J.; Valente, E.; Van de Walle, R.T.; Vasquez, R.; Veszpremi, V.; Vesztergombi, G.; Vetlitsky, I.; Vicinanza, D.; Viertel, G.; Villa, S.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobev, I.; Vorobyov, A.A.; Wadhwa, M.; Wang, Q.; Wang, X.L.; Wang, Z.M.; Weber, M.; Wilkens, H.; Wynhoff, S.; Xia, L.; Xu, Z.Z.; Yamamoto, J.; Yang, B.Z.; Yang, C.G.; Yang, H.J.; Yang, M.; Yeh, S.C.; Zalite, An.; Zalite, Yu.; Zhang, Z.P.; Zhao, J.; Zhu, G.Y.; Zhu, R.Y.; Zhuang, H.L.; Zichichi, A.; Zimmermann, B.; Zoller, M.

2004-01-01

In this Report, QCD results obtained from a study of hadronic event structure in high energy e^+e^- interactions with the L3 detector are presented. The operation of the LEP collider at many different collision energies from 91 GeV to 209 GeV offers a unique opportunity to test QCD by measuring the energy dependence of different observables. The main results concern the measurement of the strong coupling constant, \\alpha_s, from hadronic event shapes and the study of effects of soft gluon coherence through charged particle multiplicity and momentum distributions.

Parity violation experiments at intermediate energies

International Nuclear Information System (INIS)

Van Oers, W.T.H.

1996-06-01

The status of the TRIUMF 221 MeV proton-proton violation experiment is reviewed. Several other proton-proton parity violation experiments in the in the intermediate energy range, currently in various stages of preparation, are discussed. A new experiment at an energy of 5.13 GeV (and if confirmed also at an energy of tens of GeV) is needed to follow on the earlier unexpected large result obtained at 5.13 GeV. (author)

A high intensity beam line of γ-rays up to 22MeV energy based on Compton backscattering

International Nuclear Information System (INIS)

Guo, W.; Xu, W.; Chen, J.G.; Ma, Y.G.; Cai, X.Z.; Wang, H.W.; Xu, Y.; Wang, C.B.; Lu, G.C.; Tian, W.D.; Yuan, R.Y.; Xu, J.Q.; Wei, Z.Y.; Yan, Z.; Shen, W.Q.

2007-01-01

Shanghai Laser Electron Gamma Source, a high intensity beam line of γ-ray, has been proposed recently. The beam line is expected to generate γ-rays up to the maximum energy of 22MeV by Compton backscattering between a CO 2 laser and electrons in the 3.5 GeV storage ring of the Shanghai Synchrotron Radiation Facility. The flux of non-collimated γ-rays is estimated to be 10 9 -10 10 s -1 when a CO 2 laser of several hundred Watt power is employed. We will discuss physics issues in the design and optimization of the beam line

Correlations of light particles in the reaction 40Ar on 197Au at E/A=200 MeV

International Nuclear Information System (INIS)

Kunde, G.J.

1990-08-01

For the study of small-angle correlations of light particles an experiment at the SATURNE synchrotron with 40 Ar on 197 Au at an incident energy of E/A=200 MeV was performed. A hodoscope consisting of an 8x8 matrix of silicon-cesium iodide detectors was applied under a mean angle of 40 degrees. The evaluation of the coincident particle information was performed via correlation functions, which were determined for systems with Z ≤ = 3. For three different fragments emission temperatures were measured via the determination of population ratios for particle-unstable states. Furthermore by means of p-p correlations the reaction volume was studied. The results are: For 5 Li a mean emission temperature of 6.4 -1.0 1.1 MeV resulted, for 4 He a mean emission temperature of 5.4 -1.2 +1.8 MeV was found. The temperature of 2.3 -0.2 0.6 MeV determined for 8 Be is strongly influenced by feeding. For the states at 21.1 and 22.1 MeV in 4 He a dependence of the temperature on the kinetic sum energy of the coincident particles was found, a temperature growth with increasing sum energy of about 3 MeV over the measured range of the sum energies resulted. Via p-p correlations a source radius of 5.8 ± 0.3 fm was determined. The correction for protons from sequential decays leads to radii, which are about 1 fm smaller. The radii and radius ratios for different ranges of the sum energy of the protons were analyzed. The measured emission temperatures are about 1 MeV higher than the values for the same system at E/A = 60 MeV. The temperatures correspond in the model of the statistical multifragmentation to an excitation energy of about 2 GeV, while they follow in the model of the sequential fragment emission for an excitation energy of about 1 GeV. (orig.) [de

Neutron cross section evaluations of europium isotopes in 1 keV - 30 MeV energy range. Format - validation - comparison; Evaluation de sections efficaces pour des neutrons incidents sur des isotopes d'europium aux energies 1 keV - 30 MeV. Format - validation - comparaison

Energy Technology Data Exchange (ETDEWEB)

Dossantos-Uzarralde, P.; Le Luel, C.; Bauge, E. [CEA Bruyeres le Chatel, 91 (France). Dept. de Physique Theorique et Appliquee

2004-07-01

This paper presents neutron cross section evaluations of Europium isotopes. The cross sections are evaluated in 1 keV - 30 MeV energy range for the isotopes {sup 146}Eu, {sup 147}Eu, {sup 148}Eu, {sup 149}Eu, {sup 150}Eu, {sup 151}Eu, {sup 152}Eu, {sup 153}Eu, {sup 154}Eu in their ground state. This evaluation includes cross section productions of the long life isomeric states. Special attention is put on the options used for the description of the files written in ENDF-6 format. The final issue is a proposal of a new breed of ENDF-6 formatted neutron activation file. (authors)

anti pp and pp elastic scattering from 10 GeV to 1000 GeV centre-of-mass energy

Energy Technology Data Exchange (ETDEWEB)

Islam, M.M. (Connecticut Univ., Storrs (USA). Dept. of Physics); Fearnley, T. (University Coll., London (UK). Dept. of Physics and Astronomy); Guillaud, J.P. (Grenoble-1 Univ., 74 - Annecy (France). Lab. de Physique des Particules)

1984-06-21

Antiproton-proton and proton-proton elastic scattering are studied simultaneously over the energy range ..sqrt..anti s approx.= (10/1000) GeV in a nucleon valence core model proposed earlier. The scattering is described as primarily due to two processes: diffraction and hard scattering. The latter originates from the scattering of a nucleon core off another core. Destructive interference between the two processes produces dips in anti pp and pp differential cross-sections. As energy increases beyond the ISR range (..sqrt..anti s = (23/62) GeV), the dips get filled up, and eventually transform into shoulders or breaks at collider energies. Differences between anti pp and pp differential cross-sections persist even at collider energies. Comparison with ISR data shows that the model provides a quantitative description of pp elastic scattering in this energy range. Predictions of anti pp and pp differential cross-sections at future collider energies ..sqrt..s = 800 and 2000 GeV are given. In order to distinguish between competing models, need for measuring the anti pp differential cross-section at the ISR and SPS collider in the vertical stroketvertical stroke-range (0.5/2.0) (GeV)/sup 2/ is stressed.

P-barp and pp elastic scattering from 10 GeV to 1000 GeV centre-of-mass energy

Energy Technology Data Exchange (ETDEWEB)

Islam, M.M. (Connecticut Univ., Storrs (USA). Dept. of Physics); Fearnley, T. (University Coll., London (UK). Dept. of Physics and Astronomy); Guillaud, J.P. (L.A.P.P. - BP909, 74019 Annecy-Le-Vieux Cedex, France)

1984-06-21

Antiproton-proton and proton-proton elastic scattering are studied simultaneously over the energy range ..sqrt..s approx. (10-1000) GeV in a nucleon valence core model proposed earlier. The scattering is described as primarily due to two processes: diffraction and hard scattering. The latter originates from the scattering of a nucleon core off another core. Destructive interference between the two processes produces dips in p-barp and pp differential cross-sections. As energy increases beyond the ISR range (..sqrt..s = (23-62) GeV), the dips get filled up, and eventually transform into shoulders or breaks at collider energies. Differences between p-barp and pp differential cross-sections persist even at collider energies. Comparison with ISR data shows that the model provides a quantitative description of pp elastic scattering in this energy range. Predictions of p-barp and pp differential cross-sections at future collider energies ..sqrt..s = 800 and 2000 GeV are given. In order to distinguish between competing models, need for measuring the p-barp differential cross-section at the ISR and SPS collider in the abs (t)-range (0.5-2.0) (GeV)/sup 2/ is stressed.

Elastic scattering of deuterons from hydrogen at 2.0, 1.6 and 1.2 GeV, and search for critical opalescence in inelastic scattering of proton from carbon-12 at 800 MeV

International Nuclear Information System (INIS)

Haji-Saeid, S.M.

1980-01-01

Large deuteron vector and tensor asymmetries have been measured for the first time at intermediate energies. The polarized deuteron beam whose tensor and vector components were 0.75 and 0.25, respectively, were used at energies of 2.0, 1.6 and 1.2 GeV. The tensor and vector quantities Pyy and Py were extracted from the data obtained within beam polarization normal to the scattering plane, and Pxx was obtained when the polarization was precessed into the scattering plane. Analysis of the data using multiple scattering theory demonstrates the importance of the non-eikonal correction to the Glauber Model and also the sensitivity of the data to double-spin flip components of the NN amplitudes. In another experiment the differential cross section for the 12C(P,P')12C*(15.11 MeV, 1 + T = 1) reaction has been measured at 800 MeV; the range of the angular distribution corresponds to momentum transfers of 0.7 to 2.4 fm -1 (1 to 3.3 mπ). The cross section decreases almost exponentially at large angles; no maximum is observed in the region where nuclear critical opalescence might be expected. The cross sections which measured in parallel to the 15.11 MeV state were for the levels at 11.83 (2 - ), 12.71 (1 + ), 13.35 (2 - ), 16.1 (2 + ) and 16.58 (2 - ) MeV

Neutron yield and induced radioactivity: a study of 235-MeV proton and 3-GeV electron accelerators

International Nuclear Information System (INIS)

Hsu, Yung-Cheng; Lai, Bo-Lun; Sheu, Rong-Jiun

2016-01-01

This study evaluated the magnitude of potential neutron yield and induced radioactivity of two new accelerators in Taiwan: a 235-MeV proton cyclotron for radiation therapy and a 3-GeV electron synchrotron serving as the injector for the Taiwan Photon Source. From a nuclear interaction point of view, neutron production from targets bombarded with high-energy particles is intrinsically related to the resulting target activation. Two multi-particle interaction and transport codes, FLUKA and MCNPX, were used in this study. To ensure prediction quality, much effort was devoted to the associated benchmark calculations. Comparisons of the accelerators' results for three target materials (copper, stainless steel and tissue) are presented. Although the proton-induced neutron yields were higher than those induced by electrons, the maximal neutron production rates of both accelerators were comparable according to their respective beam outputs during typical operation. Activation products in the targets of the two accelerators were unexpectedly similar because the primary reaction channels for proton- and electron-induced activation are (p,pn) and (γ,n), respectively. The resulting residual activities and remnant dose rates as a function of time were examined and discussed. (authors)

Changing the PEP-II Center-of-Mass Energy Down to 10 GeV and up to 11 GeV

International Nuclear Information System (INIS)

Sullivan, M.

2009-01-01

PEP-II, the SLAC, LBNL, LLNL B-Factory was designed and optimized to run at the Upsilon 4S resonance (10.580 GeV with an 8.973 GeV e- beam and a 3.119 GeV e+ beam). The interaction region (IR) used permanent magnet dipoles to bring the beams into a head-on collision. The first focusing element for both beams was also a permanent magnet. The IR geometry, masking, beam orbits and beam pipe apertures were designed for 4S running. Even though PEP-II was optimized for the 4S, we successfully changed the center-of-mass energy (E cm ) down to the Upsilon 2S resonance and completed an E cm scan from the 4S resonance up to 11.2 GeV. The luminosity throughout most of these changes remained near 1 x 10 34 cm -2 s -1 . The E cm was changed by moving the energy of the high-energy beam (HEB). The beam energy differed by more than 20% which produced significantly different running conditions for the RF system. The energy loss per turn changed 2.5 times over this range. We describe how the beam energy was changed and discuss some of the consequences for the beam orbit in the interaction region. We also describe some of the RF issues that arose and how we solved them as the high-current HEB energy changed

Longitudinal phase-space matching between microtrons at 185 MeV

International Nuclear Information System (INIS)

Takeda, H.

1983-01-01

Electrons are accelerated to 185 MeV by a microtron. Then, they are injected into another microtron to boost the net energy up to a few GeV. Between the two microtrons both longitudinal and transverse phase-space matching are required. In this paper, we consider a longitudinal phase-ellipse matching which utilizes triple left-right-left sector dipoles to induce a negative phase-angle shear. This is accomplished because a high-energy particle travels a shorter distance through the dipole system than a low-energy particle

A simple and powerful XY-Type current monitor for 30 MeV IPEN/CNEN-SP cyclotron

Energy Technology Data Exchange (ETDEWEB)

Barcellos, Henrique; Matsuda, Hylton; Sumyia, Luiz Carlos do A.; Junqueira, Fernando de C.; Costa, Osvaldo L. da, E-mail: hbolivei@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2017-11-01

A water-cooled XY-type current monitor was designed and built in the Cyclotrons Laboratory of the Nuclear and Energy Research Institute (IPEN). It is a very simple design and easily adaptable to the cyclotron beam lines. Tests were done demonstrating to be an instrument of great assistance in proton beam position along beam transport line and target port. Nowadays the XY-type current monitor has been widely used in {sup 18}F-FDG routine productions, employing irradiation system which were originally designed for productions on 18 MeV cyclotron accelerator only, however, applying the XY-type current monitor the target port may be exchanged between the 30 MeV and 18 MeV cyclotrons and the observed results are in perfect agreement with expected. (author)

Single and multi-photon events with missing energy in $e^+ e^-$ collisions at 161 GeV < $\\sqrt{s}$ < 172 GeV

CERN Document Server

Acciarri, M; Aguilar-Benítez, M; Ahlen, S P; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alverson, G; Alviggi, M G; Ambrosi, G; Anderhub, H; Andreev, V P; Angelescu, T; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Baksay, L; Banerjee, S; Banerjee, Sw; Banicz, K; Barczyk, A; Barillère, R; Barone, L; Bartalini, P; Baschirotto, A; Basile, M; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Bhattacharya, S; Biasini, M; Biland, A; Bilei, G M; Blaising, J J; Blyth, S C; Bobbink, Gerjan J; Böck, R K; Böhm, A; Boldizsar, L; Borgia, B; Bourilkov, D; Bourquin, Maurice; Braccini, S; Branson, J G; Brigljevic, V; Brock, I C; Buffini, A; Buijs, A; Burger, J D; Burger, W J; Busenitz, J K; Button, A M; Cai, X D; Campanelli, M; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A M; Casaus, J; Castellini, G; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada-Canales, M; Cesaroni, F; Chamizo-Llatas, M; Chang, Y H; Chaturvedi, U K; Chekanov, S V; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chéreau, X J; Chiefari, G; Chien, C Y; Cifarelli, Luisa; Cindolo, F; Civinini, C; Clare, I; Clare, R; Cohn, H O; Coignet, G; Colijn, A P; Colino, N; Commichau, V; Costantini, S; Cotorobai, F; de la Cruz, B; Csilling, Akos; Dai, T S; D'Alessandro, R; De Asmundis, R; Degré, A; Deiters, K; Della Volpe, D; Denes, P; De Notaristefani, F; DiBitonto, Daryl; Diemoz, M; Van Dierendonck, D N; Di Lodovico, F; Dionisi, C; Dittmar, Michael; Dominguez, A; Doria, A; Dova, M T; Duchesneau, D; Duinker, P; Durán, I; Dutta, S; Easo, S; Efremenko, Yu V; El-Mamouni, H; Engler, A; Eppling, F J; Erné, F C; Ernenwein, J P; Extermann, Pierre; Fabre, M; Faccini, R; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, Marta; Fenyi, B; Ferguson, T; Ferroni, F; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, Frank; Fisher, P H; Fisk, I; Forconi, G; Fredj, L; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gau, S S; Gentile, S; Gheordanescu, N; Giagu, S; Goldfarb, S; Goldstein, J; Gong, Z F; Gougas, Andreas; Gratta, Giorgio; Grünewald, M W; Gupta, V K; Gurtu, A; Gutay, L J; Hartmann, B; Hasan, A; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Van Hoek, W C; Hofer, H; Hong, S J; Hoorani, H; Hou, S R; Hu, G; Innocente, Vincenzo; Jenkes, K; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Kasser, A; Khan, R A; Kamrad, D; Kamyshkov, Yu A; Kapustinsky, J S; Karyotakis, Yu; Kaur, M; Kienzle-Focacci, M N; Kim, D; Kim, D H; Kim, J K; Kim, S C; Kim, Y G; Kinnison, W W; Kirkby, A; Kirkby, D; Kirkby, Jasper; Kiss, D; Kittel, E W; Klimentov, A; König, A C; Kopp, A; Korolko, I; Koutsenko, V F; Krämer, R W; Krenz, W; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lapoint, C; Lassila-Perini, K M; Laurikainen, P; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Leiste, R; Leonardi, E; Levchenko, P M; Li Chuan; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lu, W; Lü, Y S; Lübelsmeyer, K; Luci, C; Luckey, D; Luminari, L; Lustermann, W; Ma Wen Gan; Maity, M; Majumder, G; Malgeri, L; Malinin, A; Maña, C; Mangeol, D J J; Mangla, S; Marchesini, P A; Marin, A; Martin, J P; Marzano, F; Massaro, G G G; McNally, D; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Von der Mey, M; Mi, Y; Mihul, A; Van Mil, A J W; Mirabelli, G; Mnich, J; Molnár, P; Monteleoni, B; Moore, R; Morganti, S; Moulik, T; Mount, R; Müller, S; Muheim, F; Muijs, A J M; Nahn, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Niessen, T; Nippe, A; Nisati, A; Nowak, H; Oh, Yu D; Opitz, H; Organtini, G; Ostonen, R; Palomares, C; Pandoulas, D; Paoletti, S; Paolucci, P; Park, H K; Park, I H; Pascale, G; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Peach, D; Pei, Y J; Pensotti, S; Perret-Gallix, D; Petersen, B; Petrak, S; Pevsner, A; Piccolo, D; Pieri, M; Pinto, J C; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Postema, H; Produit, N; Prokofev, D; Prokofiev, D O; Rahal-Callot, G; Raja, N; Rancoita, P G; Rattaggi, M; Raven, G; Razis, P A; Read, K; Ren, D; Rescigno, M; Reucroft, S; Van Rhee, T; Riemann, S; Riles, K; Robohm, A; Rodin, J; Roe, B P; Romero, L; Rosier-Lees, S; Rosselet, P; Van Rossum, W; Roth, S; Rubio, Juan Antonio; Ruschmeier, D; Rykaczewski, H; Salicio, J; Sánchez, E; Sanders, M P; Sarakinos, M E; Sarkar, S; Sassowsky, M; Schäfer, C; Shchegelskii, V; Schmidt-Kärst, S; Schmitz, D; Schmitz, P; Scholz, N; Schopper, Herwig Franz; Schotanus, D J; Schwenke, J; Schwering, G; Sciacca, C; Sciarrino, D; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shukla, J; Shumilov, E; Shvorob, A V; Siedenburg, T; Son, D; Sopczak, André; Smith, B; Spillantini, P; Steuer, M; Stickland, D P; Stone, A; Stone, H; Stoyanov, B; Strässner, A; Strauch, K; Sudhakar, K; Sultanov, G G; Sun, L Z; Susinno, G F; Suter, H; Swain, J D; Tang, X W; Tauscher, Ludwig; Taylor, L; Ting, Samuel C C; Ting, S M; Tonutti, M; Tonwar, S C; Tóth, J; Tully, C; Tuchscherer, H; Tung, K L; Uchida, Y; Ulbricht, J; Uwer, U; Valente, E; Van de Walle, R T; Vesztergombi, G; Vetlitskii, I; Viertel, Gert M; Vivargent, M; Völkert, R; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Vorvolakos, A; Wadhwa, M; Wallraff, W; Wang, J C; Wang, X L; Wang, Z M; Weber, A; Wittgenstein, F; Wu, S X; Wynhoff, S; Xu, J; Xu, Z Z; Yang, B Z; Yang, C G; Yao, X Y; Ye, J B; Yeh, S C; You, J M; Zalite, A; Zalite, Yu; Zemp, P; Zeng, Y; Zhang, Z; Zhang, Z P; Zhou, B; Zhu, G Y; Zhu, R Y; Zichichi, Antonino; Ziegler, F

1997-01-01

A search for single and multi-photon events with missing energy is performed using data collected at centre-of-mass energies between 161 GeV and 172 GeV for a total of 20.9 pb$^{-1}$ of integrated luminosity. The results obtained are used to derive the value for the $\

Photoproduction in the Energy Range 70-200 GeV

CERN Multimedia

2002-01-01

This experiment continues the photoproduction studies of WA4 and WA57 up to the higher energies made available by the upgrading of the West Hall. An electron beam of energy 200 GeV is used to produce tagged photons in the range 65-180 GeV; The photon beam is incident on a 60 cm liquid hydrogen target in the Omega Spectrometer. A Ring Image Cherenkov detector provides pion/kaon separation up to 150 GeV/c. The Transition Radiation Detector extends the charged pion identification to the momentum range from about 80 GeV/c upwards. The large lead/liquid scintillator calorimeter built by the WA70 collaboration and the new lead/scintillating fibre det (Plug) are used for the detection of the $\\gamma$ rays produced by the interactions of the primary photons in the hydrogen target. \\\\ \\\\ The aim is to make a survey of photoproduction reactions up to photon energies of 200 GeV. The large aperture of the Omega Spectrometer will particularly enable study of fragmentation of the photon to states of high mass, up to @C 9 G...

Measurement of neutron-production double-differential cross sections for intermediate energy pion incident reaction

International Nuclear Information System (INIS)

Iwamoto, Yosuke; Shigyo, Nobuhiro; Satoh, Daiki

2002-01-01

Neutron-production double-differential cross sections for 870-MeV π + and π - and 2.1-GeV π + mesons incident on iron and lead targets were measured with NE213 liquid scintillators by time-of-flight technique. NE213 liquid scintillators 12.7 cm in diameter and 12.7 cm thick were placed in directions of 15, 30, 60, 90, 120 and 150deg. The typical flight path length was 15 m. Neutron detection efficiencies were derived from the calculation results of SCINFUL and CECIL codes. The experimental results were compared with the JAM code. The double differential cross sections calculated by the JAM code disagree with experimental data at neutron energies below about 30 MeV. JAM overestimates π + -incident neutron-production cross sections in forward angles at neutron energies of 100 to 500 MeV. (author)

High efficiency charge recuperation for electron beams of MeV energies

International Nuclear Information System (INIS)

MacLachlan, J.A.

1996-05-01

Electron cooling of ion beams with energies of some GeV per nucleon requires high-quality electron beams of MeV energies and currents as high as several amperes. The enormous beam power dictates that the beam current be returned to the high voltage terminal which provides the accelerating potential. The beam is returned to a carefully designed collector within the terminal and biased a few kV positive with respect to it. Thus the load on the HV supply is only the accelerating potential times the sum of the beam current loss and the current used to maintain a graded potential on the accelerating structure. If one employs an electrostatic HV supply like a Van de Graaff with maximum charging current of a few hundred microA, the permissible fractional loss is ∼ 10 -4 . During the 15 years or so the concept of medium energy electron cooling has been evolving, the need to demonstrate the practicability of such high efficiency beam recovery has been recognized. This paper will review some experimental tests and further experiments which have been proposed. The design and status are presented for a new re-circulation experiment at 2 MV being carried out by Fermilab at National Electrostatics Corp

Monte Carlo benchmark calculations of energy deposition by electron/photon showers up to 1 GeV

International Nuclear Information System (INIS)

Mehlhorn, T.A.; Halbleib, J.A.

1983-01-01

Over the past several years the TIGER series of coupled electron/photon Monte Carlo transport codes has been applied to a variety of problems involving nuclear and space radiations, electron accelerators, and radioactive sources. In particular, they have been used at Sandia to simulate the interaction of electron beams, generated by pulsed-power accelerators, with various target materials for weapons effect simulation, and electron beam fusion. These codes are based on the ETRAN system which was developed for an energy range from about 10 keV up to a few tens of MeV. In this paper we will discuss the modifications that were made to the TIGER series of codes in order to extend their applicability to energies of interest to the high energy physics community (up to 1 GeV). We report the results of a series of benchmark calculations of the energy deposition by high energy electron beams in various materials using the modified codes. These results are then compared with the published results of various experimental measurements and other computational models

The elastic scattering of K-mesons on the 4He nucleus in the complex momenta theory for the energy region (20-100) GeV

International Nuclear Information System (INIS)

Grigoryan, L.A.; Shakhbazyan, V.A.

1976-01-01

Determined are differential cross sections for K meson elastic scattering on a 4 He nucleus for the energies of an incident particle equal to 30 and 50 GeV, the total cross section in the range from 10 to 10 3 GeV and the di(GeV/c) 2 versus energy in the range 10-100 GeV. The calculation is carried out with the eikonal and quasieikonal models of the complex moment theory. The effects of inelastic screening are shown to be very essential

J/ψ reconstruction in the di-muon decay channel with the CBM experiment for p+Au collisions at 30 GeV laboratory beam energy

International Nuclear Information System (INIS)

Akishina, V; Kisel, I

2013-01-01

The study of p+Au collisions at 30 GeV laboratory beam energy is considered as a part of the CBM research program and will be performed in the first phase of FAIR with a start version of the CBM detector at SIS-100. Results of J/ψ reconstruction feasibility studies in di-muon channel in proton-nuclear collisions at SIS 100 energies are presented. The simulated detector concept includes STS and MuCh detectors. The study was performed for a wide range of MuCh detector inefficiency. Also the influence of MuCh stations misalignment on the charmonium reconstruction efficiency was studied. The algorithm allows to reconstruct J/ψ with an efficiency of 31.3 % and the signal to the background ratio of 24.4.

Measurement of 1.7–74 MeV polarised γ rays with the HARPO TPC

Energy Technology Data Exchange (ETDEWEB)

Geerebaert, Y., E-mail: yannick.geerebaert@polytechnique.fr [LLR, École Polytechnique, CNRS/IN2P3, Palaiseau (France); Gros, Ph., E-mail: philippe.gros@llr.in2p3.fr [LLR, École Polytechnique, CNRS/IN2P3, Palaiseau (France); Amano, S. [LASTI, University of Hyôgo (Japan); Attié, D. [CEA, Irfu, CEA-Saclay (France); Bernard, D.; Bruel, P. [LLR, École Polytechnique, CNRS/IN2P3, Palaiseau (France); Calvet, D.; Colas, P. [CEA, Irfu, CEA-Saclay (France); Daté, S. [JASRI/SPring8 (Japan); Delbart, A. [CEA, Irfu, CEA-Saclay (France); Frotin, M.; Giebels, B. [LLR, École Polytechnique, CNRS/IN2P3, Palaiseau (France); Götz, D. [AIM, CEA/DSM-CNRS – Université Paris Diderot (France); IRFU/Service d' Astrophysique, CEA-Saclay (France); Hashimoto, S. [LASTI, University of Hyôgo (Japan); Horan, D. [LLR, École Polytechnique, CNRS/IN2P3, Palaiseau (France); Kotaka, T. [LASTI, University of Hyôgo (Japan); Louzir, M. [LLR, École Polytechnique, CNRS/IN2P3, Palaiseau (France); Minamiyama, Y.; Miyamoto, S. [LASTI, University of Hyôgo (Japan); Ohkuma, H. [JASRI/SPring8 (Japan); and others

2017-02-11

Current γ-ray telescopes based on photon conversions to electron-positron pairs, such as Fermi, use tungsten converters. They suffer of limited angular resolution at low energies, and their sensitivity drops below 1 GeV. The low multiple scattering in a gaseous detector gives access to higher angular resolution in the MeV–GeV range, and to the linear polarisation of the photons through the azimuthal angle of the electron-positron pair. HARPO is an R&D programme to characterise the operation of a TPC (Time Projection Chamber) as a high angular-resolution and sensitivity telescope and polarimeter for γ rays from cosmic sources. It represents a first step towards a future space instrument. A 30 cm cubic TPC demonstrator was built, and filled with 2 bar argon-based gas. It was put in a polarised γ-ray beam at the NewSUBARU accelerator in Japan in November 2014. Data were taken at different photon energies from 1.7 MeV to 74 MeV, and with different polarisation configurations. The electronics setup is described, with an emphasis on the trigger system. The event reconstruction algorithm is quickly described, and preliminary measurements of the polarisation of 11 MeV photons are shown.

Detection of the F meson production in the e+e--annihilation at a c.m. energy at 4.4 GeV

International Nuclear Information System (INIS)

Brandelik, R.

1981-01-01

The aim of this thesis had been to detect the F mesons via their decay into eta mesons. For this the eta rate between 4 and 5 GeV c.m. energy had been determined via the decay of the eta mesons into two photons. Energy and direction of the decay photons had been measured in the interior detector of DASP. As result of the analysis three c.m. energy intervals resulted with eta rates different from zero. An exceptionally evident eta signal of sigmasub(eta) = (5.15 +- 1.65)nb+-40% syst. error was measured for c.m. energies around 4.42 GeV and yielded thereby a first evidence for the F production. The detection of the F production resulted finally also in this energy interval from the measurement of the exclusive decay Fsup(+-)->πsup(+-)eta. From the additional detection of a correlation between produced eta mesons and low energy photons γsub(L) (Eγ + e - ->F + Fsup(-*) respectively e + e - ->Fsup(+*)Fsup(-*) was concluded. Thereby finally via a kinematic fit the detection of 6 events succeeded over a background of 0.2 events from e + e - ->F + Fsup(-*) respectively e + e - ->Fsup(+*)Fsup(-*) and Fsup(*)->γsub(L)F, Fsup(+-)->πsup(+-)eta,eta->2γ. Thereby the mass of F and Fsup(*) was determined to msub(F) = (2.04 +- 0.06)GeV and msub(F*) = (2.15 +- 0.06)MeV. The cross section for the 6 signal events was estimated to sigma(e + e - ->F + Fsup(-*))xB.R. (Fsup(+-)->πsup(+-)eta) = (0.41 +- 0.18)nb +-40% syst. error. (orig./HSI) [de

High-resolution measurements of sup(58,60,62)Ni(p,p) scattering cross section in the proton energy range of 3.0 to 4.0 MeV

International Nuclear Information System (INIS)

Arai, Eiichi; Ogawa, Masao

1976-01-01

Differential cross sections were measured at four angles for proton scattering on sup(58,60,62)Ni at energies from 3.0 to 4.0 MeV by using a high-resolution beam from the Tokyo Institute of Technology 4 MV Van de Graaff. An overall resolution of 400 eV (FWHM) was realized using thin solid targets. (author)

Measurement of omega, the energy required to create an ion pair, for 150-MeV protons in nitrogen and argon

International Nuclear Information System (INIS)

Petti, P.L.

1985-01-01

The purpose of this thesis is to provide a 1% measurement of omega, the energy required to produce an ion pair, for 150 MeV protons in various gases. Such a measurement should improve the accuracy of proton ionization chamber dosimetry at the Harvard Cyclotron Laboratory. Currently, no measurements of omega exist in the energy range of 30 to 150 MeV, and present ionization chamber dosimetry at the Cyclotron relies on average values of measurements at lower and higher energies (i.e. for E < 3 MeV and E = 340 MeV). Contrary to theoretical expectations, these low and high energy data differ by as much as 9% in some gases. The results of this investigation demonstrate that the existing high energy data is probably in error, and current proton ionization chamber dosimetry underestimates omega, and hence the proton dose, by 5%

Inclusive momentum and angular distributions from electron positron annihilation at √s = 3.0, 3.8, and 4.8 GeV

International Nuclear Information System (INIS)

Hollebeek, R.

1975-05-01

Inclusive features of multi-hadron final states produced in the annihilations of electrons and positrons are presented. Data were taken at the colliding beam machine, SPEAR, at center-of-mass energies 3.0 GeV, 3.8 GeV, and 4.8 GeV. Reaction products were detected in an approximately 20 m 3 collection of spark chambers and counters, cylindrically arranged, in an axial magnetic field of approximately 4 KG, around the e + e - intersection region. Distributions of single-particle momenta and production angle and two-particle correlations are presented and compared with dynamical models. The results are in disagreement with expectations based on the successful parton--quark model of hadron structure. No generally satisfactory interpretation is available. (U.S.)

The low energy particle detector SLED (≅30 keV-3.2 MeV) and its performance on the Phobos mission to Mars and its moons

International Nuclear Information System (INIS)

McKenna-Lawlor, S.; Afonin, V.V.; Gringauz, K.I.; O'Sullivan, D.; Thompson, A.; Somogyi, A.J.; Szabo, L.; Varga, A.

1990-01-01

A low energy particle detector system (SLED) is described which was designed to measure the flux densities of electrons and ions in the energy range from ∝30 keV to a few MeV in (a) the varying solar aspect angles and temperatures pertaining during the Cruise Phase of the Phobos Mission and (b) in the low temperature environment (reaching -25deg C) pertaining during Mars Encounter. Representative data illustrating the excellent functioning of SLED during both phases of the mission are presented. (orig.)

Measurements of neutron spectra produced from a thick tungsten target bombarded with 5 and 15 GeV protons

CERN Document Server

Meigo, S; Shigyo, N; Iga, K; Iwamoto, Y; Kitsuki, H; Ishibashi, K; Maehata, K; Arima, H; Nakamo, T; Numajiri, M

2002-01-01

For validation of calculation codes that are employed in the design of a pulse spallation neutron source and accelerator driven system, the spectrum of neutrons produced from a thick target plays an important role. However, appropriate experimental data were scarce for incident energies higher than 0.8 GeV. In this study, the spectrum from a thick tungsten target was measured. The experiment was carried out at the pi 2 beam line of the 12-GeV proton synchrotron at KEK. The tungsten target was bombarded by 0.5- and 1.5-GeV secondary protons. The spectrum of neutrons was measured by the time-of-flight technique using organic scintillators of NE213. The calculated result with NMTC/JAM and MCNP-4A is compared with the measured data. It is found that the NMTC/JAM generally gives a good agreement with experiment. The NMTC/JAM, however, gives 50% lower neutron flux in the energy region 20~80 MeV, which is consistent with the results in a previous comparison of a lead target. For the neutrons between 20 and 80 MeV, t...

Tritons at energies of 10 MeV to 1 TeV: Conversion coefficients for fluence-to-absorbed dose, equivalent dose, effective dose, and gray equivalent, calculated using Monte Carlo radiation transport code MCNPX 2.7.C

International Nuclear Information System (INIS)

Copeland, K.; Parker, D. E.; Friedberg, W.

2010-01-01

Conversion coefficients were calculated for fluence-to-absorbed dose, fluence-to-equivalent dose, fluence-to-effective dose and fluence-to-gray equivalent for isotropic exposure of an adult female and an adult male to tritons ( 3 H + ) in the energy range of 10 MeV to 1 TeV (0.01-1000 GeV). Coefficients were calculated using Monte Carlo transport code MCNPX 2.7.C and BodyBuilder TM 1.3 anthropomorphic phantoms. Phantoms were modified to allow calculation of effective dose to a Reference Person using tissues and tissue weighting factors from 1990 and 2007 recommendations of the International Commission on Radiological Protection (ICRP) and calculation of gray equivalent to selected tissues as recommended by the National Council on Radiation Protection and Measurements. At 15 of the 19 energies for which coefficients for effective dose were calculated, coefficients based on ICRP 2007 and 1990 recommendations differed by less than 3%. The greatest difference, 43%, occurred at 30 MeV. Published by Oxford Univ. Press on behalf of the US Government 2010. (authors)

Deuterons at energies of 10 MeV to 1 TeV: Conversion coefficients for fluence-to-absorbed dose, equivalent dose, effective dose and gray equivalent, calculated using Monte Carlo radiation transport code MCNPX 2.7.C

International Nuclear Information System (INIS)

Copeland, K.; Parker, D. E.; Friedberg, W.

2011-01-01

Conversion coefficients were calculated for fluence-to-absorbed dose, fluence-to-equivalent dose, fluence-to-effective dose and fluence-to-gray equivalent for isotropic exposure of an adult female and an adult male to deuterons ( 2 H + ) in the energy range 10 MeV -1 TeV (0.01-1000 GeV). Coefficients were calculated using the Monte Carlo transport code MCNPX 2.7.C and BodyBuilder TM 1.3 anthropomorphic phantoms. Phantoms were modified to allow calculation of the effective dose to a Reference Person using tissues and tissue weighting factors from 1990 and 2007 recommendations of the International Commission on Radiological Protection (ICRP) and gray equivalent to selected tissues as recommended by the National Council on Radiation Protection and Measurements. Coefficients for the equivalent and effective dose incorporated a radiation weighting factor of 2. At 15 of 19 energies for which coefficients for the effective dose were calculated, coefficients based on ICRP 1990 and 2007 recommendations differed by < 3 %. The greatest difference, 47 %, occurred at 30 MeV. (authors)

Inclusive production of Φ-mesons in neutron-proton interactions at 30-70 GeV

International Nuclear Information System (INIS)

Aleev, A.N.; Aref'ev, V.A.; Balandin, V.P.

1989-01-01

A signal of decays Φ→K + K - has been observed in neutron-hydrogen interactions at energies 30-70 GeV in a experiment using the BIS-2 spectrometer. The longitudinal momentum spectrum in the forward region of Feynman variable x F >0.1 at P T F ) N with N=4.28±0.42. The p T 2 -spectrum was parametrized by the exponent exp(-3.02xp T 2 ) The extrapolation of the measured cross section to the full kinematic region yields a value of 220±85 μb. 15 refs.; 7 figs.; 1 tab

Neutron yield and induced radioactivity: a study of 235-MeV proton and 3-GeV electron accelerators.

Science.gov (United States)

Hsu, Yung-Cheng; Lai, Bo-Lun; Sheu, Rong-Jiun

2016-01-01

This study evaluated the magnitude of potential neutron yield and induced radioactivity of two new accelerators in Taiwan: a 235-MeV proton cyclotron for radiation therapy and a 3-GeV electron synchrotron serving as the injector for the Taiwan Photon Source. From a nuclear interaction point of view, neutron production from targets bombarded with high-energy particles is intrinsically related to the resulting target activation. Two multi-particle interaction and transport codes, FLUKA and MCNPX, were used in this study. To ensure prediction quality, much effort was devoted to the associated benchmark calculations. Comparisons of the accelerators' results for three target materials (copper, stainless steel and tissue) are presented. Although the proton-induced neutron yields were higher than those induced by electrons, the maximal neutron production rates of both accelerators were comparable according to their respective beam outputs during typical operation. Activation products in the targets of the two accelerators were unexpectedly similar because the primary reaction channels for proton- and electron-induced activation are (p,pn) and (γ,n), respectively. The resulting residual activities and remnant dose rates as a function of time were examined and discussed. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Absolute differential cross sections for π±p elastic scattering at 30 ≤ Tπ ≤ 67 MeV

International Nuclear Information System (INIS)

Brack, J.T.; Ristinen, R.A.; Kraushaar, J.J.

1989-11-01

Absolute π±p differential cross sections have been measured at incident pion energies of 30.0, 45.0, and 66.8 MeV, using active targets of scintillator plastic (CH 1.1 ) to detect recoil protons in coincidence with scattered pions. Statistical uncertainties are typically ±3%; systematic uncertainties are ±2%. The results are consistent with two earlier measurements by this group employing different experimental techniques at 67 MeV and higher incident pion energies. The π - p cross sections are in good agreement with currently accepted phase-shift analyses, but the corresponding π + p predictions are typically 15% higher at large angles than the π + p data reported here

Investigation of transversal nuclear excitation in 208Pb at excitation energies between 6 MeV and 8 MeV using inelastic electron scattering

International Nuclear Information System (INIS)

Frey, R.W.

1978-01-01

Using high resolution inelastic electron scattering magnitic dipole and quadrupole excitations in 208 Pb were investigated in the energy range between 6 MeV and 8 MeV. The electron energy was 50 MeV and 63.5 MeV. With a mean absolute energy resolution of 33 kev. 44 excited states were found in the above energy range. The measured angular distributions were compared with DWBA-calculations using random phase approximated wave functions. (FKS)

Progress report 1 October 1976-30 September 1977

International Nuclear Information System (INIS)

This progress report presents the researches and the technological studies carried out at the Nuclear Physics Department of Saclay from october 1st, 1976 to September 30, 1977. These studies concern the nuclear structure and reaction mechanisms. They have been performed on the tandem accelerator of 8.5 MeV, the 600 MeV electron linear accelerator and the high resolution spectrometer for 1 GeV protons at the Saturne synchrotron [fr

Elastic scattering of polarized deuterons from hydrogen at 2.0, 1.6, and 1.2 GeV and search for critical opalescence in inelastic scattering of protons from carbon-12 at 800 MeV

International Nuclear Information System (INIS)

Haji-Saeid, S.M.

1981-01-01

Large deuteron vector and tensor asymmetries were measured for the first time at intermediate energies. The polarized deuteron beam (with tensor and vector components of 0.75 and 0.25, respectively) was used at energies of 2.0, 1.6, and 1.2 GeV. The tensor and vector quantities P/sub yy/ and P/sub y/ were extracted from the data obtained within beam polarization normal to the scattering plane, and P/sub xx/ was obtained when the polarization was precessed into the scattering plane. Analysis of the data using multiple scattering theory demonstrates the importance of the noneikona correction to the Glauber Model and also the sensitivity of the data to double-spin flip components of the NN amplitudes. The differential cross section for the 12 C(p,p') 12 C* (15.11 MeV, 1 + , T=1) reaction was measured at 800 MeV; the range of the angular distribution corresponds to momentum transfers of 0.7 to 2.4 fm -1 (1 to 3.3 m/sub π/). The cross section decreases almost exponentially at large angles; no maximum is observed in the region where nuclear critical opalescence might be expected. Cross sections measured in parallel to the 15.11-MeV state were for the levels at 11.83 (2 - ), 12.71 (1 + ), 13.35 (2 - ), 16.1 (2 + ), and 16.58 (2 - ) MeV. 86 figures 18 tables

A search for new vector mesons in the mass range between 0.9 and 2.2 GeV

International Nuclear Information System (INIS)

Bartalucci, S.; Bertolucci, S.; Bradaschia, C.; Fiori, M.; Fong, D.; McCorriston, T.; Giromini, P.; Guiducci, S.; Rippich, C.; Rohde, M.; Sermoneta, A.; Trasatti, L.

1977-01-01

The yield of e + e - pairs in the reaction γp→ pe + e - in the invariant mass region 0.9( 2 has been measured. The result, based on 2x10 4 events, shows with a statistical significance of 7 standard deviations a new resonance-like single structure with width 5(<=)30 MeV at M approximately 1100 MeV. For 1.2(<=)M (<=)1.8 GeV the data exhibit an additional wide structure, which can be accounted for by two broad resonances at about 1400 and 1700 MeV. The existence of the rho'(1250) and rho''(1600) is neither proven nor excluded by the data

High-energy gamma-ray astronomy and the COS-B mission

International Nuclear Information System (INIS)

Wills, R.D.

1977-01-01

The most significant results in gamma-ray astronomy have been produced by satellite- and balloon-borne instruments sensitive in the range 30 MeV to approximately 10 GeV. The COS-B instrument which is described is typical of this type of detector. For this reason the review of gamma-ray production mechanisms gives greater attention to those processes which are specifically important in that energy range. (orig.) [de

LEAP: A balloon-borne search for low-energy cosmic ray antiprotons

Science.gov (United States)

Moats, Anne Rosalie Myers

The LEAP (Low Energy Antiproton) experiment is a search for cosmic ray antiprotons in the 120 MeV to 1.2 GeV kinetic energy range. The motivation for this project was the result announced by Buffington et al. (1981) that indicated an anomalously high antiproton flux below 300 MeV; this result has compelled theorists to propose sources of primary antiprotons above the small secondary antiproton flux produced by high energy cosmic ray collisions with nuclei in the interstellar medium. LEAP consisted of the NMSU magnet spectrometer, a time-of-flight system designed at NASA-Goddard, two scintillation detectors, and a Cherenkov counter. Analysis of flight data performed by the high energy astrophysics group at Goddard Space Flight Center revealed no antiproton candidates found in the 120 MeV to 360 MeV range; 3 possible antiproton candidate events were found in the 500 MeV to 1.2 GeV range in an analysis done here at the University of Arizona. However, since it will be necessary to sharpen the calibration on all of the LEAP systems in order to positively identify these events as antiprotons, only an upper limit has been determined at present. Thus, combining the analyses performed at the University of Arizona and NASA-Goddard, 90 percent confidence upper limits of 3.5 x 10-5 in the 120 MeV to 360 MeV range and 2.3 x 10-4 in the 500 MeV to 1.2 GeV range for the antiproton/proton ratio is indicated by the LEAP results. LEAP disagrees sharply with the results of the Buffington group, indicating a low antiproton flux at these energies. Thus, a purely secondary antiproton flux may be adequate at low energies.

The low energy particle detector SLED ( approx equal 30 keV-3. 2 MeV) and its performance on the Phobos mission to Mars and its moons

Energy Technology Data Exchange (ETDEWEB)

McKenna-Lawlor, S. (Saint Patrick' s Coll., Maynooth (Ireland) Space Technology Ireland Ltd., Maynooth (Ireland)); Afonin, V.V.; Gringauz, K.I. (AN SSSR, Moscow (USSR). Inst. Kosmicheskikh Issledovanij); Keppler, E.; Kirsch, E.; Richter, A.; Witte, M. (Max-Planck-Institut fuer Aeronomie, Katlenburg-Lindau (Germany, F.R.)); O' Sullivan, D.; Thompson, A. (Dublin Inst. for Advanced Studies (Ireland)); Somogyi, A.J.; Szabo, L.; Varga, A. (Hungarian Academy of Sciences, Budapest (Hungary). Central Research Inst. for Physics)

1990-05-01

A low energy particle detector system (SLED) is described which was designed to measure the flux densities of electrons and ions in the energy range from {proportional to}30 keV to a few MeV in (a) the varying solar aspect angles and temperatures pertaining during the Cruise Phase of the Phobos Mission and (b) in the low temperature environment (reaching -25deg C) pertaining during Mars Encounter. Representative data illustrating the excellent functioning of SLED during both phases of the mission are presented. (orig.).

Observation of a spin 4 neutral meson with 2 GeV mass decaying in π0π0

International Nuclear Information System (INIS)

Apel, W.D.; Augenstein, K.; Bertolucci, E.; Donskov, S.V.; Inyakin, A.V.; Kachanov, V. A.; Kittenberger, W.; Krasnokutsky, R.N.; Kruger, M.; Leder, G.

1975-01-01

The invariant mass spectrum of neutral meson states from π - p interactions at 40 GeV/c incident momentum has been investigated in a high statistics experiment performed at the 70 GeV IHEP accelerator. To detect the high energy photons coming from the produced neutral states, a hodoscope spectrometer with a computer on-line was used. A clear structure on the mass spectrum of dipions produced in the reaction π - p → π 0 π 0 n is observed at 2 GeV. The decay angular distributions show in this mass region the variation with mass typical of a state with a spin J = 4. The mass of the observed meson is found to be M (2020 +- 25) MeV and the estimate of the full width is (180 +- 50) MeV

Risk assessment of 30 MeV cyclotron facilities

Energy Technology Data Exchange (ETDEWEB)

Jeong, Gyo Seong; Lee, Jin Woo [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Kim, Chong Yeal [Dept. of Radiation Science and Technology, Chonbuk National University, Jeonju (Korea, Republic of)

2017-03-15

A cyclotron is a kind of particle accelerator that produces a beam of charged particles for the production of medical, industrial, and research radioisotopes. More than 30 cyclotrons are operated in Korea to produce 18F, an FDG synthesis at hospitals. A 30-MeV cyclotron was installed at ARTI (Advanced Radiation Technology Institute, KAERI) mainly for research regarding isotope production. In this study, we analyze and estimate the items of risk such as the problems in the main components of the cyclotron, the loss of radioactive materials, the leakage of coolant, and the malfunction of utilities, fres and earthquakes. To estimate the occurrence frequency in an accident risk assessment, five levels, i.e., Almost certain, Likely, Possible, Unlikely, and Rare, are applied. The accident consequence level is classified under four grades based on the annual permissible dose for radiation workers and the public in the nuclear safety law. The analysis of the accident effect is focused on the radioactive contamination caused by radioisotope leakage and radioactive material leakage of a ventilation filter due to a free. To analyze the risks, Occupation Safety and Health Acts is applied. In addition, action plans against an accident were prepared after a deep discussion among relevant researchers. In this acts, we will search for hazard and introduce the risk assessment for the research 30-MeV cyclotron facilities of ARTI.

Risk assessment of 30 MeV cyclotron facilities

International Nuclear Information System (INIS)

Jeong, Gyo Seong; Lee, Jin Woo; Kim, Chong Yeal

2017-01-01

A cyclotron is a kind of particle accelerator that produces a beam of charged particles for the production of medical, industrial, and research radioisotopes. More than 30 cyclotrons are operated in Korea to produce 18F, an FDG synthesis at hospitals. A 30-MeV cyclotron was installed at ARTI (Advanced Radiation Technology Institute, KAERI) mainly for research regarding isotope production. In this study, we analyze and estimate the items of risk such as the problems in the main components of the cyclotron, the loss of radioactive materials, the leakage of coolant, and the malfunction of utilities, fres and earthquakes. To estimate the occurrence frequency in an accident risk assessment, five levels, i.e., Almost certain, Likely, Possible, Unlikely, and Rare, are applied. The accident consequence level is classified under four grades based on the annual permissible dose for radiation workers and the public in the nuclear safety law. The analysis of the accident effect is focused on the radioactive contamination caused by radioisotope leakage and radioactive material leakage of a ventilation filter due to a free. To analyze the risks, Occupation Safety and Health Acts is applied. In addition, action plans against an accident were prepared after a deep discussion among relevant researchers. In this acts, we will search for hazard and introduce the risk assessment for the research 30-MeV cyclotron facilities of ARTI

NUCLEAR CROSS-SECTION CALCULATIONS IN THE 1 MEV TO 5 GEV RANGE WITH COMBINED SEMI-CLASSICAL AND QUANTUM MECHANICAL MODELS

Energy Technology Data Exchange (ETDEWEB)

Guimaraes, F.B.

2002-03-07

In this work we describe neutron and proton induced reaction cross-sections for iron produced by the codes TNG and CEM95 in the 5 to 300 MeV energy range. TNG calculations cover the 5-90 MeV range, while CEM95 covers the 50-300 MeV high energy range. The two codes show some disagreements in the overlap energy range, both among themselves and with the experimental data, which are presently being addressed. The experimental data used are from NNDC and/or from LA150 NSE references. We also describe some developments for combining TNG and CEM95 into a new code called CETNG (Cascade Exciton TNG).

Search for a 'top' threshold in hadronic e+e- annihilation at energies between 22 and 31.6 GeV

International Nuclear Information System (INIS)

Berger, C.; Genzel, H.; Grigull, R.; Lackas, W.; Raupach, F.; Ackermann, H.

1979-09-01

Results on e + e - annihilation into hadrons at c.m. energies between 22 and 31.6 GeV are presented. The data was accumulated with the PLUTO detector at PETRA. The events are dominantly of the two-jet type. The value of the relative hadronic cross section R = 3.88 +- 0.22 along with the details of the sphericity and thrust distribution rule out an open (t anti t) channel (Qsub(t) = 2/3) below 30 GeV. The inclusive muon results support the above conclusion. (orig.)

Measurements of neutron spectra produced from a thick tungsten target bombarded with 0.5- and 1.5-GeV protons

International Nuclear Information System (INIS)

Meigo, Shin-ichiro; Takada, Hiroshi

2002-01-01

For validation of calculation codes that are employed in the design of pulse spallation neutron source and accelerator driven system, spectrum of neutrons produced from a thick target plays an important role. However, appropriate experimental data were scarce for the incident energies higher than 0.8 GeV. In this study, the spectrum from a thick tungsten target was measured. The experiment was carried out at the π2 beam line of the 12-GeV proton synchrotron at KEK. The tungsten target was bombarded by the 0.5- and 1.5-GeV secondary protons. Spectrum of neutrons was measured by the time-of-flight technique using organic scintillators of NE213. The calculated result with NMTC/JAM and MCNP-4A is compared with the measured data. It is found that the NMTC/JAM generally gives a good agreement with experiment. The NMTC/JAM, however, gives 50% lower neutron flux in the energy region 20∼80 MeV, which is consistent with the results in previous comparison of lead target. For the neutrons between 20 and 80 MeV, the calculation using with the in-medium nucleon-nucleon cross sections reproduced the experiment fairly well. (author)

Experimental study of spallation: neutron angular distributions induced by protons (0.8.,1.2 et 1.6 GeV) and deuterons (0.8 et 1.6 GeV) beams

International Nuclear Information System (INIS)

Borne, F.

1998-01-01

Angular distributions of spallation neutrons, produced by 0,8 to 1,6 GeV protons and 0,8 to 1,6 GeV deuterons, with two experimental and complementary techniques: the flight time measure and the use of a liquid hydrogen converter associated with a magnetic spectrometer of higher energy (2000 MeV). Experimental results obtained at Saturne (Cea) are analysed and interpreted. They allowed the determination of the neutrons production behaviour on thin targets (Al, Fe, Zr, W, Pb and Th) in function of the angle emission and the atomic number of the target and to compare the variation of neutrons production, coming from protons and incident deuterons of same total energy on a Pb target. Experimental results are compared with simulation results obtained with the TIERCE code, including Bertini and Cugnon intra-nuclear cascades. (A.L.B.)

Study of energy-energy correlations between 12 and 46. 8 GeV c. m. energies

Energy Technology Data Exchange (ETDEWEB)

Braunschweig, W; Gerhards, R; Kirschfink, F J; Martyn, H U; Rosskamp, P; Bock, B; Eisenmann, J; Fischer, H M; Hartmann, H; Hilger, E

1987-10-01

We present data on energy-energy correlations (EEC) and their related asymmetry (AEEC) in e/sup +/e/sup -/ annihilation in the centre of mass energy range 12GeV. The energy and angular dependence of the EEC in the central region is well described by O(..cap alpha../sub s//sup 2/) QCD plus a fragmentation term proportional to 1/..sqrt..s. Bare O(..cap alpha../sub s//sup 2/) QCD reproduces our data for the large angle region of the AEEC. Nonperturbative effects for the latter are estimated with the help of fragmentation models. From various analyses using different approximations, we find that values for ..lambda.. sub(anti Manti S) in the range 0.1-0.3 GeV give a good description of the data. We also compare analytical calculations in QCD for the EEC in the back-to-back region to our data. The theoretical predictions describe well both the angular and energy dependence of the data in the back-to-back region.

207,208Pb(n,xnγ) reactions for neutron energies from 3 to 200 MeV

International Nuclear Information System (INIS)

Vonach, H.; Pavlik, A.; Chadwick, M.B.; Haight, R.C.; Nelson, R.O.; Wender, S.A.; Young, P.G.

1994-01-01

High-resolution γ-ray spectra from the interaction of neutrons in the energy range from 3 to 200 MeV with 207,208 Pb were measured with the white neutron source at the weapons neutron research (WNR) facility at Los Alamos National Laboratory. From these data, excitation functions for prominent γ transitions in 200,202,204,206,207,208 Pb were derived from threshold to 200 MeV incident neutron energy. These γ-production cross sections reflect the excitation cross sections for the respective residual nuclei. The results are compared with the predictions of nuclear reaction calculations based on the exciton model for precompound emission, the Hauser-Feshbach theory for compound nucleus decay, and coupled channels calculations to account for direct excitation of collective levels. Good agreement was obtained over the entire energy range covered in the experiment with reasonable model parameters. The results of this work clearly demonstrate that multiple preequilibrium emission has to be taken into account above about 40 MeV, and that the level density model of Ignatyuk, which accounts for the gradual disappearance of shell effects with increasing excitation energy, should be used instead of the Gilbert-Cameron and backshifted Fermi-gas models if excitation energies exceed about 30 MeV. No indication for a reduction of the nuclear moment of inertia below the rigid body value was found

Development of a Telescope for Medium-Energy Gamma-ray Astronomy

Science.gov (United States)

Sunter, Stan

2012-01-01

Since the launch of AGILE and FERMI, the scientific progress in high-energy (Eg greater than approximately 200 MeV) gamma-ray science has been, and will continue to be dramatic. Both of these telescopes cover a broad energy range from approximately 20 MeV to greater than 10 GeV. However, neither instrument is optimized for observations below approximately 200 MeV where many astrophysical objects exhibit unique, transitory behavior, such as spectral breaks, bursts, and flares. Hence, while significant progress from current observations is expected, there will nonetheless remain a significant sensitivity gap in the medium-energy (approximately 0.1-200 MeV) regime; the lower end of this range remains largely unexplored whereas the upper end will allow comparison with FERMI data. Tapping into this unexplored regime requires significant improvements in sensitivity. A major emphasis of modern detector development, with the goal of providing significant improvements in sensitivity in the medium-energy regime, focuses on high-resolution electron tracking. The Three-Dimensional Track Imager (3-DTI) technology being developed at GSFC provides high resolution tracking of the electron-positron pair from gamma-ray interactions from 5 to 200 MeV. The 3-DTI consists of a time projection chamber (TPC) and 2-D cross-strip microwell detector (MWD). The low-density and homogeneous design of the 3-DTI, offers unprecedented sensitivity by providing angular resolution near the kinematic limit. Electron tracking also enables measurement of gamma-ray polarization, a new tool to study astrophysical phenomenon. We describe the design, fabrication, and performance of a 30x30x30 cm3 3-DTI detector prototype of a medium-energy gamma-ray telescope.

A case for hidden b anti b tetraquarks based on e+e- → b anti b cross sections between √(s) = 10.54 and 11.20 GeV

International Nuclear Information System (INIS)

Ali, Ahmed; Hambrock, Christian; Ahmed, Ishtiaq; Aslam, M. Jamil

2009-11-01

We study the spectroscopy and dominant decays of the bottomonium-like tetraquarks (bound diquarks-antidiquarks), focusing on the lowest lying P-wave [bq][anti b anti q] states Y [bq] (with q=u,d), having J PC =1 -- . To search for them, we analyse the BABAR data obtained during an energy scan of the e + e - →b anti b cross section in the range of √(s)=10.54 to 11.20 GeV. We find that these data are consistent with the presence of an additional b anti b state Y [bq] with a mass of 10.90 GeV and a width of about 30 MeV apart from the Υ(5S) and Υ(6S) resonances. A closeup of the energy region around the Y [bq] -mass may resolve this state in terms of the two mass eigenstates, Y [b,l] and Y [b,h] , with a mass difference, estimated as about 6 MeV. We tentatively identify the state Y [bq] (10900) from the R b -scan with the state Y b (10890) observed by BELLE in the process e + e - →Y b (10890)→Υ(1S,2S)π + π - due to their proximity in masses and decay widths. (orig.)

Recoil proton polarization of neutral pion photoproduction from proton in the energy range between 400 MeV and 1142 MeV

International Nuclear Information System (INIS)

Kato, S.; Miyachi, T.; Sugano, K.; Toshioka, K.; Ukai, K.

1979-08-01

The recoil proton polarization of the reaction γp → π 0 p were measured at a C.M. angle of 100 0 for incident photon energies between 451 and 1106 MeV, and at an angle of 130 0 for energies from 400 MeV to 1142 MeV. One photon decayed from a π 0 -meson and a recoil proton were detected in coincidence. Two kinds of polarization scatterers were employed. In the range of proton kinetic energy less than 420 MeV and higher than 346 MeV, carbon plates and liquid hydrogen were used for determining the polarization. Results are compared with recent phenomenological analyses. From the Comparison between the present data and the asymmetry data given by the polarized target, the contribution of the invariant amplitudes A 3 can be estimated to be small at 100 0 . (author)

Determination of the optimal conditions for simultaneous production of 73SE and 75SE radioisotopes in a 30 MeV cyclotron

International Nuclear Information System (INIS)

Pejman Rowshanfazad; Amirreza Jalilian; Mahsheed Sabet

2004-01-01

enrichment process, due to the presence of arsenic as 75 As(100%) in nature. On the other hand, chemical separation could be carried out in simple, inexpensive methods in a short time, due to the difference between target materials and the products. So the above reactions were taken to be the best choices according to the present conditions and facilities. 2 Cross Section Calculations for 75 As Reactions with Protons. Characterization of excitation function is a very important step for the determination of the projectile beam energy range. Excitation function can be determined by using computer codes such as ALICE (21) or experimental methods. In the present research, performed in the cyclotron department of Atomic Energy Organization of Iran (IBA, Cyclone-30), 75 As reaction cross-sections with protons were calculated for beam energy range of 3-30 MeV (this cyclotron can accelerate protons to 30 MeV energy) using ALICE code and the results were compared with previous experimental data given in the literature (19, 22, 23). The results of this comparison are shown in figure 1. Figure 1 shows a good agreement between the results of ALICE code and the experimental data. The three main reactions were 75 As(p, n) 75 Se, 75 As(p, pn) 74 Se and 75 As(p, 3n) 73 Se. Production of 75 Se began at about 2 MeV and reached its maximum around 12 MeV, where the reaction cross section was about 840 mb. Production of 74 As began around 13 MeV and reached its maximum at about 26 MeV, where the reaction cross section was about 170 mb. 74 As (which was considered as impurity) has a half life of 17.8 days, so it could be easily separated from the product by efficient chemical methods and it was not taken into account while energy selection. Production of 73 Se began at around 22 MeV proton energy and continued to increase while beam energy increased to 30 MeV, where the reaction cross section was about 550 mb. Thus, if the target thickness would be enough to reduce the proton energy from 22 MeV

Aspects of strangeness production with 15 -- 30 GeV proton beams

International Nuclear Information System (INIS)

Dover, C.B.

1992-04-01

We discuss the spectrum of physics questions related to strangeness which could be addressed with a 15--30 GeV proton storage ring. We focus on various aspects of strangeness production, including hyperon production in pp collisions, studies of hyperon-nucleon scattering, production of hyper-fragments in p-nucleus collisions, and hyperon spin observables in inclusive production

Fermi LAT Observations of LS I +61 303: First Detection of an Orbital Modulation in GeV Gamma Rays

Energy Technology Data Exchange (ETDEWEB)

Abdo, A.A.; /Federal City Coll. /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.; Atwood, W.B.; /UC, Santa Cruz; Axelsson, M.; /Stockholm U., OKC /Stockholm U.; Baldini, L.; /INFN, Pisa; Ballet, J.; /DAPNIA, Saclay; Barbiellini, G.; /INFN, Trieste /Trieste U.; Bastieri, D.; /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; Berenji, B.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Blandford, R.; /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept.; Bloom, E.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 /Washington U., Seattle /Bari U. /INFN, Bari /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /IASF, Milan /Milan Polytechnic /DAPNIA, Saclay /ASDC, Frascati /INFN, Perugia /Perugia U. /NASA, Goddard /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /DAPNIA, Saclay /Naval Research Lab, Wash., D.C. /George Mason U. /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. /Sonoma State U. /Stockholm U., OKC /Royal Inst. Tech., Stockholm /Stockholm U. /DAPNIA, Saclay /NASA, Goddard /CSST, Baltimore /ASDC, Frascati /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. /SLAC /Stanford U., HEPL /KIPAC, Menlo Park /Stanford U., Phys. Dept. /Grenoble, CEN; /more authors..

2012-04-02

This Letter presents the first results from the observations of LS I +61{sup o}303 using Large Area Telescope data from the Fermi Gamma-Ray Space Telescope between 2008 August and 2009 March. Our results indicate variability that is consistent with the binary period, with the emission being modulated at 26.6 {+-} 0.5 days. This constitutes the first detection of orbital periodicity in high-energy gamma rays (20 MeV-100 GeV, HE). The light curve is characterized by a broad peak after periastron, as well as a smaller peak just before apastron. The spectrum is best represented by a power law with an exponential cutoff, yielding an overall flux above 100 MeV of 0.82 {+-} 0.03(stat) {+-} 0.07(syst) 10{sup -6} ph cm{sup -2} s{sup -1}, with a cutoff at 6.3 {+-} 1.1(stat) {+-} 0.4(syst) GeV and photon index {Gamma} = 2.21 {+-} 0.04(stat) {+-} 0.06(syst). There is no significant spectral change with orbital phase. The phase of maximum emission, close to periastron, hints at inverse Compton scattering as the main radiation mechanism. However, previous very high-energy gamma ray (>100 GeV, VHE) observations by MAGIC and VERITAS show peak emission close to apastron. This and the energy cutoff seen with Fermi suggest that the link between HE and VHE gamma rays is nontrivial.

OBSERVATIONS OF HIGH-ENERGY COSMIC-RAY ELECTRONS FROM 30 GeV TO 3 TeV WITH EMULSION CHAMBERS

Energy Technology Data Exchange (ETDEWEB)

Kobayashi, T. [Department of Physics and Mathematics, Aoyama Gakuin University, Sagamihara 252-5258 (Japan); Komori, Y. [Faculty of Health and Social Services, Kanagawa University of Human Services, Yokosuka 238-0013 (Japan); Yoshida, K.; Yanagisawa, K. [College of Systems Engineering and Science, Shibaura Institute of Technology, Saitama 337-8570 (Japan); Nishimura, J.; Yamagami, T.; Saito, Y. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara 229-8510 (Japan); Tateyama, N. [Faculty of Engineering, Kanagawa University, Yokohama 221-8686 (Japan); Yuda, T. [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa 277-8582 (Japan); Wilkes, R. J., E-mail: tadasik-112850@jasper.dti.ne.jp, E-mail: komori-y@kuhs.ac.jp, E-mail: yoshida@shibaura-it.ac.jp, E-mail: nisimura@icrr.u-tokyo.ac.jp, E-mail: tateyama@n.kanagawa-u.ac.jp, E-mail: yuda@icrr.u-tokyo.ac.jp, E-mail: wilkes@u.washington.edu [Department of Physics, University of Washington, Seattle, WA 98195-1560 (United States)

2012-12-01

We have performed a series of cosmic-ray electron observations using balloon-borne emulsion chambers since 1968. While we previously reported the results from subsets of the exposures, the final results of the total exposures up to 2001 are presented here. Our successive experiments have yielded a total exposure of 8.19 m{sup 2} sr day at altitudes of 4.0-9.4 g cm{sup -2}. The performance of the emulsion chambers was examined by accelerator beam tests and Monte Carlo simulations, and the on-board calibrations were carried out by using the flight data. In this work, we present the cosmic-ray electron spectrum in the energy range from 30 GeV to 3 TeV at the top of the atmosphere, which is well represented by a power-law function with an index of -3.28 {+-} 0.10. The observed data can also be interpreted in terms of diffusive propagation models. The evidence of cosmic-ray electrons up to 3 TeV suggests the existence of cosmic-ray electron sources at distances within {approx}1 kpc and times within {approx}1 Multiplication-Sign 10{sup 5} yr ago.

FERMI OBSERVATIONS OF GRB 090510: A SHORT-HARD GAMMA-RAY BURST WITH AN ADDITIONAL, HARD POWER-LAW COMPONENT FROM 10 keV TO GeV ENERGIES

International Nuclear Information System (INIS)

Ackermann, M.; Bechtol, K.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Borgland, A. W.; Bouvier, A.; Asano, K.; Atwood, W. B.; Axelsson, M.; Baldini, L.; Bellazzini, R.; Bregeon, J.; Ballet, J.; Barbiellini, G.; Baring, M. G.; Bastieri, D.; Bhat, P. N.; Bissaldi, E.; Bonamente, E.

2010-01-01

We present detailed observations of the bright short-hard gamma-ray burst GRB 090510 made with the Gamma-ray Burst Monitor (GBM) and Large Area Telescope (LAT) on board the Fermi observatory. GRB 090510 is the first burst detected by the LAT that shows strong evidence for a deviation from a Band spectral fitting function during the prompt emission phase. The time-integrated spectrum is fit by the sum of a Band function with E peak = 3.9 ± 0.3 MeV, which is the highest yet measured, and a hard power-law component with photon index -1.62 ± 0.03 that dominates the emission below ∼20 keV and above ∼100 MeV. The onset of the high-energy spectral component appears to be delayed by ∼0.1 s with respect to the onset of a component well fit with a single Band function. A faint GBM pulse and a LAT photon are detected 0.5 s before the main pulse. During the prompt phase, the LAT detected a photon with energy 30.5 +5.8 -2.6 GeV, the highest ever measured from a short GRB. Observation of this photon sets a minimum bulk outflow Lorentz factor, Γ∼> 1200, using simple γγ opacity arguments for this GRB at redshift z = 0.903 and a variability timescale on the order of tens of ms for the ∼100 keV-few MeV flux. Stricter high confidence estimates imply Γ ∼> 1000 and still require that the outflows powering short GRBs are at least as highly relativistic as those of long-duration GRBs. Implications of the temporal behavior and power-law shape of the additional component on synchrotron/synchrotron self-Compton, external-shock synchrotron, and hadronic models are considered.

Observation of a resonance at 4.4 GeV and additional structure near 4.1 GeV in e+e- annihilation

International Nuclear Information System (INIS)

Siegrist, J.; Abrams, G.S.; Boyarski, A.M.; Breidenbach, M.; Bulos, F.; Chinowsky, W.; Feldman, G.J.; Friedberg, C.E.; Fryberger, D.; Goldhaber, G.; Hanson, G.; Hartill, D.L.; Jaros, J.; Jean-Marie, B.; Kadyk, J.A.; Larsen, R.R.; Luke, D.; Luth, V.; Lynch, H.L.; Madaras, R.; Morehouse, C.C.; Nguyen, H.K.; Paterson, J.M.; Perl, M.L.; Peruzzi, I.; Pierre, F.M.; Piccolo, M.; Pun, T.P.; Rapidis, P.; Richter, B.; Sadoulet, B.; Schwitters, R.F.; Tanenbaum, W.; Trilling, G.H.; Vannucci, F.; Whitaker, J.S.; Winkelman, F.C.; Wiss, J.E.

1976-01-01

We observe a resonancelike structure in the total cross section for hadron production by e + e - colliding beams at a mass of 4414 +- 7 MeV having a total width GAMMA = 33 +- 10 MeV. From the area under this resonance, we deduce the partial width to electron pairs to be GAMMA/sub ee/ = 440 +- 140 eV. Further structure of comparable width is present near 4.1 GeV

Physics and a plan for a 45 GeV facility that extends the high-intensity capability in nuclear and particle physics

International Nuclear Information System (INIS)

1986-05-01

A proposed program of physics research to be carried out at a 45 GeV high-intensity proton accelerator is discussed. In addition to a general discussion of the potentially most productive research directions, specific experiments in strong and flavor physics are presented. The proposed strong interaction physics deals with investigation of nonperturbative QCD through the study of exotic hadrons and measurement of nuclear medium effects on flavor-specific quark momentum distribution. The major part of the proposed program in flavor interaction physics probes possible physics beyond the minimal standard model. A design using two synchrotrons produces a 45 GeV proton beam by increasing the energy of the present LAMPF 800 MeV beam. A booster operating at 60 Hz accelerates 144 μA from 800 MeV to 6 GeV while the main ring operating at 3.33 Hz accelerates 32 μA from 6 GeV to 45 GeV. The 112 μA at 6 GeV which is not further accelerated is used to create intense beams of neutrinos and pulsed muons. The 32 μA of 45 GeV beam is slow extracted into an existing experimental area in which a large number of high-intensity, high-purity kaon and other secondary beams will be produced. A proposed layout of the experimental areas along with the characteristics of the secondary beams is also presented. The report concludes with a cost estimate to construct such a facility at Los Alamos

Study of the thermal oxidation of titanium and zirconium under argon ion irradiation in the low MeV range (E = 15 MeV)

International Nuclear Information System (INIS)

Do, N.-L.

2012-01-01

We have shown that argon ion irradiation between 1 and 15 MeV produces damage on both titanium and zirconium surfaces, taking the form of accelerated oxidation and/or craterization effects, varying as a function of the projectile energy and the annealing atmosphere (temperature and pressure) simulating the environmental conditions of the fuel/cladding interface of PWR fuel rods. Using AFM, we have shown that the titanium and zirconium surface is attacked under light argon ion bombardment at high temperature (up to 500 C) in weakly oxidizing medium (under rarefied dry air pressure ranging from 5,7 10 -5 Pa to 5 10 -3 Pa) for a fixed fluence of about 5 10 14 ions.cm -2 . We observed the formation of nano-metric craters over the whole titanium surface irradiated between 2 and 9 MeV and the whole zirconium surface irradiated at 4 MeV, the characteristics of which vary depending on the temperature and the pressure. In the case of the Ar/Ti couple, the superficial damage efficiency increases when the projectile energy decreases from 9 to 2 MeV. Moreover, whereas the titanium surface seems to be transparent under the 15-MeV ion beam, the zirconium surface exhibits numerous micrometric craters surrounded by a wide halo. The crater characteristics (size and superficial density) differ significantly from that observed both in the low energy range (keV) where the energy losses are controlled by ballistic collisions (Sn) and in the high energy range (MeV - GeV) where the energy losses are controlled by electronic excitations (Se), which was not completely unexpected in this intermediate energy range for which combined Sn - Se stopping power effects are possibly foreseen. Using XPS associated to ionic sputtering, we have shown that there is an irradiation effect on thermal oxidation of titanium, enhanced under the argon ion beam between 2 and 9 MeV, and that there is also an energy effect on the oxide thickness and stoichiometry. The study conducted using Spectroscopic

Conceptual design of the Argonne 6-GeV synchrotron light source

International Nuclear Information System (INIS)

Cho, Y.; Crosbie, E.; Khoe, T.

1985-01-01

The Argonne National Laboratory Synchrotron Light Source Storage Ring is designed to have a natural emittance of 6.5 X 10 -9 m for circulating 6-GeV positrons. Thirty of the 32 long straight sections, each 6.5-m long, will be available for synchrotron light insertion devices. A circulating positron current of 300 mA can be injected in about 8 min. from a booster synchrotron operating with a repetition time of 1.2 sec. The booster synchrotron will contain two different rf systems. The lower frequency system (38.97 MHz) will accept positrons from a 360-MeV linac and will accelerate them to 2.25 GeV. The higher frequency system (350.76 MHz) will accelerate the positrons to 6 GeV. The positrons will be produced from a 300-MeV electron beam on a tungsten target

FERMI LAT OBSERVATIONS OF LS I +610303: FIRST DETECTION OF AN ORBITAL MODULATION IN GeV GAMMA RAYS

International Nuclear Information System (INIS)

Abdo, A. A.; Ackermann, M.; Ajello, M.; Bechtol, K.; Berenji, B.; Blandford, R.; Bloom, E. D.; Borgland, A. W.; Atwood, W. B.; Axelsson, M.; Baldini, L.; Bellazzini, R.; Bregeon, J.; Brez, A.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Baughman, B. M.; Bonamente, E.; Brigida, M.

2009-01-01

This Letter presents the first results from the observations of LS I +61 0 303 using Large Area Telescope data from the Fermi Gamma-Ray Space Telescope between 2008 August and 2009 March. Our results indicate variability that is consistent with the binary period, with the emission being modulated at 26.6 ± 0.5 days. This constitutes the first detection of orbital periodicity in high-energy gamma rays (20 MeV-100 GeV, HE). The light curve is characterized by a broad peak after periastron, as well as a smaller peak just before apastron. The spectrum is best represented by a power law with an exponential cutoff, yielding an overall flux above 100 MeV of 0.82 ± 0.03(stat) ± 0.07(syst) 10 -6 ph cm -2 s -1 , with a cutoff at 6.3 ± 1.1(stat) ± 0.4(syst) GeV and photon index Γ = 2.21 ± 0.04(stat) ± 0.06(syst). There is no significant spectral change with orbital phase. The phase of maximum emission, close to periastron, hints at inverse Compton scattering as the main radiation mechanism. However, previous very high-energy gamma ray (>100 GeV, VHE) observations by MAGIC and VERITAS show peak emission close to apastron. This and the energy cutoff seen with Fermi suggest that the link between HE and VHE gamma rays is nontrivial.

Search for sleptons in $e^+ e^-$ collisions at centre-of-mass energies of 161 GeV and 172 GeV

CERN Document Server

Barate, R; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Nief, J Y; Pietrzyk, B; Casado, M P; Chmeissani, M; Comas, P; Crespo, J M; Delfino, M C; Fernández, E; Fernández-Bosman, M; Garrido, L; Juste, A; Martínez, M; Miquel, R; Mir, L M; Orteu, S; Padilla, C; Park, I C; Pascual, A; Perlas, J A; Riu, I; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Gelao, G; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Abbaneo, D; Alemany, R; Bazarko, A O; Becker, U; Bright-Thomas, P G; Cattaneo, M; Cerutti, F; Dissertori, G; Drevermann, H; Forty, Roger W; Frank, M; Hagelberg, R; Hansen, J B; Harvey, J; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Lutters, G; Mato, P; Minten, Adolf G; Moneta, L; Pacheco, A; Pusztaszeri, J F; Ranjard, F; Rizzo, G; Rolandi, Luigi; Rousseau, D; Schlatter, W D; Schmitt, M; Schneider, O; Tejessy, W; Tomalin, I R; Wachsmuth, H W; Wagner, A; Ajaltouni, Ziad J; Barrès, A; Boyer, C; Falvard, A; Ferdi, C; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rosnet, P; Rossignol, J M; Fearnley, Tom; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Daskalakis, G; Kyriakis, A; Markou, C; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Blondel, A; Brient, J C; Machefert, F P; Rougé, A; Rumpf, M; Valassi, Andrea; Videau, H L; Focardi, E; Parrini, G; Zachariadou, K; Cavanaugh, R J; Corden, M; Georgiopoulos, C H; Hühn, T; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Casper, David William; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Curtis, L; Dorris, S J; Halley, A W; Knowles, I G; Lynch, J G; O'Shea, V; Raine, C; Scarr, J M; Smith, K; Teixeira-Dias, P; Thompson, A S; Thomson, E; Thomson, F; Turnbull, R M; Geweniger, C; Graefe, G; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Schmidt, M; Sommer, J; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Girone, M; Goodsir, S M; Martin, E B; Morawitz, P; Moutoussi, A; Nash, J; Sedgbeer, J K; Spagnolo, P; Stacey, A M; Williams, M D; Ghete, V M; Girtler, P; Kuhn, D; Rudolph, G; Betteridge, A P; Bowdery, C K; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Jones, R W L; Sloan, Terence; Whelan, E P; Williams, M I; Hoffmann, C; Jakobs, K; Kleinknecht, K; Quast, G; Renk, B; Rohne, E; Sander, H G; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Coyle, P; Diaconu, C A; Konstantinidis, N P; Leroy, O; Motsch, F; Payre, P; Talby, M; Sadouki, A; Thulasidas, M; Tilquin, A; Trabelsi, K; Aleppo, M; Ragusa, F; Berlich, R; Blum, Walter; Büscher, V; Dietl, H; Ganis, G; Gotzhein, C; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Stenzel, H; Wiedenmann, W; Wolf, G; Boucrot, J; Callot, O; Chen, S; Cordier, A; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Höcker, A; Jacholkowska, A; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Nikolic, I A; Schune, M H; Serin, L; Simion, S; Tournefier, E; Veillet, J J; Videau, I; Zerwas, D; Azzurri, P; Bagliesi, G; Bettarini, S; Bozzi, C; Calderini, G; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Giassi, A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Sanguinetti, G; Sciabà, A; Steinberger, Jack; Tenchini, Roberto; Vannini, C; Venturi, A; Verdini, P G; Blair, G A; Bryant, L M; Chambers, J T; Gao, Y; Green, M G; Medcalf, T; Perrodo, P; Strong, J A; Von Wimmersperg-Töller, J H; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Maley, P; Norton, P R; Thompson, J C; Wright, A E; Bloch-Devaux, B; Colas, P; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Pérez, P; Rander, J; Renardy, J F; Rosowsky, A; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Black, S N; Dann, J H; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Boswell, R; Brew, C A J; Cartwright, S L; Combley, F; Kelly, M S; Lehto, M H; Newton, W M; Reeve, J; Thompson, L F; Affholderbach, K; Böhrer, A; Brandt, S; Cowan, G D; Foss, J; Grupen, Claus; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Musolino, G; Pütz, J; Rothberg, J E; Wasserbaech, S R; Williams, R W; Armstrong, S R; Charles, E; Elmer, P; Ferguson, D P S; González, S; Greening, T C; Hayes, O J; Hu, H; Jin, S; McNamara, P A; Nachtman, J M; Nielsen, J; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Walsh, J; Wu Sau Lan; Wu, X; Yamartino, J M; Zobernig, G

1997-01-01

The data recorded by the ALEPH experiment at LEP at centre-of-mass energies of 161 GeV and 172 GeV were analysed to search for sleptons, the supersymmetric partners of leptons. No evidence for the production of these particles was found. The number of candidates observed is consistent with the background expected from four-fermion processes and gammagamma-interactions. Improved mass limits at 95% C.L. are reported.

Search for sleptons in e+e- collisions at centre-of-mass energies of 161 GeV and 172 GeV

Science.gov (United States)

Barate, R.; Buskulic, D.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Lucotte, A.; Minard, M.-N.; Nief, J.-Y.; Pietrzyk, B.; Casado, M. P.; Chmeissani, M.; Comas, P.; Crespo, J. M.; Delfino, M.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, Ll.; Juste, A.; Martinez, M.; Miquel, R.; Mir, Ll. M.; Orteu, S.; Padilla, C.; Park, I. C.; Pascual, A.; Perlas, J. A.; Riu, I.; Sanchez, F.; Teubert, F.; Colaleo, A.; Creanza, D.; de Palma, M.; Gelao, G.; Iaselli, G.; Maggi, G.; Maggi, M.; Marinelli, N.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Alemany, R.; Bazarko, A. O.; Becker, U.; Bright-Thomas, P.; Cattaneo, M.; Cerutti, F.; Dissertori, G.; Drevermann, H.; Forty, R. W.; Frank, M.; Hagelberg, R.; Hansen, J. B.; Harvey, J.; Janot, P.; Jost, B.; Kneringer, E.; Knobloch, J.; Lehraus, I.; Lutters, G.; Mato, P.; Minten, A.; Moneta, L.; Pacheco, A.; Pusztaszeri, J.-F.; Ranjard, F.; Rizzo, G.; Rolandi, L.; Rousseau, D.; Schlatter, D.; Schmitt, M.; Schneider, O.; Tejessy, W.; Tomalin, I. R.; Wachsmuth, H.; Wagner, A.; Ajaltouni, Z.; Barrès, A.; Boyer, C.; Falvard, A.; Ferdi, C.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Rosnet, P.; Rossignol, J.-M.; Fearnley, T.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Nilsson, B. S.; Rensch, B.; Wäänänen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Vayaki, A.; Blondel, A.; Brient, J. C.; Machefert, F.; Rougé, A.; Rumpf, M.; Valassi, A.; Videau, H.; Focardi, E.; Parrini, G.; Zachariadou, K.; Cavanaugh, R.; Corden, M.; Georgiopoulos, C.; Huehn, T.; Jaffe, D. E.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Casper, D.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Dorris, S. J.; Halley, A. W.; Knowles, I. G.; Lynch, J. G.; O'Shea, V.; Raine, C.; Scarr, J. M.; Smith, K.; Teixeira-Dias, P.; Thompson, A. S.; Thomson, E.; Thomson, F.; Turnbull, R. M.; Geweniger, C.; Graefe, G.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E. E.; Putzer, A.; Schmidt, M.; Sommer, J.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Dornan, P. J.; Girone, M.; Goodsir, S.; Martin, E. B.; Morawitz, P.; Moutoussi, A.; Nash, J.; Sedgbeer, J. K.; Spagnolo, P.; Stacey, A. M.; Williams, M. D.; Ghete, V. M.; Girtler, P.; Kuhn, D.; Rudolph, G.; Betteridge, A. P.; Bowdery, C. K.; Colrain, P.; Crawford, G.; Finch, A. J.; Foster, F.; Hughes, G.; Jones, R. W.; Sloan, T.; Whelan, E. P.; Williams, M. I.; Hoffmann, C.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.-G.; van Gemmeren, P.; Zeitnitz, C.; Aubert, J. J.; Benchouk, C.; Bonissent, A.; Bujosa, G.; Calvet, D.; Carr, J.; Coyle, P.; Diaconu, C.; Konstantinidis, N.; Leroy, O.; Motsch, F.; Payre, P.; Talby, M.; Sadouki, A.; Thulasidas, M.; Tilquin, A.; Trabelsi, K.; Aleppo, M.; Ragusa, F.; Berlich, R.; Blum, W.; Büscher, V.; Dietl, H.; Ganis, G.; Gotzhein, C.; Kroha, H.; Lütjens, G.; Lutz, G.; Männer, W.; Moser, H.-G.; Richter, R.; Rosado-Schlosser, A.; Schael, S.; Settles, R.; Seywerd, H.; St. Denis, R.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Boucrot, J.; Callot, O.; Chen, S.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Höcker, A.; Jacholkowska, A.; Jacquet, M.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Nikolic, I.; Schune, M.-H.; Serin, L.; Simion, S.; Tournefier, E.; Veillet, J.-J.; Videau, I.; Zerwas, D.; Azzurri, P.; Bagliesi, G.; Bettarini, S.; Bozzi, C.; Calderini, G.; Ciulli, V.; dell'Orso, R.; Fantechi, R.; Ferrante, I.; Giassi, A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Sanguinetti, G.; Sciabà, A.; Steinberger, J.; Tenchini, R.; Vannini, C.; Venturi, A.; Verdini, P. G.; Blair, G. A.; Bryant, L. M.; Chambers, J. T.; Gao, Y.; Green, M. G.; Medcalf, T.; Perrodo, P.; Strong, J. A.; von Wimmersperg-Toeller, J. H.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Haywood, S.; Maley, P.; Norton, P. R.; Thompson, J. C.; Wright, A. E.; Bloch-Devaux, B.; Colas, P.; Fabbro, B.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.-F.; Rosowsky, A.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S. N.; Dann, J. H.; Kim, H. Y.; Litke, A. M.; McNeil, M. A.; Taylor, G.; Booth, C. N.; Boswell, R.; Brew, C. A. J.; Cartwright, S.; Combley, F.; Kelly, M. S.; Lehto, M.; Newton, W. M.; Reeve, J.; Thompson, L. F.; Affholderbach, K.; Böhrer, A.; Brandt, S.; Cowan, G.; Foss, J.; Grupen, C.; Saraiva, P.; Smolik, L.; Stephan, F.; Apollonio, M.; Bosisio, L.; della Marina, R.; Giannini, G.; Gobbo, B.; Musolino, G.; Putz, J.; Rothberg, J.; Wasserbaech, S.; Williams, R. W.; Armstrong, S. R.; Charles, E.; Elmer, P.; Ferguson, D. P. S.; González, S.; Greening, T. C.; Hayes, O. J.; Hu, H.; Jin, S.; McNamara, P. A.; Nachtman, J. M.; Nielsen, J.; Orejudos, W.; Pan, Y. B.; Saadi, Y.; Scott, I. J.; Walsh, J.; Sau, Lan Wu; Wu, X.; Yamartino, J. M.; Zobernig, G.

1997-02-01

The data recorded by the ALEPH experiment at LEP at centre-of-mass energies of 161 GeV and 172 GeV were analysed to search for sleptons, the supersymmetric partners of leptons. No evidence for the production of these particles was found. The number of candidates observed is consistent with the background expected from four-fermion processes and yy-interactions. Improved mass limits at 95% C.L. are reported.

Upgrade of the CERN Proton Synchrotron Booster bending magnets for 2 GeV Operation

CERN Document Server

Newborough, A; Chritin, R

2013-01-01

Since its first operation in 1972 at an energy of 800MeV the CERN Proton Synchrotron Booster, which consists of 4 super imposed synchrotrons, has seen two upgrades: once to 1.0 GeV in 1988 and then to 1.4 GeV in 1999. During this time the main magnets of the machine have remained largely unchanged with small differences (<1%) between the inner and outer gaps of the main bending magnet fields being compensated by trim power supplies. The future upgrade of the machine will demand to extract protons at an energy of 2.0 GeV and require almost double the original dipole field. At this field, due to saturation effects, the inner and outer gaps of the main dipole magnets will differ by up to 4%. This paper presents the design and implementation of a modification of the magnetic circuit strongly reducing these effects. We also discuss the results of experimental tests concerning the effects on field quality and eddy current transients, including the implications for the real-time magnetic field measurement system ...

Neutron production from 40 GeV/c mixed proton/pion beam on copper, silver and lead targets in the angular range 30-135 degree

CERN Document Server

Agosteo, S; Dimovasili, E; Foglio-Para, A; Silari, M; Ulrici, L; Vincke, H

2005-01-01

The neutron emission from 50 mm thick copper, silver and lead targets bombarded by a mixed proton/pion beam with momentum of 40 GeV/c were measured at the CERN Super Proton Synchrotron. The neutron yield and spectral fluence per incident particle on target were measured with an extended range Bonner sphere spectrometer in the angular range 30-135 degree with respect to the beam direction. Monte Carlo simulations with the FLUKA code were performed to provide a priori information for the unfolding of the experimental data. The spectral fluences show two peaks, an isotropic evaporation component centred at 3 MeV and a high-energy peak sitting around 100-150 MeV. The experimental neutron yields are given in four energy bins: less than 100 keV, 0.1-20 MeV, 20-500 MeV and 0.5-2 GeV. The total yields show a systematic discrepancy of 30-50%, with a peak of 70% at the largest angles, with respect to the results of the Monte Carlo simulations, which it is believed to be mainly due to uncertainties in the beam normaliza...

Average fast neutron flux in three energy ranges in the Quinta assembly irradiated by two types of beams

Directory of Open Access Journals (Sweden)

Strugalska-Gola Elzbieta

2017-01-01

Full Text Available This work was performed within the international project “Energy plus Transmutation of Radioactive Wastes” (E&T - RAW for investigations of energy production and transmutation of radioactive waste of the nuclear power industry. 89Y (Yttrium 89 samples were located in the Quinta assembly in order to measure an average high neutron flux density in three different energy ranges using deuteron and proton beams from Dubna accelerators. Our analysis showed that the neutron density flux for the neutron energy range 20.8 - 32.7 MeV is higher than for the neutron energy range 11.5 - 20.8 MeV both for protons with an energy of 0.66 GeV and deuterons with an energy of 2 GeV, while for deuteron beams of 4 and 6 GeV we did not observe this.

An alternative explanation for the GeV excess in the Fermi gamma ray data

Energy Technology Data Exchange (ETDEWEB)

Gebauer, Iris; Boer, Wim de; Neumann, Alexander [Karlsruhe Institute of Technologie, Karlsruhe (Germany)

2016-07-01

Towards the Galactic center the diffuse Fermi Gamma Ray data show a 1-3 GeV excess, which has been interpreted previously as a new source, like dark matter annihilation, contributions from millisecond pulsars or cosmic rays interacting with molecular clouds. We search for this excess in the whole Galactic Plane and find it to be perfectly correlated with the spatial distribution of the {sup 26}Al line, thought to be a tracer of SNRs. So the excess is not only found in the Galactic Center, but found everywhere, where there are molecular clouds (MCs). This excludes the dark matter annihilation interpretation. If we assume the proton spectrum in MCs to be depleted at energies below 14 GeV by a combination of trapping, solar winds and energy losses, we find a perfect description of the whole gamma ray sky. In this case the excess is not an excess, but a depletion of low energy gamma rays below a few GeV due to the depletion of the protons in MCs below 14 GeV, which happens not only in the Galactic Center, but everywhere in the Galactic Plane, where there are MCs with star formation, as proven by the identical morphology of the excess and the 1.8 MeV line of {sup 26}Al, observed by Comptel and Integral.

Investigation of the effective atomic numbers of dosimetric materials for electrons, protons and alpha particles using a direct method in the energy region 10 keV-1 GeV: a comparative study.

Science.gov (United States)

Kurudirek, Murat; Aksakal, Oğuz; Akkuş, Tuba

2015-11-01

A direct method has been used for the first time, to compute effective atomic numbers (Z eff) of water, air, human tissues, and some organic and inorganic compounds, for total electron proton and alpha particle interaction in the energy region 10 keV-1 GeV. The obtained values for Z eff were then compared to those obtained using an interpolation procedure. In general, good agreement has been observed for electrons, and the difference (%) in Z eff between the results of the direct and the interpolation method was found to be energy range from 10 keV to 1 MeV. More specifically, results of the two methods were found to agree well (Dif. energy region with respect to the total electron interaction. On the other hand, values for Z eff calculated using both methods for protons and alpha particles generally agree with each other in the high-energy region above 10 MeV.

A study of LPM suppression of bremsstrahlung at 25 GeV

International Nuclear Information System (INIS)

Anthony, P.; Becker-Szendy, R.; Bosted, P.

1993-03-01

We are making an accurate measurement of the LPM suppression of bremsstrahlung with 25 GeV electrons. By using a 120 pulses per second beam, a precise BGO calorimeter, and spectrometer to tag the outgoing electrons, we are able to make an accurate measurement of the bremsstrahlung photons in the 0-400 MeV region, where the Bethe Heitler and LPM predictions differ. We are taking data with targets made of carbon, uranium, tungsten and iron, with thicknesses in the 2% to 6% X 0 range. In addition, we are taking data with two very thin gold targets. The latter have thicknesses that are comparable to or less than the LPM formation zone length, and so should not exhibit LPM suppression. We are also studying photons of a few MeV in energy, to test the closely related longitudinal density effect predicted by Ter-Mikaelian in which very low energy photon emission is suppressed due to dielectric effects of the medium

Differential cross section measurements of the π-p elastic scattering in the Coulomb interference region between 30 and 140 GeV

International Nuclear Information System (INIS)

Ille, B.

1979-01-01

The differential cross section of elastic π - -p scattering in the Coulomb interference region from 30 GeV to 140 GeV has been measured at the CERN SPS using in conjunction an ionization chamber recoil spectrometer and a forward multiwire proportional chamber-magnet spectrometer. The phase of the π - -p forward hadronic amplitude was found to go four negative value (at 30 GeV) to positive value (at 140 GeV), passing through zero at about 60 GeV. The logarithmic slope at small /t/ (/t/ approximately 0.03 (GeV/c) 2 ) has also been measured and was found to be higher by about 3 (GeV/c) -2 than the values determined at higher /t/ (/t/ = 0.2 (GeV/c) 2 ) [fr

INC Model interpretation of the proton induced residual nuclide production cross sections below 2 GeV

International Nuclear Information System (INIS)

Divadeenam, M.; Ward, T.E.; Spergel, M.S.; Lakatos, S.; Manche, E.P.

1991-01-01

For the purposes of interpreting the abundances of various isotopes in meteorites or on lunar and planetary surfaces exposed to fragmentation by cosmic rays, Webber et al. recently reported the measured total elemental and isotopic cross sections with heavy ions as projectiles on H, He, and C targets with beam energies of 0.33 - 1.7 GeV/nucleon. We employ the INC model to predict the fragmentation of the heavy ions in a hydrogen target with the inverse reaction process: proton bombardment of a heavy-ion nucleus leading to spallation products. Charge-changing and mass-changing cross sections are calculated for proton bombardment of an 56 Fe target with beam energies ranging from 0.33 to 1.88 GeV. Total Z-changing and A-changing cross sections in the energy range 0.6 to 1.88 GeV are in excellent agreement with the corresponding experimental data of Webber et al. and Westfall at al., while the agreement below 0.6 GeV proton energy is not as good. The general trend of the Z-changing cross sections are reproduced by the model calculations at each proton incident energy. The interaction of 200-MeV protons with synthetic Stony Meteorite samples was undertaken to explain radionuclide production in a cosmic-ray environment. The BNL Linac 200-MeV-proton beam was used to irradiate synthetic Stony Meteorites to simulate cosmic-ray exposures corresponding to 6.4 and 16.4 million years. Each irradiated sample was analyzed with the help of a high-resolution gamma-ray spectrometer for long-lived radioisotopes. The intranuclear cascade code HETC was employed to simulate the 200-MeV proton bombardment on the meteorite samples to predict the radionuclides 7 Be, 22 Na, 46 Mn, and 56 Co produced in the experimental investigation

Radiation protection studies for a high-power 160 MeV proton linac

CERN Document Server

Mauro, Egidio

2009-01-01

CERN is presently designing a new chain of accelerators to replace the present Proton Synchrotron (PS) complex: a 160 MeV room-temperature H− linac (Linac4) to replace the present 50 MeV proton linac injector, a 3.5 GeV Superconducting Proton Linac (SPL) to replace the 1.4 GeV PS Booster (PSB) and a 50 GeV synchrotron (named PS2) to replace the 26 GeV PS. Linac4 has been funded and the civil engineering work started in October 2008, whilst the SPL is in an advanced stage of design. Beyond injecting into the future 50 GeV PS, the ultimate goal of the SPL is to generate a 4 MW beam for the production of intense neutrino beams. The radiation protection design is driven by the latter requirement. This work summarizes the radiation protection studies conducted for Linac4. FLUKA Monte Carlo simulations, complemented by analytical estimates, were performed to evaluate the propagation of neutrons through the waveguide, ventilation and cable ducts placed along the accelerator, to estimate the radiological impact of ...

Conceptual design of the Argonne 6-GeV synchrotron light source

International Nuclear Information System (INIS)

Cho, Y.; Crosbie, E.; Khoe, T.

1985-01-01

The Argonne National Laboratory Synchrotron Light Source Storage Ring is designed to have a natural emittance of 6.5 x 10 -9 m for circulating 6-GeV positrons. Thirty of the 32 long straight sections, each 6.5-m long, will be available for synchrotron light insertion devices. A circulating positron current of 300 mA can be injected in about 8 min. from a booster synchrotron operating with a repetition time of 1.2 sec. The booster synchrotron will contain two different RF systems. The lower frequency system (38.97 MHz) will accept positrons from a 360-MeV linac and will accelerate them to 2.25 GeV. The higher frequency system (350.76 MHz) will accelerate the positrons to 6 GeV. The positrons will be produced from a 300-MeV electron beam on a tungsten target. A conceptual layout is shown

Energy monitoring device for 1.5-2.4 MeV electron beams

Energy Technology Data Exchange (ETDEWEB)

Fuochi, P.G., E-mail: fuochi@isof.cnr.i [CNR-ISOF, Via P. Gobetti 101, I-40129 Bologna (Italy); Lavalle, M.; Martelli, A. [CNR-ISOF, Via P. Gobetti 101, I-40129 Bologna (Italy); Kovacs, A. [Institute of Isotopes, HAS, P.O.Box 77, H-1525 Budapest (Hungary); Mehta, K. [Arbeiterstrandbad Strasse 72, Vienna, A-1210 (Austria); Kuntz, F.; Plumeri, S. [Aerial, Parc d' Innovation Rue Laurent Fries F-67400 Illkirch (France)

2010-03-11

An easy-to-use and robust energy monitoring device has been developed for reliable detection of day-to-day small variations in the electron beam energy, a critical parameter for quality control and quality assurance in industrial radiation processing. It has potential for using on-line, thus providing real-time information. Its working principle is based on the measurement of currents, or charges, collected by two aluminium absorbers of specific thicknesses (dependent on the beam energy), insulated from each other and positioned within a faraday cup-style aluminium cage connected to the ground. The device has been extensively tested in the energy range of 4-12 MeV under standard laboratory conditions at Institute of Isotopes and CNR-ISOF using different types of electron accelerators; namely, a TESLA LPR-4 LINAC (3-6 MeV) and a L-band Vickers LINAC (7-12 MeV), respectively. This device has been also tested in high power electron beam radiation processing facilities, one equipped with a 7-MeV LUE-8 linear accelerator used for crosslinking of cables and medical device sterilization, and the other equipped with a 10 MeV Rhodotron TT100 recirculating accelerator used for in-house sterilization of medical devices. In the present work, we have extended the application of this method to still lower energy region, i.e. from 1.5 to 2.4 MeV. Also, we show that such a device is capable of detecting deviation in the beam energy as small as 40 keV.

Energy monitoring device for 1.5-2.4 MeV electron beams

Science.gov (United States)

Fuochi, P. G.; Lavalle, M.; Martelli, A.; Kovács, A.; Mehta, K.; Kuntz, F.; Plumeri, S.

2010-03-01

An easy-to-use and robust energy monitoring device has been developed for reliable detection of day-to-day small variations in the electron beam energy, a critical parameter for quality control and quality assurance in industrial radiation processing. It has potential for using on-line, thus providing real-time information. Its working principle is based on the measurement of currents, or charges, collected by two aluminium absorbers of specific thicknesses (dependent on the beam energy), insulated from each other and positioned within a faraday cup-style aluminium cage connected to the ground. The device has been extensively tested in the energy range of 4-12 MeV under standard laboratory conditions at Institute of Isotopes and CNR-ISOF using different types of electron accelerators; namely, a TESLA LPR-4 LINAC (3-6 MeV) and a L-band Vickers LINAC (7-12 MeV), respectively. This device has been also tested in high power electron beam radiation processing facilities, one equipped with a 7-MeV LUE-8 linear accelerator used for crosslinking of cables and medical device sterilization, and the other equipped with a 10 MeV Rhodotron TT100 recirculating accelerator used for in-house sterilization of medical devices. In the present work, we have extended the application of this method to still lower energy region, i.e. from 1.5 to 2.4 MeV. Also, we show that such a device is capable of detecting deviation in the beam energy as small as 40 keV.

200-MeV bremsstrahlung tagged photon beams at Sendai

International Nuclear Information System (INIS)

Hirose, K.; Chiba, M.; Inoue, M.; Kanda, H.; Kimura, R.; Kino, K.; Kobayashi, Y.; Konno, O.; Maeda, K.; Miyase, H.; Miyamoto, A.; Ohtsuki, T.; Saito, A.; Suda, T.; Takahashi, K.; Tamae, T.; Terasaki, Y.; Terasawa, T.; Tsubota, H.; Tsuruta, T.; Utoyama, M.; Yuuki, H.; Yamaguchi, Y.; Yamazaki, H.

2006-01-01

A new beam line for photonuclear reaction experiments using tagged photons has been constructed to take advantage of the completion of the 1.2-GeV STretcher Booster (STB) ring at the Laboratory of Nuclear Science (LNS), Tohoku University. A photon tagging system was installed at the end of the new beam line. It provides bremsstrahlung tagged photon beams in an energy range from 0.2E 0 to 0.8E 0 MeV at the incident electron energy E 0 with an energy resolution of ΔE/E∼10 -2 . The tagged photon intensity I= 6 photons/s is available for typical photonuclear reaction experiments. We introduce the basic parameters of the tagged photons by showing the commissioning data

Spectra of the linear energy transfer measured with a track etch spectrometer in the beam of 1 GeV protons and the contribution of secondary charged particles to the dose

International Nuclear Information System (INIS)

Spurny, F.; Vlcek, B.; Bamblevskij, V.P.; Timoshenko, G.N.

1999-01-01

A spectrometer of the linear energy transfer (LET) on the base of CR-39 detector was used to establish the spectra of LET in the beam of protons with the primary energy of 1 GeV. It was found out that the LET spectra of secondary charged particles between 100 and 7000 MeV cm 2 g -1 do not depend on the radiator. The average quality factors for the LET region mentioned were obtained about 11.6 with ICRP 26 quality factors and about 14.0 with ICRP 60 quality factors. The spectra obtained permitted to calculate the contributions of these secondary charged particles to the dosimetric quantities. It was observed that these contributions were about 7.0% for the total absorbed dose of protons and close 90% in the case of the equivalent doses. It is more than it was found out for few hundred MeV protons

Medium energy high intensity proton accelerator (MEHIPA): Reference Design Report (RDR) Ver. 1.0

International Nuclear Information System (INIS)

2016-11-01

Recent progress in accelerator technology has made it possible to use a proton accelerator to produce nuclear energy. In an accelerator-driven system (ADS), a high-intensity proton accelerator is used to produce protons of around 1 GeV energy, which strike a target such as lead or tungsten to produce spallation neutrons. ADS can be used to produce power, incinerate minor actinides and long-lived fission products, and for the utilization of thorium as an alternative nuclear fuel. The accelerator for ADS has to produce high energy (1 GeV) protons, and deliver tens of milli amperes of beam current with minimum (< 1 nA/m) beam loss for hands-on maintenance of the accelerator. This makes the development of accelerators for ADS very challenging. In India, it is planned to take a staged approach towards development of the requisite accelerator technology, and it is planned to develop the accelerator in three phases: 20 MeV, 200 MeV and 1 GeV. This report presents a reference design report for the Medium Energy High Intensity Proton Accelerator (MEHIPA) which will accelerate the beam to 200 MeV. The linac consists of a 3 MeV normal conducting RFQ followed by three families of superconducting Single Spoke Resonators (SSR) to accelerate the beam to 200 MeV. The major elements of the physics design of MEHIPA, as well as layouts and specifications of the major accelerator sub-systems are presented in this report. (author)

Extension of the calibration of an NE-213 liquid scintillator based pulse height response spectrometer up to 18 MeV neutron energy and leakage spectrum measurements on bismuth at 8 MeV and 18 MeV neutron energies

International Nuclear Information System (INIS)

Fenyvesi, A.; Valastyan, I.; Olah, L.; Csikai, J.; Plompen, A.; Jaime, R.; Loevestam, G.; Semkova, V.

2011-01-01

Monoenergetic neutrons were produced at the Van de Graaff accelerator of the EC-JRC-Institute for Reference Materials and Measurements (IRMM, Geel, Belgium). An air-jet cooled D_2-gas target (1.2 bar, ΔE_d = 448 keV) was bombarded with E_d =4976 keV deuterons to produce neutrons up to E_n = 8 MeV energy via the D(d,n)"3He reaction. Higher energy neutrons up to E_n = 18 MeV were produced via the T(d,n)"4He reaction by bombarding a TiT target with E_d =1968 keV deuterons. Pulse height spectra were measured at different neutron energies from E_n = 8 MeV up to E_n = 18 MeV with the NE-213 liquid scintillator based Pulse Height Response Spectrometer (PHRS) of UD-IEP. The energy calibration of the PHRS system has been extended up to E_n = 18 MeV. Pulse height spectra induced by gamma photons have been simulated by the GRESP7 code. Neutron induced pulse height spectra have been simulated by the NRESP7 and MCNP-POLIMI codes. Comparison of the results of measurements and simulations enables the improvement of the parameter set of the function used by us to describe the light output dependence of the resolution of the PHRS system at light outputs of L > 2 light units. Also, it has been shown that the derivation method for unfolding neutron spectra from measured pulse height spectra performs well when relative measurements are done up to E_n = 18 MeV neutron energy. For matrix unfolding purposes, the NRESP7 code has to be preferred to calculate the pulse height response matrix of the PHRS system. Leakage spectra of neutrons behind bismuth slabs of different thicknesses have been measured with the PHRS system by using monoenergetic neutrons. The maximum slab thickness was d = 14 cm. Simulations of the measurements have been carried out with the MCNP-4c code. The necessary nuclear cross-sections were taken from the from the ENDF/B-VII and JEFF.3.1 data libraries. For both libraries, the agreement of measured and simulated neutron spectra is good for the 5 MeV ≤ En ≤ 18 MeV

The behavior of the Tevatron at energies greater than 1000 GeV

International Nuclear Information System (INIS)

Pogorelko, O.

1991-04-01

If, as appears likely, the top quark lies at the upper range of the mass reach of the Tevatron, then increasing the energy of the collider operation could prove to be a crucial factor in the future program together with projected luminosity enhancements. While a significant amount of data exists on individual magnets up to an energy of 1000 GeV, there are no detailed measurements above this value. We focus on the operating range beyond 1000 GeV in an attempt to see whether there is any realistic opportunity to extend the energy range of the Tevatron into this regime. The proposed modifications to the Tevatron Cryogenic System will provide sufficient cooling to lower the operating temperature of the 1000 superconducting magnets from the present 4.6--4.8K (1-φ inlet temperature) down to a range of 3.6--3.8K. At this temperature the short sample quench current for the dipole magnets should increase from the present value of ∼4000A (900 GeV) up to a level approaching 4800A (1100 GeV.) Increasing the peak current in the dipoles produces some important questions related to possible mechanical effects including catastrophic failure, the change of magnetic field quality, and quench protection problems resulting from the increased stored energy. In this note we shall examine these effects and comment on the existing data on low temperature operation. We have only considered the dipole magnets since the quadrupoles should not limit performance. We have not looked at the interaction region magnets which involve different considerations

Can annihilating dark matter be lighter than a few GeVs?

International Nuclear Information System (INIS)

Boehm, C; Ensslin, T A; Silk, J

2004-01-01

We estimate the gamma-ray fluxes from the residual annihilations of dark matter (DM) particles having a mass m dm from [MeV, O(10) GeV] (a possible solution to the DM issue provided they have a new kind of interactions and no significant coupling to the Z) and compare them to observations. We find that particles lighter than O(100 MeV) can be viable DM candidates provided their dominant annihilation cross section is S-wave suppressed so as to satisfy the gamma-ray constraints. A similar conclusion is obtained for particles lighter than O(10) GeV from the study of radio fluxes, assuming a NFW profile and that they mainly annihilate into electrons

Double-differential beryllium neutron cross sections at incident neutron energies of 5. 9, 10. 1, and 14. 2 MeV. [5. 9 to 14. 2 MeV, differential cross sections, ENDF/B-IV

Energy Technology Data Exchange (ETDEWEB)

Drake, D.M.; Auchampaugh, G.F.; Arthur, E.D.; Ragan, C.E.; Young, P.G.

1976-08-01

Beryllium neutron-production cross sections were measured using the time-of-flight technique at incident neutron energies of 5.9, 10.1, and 14.2 MeV, and at laboratory angles of 25, 27.5, 30, 35, 45, 60, 80, 100, 110, 125, and 145/sup 0/. The differential elastic and inelastic cross sections are presented. Inelastic is defined here as those reactions that proceed through the states at 1.69-, 2.43-, 2.8-, and 3.06-MeV excitation energy in /sup 9/Be. Comparison of emission energy spectra with calculations using the ENDF/B-IV beryllium cross sections shows that the ENDF/B cross sections strongly overemphasize the low lying states in /sup 9/Be.

Scattering of 30 MeV He3 from Re185

Science.gov (United States)

Garrett, P. E.; Phillips, A. A.; Demand, G. A.; Finlay, P.; Green, K. L.; Leach, K. G.; Schumaker, M. A.; Svensson, C. E.; Wong, J.; Hertenberger, R.; Wirth, H.-F.; Faestermann, T.; Krücken, R.; Burke, D. G.; Bettermann, L.; Braun, N.

2009-01-01

The scattering of 30 MeV He3 from a Re185 target has been investigated. The measured elastic scattering is in disagreement with calculations using common optical model parameter sets found in the literature. A new optical model parameter set has been determined that reproduces the data for both the elastic and the inelastic scattering channels.

Low-energy neutron measurements in an iron calorimeter structure irradiated by 200 GeV/c hadrons

Energy Technology Data Exchange (ETDEWEB)

Russ, J S [Carnegie-Mellon University, Pittsburgh, PA (United States); Stevenson, G R; Fasso, A; Nielsen, M C [CERN, Geneva (Switzerland); Furetta, C; Rancoita, P G; Vismara, I [INFN, Milan (Italy)

1989-04-21

Of serious concern in the design of detectors for the new high-luminosity hadron-hadron colliders are the radiation damage effects on silicon and other detectors of low-energy neutrons produced by spallation evaporation or fission processes. Because of the lack of experimental information on the number of neutrons with energies between 0.1 and 10 MeV in the cascades originating from high-energy hadrons, an experiment was carried out using activation detector techniques to measure the neutron fluence in a cascade initiated by 200 GeV hadrons in acalorimeter-like iron structure. It was found that at the maximum of the cascade one produces approximately 3 neutrons per GeV of incident energy: some 70% of these are of energies between 0.1 and 5 MeV, the remainder are fairly uniformly distributed in energy between 5 and several hundred MeV. The number of albedo neutrons leaving the front face of the calorimeter structure was about 0.3 neutrons per GeV of incident energy with in energy distribution similar to those at cascade maximum These data confirm that neutron-induced damage will he of concern in the design of detectors for the new colliders and that further measurements and calculations are necessary for a correct assessment of this damage. (author)

Momentum transfer with light ions at energies from 70 MeV to 1000 MeV

International Nuclear Information System (INIS)

Saint Laurent, F.; Conjeaud, M.; Dayras, R.; Harar, S.; Oeschler, H.; Volant, C.

1982-01-01

Angular correlations of fission fragments induced by bombarding a 232 Th target with protons, deuterons and alpha particles of energies from 70 MeV to 1000 MeV have been measured. They give information about the forward momentum imparted to the fissioning nuclei. We present the average values of the transferred linear momentum ([p vertical stroke vertical stroke ]) as a function of the incident energy and propose a classification into three regimes of dominating processes leading to fission: (I) low-energy behaviour, for E/A less than 10 MeV/u [p vertical stroke vertical stroke ]/psub(i) approx. equal to 1. (II) Between 10 MeV/u and about 70 MeV/u, [p vertical stroke vertical stroke ]/psub(i) decreases progressively down to 0.5 but remains proportional to the projectile mass. (III) The region between 70 MeV/u and about 1000 MeV/u corresponds to a transition region where the projectiles, whatever their masses, tend to transfer the same momentum. (orig.)

Measures of gamma rays between 0,3 MeV and 3,0 MeV and of the 0,511 MeV annihilation line coming from Galactic Center Region

International Nuclear Information System (INIS)

Jardim, M.V.A.

1982-04-01

The detection of the flux of the electron-positron annihilation line coming from the Galactic Center direction allows one to estimate the rate of positrons production and the corresponding luminosity. The results of measurements of the annihilation line flux intensity at 0.511 MeV, obtained with a balloon borne experiment to measure gamma rays in the energy interval 0.3 to 3 MeV are presented. The detector looked at the galactic disk in the longitude interval -31 0 0 and observed a flux intensity of (6.70 +- 0.85) x 10 -3 photons cm -2 s -1 , which is in good agreement with the flux value estimated assuming that the Galactic Center is a line source emitting uniformly. Some likely sources of positrons and annhilation regions are also discussed. The results for the continuum spectrum emitted from the Galactic Center in the energy interval 0.3 to 0.67 MeV are presented and compared with measurements had already made. (Author) [pt

Multiple collision effects on the antiproton production by high energy proton (100 GeV - 1000 GeV)

International Nuclear Information System (INIS)

Takahashi, Hiroshi; Powell, J.

1987-01-01

Antiproton production rates which take into account multiple collision are calculated using a simple model. Methods to reduce capture of the produced antiprotons by the target are discussed, including geometry of target and the use of a high intensity laser. Antiproton production increases substantially above 150 GeV proton incident energy. The yield increases almost linearly with incident energy, alleviating space charge problems in the high current accelerator that produces large amounts of antiprotons

Fission cross section measurements at the LLL 100-MeV linac

International Nuclear Information System (INIS)

Browne, J.C.

1975-01-01

The fission cross section for 235 U was measured from thermal energy to 20 MeV in several steps. First, the cross section was measured from 8 MeV to 20 MeV relative to the n,p scattering cross section and then from thermal to one MeV relative to 6 Li(n,α). In addition, a measurement of the ratio of the fission cross sections of 235 U and 238 U relative to 235 U has been completed in the range 1 keV to 30 MeV for 233 U and 100 keV to 30 MeV for 238 U. Statistical uncertainties are less than 4 percent. (U.S.)

A case for hidden b anti b tetraquarks based on e{sup +}e{sup -} {yields} b anti b cross sections between {radical}(s) = 10.54 and 11.20 GeV

Energy Technology Data Exchange (ETDEWEB)

Ali, Ahmed; Hambrock, Christian [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Ahmed, Ishtiaq [Quaid-i-Azam Univ., Islamabad (Pakistan). National Centre for Physics; Aslam, M. Jamil [Quaid-i-Azam Univ., Islamabad (Pakistan). Physics Dept.

2009-11-15

We study the spectroscopy and dominant decays of the bottomonium-like tetraquarks (bound diquarks-antidiquarks), focusing on the lowest lying P-wave [bq][anti b anti q] states Y{sub [bq]} (with q=u,d), having J{sup PC}=1{sup --}. To search for them, we analyse the BABAR data obtained during an energy scan of the e{sup +}e{sup -}{yields}b anti b cross section in the range of {radical}(s)=10.54 to 11.20 GeV. We find that these data are consistent with the presence of an additional b anti b state Y{sub [bq]} with a mass of 10.90 GeV and a width of about 30 MeV apart from the {upsilon}(5S) and {upsilon}(6S) resonances. A closeup of the energy region around the Y{sub [bq]}-mass may resolve this state in terms of the two mass eigenstates, Y{sub [b,l]} and Y{sub [b,h]}, with a mass difference, estimated as about 6 MeV. We tentatively identify the state Y{sub [bq]}(10900) from the R{sub b}-scan with the state Y{sub b}(10890) observed by BELLE in the process e{sup +}e{sup -}{yields}Y{sub b}(10890){yields}{upsilon}(1S,2S){pi}{sup +}{pi}{sup -} due to their proximity in masses and decay widths. (orig.)

Effective atomic numbers and electron densities of bacteriorhodopsin and its comprising amino acids in the energy range 1 keV–100 GeV

Energy Technology Data Exchange (ETDEWEB)

Ahmadi, Morteza; Lunscher, Nolan [Waterloo Institute for Nanotechnology and Department of Systems Design Engineering, University of Waterloo, 200 University Ave., W., Waterloo, Ontario, Canada N2L 3G1 (Canada); Yeow, John T.W., E-mail: jyeow@uwaterloo.ca [Waterloo Institute for Nanotechnology and Department of Systems Design Engineering, University of Waterloo, 200 University Ave., W., Waterloo, Ontario, Canada N2L 3G1 (Canada)

2013-04-01

Recently, there has been an interest in fabrication of X-ray sensors based on bacteriorhodopsin, a proton pump protein in cell membrane of Halobacterium salinarium. Therefore, a better understanding of interaction of X-ray photons with bacteriorhodopsin is required. We use WinXCom program to calculate the mass attenuation coefficient of bacteriorhodopsin and its comprising amino acids for photon energies from 1 keV to 100 GeV. These amino acids include alanine, arginine, asparagine, aspartic acid, glutamine, glutamic acid, glycine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, valine, Asx1, Asx2, Glx1 and Glx2. We then use that data to calculate effective atomic number and electron densities for the same range of energy. We also emphasize on two ranges of energies (10–200 keV and 1–20 MeV) in which X-ray imaging and radiotherapy machines work.

Beam dynamics studies of a 30 MeV RF linac for neutron production

Science.gov (United States)

Nayak, B.; Krishnagopal, S.; Acharya, S.

2018-02-01

Design of a 30 MeV, 10 Amp RF linac as neutron source has been carried out by means of ASTRA simulation code. Here we discuss details of design simulations for three different cases i.e Thermionic , DC and RF photocathode guns and compare them as injectors to a 30 MeV RF linac for n-ToF production. A detailed study on choice of input parameters of the beam from point of view of transmission efficiency and beam quality at the output have been described. We found that thermionic gun isn't suitable for this application. Both DC and RF photocathode gun can be used. RF photocathode gun would be of better performance.

Status of the GILDA project for the 30 MeV-100 GeV high energy gamma ray astrophysics

Energy Technology Data Exchange (ETDEWEB)

Casolino, M.; Sparvoli, R.; Morselli, A.; Picozza, P. [Rome Univ. `Tor Vergata` (Italy)]|[INFN, Rome (Italy); Barbiellini, G. [Trieste Univ. (Italy)]|[INFN, Trieste (Italy); Fuglesang, C. [ESA-EAC, Cologne (Germany); Ozerov, Yu.V.; Zemskov, V.M.; Zverev, V.G.; Galper, A.M. [Moscow Engineering Physics Institute, Moscow (Russian Federation)

1995-09-01

High energy gamma-ray astrophysics has greatly developed in the last few years because of the results of EGRET, on the Compton gamma ray observatory. The satellite observations have shown the importance of continuing the investigation of high energy gamma radiation but the emerging of new astrophysical and cosmological problems require for future experiments the realization of telescopes with parameters significatively improved with respect to the previous missions. In a traditional point of view, this is achieved with the increase of the length L of the device and, consequently, the mass of the telescope and satellite (growing as L{sup 3}). Such kinds of experiments are becoming rather expensive and are approaching the maximum value in cost, satellite mass and consuming resources. The telescope project GILDA presented in this paper is based on the use of silicon strip detectors. The silicon technique consents to obtain a much wider solid angle aperture; in this way there is more sensitivity without a growing in the size of the

Status of the GILDA project for the 30 MeV-100 GeV high energy gamma ray astrophysics

International Nuclear Information System (INIS)

Casolino, M.; Sparvoli, R.; Morselli, A.; Picozza, P.; Barbiellini, G.; Fuglesang, C.; Ozerov, Yu.V.; Zemskov, V.M.; Zverev, V.G.; Galper, A.M.

1995-01-01

High energy gamma-ray astrophysics has greatly developed in the last few years because of the results of EGRET, on the Compton gamma ray observatory. The satellite observations have shown the importance of continuing the investigation of high energy gamma radiation but the emerging of new astrophysical and cosmological problems require for future experiments the realization of telescopes with parameters significatively improved with respect to the previous missions. In a traditional point of view, this is achieved with the increase of the length L of the device and, consequently, the mass of the telescope and satellite (growing as L 3 ). Such kinds of experiments are becoming rather expensive and are approaching the maximum value in cost, satellite mass and consuming resources. The telescope project GILDA presented in this paper is based on the use of silicon strip detectors. The silicon technique consents to obtain a much wider solid angle aperture; in this way there is more sensitivity without a growing in the size of the

Quasi-monoenergetic neutron energy spectra for 246 and 389 MeV (7)Li(p,n) reactions at angles from 0 degrees to 300 degrees

CERN Document Server

Iwamoto, Y; Nakamura, T; Nakashima, H; Mares, V; Itoga, T; Matsumoto, T; Nakane, Y; Feldbaumer, E; Jaegerhofer, L; Pioch, C; Tamii, A; Satoh, D; Masuda, A; Sato, T; Iwase, H; Yashima, H; Nishiyama, J; Hagiwara, M; Hatanaka, K; Sakamoto, Y

2011-01-01

The authors measured the neutron energy spectra of a quasi-monoenergetic (7)Li(p,n) neutron source with 246 and 389 MeV protons set at seven angles (0 degrees, 2.5 degrees, 5 degrees, 10 degrees, 15 degrees, 20 degrees and 30 degrees), using a time-of-flight (TOF) method employing organic scintillators NE213 at the Research Center for Nuclear Physics (RCNP) of Osaka University. The energy spectra of the source neutrons were precisely deduced down to 2 MeV at 0 degrees and 10 MeV at other angles. The cross-sections of the peak neutron production reaction at 0 degrees were on the 35-40 mb line of other experimental data, and the peak neutron angular distribution agreed well with the Taddeucci formula. Neutron energy spectra below 100 MeV at all angles were comparable, but the shapes of the continuum above 150 MeV changed considerably with the angle. In order to consider the correction required to derive the response in the peak region from the measured total response for high-energy neutron monitors such as DAR...

Simulation of equivalent dose due to accidental electron beam loss in Indus-1 and Indus-2 synchrotron radiation sources using FLUKA code

International Nuclear Information System (INIS)

Sahani, P.K.; Dev, Vipin; Singh, Gurnam; Haridas, G.; Thakkar, K.K.; Sarkar, P.K.; Sharma, D.N.

2008-01-01

Indus-1 and Indus-2 are two Synchrotron radiation sources at Raja Ramanna Centre for Advanced Technology (RRCAT), India. Stored electron energy in Indus-1 and Indus-2 are 450MeV and 2.5GeV respectively. During operation of storage ring, accidental electron beam loss may occur in addition to normal beam losses. The Bremsstrahlung radiation produced due to the beam losses creates a major radiation hazard in these high energy electron accelerators. FLUKA, the Monte Carlo radiation transport code is used to simulate the accidental beam loss. The simulation was carried out to estimate the equivalent dose likely to be received by a trapped person closer to the storage ring. Depth dose profile in water phantom for 450MeV and 2.5GeV electron beam is generated, from which percentage energy absorbed in 30cm water phantom (analogous to human body) is calculated. The simulation showed the percentage energy deposition in the phantom is about 19% for 450MeV electron and 4.3% for 2.5GeV electron. The dose build up factor in 30cm water phantom for 450MeV and 2.5GeV electron beam are found to be 1.85 and 2.94 respectively. Based on the depth dose profile, dose equivalent index of 0.026Sv and 1.08Sv are likely to be received by the trapped person near the storage ring in Indus-1 and Indus-2 respectively. (author)

Some properties of the psi(3.7) resonance, and features of the total hadronic cross section in e+e- annihilation from 2.4 GeV to 5.0 GeV c.m. energy

International Nuclear Information System (INIS)

Kadyk, J.A.; Abrams, G.S.; Briggs, D.D.

1975-01-01

An analysis of data at the psi(3.7) resonance gives a partial width to electrons, MMA ub e/ = 2.2 +- 0.5 keV, and limits on total width 200 keV + π - is observed with a branching ratio 0.31 +- 0.04, and psi(3.7) → psi(3.1) + anything has a branching ratio of 0.54 +- 0.08. The psi resonances appear to have the same G-parity. An enhancement occurs in the total hadronic cross section at a c.m. energy of about 4.1 GeV, rising to about 32 nb from a level of 18 nb adjacent to peak, which is about 300 MeV wide. The integrated cross section for the peak is about 5.5 nb-GeV, comparable to that for the psi(3.7) and psi(3.1) resonances. (U.S.)

Some properties of the psi(3.7) resonance, and features of the total hadronic cross section in e+e- annihilation from 2.4GeV to 5.0GeV c.m. energy

International Nuclear Information System (INIS)

Abrams, G.S.; Briggs, D.D.; Chinowsky, W.; Friedberg, C.E.; Goldhaber, G.; Hollebeek, R.J.; Litke, A.; Lulu, B.A.; Pierre, F.; Sadoulet, B.; Trilling, G.H.; Whitaker, J.S.; Wiss, J.E.; Zipse, J.E.

1975-01-01

An analysis of data at the psi(3.7) resonance gives a partial width to electrons GAMMA(e)=2.2+-0.5keV, and limits on total width 200keV + π - is observed with a branching ratio 0.31+-0.04, and psi(3.7)→psi(3.1) + anything has a branching ratio of 0.54+-0.08. The psi resonances appear to have the same G-parity. An enhancement occurs in the total hadronic cross section at a c.m. energy of about 4.1GeV, rising to about 32nb from a level of 18nb adjacent to peak, which is about 300MeV wide. The integrated cross section for the peak is about 5.5nb-GeV, comparable to that for the psi(3.7) and psi(3.1) resonances

Neutron production from 40 GeV/c mixed proton/pion beam on copper, silver and lead targets in the angular range 30-135 deg

Energy Technology Data Exchange (ETDEWEB)

Agosteo, S. [Dipartimento di Ingegneria Nucleare, Politecnico di Milano, via Ponzio 34/3, 20133 Milan (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Milano, via Celoria 16, 20133 Milan (Italy); Birattari, C. [Istituto Nazionale di Fisica Nucleare, Sezione di Milano, via Celoria 16, 20133 Milan (Italy); Universita degli Studi di Milano, Dipartimento di Fisica, via Celoria 16, 20133 Milan (Italy); Dimovasili, E. [CERN, 1211 Geneva 23 (Switzerland); Foglio Para, A. [Dipartimento di Ingegneria Nucleare, Politecnico di Milano, via Ponzio 34/3, 20133 Milan (Italy); Silari, M. [CERN, 1211 Geneva 23 (Switzerland)]. E-mail: marco.silari@cern.ch; Ulrici, L. [CERN, 1211 Geneva 23 (Switzerland); Vincke, H. [CERN, 1211 Geneva 23 (Switzerland)

2005-02-01

The neutron emission from 50 mm thick copper, silver and lead targets bombarded by a mixed proton/pion beam with momentum of 40 GeV/c were measured at the CERN Super Proton Synchrotron. The neutron yield and spectral fluence per incident particle on target were measured with an extended range Bonner sphere spectrometer in the angular range 30-135 deg with respect to the beam direction. Monte Carlo simulations with the FLUKA code were performed to provide a priori information for the unfolding of the experimental data. The spectral fluences show two peaks, an isotropic evaporation component centred at 3 MeV and a high-energy peak sitting around 100-150 MeV. The experimental neutron yields are given in four energy bins: <100 keV, 0.1-20 MeV, 20-500 MeV and 0.5-2 GeV. The total yields show a systematic discrepancy of 30-50%, with a peak of 70% at the largest angles, with respect to the results of the Monte Carlo simulations, which it is believed to be mainly due to uncertainties in the beam normalization factor. Analytic expressions are given for the variation of the integral yield as a function of emission angle and of target mass number.

Neutron production from 40 GeV/c mixed proton/pion beam on copper, silver and lead targets in the angular range 30-135 deg

International Nuclear Information System (INIS)

Agosteo, S.; Birattari, C.; Dimovasili, E.; Foglio Para, A.; Silari, M.; Ulrici, L.; Vincke, H.

2005-01-01

The neutron emission from 50 mm thick copper, silver and lead targets bombarded by a mixed proton/pion beam with momentum of 40 GeV/c were measured at the CERN Super Proton Synchrotron. The neutron yield and spectral fluence per incident particle on target were measured with an extended range Bonner sphere spectrometer in the angular range 30-135 deg with respect to the beam direction. Monte Carlo simulations with the FLUKA code were performed to provide a priori information for the unfolding of the experimental data. The spectral fluences show two peaks, an isotropic evaporation component centred at 3 MeV and a high-energy peak sitting around 100-150 MeV. The experimental neutron yields are given in four energy bins: <100 keV, 0.1-20 MeV, 20-500 MeV and 0.5-2 GeV. The total yields show a systematic discrepancy of 30-50%, with a peak of 70% at the largest angles, with respect to the results of the Monte Carlo simulations, which it is believed to be mainly due to uncertainties in the beam normalization factor. Analytic expressions are given for the variation of the integral yield as a function of emission angle and of target mass number

Neutron production from 40 GeV/c mixed proton/pion beam on copper, silver and lead targets in the angular range 30-135°

Science.gov (United States)

Agosteo, S.; Birattari, C.; Dimovasili, E.; Foglio Para, A.; Silari, M.; Ulrici, L.; Vincke, H.

2005-02-01

The neutron emission from 50 mm thick copper, silver and lead targets bombarded by a mixed proton/pion beam with momentum of 40 GeV/c were measured at the CERN Super Proton Synchrotron. The neutron yield and spectral fluence per incident particle on target were measured with an extended range Bonner sphere spectrometer in the angular range 30-135° with respect to the beam direction. Monte Carlo simulations with the FLUKA code were performed to provide a priori information for the unfolding of the experimental data. The spectral fluences show two peaks, an isotropic evaporation component centred at 3 MeV and a high-energy peak sitting around 100-150 MeV. The experimental neutron yields are given in four energy bins: <100 keV, 0.1-20 MeV, 20-500 MeV and 0.5-2 GeV. The total yields show a systematic discrepancy of 30-50%, with a peak of 70% at the largest angles, with respect to the results of the Monte Carlo simulations, which it is believed to be mainly due to uncertainties in the beam normalization factor. Analytic expressions are given for the variation of the integral yield as a function of emission angle and of target mass number.

Energy loss and straggling of MeV ions through biological samples

International Nuclear Information System (INIS)

Ma Lei; Wang Yugang; Xue Jianming; Chen Qizhong; Zhang Weiming; Zhang Yanwen

2007-01-01

Energy loss and energy straggling of energetic ions through natural dehydrated biological samples were investigated using transmission technique. Biological samples (onion membrane, egg coat, and tomato coat) with different mass thickness were studied, together with Mylar for comparison. The energy loss and energy straggling of MeV H and He ions after penetrating the biological and Mylar samples were measured. The experimental results show that the average energy losses of MeV ions through the biological samples are consistent with SRIM predictions; however, large deviation in energy straggling is observed between the measured results and the SRIM predictions. Taking into account inhomogeneity in mass density and structure of the biological sample, an energy straggling formula is suggested, and the experimental energy straggling values are well predicted by the proposed formula

Negative pion-nucleus elastic scattering at 30 and 50 MeV

International Nuclear Information System (INIS)

Seth, K.K.; Barlow, D.; Iversen, S.; Kaletka, M.; Nann, H.; Smith, D.; Artuso, M.; Burleson, G.; Blanpied, G.; Daw, G.; Burger, W.J.; Redwine, R.P.; Saghai, B.; Anderson, R.

1990-01-01

Differential cross sections for the elastic scattering of 30 and 50 MeV π - by nuclei ranging from 12 C to 208 Pb have been measured using a range spectrometer. Comparison is made with the predictions of a recent optical-model calculation and the general nature of discrepancies is discussed

CMS event at 900 GeV - 5 May 2015

CERN Document Server

CMS, Collaboration

2015-01-01

This proton collision di-jet event was detected at the CMS detector. The red bars represent the energy deposited in the electromagnetic calorimeter and the blue represent the energy in the hadronic calorimeter. The total hadronic and electromagnetic energy is approximately 30 GeV in each jet. The back-to-back jet cones can be clearly seen emanating from the vertex.

Neutron energy spectrum from 120 GeV protons on a thick copper target

Energy Technology Data Exchange (ETDEWEB)

Shigyo, Nobuhiro; /Kyushu U.; Sanami, Toshiya; /KEK, Tsukuba; Kajimoto, Tsuyoshi; /Kyushu U.; Iwamoto, Yosuke; /JAEA, Ibaraki; Hagiwara, Masayuki; Saito, Kiwamu; /KEK, Tsukuba; Ishibashi, Kenji; /Kyushu U.; Nakashima, Hiroshi; Sakamoto, Yukio; /JAEA, Ibaraki; Lee, Hee-Seock; /Pohang Accelerator Lab.; Ramberg, Erik; /Fermilab

2010-08-01

Neutron energy spectrum from 120 GeV protons on a thick copper target was measured at the Meson Test Beam Facility (MTBF) at Fermi National Accelerator Laboratory. The data allows for evaluation of neutron production process implemented in theoretical simulation codes. It also helps exploring the reasons for some disagreement between calculation results and shielding benchmark data taken at high energy accelerator facilities, since it is evaluated separately from neutron transport. The experiment was carried out using a 120 GeV proton beam of 3E5 protons/spill. Since the spill duration was 4 seconds, protoninduced events were counted pulse by pulse. The intensity was maintained using diffusers and collimators installed in the beam line to MTBF. The protons hit a copper block target the size of which is 5cm x 5cm x 60 cm long. The neutrons produced in the target were measured using NE213 liquid scintillator detectors, placed about 5.5 m away from the target at 30{sup o} and 5 m 90{sup o} with respect to the proton beam axis. The neutron energy was determined by time-of-flight technique using timing difference between the NE213 and a plastic scintillator located just before the target. Neutron detection efficiency of NE213 was determined on basis of experimental data from the high energy neutron beam line at Los Alamos National Laboratory. The neutron spectrum was compared with the results of multiparticle transport codes to validate the implemented theoretical models. The apparatus would be applied to future measurements to obtain a systematic data set for secondary particle production on various target materials.

Evaluating the 239Pu Prompt Fission Neutron Spectrum Induced by Thermal to 30 MeV Neutrons

Directory of Open Access Journals (Sweden)

Neudecker D.

2016-01-01

Full Text Available We present a new evaluation of the 239Pu prompt fission neutron spectrum (PFNS induced by thermal to 30 MeV neutrons. Compared to the ENDF/B-VII.1 evaluation, this one includes recently published experimental data as well as an improved and extended model description to predict PFNS. For instance, the pre-equilibrium neutron emission component to the PFNS is considered and the incident energy dependence of model parameters is parametrized more realistically. Experimental and model parameter uncertainties and covariances are estimated in detail. Also, evaluated covariances are provided between all PFNS at different incident neutron energies. Selected evaluation results and first benchmark calculations using this evaluation are briefly discussed.

Feasibility of Colliding-beam fast-fission reactor via 238U80++238 U80+ --> 4 FF + 5n + 430 MeV beam with suppressed plutonium and direct conversion of fission fragment (FF) energy into electricity and/or Rocket propellant with high specific impulse

Science.gov (United States)

Maglich, Bogdan; Hester, Tim; Calsec Collaboration

2015-10-01

Uranium-uranium colliding beam experiment1, used fully ionized 238U92+ at energy 100GeV --> accelerated through 3 MV accelerator, will collide beam 240 MeV --> 4 FF + 5n + 430 MeV. Using a simple model1 fission σf ~ 100 b. Suppression of Pu by a factor of 106 will be achieved because NO thermal neutron fission can take place; only fast, 1-3 MeV, where σabs is negligible. Direct conversion of 95% of 430 MeV produced is carried by electrically charged FFs which are magnetically funneled for direct conversion of energy of FFs via electrostatic decelerators4,11. 90% of 930 MeV is electrically recoverable. Depending on the assumptions, we project electric _ power density production of 20 to 200 MWe m-3, equivalent to Thermal 1.3 - 13 GWthm-3. If one-half of unburned U is used for propulsion while rest powers system, heavy FF ion mass provides specific impulse Isp = 106 sec., 103 times higher than current rocket engines.

MEV Energy Electrostatic Accelerator Ion Beam Emittance Measurement

OpenAIRE

I.G. Ignat’ev; M.I. Zakharets; S.V. Kolinko; D.P. Shulha

2014-01-01

The testing equipment was designed, manufactured and tried out permitting measurements of total current, current profile and emittance of an ion beam extracted from the ion beam. MeV energy electrostatic accelerator ion H + beam emittance measurement results are presented.

Physics with a 15-30 GeV electron accelerator (ELFE)

International Nuclear Information System (INIS)

Frois, B.; Pire, B.

1993-01-01

Proposals for ELFE (Electron Laboratory For Europe), a 15-30 GeV high luminosity, continuous beam electron accelerator are discussed. These proposals form an extensive research program on exclusive reactions to probe the evolution of correlated quarks systems. Using the nucleus itself as a microscopic detector is one of the important ideas of this program. The same reaction is measured using nuclei of different sizes and thus the differences are observed in the evolution from quarks and gluons to hadrons in the nuclear medium. A brief overview of the physics with ELFE is presented. (R.P.) 1 tab

Determination of the LEP Beam Energy using Radiative Fermion-pair Events, 2004

CERN Document Server

Abbiendi, G; Åkesson, P F; Alexander, G; Allison, J; Amaral, P; Anagnostou, G; Anderson, K J; Asai, S; Axen, D A; Bailey, I; Barberio, E; Barillari, T; Barlow, R J; Batley, J Richard; Bechtle, P; Behnke, T; Bell, K W; Bell, P J; Bella, G; Bellerive, A; Benelli, G; Bethke, Siegfried; Biebel, O; Boeriu, O; Bock, P; Boutemeur, M; Braibant, S; Brown, R M; Burckhart, H J; Campana, S; Capiluppi, P; Carnegie, R K; Carter, A A; Carter, J R; Chang, C Y; Charlton, D G; Ciocca, C; Csilling, A; Cuffiani, M; Dado, S; de Roeck, A; De Wolf, E A; Desch, Klaus; Dienes, B; Donkers, M; Dubbert, J; Duchovni, E; Duckeck, G; Duerdoth, I P; Etzion, E; Fabbri, Franco Luigi; Ferrari, P; Fiedler, F; Fleck, I; Ford, M; Frey, A; Gagnon, P; Gary, J W; Geich-Gimbel, C; Giacomelli, G; Giacomelli, P; Giunta, M; Goldberg, J; Gross, E; Grunhaus, Jacob; Gruwé, M; Günther, P O; Sen-Gupta, A; Hajdu, C; Hamann, M; Hanson, G G; Harel, A; Hauschild, M; Hawkes, C M; Hawkings, R; Hemingway, R J; Herten, G; Heuer, R D; Hill, J C; Hoffman, K; Horváth, D; Igo-Kemenes, P; Ishii, K; Jeremie, H; Jovanovic, P; Junk, T R; Kanzaki, J; Karlen, Dean A; Kawagoe, K; Kawamoto, T; Keeler, R K; Kellogg, R G; Kennedy, B W; Kluth, S; Kobayashi, T; Kobel, M; Komamiya, S; Kramer, T; Krieger, P; Von Krogh, J; Kühl, T; Kupper, M; Lafferty, G D; Landsman, Hagar Yaël; Lanske, D; Lellouch, D; Letts, J; Levinson, L; Lillich, J; Lloyd, S L; Loebinger, F K; Lü, J; Ludwig, A; Ludwig, J; Mader, W; Marcellini, S; Martin, A J; Masetti, G; Mashimo, T; Mättig, P; McKenna, J A; McPherson, R A; Meijers, F; Menges, W; Merritt, F S; Mes, H; Meyer, N; Michelini, A; Mihara, S; Mikenberg, G; Miller, D J; Mohr, W; Mori, T; Mutter, A; Nagai, K; Nakamura, I; Nanjo, H; Neal, H A; Nisius, R; O'Neale, S W; Oh, A; Oreglia, M J; Orito, S; Pahl, C; Pásztor, G; Pater, J R; Pilcher, J E; Pinfold, J L; Plane, D E; Pooth, O; Przybycien, M B; Quadt, A; Rabbertz, K; Rembser, C; Renkel, P; Roney, J M; Rossi, A M; Rozen, Y; Runge, K; Sachs, K; Saeki, T; Sarkisyan-Grinbaum, E; Schaile, A D; Schaile, O; Scharff-Hansen, P; Schieck, J; Schörner-Sadenius, T; Schröder, M; Schumacher, M; Seuster, R; Shears, T G; Shen, B C; Sherwood, P; Skuja, A; Smith, A M; Sobie, R J; Söldner-Rembold, S; Spanó, F; Stahl, A; Strom, D; Ströhmer, R; Tarem, S; Tasevsky, M; Teuscher, R; Thomson, M A; Torrence, E; Toya, D; Tran, P; Trigger, I; Trócsányi, Z L; Tsur, E; Turner-Watson, M F; Ueda, I; Ujvári, B; Vollmer, C F; Vannerem, P; Vertesi, R; Verzocchi, M; Voss, H; Vossebeld, Joost Herman; Ward, C P; Ward, D R; Watkins, P M; Watson, A T; Watson, N K; Wells, P S; Wengler, T; Wermes, N; Wilson, G W; Wilson, J A; Wolf, G; Wyatt, T R; Yamashita, S; Zer-Zion, D; Zivkovic, L

2004-01-01

We present a determination of the LEP beam energy using "radiative return" fermion-pair events recorded at centre-of-mass energies from 183 GeV to 209 GeV. We find no evidence of a disagreement between the OPAL data and the LEP Energy Workings Group's standard calibration. Including the energy- averaged 11 MeV uncertainty in the standard determination, the beam energy we obtain from the OPAL data is higher than that obtained from the LEP calibration by 0+-34(stat.)+-27(syst.)MeV

(γ,n) reaction in nuclei of the 12<=A<=238 interval in the intermediate energy region (300 MeV-1000MeV)

International Nuclear Information System (INIS)

Martins, J.B.

1974-01-01

The absolute cross section of the 12 C(γ,n) 11 C, 19 F(γ,n) 18 F, 23 Na(γ,n) 22 Na, 31 P(γ,n) 30 P, 52 Cr(γ,n) 51 Cr, 55 Mn(γ,n) 54 Mn, 59 Co(γ,n) 58 Co, 75 As(γ,n) 74 As, 103 Rh(γn) 102 Rh, 127 I(γ,n) 126 I, 197 Au(γ,n) 196 Au and 238 U(γ,n) 237 U reactions were determined, experimentally, in the energy range from 300 MeV to 1000 MeV, using Bremsstrahlung photons. The measured cross sections were compared with results estimated by Monte Carlo Method applied to intranuclear cascades initiated by phothons. A functional dependence between the average value of (γ,n) absolute cross section and the mass number, were established. The (γ,n) absolute cross sections from simple relations, which transparencies of complexe nuclei for mesons and nucleons photo produced were also determined. (M.C.K.) [pt

First measurement of the polarisation asymmetry of a gamma-ray beam between 1.7 to 74 MeV with the HARPO TPC

Science.gov (United States)

Gros, P.; Amano, S.; Attié, D.; Bernard, D.; Bruel, P.; Calvet, D.; Colas, P.; Daté, S.; Delbart, A.; Frotin, M.; Geerebaert, Y.; Giebels, B.; Götz, D.; Hashimoto, S.; Horan, D.; Kotaka, T.; Louzir, Marc; Minamiyama, Y.; Miyamoto, S.; Ohkuma, H.; Poilleux, Patrick; Semeniouk, I.; Sizun, P.; Takemoto, A.; Yamaguchi, M.; Wang, S.

2016-07-01

Current γ-ray telescopes suffer from a gap in sensitivity in the energy range between 100 keV and 100 MeV, and no polarisation measurement has ever been done on cosmic sources above 1 MeV. Past and present e+e- pair telescopes are limited at lower energies by the multiple scattering of electrons in passive tungsten converter plates. This results in low angular resolution, and, consequently, a drop in sensitivity to point sources below 1 GeV. The polarisation information, which is carried by the azimuthal angle of the conversion plane, is lost for the same reasons. HARPO is an R&D program to characterise the operation of a gaseous detector (a Time Projection Chamber or TPC) as a high angular-resolution and sensitivity telescope and polarimeter for γ-rays from cosmic sources. It represents a first step towards a future space instrument in the MeV-GeV range. We built and characterised a 30cm cubic demonstrator [SPIE 91441M], and put it in a polarised γ-ray beam at the NewSUBARU accelerator in Japan. Data were taken at photon energies from 1.74MeV to 74MeV and with different polarisation configurations. We describe the experimental setup in beam. We then describe the software we developed to reconstruct the photon conversion events, with special focus on low energies. We also describe the thorough simulation of the detector used to compare results. Finally we will present the performance of the detector as extracted from this analysis and preliminary measurements of the polarisation asymmetry. This beam-test qualification of a gas TPC prototype in a γ-ray beam could open the way to high-performance -ray astronomy and polarimetry in the MeV-GeV energy range in the near future.

Upper limit on the inner radiation belt MeV electron intensity

Science.gov (United States)

Li, X; Selesnick, RS; Baker, DN; Jaynes, AN; Kanekal, SG; Schiller, Q; Blum, L; Fennell, J; Blake, JB

2015-01-01

No instruments in the inner radiation belt are immune from the unforgiving penetration of the highly energetic protons (tens of MeV to GeV). The inner belt proton flux level, however, is relatively stable; thus, for any given instrument, the proton contamination often leads to a certain background noise. Measurements from the Relativistic Electron and Proton Telescope integrated little experiment on board Colorado Student Space Weather Experiment CubeSat, in a low Earth orbit, clearly demonstrate that there exist sub-MeV electrons in the inner belt because their flux level is orders of magnitude higher than the background, while higher-energy electron (>1.6 MeV) measurements cannot be distinguished from the background. Detailed analysis of high-quality measurements from the Relativistic Electron and Proton Telescope on board Van Allen Probes, in a geo-transfer-like orbit, provides, for the first time, quantified upper limits on MeV electron fluxes in various energy ranges in the inner belt. These upper limits are rather different from flux levels in the AE8 and AE9 models, which were developed based on older data sources. For 1.7, 2.5, and 3.3 MeV electrons, the upper limits are about 1 order of magnitude lower than predicted model fluxes. The implication of this difference is profound in that unless there are extreme solar wind conditions, which have not happened yet since the launch of Van Allen Probes, significant enhancements of MeV electrons do not occur in the inner belt even though such enhancements are commonly seen in the outer belt. Key Points Quantified upper limit of MeV electrons in the inner belt Actual MeV electron intensity likely much lower than the upper limit More detailed understanding of relativistic electrons in the magnetosphere PMID:26167446

Phase shift analysis of ππ system at energies between 500 and 1370 MeV with Chew-Low extrapolation results from reactions π-p→pπ-π0 and π-p→nπ+π- at 3.92 GeV/c

International Nuclear Information System (INIS)

Mallet, Jacques.

1980-03-01

Experimental data (12 evts/μN→ππN reactions) were derived from the analysis of 450000 pictures obtained with the 2 meter hydrogen bubble chamber at CERN. The Chew-Low extrapolation method was used to obtain total and differential cross-sections of π +0 π - →π +0 π - reactions. Pseudo-peripherism hypothesis, in agreement with data at energy less 1 GeV, was modified to take into account the non-vanishing reactions amplitude at t=0, observed above 1 GeV. Several phase shift analyses were done, either with energy parametrisation of phase shifts, or at fixed energy. Main results concern the parameters of S* (Jsup(P)=0 + ) resonance which come out from a meromorphic parametrisation of the S 0 wave amplitude in the region of the KantiK channel threshold (987 MeV) and the dynamical wave structures in the f 0 (Jsup(P)=2 + ) resonance region. The agreement observed between these results and those of main previous experiments is a proof of the usefulness of the extrapolation method above 1 GeV [fr

Photon mass energy absorption coefficients from 0.4 MeV to 10 MeV for silicon, carbon, copper and sodium iodide

International Nuclear Information System (INIS)

Oz, H.; Gurler, O.; Gultekin, A.; Yalcin, S.; Gundogdu, O.

2006-01-01

The absorption coefficients have been widely used for problems and applications involving dose calculations. Direct measurements of the coefficients are difficult, and theoretical computations are usually employed. In this paper, analytical equations are presented for determining the mass energy absorption coefficients for gamma rays with an incident energy range between 0.4 MeV and 10 MeV in silicon, carbon, copper and sodium iodide. The mass energy absorption coefficients for gamma rays were calculated, and the results obtained were compared with the values reported in the literature.

Photon mass energy absorption coefficients from 0.4 MeV to 10 MeV for silicon, carbon, copper and sodium iodide

Energy Technology Data Exchange (ETDEWEB)

Oz, H.; Gurler, O.; Gultekin, A. [Uludag University, Bursa (Turkmenistan); Yalcin, S. [Kastamonu University, Kastamonu (Turkmenistan); Gundogdu, O. [University of Surrey, Guildford (United Kingdom)

2006-07-15

The absorption coefficients have been widely used for problems and applications involving dose calculations. Direct measurements of the coefficients are difficult, and theoretical computations are usually employed. In this paper, analytical equations are presented for determining the mass energy absorption coefficients for gamma rays with an incident energy range between 0.4 MeV and 10 MeV in silicon, carbon, copper and sodium iodide. The mass energy absorption coefficients for gamma rays were calculated, and the results obtained were compared with the values reported in the literature.

Neutron Energy Spectra from Neutron Induced Fission of 235U at 0.95 MeV and of 238U at 1.35 and 2.02 MeV

Energy Technology Data Exchange (ETDEWEB)

Almen, E; Holmqvist, B; Wiedling, T

1971-09-15

The shapes of fission neutron spectra are of interest for power reactor calculations. Recently it has been suggested that the neutron induced fission spectrum of 235U may be harder than was earlier assumed. For this reason measurements of the neutron spectra of some fissile isotopes are in progress at our laboratory. This report will present results from studies of the energy spectra of the neutrons emitted in the neutron induced fission of 235U and 238U. The measurements were performed at an incident neutron energy of 0.95 MeV for 235U and at energies of 1.35 and 2.02 MeV for 238U using time-of-flight techniques. The time-of-flight spectra were only analysed at energies higher than those of the incident neutrons and up to about 10 MeV. Corrections for neutron attenuation in the uranium samples were calculated using a Monte Carlo program. The corrected fission neutron spectra were fitted to Maxwellian temperature distributions. For 235U a temperature of 1.27 +- 0.01 MeV gives the best fit to the experimental data and for 238U the corresponding values are 1.29 +- 0.03 MeV at 1.35 MeV and 1.29 +- 0.02 MeV at 2.02 MeV

Neutron Elastic Scattering Cross Sections of Iron and Zinc in the Energy Region 2.5 to 8.1 MeV

International Nuclear Information System (INIS)

Holmqvist, B.; Johansson, S.G.; Lodin, G.; Wiedling, T.; Kiss, A.

1966-12-01

Angular distributions were measured for the elastic scattering of neutrons from iron at five energies between 3.0 and 8. 1 MeV and from zinc at eight energies between 2.5 and 8.1 MeV. Time-of-flight technique was used. Corrections for neutron flux attenuation, multiple elastic scattering, and the finite geometry of the source-sample detector system were made by using a Monte Carlo program. An optical model potential with Saxon-Woods form factors was used to fit theoretical angular distributions to the experimental ones. The parameter values giving the best fits to the experimental distributions were calculated by a computer

Neutron Elastic Scattering Cross Sections of Iron and Zinc in the Energy Region 2.5 to 8.1 MeV

Energy Technology Data Exchange (ETDEWEB)

Holmqvist, B; Johansson, S G; Lodin, G; Wiedling, T [AB Atomenergi, Nyko eping (Sweden); Kiss, A [Inst. for Experimental Physics, Univ. of Debrecen, De brecen (Hungary)

1966-12-15

Angular distributions were measured for the elastic scattering of neutrons from iron at five energies between 3.0 and 8. 1 MeV and from zinc at eight energies between 2.5 and 8.1 MeV. Time-of-flight technique was used. Corrections for neutron flux attenuation, multiple elastic scattering, and the finite geometry of the source-sample detector system were made by using a Monte Carlo program. An optical model potential with Saxon-Woods form factors was used to fit theoretical angular distributions to the experimental ones. The parameter values giving the best fits to the experimental distributions were calculated by a computer.

Neutron scattering from 208Pb at 30.4 and 40.0 MeV and isospin dependence of the nucleon optical potential

Science.gov (United States)

Devito, R. P.; Khoa, Dao T.; Austin, Sam M.; Berg, U. E. P.; Loc, Bui Minh

2012-02-01

Background: Analysis of data involving nuclei far from stability often requires the optical potential (OP) for neutron scattering. Because neutron data are seldom available, whereas proton scattering data are more abundant, it is useful to have estimates of the difference of the neutron and proton optical potentials. This information is contained in the isospin dependence of the nucleon OP. Here we attempt to provide it for the nucleon-208Pb system.Purpose: The goal of this paper is to obtain accurate n+208Pb scattering data and use it, together with existing p+208Pb and 208Pb(p,n)208BiIAS* data, to obtain an accurate estimate of the isospin dependence of the nucleon OP at energies in the 30-60-MeV range.Method: Cross sections for n+208Pb scattering were measured at 30.4 and 40.0 MeV, with a typical relative (normalization) accuracy of 2-4% (3%). An angular range of 15∘ to 130∘ was covered using the beam-swinger time-of-flight system at Michigan State University. These data were analyzed by a consistent optical-model study of the neutron data and of elastic p+208Pb scattering at 45 and 54 MeV. These results were combined with a coupled-channel analysis of the 208Pb(p,n) reaction at 45 MeV, exciting the 0+ isobaric analog state (IAS) in 208Bi.Results: The new data and analysis give an accurate estimate of the isospin impurity of the nucleon-208Pb OP at 30.4 MeV caused by the Coulomb correction to the proton OP. The corrections to the real proton OP given by the CH89 global systematics were found to be only a few percent, whereas for the imaginary potential it was greater than 20% at the nuclear surface. On the basis of the analysis of the measured elastic n+208Pb data at 40 MeV, a Coulomb correction of similar strength and shape was also predicted for the p+208Pb OP at energies around 54 MeV.Conclusions: Accurate neutron scattering data can be used in combination with proton scattering data and (p,n) charge exchange data leading to the IAS to obtain reliable

Analysis of the neutron energy spectra from the sup(208)Pb (p,n) sup(208)Bi reaction at Esub(p)=200 MeV

International Nuclear Information System (INIS)

Ershov, S.N.; Fayans, S.A.; Gareev, F.A.; Pyatov, N.I.

1986-01-01

Microscopic calculation of the small-angle neutron energy spectra from the 208 Pb (p, n) 208 Bi reaction at Esub(p)=200 MeV are presented. It is shown that the distorted-wave impulse approximation and the microscopic theory of finite Fermi systems can be employed for describing the low-energy excitation region 0 <= Q <= 30 MeV with small momentum transfers. A quantitative estimate is obtained for the local charge of quasiparticles esub(q)[σtau]=0.8 that characterizes the quenching of the integral strength of spin-flip low-energy transitions and the relevant effects are discussed

Experimental study of energy dependence of proton induced fission cross sections for heavy nuclei in the energy range 200-1000 MeV

Energy Technology Data Exchange (ETDEWEB)

Kotov, A.A.; Gavrikov, Yu.A.; Vaishnene, L.A.; Vovchenko, V.G.; Poliakov, V.V.; Fedorov, O.Ya.; Chestnov, Yu.A.; Shchetkovskiy, A.I [Petersburg Nuclear Physics Institute, Gatchina, Leningrad district, Orlova roscha 1, 188300 (Russian Federation); Fukahori, T. [Japan Atomic Energy Research Institute, Tokai-mura, Ibaraki 319-1195 (Japan)

2005-07-01

The results of the total fission cross sections measurements for {sup nat}Pb, {sup 209}Bi, {sup 232}Th, {sup 233}U, {sup 235}U, {sup 238}U, {sup 237}Np and {sup 239}Pu nuclei at the energy proton range 200-1000 MeV are presented. Experiments were carried out at 1 GeV synchrocyclotron of Petersburg Nuclear Physics Institute (Gatchina). The measurement method is based on the registration in coincidence of both complementary fission fragments by two gas parallel plate avalanche counters, located at a short distance and opposite sides of investigated target. The insensitivity of parallel plate avalanche counters to neutron and light charged particles allowed us to place the counters together with target immediately in the proton beam providing a large solid angle acceptance for fission fragment registration and reliable identification of fission events. The proton flux on the target to be studied was determined by direct counting of protons by scintillation telescope. The measured energy dependence of the total fission cross sections is presented. Obtained results are compared with other experimental data as well as with calculation in the frame of the cascade evaporation model. (authors)

Intranuclear cascade evaporation model predictions of double differential A(p,xn) neutron cross sections and comparison with experiments at 318 MeV and 800 MeV proton energy

International Nuclear Information System (INIS)

Cloth, P.; Dragovitsch, P.; Filges, D.; Reul, C.

1989-08-01

The intranuclear-cascade evaporation model as implemented in the high energy radiation transport code HETC, subsystem of HERMES is used in the calculation of double differential cross sections of proton induced neutron production. The investigations were done on target elements C, Al, Ta, Ni, W, Pb, and U at 318 MeV incident proton energy and on C, Al, Pb, and U at 800 MeV, respectively. The predictions of the INCE model were compared with experimental data for double differential cross sections taken at 7.5 and 30 degrees scattering angles at the Los Alamos WNR facility utilizing the Time of Flight technique at LANL. The calculations performed here are part of a experimental-theoretical program within the LANL-KFA collaboration concerning medium energy cross section measurements mainly neutrons and state of the art computer code validations of these measurements. In general, the model predictions reproduce the correct neutron production for evaporation neutrons and are also in good agreement with the experimental data at high neutron energies. In the energy range dominated by preequilibrium processes an underestimation of experimental yields has to be remarked. (orig.)

Measurements of spallation neutrons from a thick lead target bombarded with 0.5 and 1.5 GeV protons

Energy Technology Data Exchange (ETDEWEB)

Meigo, Shin-ichiro; Takada, Hiroshi; Chiba, Satoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment] [and others

1997-03-01

Double differential neutron spectra from a thick lead target bombarded with 0.5 and 1.5 GeV protons have been measured with the time-of-flight technique. In order to obtain the neutron spectra without the effect of the flight time fluctuation by neutron scattering in the target, an unfolding technique has also been employed in the low energy region below 3 MeV. The measured data have been compared with the calculated results of NMTC/JAERI-MCNP-4A code system. It has been found that the code system gives about 50 % lower neutron yield than the experimental ones in the energy region between 20 and 80 MeV for both incident energies. The disagreements, however, have been improved well by taking account of the inmedium nucleon-nucleon scattering cross sections in the NMTC/JAERI code. (author)

Photo-neutron yields from thin and thick targets irradiated by 2.0 GeV electrons

International Nuclear Information System (INIS)

Hee-Seock, Lee; Syuichi, Ban; Toshiya, Sanami; Kazutoshi, Takahashi; Tatsuhiko, Sato; Kazuo, Shin

2005-01-01

The photo-neutron yields from thin and thick targets irradiated by high energy electrons were studied. The photo-neutron spectra at 90 deg C relative to the incident 2.0 GeV electrons were measured by the pulsed beam time-of-flight technique using the Pilot-U plastic scintillator and the NE213 liquid scintillator with 2 inches in length and 2 inches in diameter. Targets, from low-Z element (carbon) to high-Z element (bismuth) and with thin (0.5 Xo) and thick (10 Xo) thickness, were used in this study. The differential photo-neutron yields between 2 MeV (mainly 8 MeV) and 400 MeV were obtained. The systematics was studied to make empirical yield terms for shielding application. Recently, the study of the angular distributed yields was conducted at two other observing angles, 48 deg C and 140 deg C. The photo-neutron yields between 8 MeV and 250 MeV were obtained for thick targets. The experimental data were compared with results calculated using the EGS4+PICA3 or the MCNPX 2.5d code. (authors)

The main ring polarimeter at KEK 12 GeV PS

International Nuclear Information System (INIS)

Sato, Hikaru; Hiramatsu, Shigenori; Toyama, Takeshi; Arakawa, Dai; Sakamoto, Hiroshi; Imai, Ken-ichi; Tamura, Norio.

1984-03-01

An internal polarimeter was constructed to detect the beam polarization from T sub(P) = 500 MeV to 12 GeV. The polarimeter was installed in the main ring of KEK proton synchrotron and successfully used for the measurement of the beam polarization at 500 MeV in order to study depolarizing resonances during acceleration in the booster synchrotron. We report the design and the performance of the polarimeter and the results of the first measurement. (author)

Searches for supersymmetry in the photon(s) plus missing energy channels at $\\sqrt{s}$ = 161 GeV and 172 GeV

CERN Document Server

Barate, R.; Decamp, D.; Ghez, Philippe; Goy, C.; Lees, J.P.; Lucotte, A.; Minard, M.N.; Nief, J.Y.; Pietrzyk, B.; Casado, M.P.; Chmeissani, M.; Comas, P.; Crespo, J.M.; Delfino, M.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, L.; Juste, A.; Martinez, M.; Merino, G.; Miquel, R.; Mir, L.M.; Padilla, C.; Park, I.C.; Pascual, A.; Perlas, J.A.; Riu, I.; Sanchez, F.; Colaleo, A.; Creanza, D.; de Palma, M.; Gelao, G.; Iaselli, G.; Maggi, G.; Maggi, M.; Marinelli, N.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Alemany, R.; Bazarko, A.O.; Becker, U.; Bright-Thomas, P.; Cattaneo, M.; Cerutti, F.; Dissertori, G.; Drevermann, H.; Forty, R.W.; Frank, M.; Hagelberg, R.; Hansen, J.B.; Harvey, John; Janot, P.; Jost, B.; Kneringer, E.; Lehraus, I.; Mato, P.; Minten, A.; Moneta, L.; Pacheco, A.; Pusztaszeri, J.F.; Ranjard, F.; Rizzo, G.; Rolandi, Gigi; Rousseau, D.; Schlatter, D.; Schmitt, M.; Schneider, O.; Tejessy, W.; Teubert, F.; Tomalin, I.R.; Wachsmuth, H.; Wagner, A.; Ajaltouni, Z.; Barres, A.; Boyer, C.; Falvard, A.; Ferdi, C.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Rosnet, P.; Rossignol, J.M.; Fearnley, T.; Hansen, J.D.; Hansen, J.R.; Hansen, P.H.; Nilsson, B.S.; Rensch, B.; Waananen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Vayaki, A.; Blondel, A.; Brient, J.C.; Machefert, F.; Rouge, A.; Rumpf, M.; Valassi, A.; Videau, H.; Boccali, T.; Focardi, E.; Parrini, G.; Zachariadou, K.; Cavanaugh, R.; Corden, M.; Georgiopoulos, C.; Huehn, T.; Jaffe, D.E.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Casper, D.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G.P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Dorris, S.J.; Halley, A.W.; Knowles, I.G.; Lynch, J.G.; O'Shea, V.; Raine, C.; Scarr, J.M.; Smith, K.; Teixeira-Dias, P.; Thompson, A.S.; Thomson, Evelyn J.; Thomson, F.; Turnbull, R.M.; Buchmuller, O.; Dhamotharan, S.; Geweniger, C.; Graefe, G.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E.E.; Putzer, A.; Sommer, J.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D.M.; Cameron, W.; Dornan, P.J.; Girone, M.; Goodsir, S.; Martin, E.B.; Morawitz, P.; Moutoussi, A.; Nash, J.; Sedgbeer, J.K.; Spagnolo, P.; Stacey, A.M.; Williams, M.D.; Ghete, V.M.; Girtler, P.; Kuhn, D.; Rudolph, G.; Betteridge, A.P.; Bowdery, C.K.; Buck, P.G.; Colrain, P.; Crawford, G.; Finch, A.J.; Foster, F.; Hughes, G.; Jones, R.W.L.; Sloan, T.; Whelan, E.P.; Williams, M.I.; Giehl, I.; Hoffmann, C.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.G.; van Gemmeren, P.; Zeitnitz, C.; Aubert, J.J.; Benchouk, C.; Bonissent, A.; Bujosa, G.; Carr, J.; Coyle, P.; Diaconu, C.; Ealet, A.; Fouchez, D.; Konstantinidis, N.; Leroy, O.; Motsch, F.; Payre, P.; Talby, M.; Sadouki, A.; Thulasidas, M.; Tilquin, A.; Trabelsi, K.; Aleppo, M.; Antonelli, M.; Ragusa, F.; Berlich, R.; Blum, W.; Buescher, Volker; Dietl, H.; Ganis, G.; Gotzhein, C.; Kroha, H.; Lutjens, G.; Lutz, G.; Manner, W.; Moser, H.G.; Richter, Robert, 1; Rosado-Schlosser, A.; Schael, S.; Settles, R.; Seywerd, H.; St. Denis, Richard Dante; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Boucrot, J.; Callot, O.; Chen, S.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.F.; Heusse, Ph.; Hocker, Andreas; Jacholkowska, A.; Jacquet, M.; Kim, D.W.; Le Diberder, F.; Lefrancois, J.; Lutz, A.M.; Nikolic, Irina; Schune, M.H.; Serin, L.; Simion, S.; Tournefier, E.; Veillet, J.J.; Videau, I.; Zerwas, D.; Azzurri, P.; Bagliesi, Giuseppe; Bettarini, S.; Bozzi, C.; Calderini, G.; Ciulli, V.; Dell'Orso, R.; Fantechi, R.; Ferrante, I.; Giassi, A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P.S.; Messineo, A.; Palla, F.; Sanguinetti, G.; Sciaba, A.; Sguazzoni, G.; Steinberger, J.; Tenchini, R.; Vannini, C.; Venturi, A.; Verdini, P.G.; Blair, G.A.; Bryant, L.M.; Chambers, J.T.; Gao, Y.; Green, M.G.; Medcalf, T.; Perrodo, P.; Strong, J.A.; von Wimmersperg-Toeller, J.H.; Botterill, D.R.; Clifft, R.W.; Edgecock, T.R.; Haywood, S.; Maley, P.; Norton, P.R.; Thompson, J.C.; Wright, A.E.; Bloch-Devaux, Brigitte; Colas, P.; Fabbro, B.; Kozanecki, W.; Lancon, E.; Lemaire, M.C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.F.; Rosowsky, A.; Roussarie, A.; Schuller, J.P.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S.N.; Dann, J.H.; Kim, H.Y.; Litke, A.M.; McNeil, M.A.; Taylor, G.; Booth, C.N.; Boswell, R.; Brew, C.A.J.; Cartwright, S.; Combley, F.; Kelly, M.S.; Lehto, M.; Newton, W.M.; Reeve, J.; Thompson, L.F.; Affholderbach, K.; Boehrer, Armin; Brandt, S.; Cowan, G.; Foss, J.; Grupen, C.; Lutters, G.; Saraiva, P.; Smolik, L.; Stephan, F.; Apollonio, M.; Bosisio, L.; Della Marina, R.; Giannini, G.; Gobbo, B.; Musolino, G.; Putz, J.; Rothberg, J.; Wasserbaech, S.; Williams, R.W.; Armstrong, S.R.; Charles, E.; Elmer, P.; Ferguson, D.P.S.; Gonzalez, S.; Greening, T.C.; Hayes, O.J.; Hu, H.; Jin, S.; McNamara, P.A., III; Nachtman, J.M.; Nielsen, J.; Orejudos, W.; Pan, Y.B.; Saadi, Y.; Scott, I.J.; Walsh, J.; Wu, Sau Lan; Wu, X.; Yamartino, J.M.; Zobernig, G.

1998-01-01

Searches for supersymmetric particles in channels with one or more photons and missing energy have been performed with data collected by the ALEPH detector at LEP. The data consist of 11.1 \\pb\\ at $\\sqrt{s} = 161 ~\\, \\rm GeV$, 1.1 \\pb\\ at 170 \\gev\\ and 9.5 \\pb\\ at 172 GeV. The \\eenunu\\ cross se ction is measured. The data are in good agreement with predictions based on the Standard Model, and are used to set upper limits on the cross sections for anomalous photon production. These limits are compared to two different SUSY models and used to set limits on the neutralino mass. A limit of 71 \\gevsq\\ at 95\\% C.L. is set on the mass of the lightest neutralin o ($\\tau_{\\chi_{1}^{0}} \\leq $ 3 ns) for the gauge-mediated supersymmetry breaking and LNZ models.

Space charge beam dynamics studies for a pulsed spallation source accelerator

Energy Technology Data Exchange (ETDEWEB)

Cho, Y.; Lessner, E.

1995-12-31

Feasibility studies for 2-GeV, 1-MW and 10-GeV, 5-MW rapid cycling synchrotrons (RCS) for spallation neutron sources have been completed. Both synchrotrons operate at a repetition rate of 30 Hz, and accelerate 1.04 {times} 10{sup 14} protons per pulse. The injection energy of the 2-GeV ring is 400 MeV, and the 10-GeV RCS accepts the beam from the 2-GeV machine. Work performed to-date includes calculation of the longitudinal space charge effects in the 400-MeV beam transfer line, and of both longitudinal and transverse space charge effects during the injection, capture and acceleration processes in the two rings. Results of space charge calculations in the rings led to proper choices of the working points and of rf voltage programs that prevents beam loss. Space charge effects in the 2-GeV synchrotron, in both transverse and longitudinal phase space, have major impact on the design due to the fact that the injection energy is 400 MeV. The design achieves the required performance while alleviating harmful effects due to space charge.

Experimental determination of the cross sections of the n-3He-system in the energy range of 1 to 40 MeV

International Nuclear Information System (INIS)

Haesner, B.

1982-08-01

Cross sections have been measured in the n+ 3 He-system over a broad energy range. The experiments were conducted using the pulsed white neutron beam at the Karlsruhe Neutron Time of Flight Facility. The total cross sections were measured from 1-40 MeV using the 190 m flight path with 1.5 ns time resolution. This represents a substantial improvement over previous measurements. Angular distributions (THETAsub(c.m.) = 33 0 -179 0 ) for the elastic n- 3 He scattering were measured simultaneously in the energy range from 5 to 30 MeV. A liquid 3 He scintillation detector was used as the scatterer. The statistical errors are less than 2% for most (> 90%) of the data. Through the use of the L 3 He detector absolute cross sections for the neutron induced reactions 3 He(n,p)T and 3 He(n,d)D could be measured from 1 to 30 MeV. These measurements are in good agreement with the results of the corresponding (p,n) and (d,n) reactions using detailed balance. (orig.) [de

Recent results from the Compton Observatory

Energy Technology Data Exchange (ETDEWEB)

Michelson, P.F.; Hansen, W.W. [Stanford Univ., CA (United States)

1994-12-01

The Compton Observatory is an orbiting astronomical observatory for gamma-ray astronomy that covers the energy range from about 30 keV to 30 GeV. The Energetic Gamma Ray Experiment Telescope (EGRET), one of four instruments on-board, is capable of detecting and imaging gamma radiation from cosmic sources in the energy range from approximately 20 MeV to 30 GeV. After about one month of tests and calibration following the April 1991 launch, a 15-month all sky survey was begun. This survey is now complete and the Compton Observatory is well into Phase II of its observing program which includes guest investigator observations. Among the highlights from the all-sky survey discussed in this presentation are the following: detection of five pulsars with emission above 100 MeV; detection of more than 24 active galaxies, the most distant at redshift greater than two; detection of many high latitude, unidentified gamma-ray sources, some showing significant time variability; detection of at least two high energy gamma-ray bursts, with emission in one case extending to at least 1 GeV. EGRET has also detected gamma-ray emission from solar flares up to energies of at least 2 GeV and has observed gamma-rays from the Large Magellanic Cloud.

A comparison of MCNP4C electron transport with ITS 3.0 and experiment at incident energies between 100 keV and 20 MeV: influence of voxel size, substeps and energy indexing algorithm

International Nuclear Information System (INIS)

Schaart, Dennis R.; Jansen, Jan Th.M.; Zoetelief, Johannes; Leege, Piet F.A. de

2002-01-01

The condensed-history electron transport algorithms in the Monte Carlo code MCNP4C are derived from ITS 3.0, which is a well-validated code for coupled electron-photon simulations. This, combined with its user-friendliness and versatility, makes MCNP4C a promising code for medical physics applications. Such applications, however, require a high degree of accuracy. In this work, MCNP4C electron depth-dose distributions in water are compared with published ITS 3.0 results. The influences of voxel size, substeps and choice of electron energy indexing algorithm are investigated at incident energies between 100 keV and 20 MeV. Furthermore, previously published dose measurements for seven beta emitters are simulated. Since MCNP4C does not allow tally segmentation with the *F8 energy deposition tally, even a homogeneous phantom must be subdivided in cells to calculate the distribution of dose. The repeated interruption of the electron tracks at the cell boundaries significantly affects the electron transport. An electron track length estimator of absorbed dose is described which allows tally segmentation. In combination with the ITS electron energy indexing algorithm, this estimator appears to reproduce ITS 3.0 and experimental results well. If, however, cell boundaries are used instead of segments, or if the MCNP indexing algorithm is applied, the agreement is considerably worse. (author)

Cross section ratio and angular distributions of the reaction p + d → 3He + η at 48.8 MeV and 59.8 MeV excess energy

International Nuclear Information System (INIS)

Adlarson, P.; Calen, H.; Fransson, K.; Gullstroem, C.O.; Heijkenskjoeld, L.; Hoeistad, B.; Johansson, T.; Marciniewski, P.; Redmer, C.F.; Wolke, M.; Zlomanczuk, J.; Augustyniak, W.; Marianski, B.; Morsch, H.P.; Trzcinski, A.; Zupranski, P.; Bardan, W.; Ciepal, I.; Czerwinski, E.; Hodana, M.; Jany, A.; Jany, B.R.; Jarczyk, L.; Kamys, B.; Kistryn, S.; Krzemien, W.; Magiera, A.; Moskal, P.; Ozerianska, I.; Podkopal, P.; Rudy, Z.; Skurzok, M.; Smyrski, J.; Wronska, A.; Zielinski, M.J.; Bashkanov, M.; Clement, H.; Doroshkevich, E.; Perez del Rio, E.; Pricking, A.; Skorodko, T.; Wagner, G.J.; Bergmann, F.S.; Demmich, K.; Goslawski, P.; Huesken, N.; Khoukaz, A.; Passfeld, A.; Taeschner, A.; Berlowski, M.; Stepaniak, J.; Bhatt, H.; Lalwani, K.; Varma, R.; Buescher, M.; Engels, R.; Goldenbaum, F.; Hejny, V.; Khan, F.A.; Lersch, D.; Lorentz, B.; Maier, R.; Ohm, H.; Prasuhn, D.; Schadmand, S.; Sefzick, T.; Stassen, R.; Sterzenbach, G.; Stockhorst, H.; Stroeher, H.; Wurm, P.; Zurek, M.; Coderre, D.; Ritman, J.; Erven, A.; Erven, W.; Kemmerling, G.; Kleines, H.; Wuestner, P.; Eyrich, W.; Hauenstein, F.; Krapp, M.; Zink, A.; Fedorets, P.; Foehl, K.; Goswami, A.; Grigoryev, K.; Kirillov, D.A.; Piskunov, N.M.; Klos, B.; Stephan, E.; Weglorz, W.; Kulessa, P.; Pysz, K.; Siudak, R.; Szczurek, A.; Kupsc, A.; Pszczel, D.; Mikirtychiants, M.; Pyszniak, A.; Roy, A.; Sawant, S.; Serdyuk, V.; Sopov, V.; Yamamoto, A.; Yurev, L.; Zabierowski, J.

2014-01-01

We present new data for angular distributions and on the cross section ratio of the p+d → 3 He + η reaction at excess energies of Q = 48.8 MeV and Q = 59.8 MeV. The data have been obtained at the WASA-at-COSY experiment (Forschungszentrum Juelich) using a proton beam and a deuterium pellet target. While the shape of obtained angular distributions show only a slow variation with the energy, the new results indicate a distinct and unexpected total cross section fluctuation between Q = 20 MeV and Q = 60 MeV, which might indicate the variation of the production mechanism within this energy interval. (orig.)

Missing mass spectra in pp inelastic scattering at total energies of 23 GeV and 31 GeV

CERN Document Server

Albrow, M G; Barber, D P; Bogaerts, A; Bosnjakovic, B; Brooks, J R; Clegg, A B; Erné, F C; Gee, C N P; Locke, D H; Loebinger, F K; Murphy, P G; Rudge, A; Sens, Johannes C; Van der Veen, F

1974-01-01

Results are reported of measurements of the momentum spectra of protons emitted at small angles in inelastic reactions at the CERN ISR. The data are for total energies s/sup 1///sub 2/ of 23 GeV and 31 GeV. The structure of the peak at low values of the missing mass M (of the system recoiling against the observed proton) is studied. The missing mass distributions have the form (M/sup 2/)-/sup B(t)/ where t is the four-momentum transfer squared. B(t) drops from 0.98+or-0.06 at t=-0.15 GeV/sup 2/ to 0.20+or-0.15 at t=-1.65 GeV/sup 2/. The results are compared with a simple triple-Regge formula. (12 refs).

Formation and de-excitation of hot nuclei in reactions induced by proton beams (475 MeV and 2 GeV) and {sup 3}He beam (2 GeV); Formation et desexcitation des noyaux chauds dans les reactions induites par des faisceaux de protons (475 MeV et 2 GeV) et d`{sup 3}He(2 GeV)

Energy Technology Data Exchange (ETDEWEB)

Ledoux, X.

1995-04-01

We are studying the formation and the de-excitation of hot nuclei created in reactions induced by light high energy projectiles. These reactions, described in a two step model: an intranuclear cascade followed by an evaporation phase, produce nuclei in which the collective modes (compression, rotation, deformation) are weakly excited. By measuring the neutron multiplicities, event by event with ORION, and the light charged particle energies and multiplicities one can evaluate the excitation energy distribution of the nuclei. At the same time, theoretical simulations are carried out using the intranuclear cascade code developed by J. Cugnon and the statistical de-excitation code GEMINI. The good agreement with experimental results indicate that 10% of the p-nucleus interactions lead to temperatures greater than 5 MeV. The observation of the fission of a nucleus with a temperature close to 5 MeV shows that the nucleus behaves as a set of bound nucleons and, that the temperature stability limit is not yet reached. The observed decline of fission probability at high excitation energies is most likely to be correlated to the appearance of an other de-excitation process (evaporation residues emission or multifragmentation) which could not be experimentally detected. Finally, in the last chapter, we briefly present the principle of transmutation for long-lived nuclear waste with a proton accelerator and underline the interest of the present work in such studies. (author). 54 refs., 80 figs., 13 tabs.

High energy proton simulation of 14-MeV neutron damage in Al2O3

International Nuclear Information System (INIS)

Muir, D.W.; Bunch, J.M.

1975-01-01

High-energy protons are a potentially useful tool for simulating the radiation damage produced by 14-MeV neutrons in CTR materials. A comparison is given of calculations and measurements of the relative damage effectiveness of these two types of radiation in single-crystal Al 2 O 3 . The experiments make use of the prominent absorption band at 206 nm as an index to lattice damage, on the assumption that peak absorption is proportional to the concentration of lattice vacancies. The induced absorption is measured for incident proton energies ranging from 5 to 15 MeV and for 14-MeV neutrons. Recoil-energy spectra are calculated for elastic and inelastic scattering using published angular distributions. Recoil-energy spectra also are calculated for the secondary alpha particles and 12 C nuclei produced by (p,p'α) reactions on 16 O. The recoil spectra are converted to damage-energy spectra and then integrated to yield the damage-energy cross section at each proton energy and for 14 MeV neutrons. A comparison of the calculations with experimental results suggests that damage energy, at least at high energies, is a reasonable criterion for estimating this type of radiation damage. (auth)

Impact of irradiations by protons with different energies on silicon sensors

International Nuclear Information System (INIS)

Neubueser, Coralie

2013-06-01

In the frame of the CMS tracker upgrade campaign the radiation damage of oxygenrich n-type silicon pad diodes induced by 23 MeV and 23 GeV protons was investigated. The diodes were manufactured by Hamamatsu Photonics. After irradiation with 1 MeV neutron equivalent fluences between 1 x 10 11 cm -2 and 1.5 x 10 15 cm -2 , the sensors were electrically characterized by means of capacitance-voltage (CV) and current-voltage (IV) measurements. Current pulses recorded by the Transient Current Technique (TCT) and Charge Collection Efficiency (CCE) measurements show a dependence of the bulk damage on the proton energy. At a fluence of Φ eq ∼3 x 10 14 cm -2 oxygen-rich n-type diodes demonstrate clear Space Charge Sign Inversion (SCSI) after 23 MeV proton irradiation. This effect does not appear after the irradiation with 23 GeV protons. Moreover, RD50 pad diodes were irradiated with 23 MeV protons, electrically characterized and compared to results obtained after 23 GeV irradiations. Our previous observation on the energy dependence of the radiation damage could be confirmed. In order to get a deeper understanding of the differences of the radiation induced defects, the Deep Level Transient Spectroscopy (DLTS) and Thermally Stimulated Current Technique (TSC) were utilized. Defects with impact on the space charge could be identified and characterized and it was possible to find some hints for the reason of the SCSI after 23 MeV proton irradiation. Moreover, a dependence on the oxygen concentration of the sensors could be observed.

Experimental study on the ionizing radiation field in absorbers irradiated by the 0.8 GeV and 1.2 GeV electrons

International Nuclear Information System (INIS)

Ambrosimov, V.K.; Kalmykov, N.N.; Kovalenko, G.D.

1987-01-01

The measurement results of spatial distribution of aluminium detector energy release and radioactivity in absorbers irradiated by 0.8 and 1.2 GeV electrons are given. Absorbers are made of aluminium, iron and lead, 30x30 cm size across the thickness is about 18 radiation length units. Thermoluminescence dosimeters LiF and radiochromium film dosimeters have been used to measure energy release. Induced activity of 18 F and 24 Na nuclides is determined in aluminium detectors. The experimental data are compared with the results of calculation carried out by the Monte-Carlo method

Calculation of the energy spectrum of atmospheric gamma-rays between 1 and 1000 MeV

International Nuclear Information System (INIS)

Martin, I.M.; Dutra, S.L.G.; Palmeira, R.A.R.

The energy spectrum of atmospheric gamma-rays at 4 g/cm 2 has been calculated for cut-off rigidities of 4.5, 10 and 16 GV. The considered processes for the production of these gamma-rays were the π 0 decay plus the bremsstrahlung from primary, secondary like splash and re-entrant albedo electrons. The calculations indicated that the spectrum could be fitted to a power law in energy, with the exponential index varying from 1.1 in the energy range 1 - 10 MeV, to 1.4 in the energy range 10 - 200 MeV and 1.8 in the energy range 200 - 1000 MeV. These results are discussed [pt

Measurement of Ay(θ) for n+208Pb from 6 to 10 MeV and the neutron-nucleus interaction over the energy range from bound states at -17 MeV up to scattering at 40 MeV

International Nuclear Information System (INIS)

Roberts, M.L.; Felsher, P.D.; Weisel, G.J.; Chen, Z.; Howell, C.R.; Tornow, W.; Walter, R.L.; Horen, D.J.

1991-01-01

High-accuracy measurements of A y (θ) data for elastic scattering and inelastic scattering to the first excited state for n+ 208 Pb have been performed at 6, 7, 8, 9, and 10 MeV. In addition, σ(θ) was measured at 8 MeV. These data provide an important subset for the growing database for the n+ 208 Pb system from bound-state energies to energies above 40 MeV, the limit of the range of interest here. This database has been interpreted via several approaches. First, a conventional Woods-Saxon spherical optical was used to obtain three potential representations for the energy range from 4 to 40 MeV: ''best fits'' at each energy, constant-geometry global fit with linear energy dependences for the potential strengths for the range 4.0--40 MeV, and an extension of the latter model to allow a linear energy dependence on the radii and diffuseness. A preference for a complex spin-orbit interaction was observed in all cases. Second, the dispersion relation was introduced into the spherical optical model to obtain a more ''realistic'' representation. In our approach, the strength and shape of the real potential was modified by calculating the dispersion-relation contributions that originate from the presence of the surface and volume imaginary terms. Two potentials were developed, one based only on the scattering data (from 4.0 to 40 MeV) and another based additionally on single-particle and single-hole information down to a binding energy of 17 MeV. In addition, the σ(θ) and A y (θ) measurements were compared to earlier conventional and dispersion-relation models. One of the latter of these included an l dependence in the absorptive surface term, and we applied this model in the 6- to 10-MeV region to describe all the σ(θ) and the new A y (θ)

Design of a 120 MeV $H^{-}$ Linac for CERN High-Intensity Applications

CERN Document Server

Gerigk, F

2002-01-01

The SPL (Superconducting Proton Linac) study at CERN foresees the construction of a 2.2 GeV linac as a high beam-power driver for applications such as a second-generation radioactive ion beam facility or a neutrino superbeam. At the same time such a high-performance injector would both modernize and improve the LHC injection chain. The 120 MeV normal-conducting section of the SPL could be used directly in a preliminary stage for H- charge-exchange injection into the PS Booster. This would increase the proton flux to the CERN experiments while also improving the quality and reliability of the beams for the LHC. The 120 MeV linac consists of a front-end, a conventional Drift Tube Linac (DTL) to 40 MeV and a Cell Coupled Drift Tube Linac (CCDTL) to the full energy. All the RF structures will operate at 352 MHz, using klystrons and RF equipment recovered from the LEP collider. This paper concentrates on the design of the 3 to 120 MeV section. It introduces the design criteria for high-stability beam optics and th...

Cross section ratio and angular distributions of the reaction p + d → {sup 3}He + η at 48.8 MeV and 59.8 MeV excess energy

Energy Technology Data Exchange (ETDEWEB)

Adlarson, P.; Calen, H.; Fransson, K.; Gullstroem, C.O.; Heijkenskjoeld, L.; Hoeistad, B.; Johansson, T.; Marciniewski, P.; Redmer, C.F.; Wolke, M.; Zlomanczuk, J. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (Sweden); Augustyniak, W.; Marianski, B.; Morsch, H.P.; Trzcinski, A.; Zupranski, P. [National Centre for Nuclear Research, Department of Nuclear Physics, Warsaw (Poland); Bardan, W.; Ciepal, I.; Czerwinski, E.; Hodana, M.; Jany, A.; Jany, B.R.; Jarczyk, L.; Kamys, B.; Kistryn, S.; Krzemien, W.; Magiera, A.; Moskal, P.; Ozerianska, I.; Podkopal, P.; Rudy, Z.; Skurzok, M.; Smyrski, J.; Wronska, A.; Zielinski, M.J. [Jagiellonian University, Institute of Physics, Krakow (Poland); Bashkanov, M.; Clement, H.; Doroshkevich, E.; Perez del Rio, E.; Pricking, A.; Skorodko, T.; Wagner, G.J. [Eberhard-Karls-Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Physikalisches Institut der Universitaet Tuebingen, Kepler Center fuer Astro- und Teilchenphysik, Tuebingen (Germany); Bergmann, F.S.; Demmich, K.; Goslawski, P.; Huesken, N.; Khoukaz, A.; Passfeld, A.; Taeschner, A. [Westfaelische Wilhelms-Universitaet Muenster, Institut fuer Kernphysik, Muenster (Germany); Berlowski, M.; Stepaniak, J. [National Centre for Nuclear Research, High Energy Physics Department, Warsaw (Poland); Bhatt, H.; Lalwani, K.; Varma, R. [Indian Institute of Technology Bombay, Department of Physics, Mumbai, Maharashtra (India); Buescher, M.; Engels, R.; Goldenbaum, F.; Hejny, V.; Khan, F.A.; Lersch, D.; Lorentz, B.; Maier, R.; Ohm, H.; Prasuhn, D.; Schadmand, S.; Sefzick, T.; Stassen, R.; Sterzenbach, G.; Stockhorst, H.; Stroeher, H.; Wurm, P.; Zurek, M. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); Coderre, D.; Ritman, J. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); Ruhr-Universitaet Bochum, Institut fuer Experimentalphysik I, Bochum (Germany); Erven, A.; Erven, W.; Kemmerling, G.; Kleines, H.; Wuestner, P. [Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); Forschungszentrum Juelich, Zentralinstitut fuer Engineering, Elektronik und Analytik, Juelich (Germany); Eyrich, W.; Hauenstein, F.; Krapp, M.; Zink, A. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erlangen (Germany); Fedorets, P. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); State Scientific Center of the Russian Federation, Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Foehl, K. [Justus-Liebig-Universitaet Giessen, II. Physikalisches Institut, Giessen (Germany); Goswami, A. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); Indian Institute of Technology Indore, Department of Physics, Indore, Madhya Pradesh (India); Grigoryev, K. [Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); RWTH Aachen, III. Physikalisches Institut B, Physikzentrum, Aachen (Germany); Petersburg Nuclear Physics Institute, High Energy Physics Division, Leningrad district (Russian Federation); Kirillov, D.A.; Piskunov, N.M. [Joint Institute for Nuclear Physics, Veksler and Baldin Laboratory of High Energiy Physics, Moscow region (Russian Federation); Klos, B.; Stephan, E.; Weglorz, W. [University of Silesia, August Chelkowski Institute of Physics, Katowice (Poland); Kulessa, P.; Pysz, K.; Siudak, R.; Szczurek, A. [Polish Academy of Sciences, The Henryk Niewodniczanski Institute of Nuclear Physics, Krakow (Poland); Kupsc, A.; Pszczel, D. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (Sweden); National Centre for Nuclear Research, High Energy Physics Department, Warsaw (Poland); Mikirtychiants, M. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (DE); Ruhr-Universitaet Bochum, Institut fuer Experimentalphysik I, Bochum (DE); Petersburg Nuclear Physics Institute, High Energy Physics Division, Leningrad district (RU); Pyszniak, A. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (SE); Jagiellonian University, Institute of Physics, Krakow (PL); Roy, A. [Indian Institute of Technology Indore, Department of Physics, Indore, Madhya Pradesh (IN); Sawant, S. [Indian Institute of Technology Bombay, Department of Physics, Mumbai, Maharashtra (IN); Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (DE); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (DE); Serdyuk, V. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (DE); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (DE); Joint Institute for Nuclear Physics, Dzhelepov Laboratory of Nuclear Problems, Moscow region (RU); Sopov, V. [State Scientific Center of the Russian Federation, Institute for Theoretical and Experimental Physics, Moscow (RU); Yamamoto, A. [High Energy Accelerator Research Organization KEK, Tsukuba, Ibaraki (JP); Yurev, L. [Joint Institute for Nuclear Physics, Dzhelepov Laboratory of Nuclear Problems, Moscow region (RU); Zabierowski, J. [National Centre for Nuclear Research, Department of Cosmic Ray Physics, Lodz (PL); Collaboration: WASA-at-COSY Collaboration

2014-06-15

We present new data for angular distributions and on the cross section ratio of the p+d → {sup 3}He + η reaction at excess energies of Q = 48.8 MeV and Q = 59.8 MeV. The data have been obtained at the WASA-at-COSY experiment (Forschungszentrum Juelich) using a proton beam and a deuterium pellet target. While the shape of obtained angular distributions show only a slow variation with the energy, the new results indicate a distinct and unexpected total cross section fluctuation between Q = 20 MeV and Q = 60 MeV, which might indicate the variation of the production mechanism within this energy interval. (orig.)

Attenuation of 10 MeV electron beam energy to achieve low doses does not affect Salmonella spp. inactivation kinetics

International Nuclear Information System (INIS)

Hieke, Anne-Sophie Charlotte; Pillai, Suresh D.

2015-01-01

The effect of attenuating the energy of a 10 MeV electron beam on Salmonella inactivation kinetics was investigated. No statistically significant differences were observed between the D 10 values of either Salmonella 4,[5],12:i:- or a Salmonella cocktail (S. 4,[5],12:i:-, Salmonella Heidelberg, Salmonella Newport, Salmonella Typhimurium, Salmonella) when irradiated with either a non-attenuated 10 MeV eBeam or an attenuated 10 MeV eBeam (~2.9±0.22 MeV). The results show that attenuating the energy of a 10 MeV eBeam to achieve low doses does not affect the inactivation kinetics of Salmonella spp. when compared to direct 10 MeV eBeam irradiation. - Highlights: • 10 MeV eBeam energy was attenuated to 2.9±0.22 MeV using HDPE sheets. • Attenuation of eBeam energy does not affect the inactivation kinetics of Salmonella. • Microbial inactivation is independent of eBeam energy in the range of 3–10 MeV

Neutron capture cross sections of rhodium, thulium, iridium, and gold between 0.5 and 3.0 MeV

International Nuclear Information System (INIS)

Joly, S.; Voignier, J.; Grenier, G.; Drake, D.M.; Nilsson, L.

1979-01-01

Measurements of the neutron capture cross sections of rhodium, thulium, gold, and iridium were carried out in the 0.5- to 3.0-MeV energy range. The cross sections are deduced from the capture gamma-ray spectra recorded by a NaI spectrometer consisting of central and annulus detectors. Time-of-flight techniques are used to improve the signal-to-background ratio. When comparison is possible, the present results are found to be in general agreement with the previous data. 5 figures, 3 tables

Proceedings of the 6. National Meeting on Intermediate Energy Physics

International Nuclear Information System (INIS)

1986-01-01

Several works on nuclear, hadron and quark physics are presented covering both aspects; theoretical and experimental, are presented. Emphasis is given in the intermediate energy region, several MeV centil few GeV. (L.C.) [pt

Ratios of charged antiparticles to particles near midrapidity in Au+Au collisions at (sNN)=200 GeV

Science.gov (United States)

Back, B. B.; Baker, M. D.; Barton, D. S.; Betts, R. R.; Ballintijn, M.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Decowski, M. P.; Garcia, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Michałowski, J.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steadman, S. G.; Steinberg, P.; Stephans, G. S.; Stodulski, M.; Sukhanov, A.; Tang, J.-L.; Teng, R.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Verdier, R.; Wadsworth, B.; Wolfs, F. L.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysłouch, B.

2003-02-01

The ratios of charged antiparticles to particles have been obtained for pions, kaons, and protons near midrapidity in central Au+Au collisions at (sNN)=200 GeV. Ratios of /=1.025±0.006(stat.)±0.018(syst.), /=0.95±0.03(stat.)±0.03(syst.), and / =0.73±0.02(stat.)±0.03(syst.) have been observed. The / and / ratios are consistent with a baryochemical potential μB of 27 MeV, roughly a factor of 2 smaller than in (sNN)=130 GeV collisions. The data are compared to results from lower energies and model calculations. Our accurate measurements of the particle ratios impose stringent constraints on current and future models dealing with baryon production and transport.

Search for supersymmetry in the photon(s) plus missing energy channels at sqrt(s)=161 GeV and 172 GeV

Science.gov (United States)

ALEPH Collaboration; Barate, R.; Buskulic, D.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Lucotte, A.; Minard, M.-N.; Nief, J.-Y.; Pietrzyk, B.; Casado, M. P.; Chmeissani, M.; Comas, P.; Crespo, J. M.; Delfino, M.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, Ll.; Juste, A.; Martinez, M.; Merino, G.; Miquel, R.; Mir, Ll. M.; Padilla, C.; Park, I. C.; Pascual, A.; Perlas, J. A.; Riu, I.; Sanchez, F.; Colaleo, A.; Creanza, D.; de Palma, M.; Gelao, G.; Iaselli, G.; Maggi, G.; Maggi, M.; Marinelli, N.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Alemany, R.; Bazarko, A. O.; Becker, U.; Bright-Thomas, P.; Cattaneo, M.; Cerutti, F.; Dissertori, G.; Drevermann, H.; Forty, R. W.; Frank, M.; Hagelberg, R.; Hansen, J. B.; Harvey, J.; Janot, P.; Jost, B.; Kneringer, E.; Lehraus, I.; Mato, P.; Minten, A.; Moneta, L.; Pacheco, A.; Pusztaszeri, J.-F.; Ranjard, F.; Rizzo, G.; Rolandi, L.; Rousseau, D.; Schlatter, D.; Schmitt, M.; Schneider, O.; Tejessy, W.; Teubert, F.; Tomalin, I. R.; Wachsmuth, H.; Wagner, A.; Ajaltouni, Z.; Barrès, A.; Boyer, C.; Falvard, A.; Ferdi, C.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Rosnet, P.; Rossignol, J.-M.; Fearnley, T.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Nilsson, B. S.; Rensch, B.; Wäänänen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Vayaki, A.; Blondel, A.; Brient, J. C.; Machefert, F.; Rougé, A.; Rumpf, M.; Valassi, A.; Videau, H.; Boccali, T.; Focardi, E.; Parrini, G.; Zachariadou, K.; Cavanaugh, R.; Corden, M.; Georgiopoulos, C.; Huehn, T.; Jaffe, D. E.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Casper, D.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Dorris, S. J.; Halley, A. W.; Knowles, I. G.; Lynch, J. G.; O'Shea, V.; Raine, C.; Scarr, J. M.; Smith, K.; Teixeira-Dias, P.; Thompson, A. S.; Thomson, E.; Thomson, F.; Turnbull, R. M.; Buchmüller, O.; Dhamotharan, S.; Geweniger, C.; Graefe, G.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E. E.; Putzer, A.; Sommer, J.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Dornan, P. J.; Girone, M.; Goodsir, S.; Martin, E. B.; Morawitz, P.; Moutoussi, A.; Nash, J.; Sedgbeer, J. K.; Spagnolo, P.; Stacey, A. M.; Williams, M. D.; Ghete, V. M.; Girtler, P.; Kuhn, D.; Rudolph, G.; Betteridge, A. P.; Bowdery, C. K.; Buck, P. G.; Colrain, P.; Crawford, G.; Finch, A. J.; Foster, F.; Hughes, G.; Jones, R. W. L.; Sloan, T.; Whelan, E. P.; Williams, M. I.; Giehl, I.; Hoffmann, C.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.-G.; van Gemmeren, P.; Zeitnitz, C.; Aubert, J. J.; Benchouk, C.; Bonissent, A.; Bujosa, G.; Carr, J.; Coyle, P.; Diaconu, C.; Ealet, A.; Fouchez, D.; Konstantinidis, N.; Leroy, O.; Motsch, F.; Payre, P.; Talby, M.; Sadouki, A.; Thulasidas, M.; Tilquin, A.; Trabelsi, K.; Aleppo, M.; Antonelli, M.; Ragusa, F.; Berlich, R.; Blum, W.; Büscher, V.; Dietl, H.; Ganis, G.; Gotzhein, C.; Kroha, H.; Lütjens, G.; Lutz, G.; Männer, W.; Moser, H.-G.; Richter, R.; Rosado-Schlosser, A.; Schael, S.; Settles, R.; Seywerd, H.; St. Denis, R.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Boucrot, J.; Callot, O.; Chen, S.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Höcker, A.; Jacholkowska, A.; Jacquet, M.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Nikolic, I.; Schune, M.-H.; Serin, L.; Simion, S.; Tournefier, E.; Veillet, J.-J.; Videau, I.; Zerwas, D.; Azzurri, P.; Bagliesi, G.; Bettarini, S.; Bozzi, C.; Calderini, G.; Ciulli, V.; dell'Orso, R.; Fantechi, R.; Ferrante, I.; Giassi, A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Sanguinetti, G.; Sciabà, A.; Sguazzoni, G.; Steinberger, J.; Tenchini, R.; Vannini, C.; Venturi, A.; Verdini, P. G.; Blair, G. A.; Bryant, L. M.; Chambers, J. T.; Gao, Y.; Green, M. G.; Medcalf, T.; Perrodo, P.; Strong, J. A.; von Wimmersperg-Toeller, J. H.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Haywood, S.; Maley, P.; Norton, P. R.; Thompson, J. C.; Wright, A. E.; Bloch-Devaux, B.; Colas, P.; Fabbro, B.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.-F.; Rosowsky, A.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S. N.; Dann, J. H.; Kim, H. Y.; Litke, A. M.; McNeil, M. A.; Taylor, G.; Booth, C. N.; Boswell, R.; Brew, C. A. J.; Cartwright, S.; Combley, F.; Kelly, M. S.; Lehto, M.; Newton, W. M.; Reeve, J.; Thompson, L. F.; Affholderbach, K.; Böhrer, A.; Brandt, S.; Cowan, G.; Foss, J.; Grupen, C.; Lutters, G.; Saraiva, P.; Smolik, L.; Stephan, F.; Apollonio, M.; Bosisio, L.; della Marina, R.; Giannini, G.; Gobbo, B.; Musolino, G.; Putz, J.; Rothberg, J.; Wasserbaech, S.; Williams, R. W.; Armstrong, S. R.; Charles, E.; Elmer, P.; Ferguson, D. P. S.; González, S.; Greening, T. C.; Hayes, O. J.; Hu, H.; Jin, S.; McNamara, P. A., III; Nachtman, J. M.; Nielsen, J.; Orejudos, W.; Pan, Y. B.; Saadi, Y.; Scott, I. J.; Walsh, J.; Wu, Sau Lan; Wu, X.; Yamartino, J. M.; Zobernig, G.

1998-02-01

Searches for supersymmetric particles in channels with one or more photons and missing energy have been performed with data collected by the ALEPH detector at LEP. The data consist of 11.1 pb-1 at sqrt(s)=161 GeV, 1.1 pb-1 at 170 GeV and 9.5 pb-1 at 172 GeV. The e+e--->νν¯γ(γ) cross section is measured. The data are in good agreement with predictions based on the Standard Model, and are used to set upper limits on the cross sections for anomalous photon production. These limits are compared to two different SUSY models and used to set limits on the neutralino mass. A limit of 71 GeV/c2 at 95% C.L. is set on the mass of the lightest neutralino (τχ10<= 3 ns) for the gauge-mediated supersymmetry breaking and LNZ models. © 1998

Neutron-photon multigroup cross sections for neutron energies up to 400 MeV: HILO86R

International Nuclear Information System (INIS)

Kotegawa, Hiroshi; Nakane, Yoshihiro; Hasegawa, Akira; Tanaka, Shun-ichi

1993-02-01

A macroscopic multigroup cross section library of 66 neutron and 22 photon groups for neutron energies up to 400 MeV: HILO86R is prepared for 10 typical shielding materials; water, concrete, iron, air, graphite, polyethylene, heavy concrete, lead, aluminum and soil. The library is a revision of the DLC-119/HILO86, in which only the cross sections below 19.6 MeV have been exchanged with a group cross section processed from the JENDL-3 microscopic cross section library. In the HILO86R library, self shielding factors are used to produce effective cross sections for neutrons less than 19.6 MeV considering rather coarse energy meshes. Energy spectra and dose attenuation in water, concrete and iron have been compared among the HILO, HILO86 and HILO86R libraries for different energy neutron sources. Significant discrepancy has been observed in the energy spectra less than a couple of MeV energy in iron among the libraries, resulting large difference in the dose attenuation. The difference was attributed to the effect of self-shielding factor, namely to the difference between infinite dilution and effective cross sections. Even for 400 MeV neutron source the influence of the self-shielding factor is significant, nevertheless only the cross sections below 19.6 MeV are exchanged. (author)

The 50 GeV program at SLAC

International Nuclear Information System (INIS)

Prescott, C.Y.

1994-03-01

SLAC has undertaken a modes programs to upgrade the beam energy for fixed target experiments to 50 GeV. This upgrade is possible due to the previous extensive development work on the linac accelerating gradient for the SLC, which has been operational for over five years. The SLC can deliver a beam of energy up to 60 GeV using a pulse compression technique in the rf system which trades pulse length for a higher pulse amplitude. This mode of operation has been reliable and routine for the SLC. However the beam line transport which takes electrons or positrons from the end of the linac to the target in End Station A has not been upgraded from the original design energy of 25 GeV. The 50 GeV upgrade for the fixed target experiments consists in modifying and increasing the number of beam line dipole magnets to reach 50 GeV, plus modernization of the beam line instrumentation and controls. The plans for spin structure experiments using electron beams at energies up to 50 GeV are described

A novel source of MeV positron bunches driven by energetic protons for PAS application

Energy Technology Data Exchange (ETDEWEB)

Tan, Zongquan, E-mail: tqq1123@mail.ustc.edu.cn [State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Xu, Wenzhen; Liu, Yanfen; Xiao, Ran; Kong, Wei [State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Ye, Bangjiao, E-mail: bjye@ustc.edu.cn [State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

2014-11-01

This paper proposes a novel methodology of MeV positrons generation for PAS application. Feasibility of this proposal analyzed by G4Beamline and Transport have shown reasonable success. Using 2 Hz, 1.6 GeV, 100 ns and 1.5 μC/bunch proton bunches for bombarding a graphite target, about 100 ns e{sup +} bunches are generated. Quasi-monochromatic positrons in the range of 1–10 MeV included in these bunches have a flux of >10{sup 7}/s, peak brightness of 10{sup 14}/s. A magnetic-confinement beamline is utilized to transport the positrons and a “Fast Beam Chopper” is unprecedentedly extended to chop those relativistic bunches. The positron beam can be finally characterized by the energy range of 1–10 MeV and bunch width from one hundred ps up to 1 ns. Such ultrashort bunches can be useful in tomography-type positron annihilation spectroscopy (PAS) as well as other applications.

A novel source of MeV positron bunches driven by energetic protons for PAS application

Science.gov (United States)

Tan, Zongquan; Xu, Wenzhen; Liu, Yanfen; Xiao, Ran; Kong, Wei; Ye, Bangjiao

2014-11-01

This paper proposes a novel methodology of MeV positrons generation for PAS application. Feasibility of this proposal analyzed by G4Beamline and Transport have shown reasonable success. Using 2 Hz, 1.6 GeV, 100 ns and 1.5 μC/bunch proton bunches for bombarding a graphite target, about 100 ns e+ bunches are generated. Quasi-monochromatic positrons in the range of 1-10 MeV included in these bunches have a flux of >107/s, peak brightness of 1014/s. A magnetic-confinement beamline is utilized to transport the positrons and a "Fast Beam Chopper" is unprecedentedly extended to chop those relativistic bunches. The positron beam can be finally characterized by the energy range of 1-10 MeV and bunch width from one hundred ps up to 1 ns. Such ultrashort bunches can be useful in tomography-type positron annihilation spectroscopy (PAS) as well as other applications.

A Complete Reporting of MCNP6 Validation Results for Electron Energy Deposition in Single-Layer Extended Media for Source Energies <= 1-MeV

Energy Technology Data Exchange (ETDEWEB)

Dixon, David A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hughes, Henry Grady [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-05-04

In this paper, we expand on previous validation work by Dixon and Hughes. That is, we present a more complete suite of validation results with respect to to the well-known Lockwood energy deposition experiment. Lockwood et al. measured energy deposition in materials including beryllium, carbon, aluminum, iron, copper, molybdenum, tantalum, and uranium, for both single- and multi-layer 1-D geometries. Source configurations included mono-energetic, mono-directional electron beams with energies of 0.05-MeV, 0.1-MeV, 0.3- MeV, 0.5-MeV, and 1-MeV, in both normal and off-normal angles of incidence. These experiments are particularly valuable for validating electron transport codes, because they are closely represented by simulating pencil beams incident on 1-D semi-infinite slabs with and without material interfaces. Herein, we include total energy deposition and energy deposition profiles for the single-layer experiments reported by Lockwood et al. (a more complete multi-layer validation will follow in another report).

Characterisation of a compton suppressed clover detector for high energy gamma rays (5 MeV ≤ E ≤ 11 MeV)

International Nuclear Information System (INIS)

Saha Sarkar, M.; Kshetri, Ritesh; Raut, Rajarshi; Mukherjee, A.; Goswami, A.; Ray, S.; Basu, P.; Majumder, H.; Bhattacharya, S.; Dasmahapatra, B.; Sinha, Mandira; Ray, Maitreyee

2004-01-01

The Clover detectors in their add back mode have been seen to be excellent tools for detecting high energy gamma rays (≥ 2 MeV). Recently studies were carried out on the characteristics of a Compton suppressed Clover germanium detector up to 5 MeV using a radioactive 66 Ga (T 1/2 =9.41 h) source for the first time

A Low-Energy Ring Lattice Design

International Nuclear Information System (INIS)

Cai, Yunhai

2002-01-01

The PEP-N project at SLAC [1] consists of a Very Low-Energy small electron Ring (VLER) that will collide with the low-energy 3.1 GeV positron beam (LER) of PEP-II, producing center-of-mass energies between the 1.1 GeV and the J/ψ. The beams will collide head-on and will be separated in the detector magnetic field which is part of the Interaction Region [2]. The IP β functions were chosen such as to optimize both luminosity and beam-beam tune shifts, while keeping the LER tune shifts small. This paper describes the lattice design of the VLER for the ''baseline'' at 500 MeV

Two body photodisintegration of the deuteron from 100 to 800 MeV

International Nuclear Information System (INIS)

Crawford, R.; Annand, J.R.M.; Anthony, I.; Altieri, S.; Pavia Univ.; Audit, G.; D'Hose, N.

1996-01-01

The total and the differential cross sections for the D(γ,p)n reaction have been measured over the photon energy range 100-800 MeV at the 855 MeV MAMI Microtron in Mainz. The data are presented in the form of thirty-five angular distributions at c.m. proton angles between 30 deg-160 deg in 10 deg intervals and at photon energies in steps of 20 MeV. Previous experimental work is reassessed in the light of the present results and the results compared with some recent theoretical calculations. (author)

Interactions of hadrons in nuclear emulsion in the energy range 60 GeV - 400 GeV

International Nuclear Information System (INIS)

Holynski, R.

1986-01-01

Interactions of pions and protons in the energy range 60 GeV in nuclear emulsion have been analysed. The fragmentation process of the struck nucleus as well as the multiple production of relativistic particles have been investigated as a function of the primary energy and the effective thickness of the target. It is shown that both, the fragmentation of the target nucleus and particle production, can be described by models in which the projectile (or its constituents) undergoes multiple collisions inside the target nucleus. In particular the particle production in the projectile fragmentation region in pion-nucleus interactions is well described by the additive quark model. 47 refs., 35 figs., 2 tabs. (author)

Effect of 3.0 MeV helium implantation on electrical characteristics of 4H-SiC BJTs

International Nuclear Information System (INIS)

Usman, Muhammad; Hallen, Anders; Ghandi, Reza; Domeij, Martin

2010-01-01

Degradation of 4H-SiC power bipolar junction transistors (BJTs) under the influence of a high-energy helium ion beam was studied. Epitaxially grown npn BJTs were implanted with 3.0 MeV helium in the fluence range of 10 10 -10 11 cm -2 . The devices were characterized by their current-voltage (I-V) behaviour before and after the implantation, and the results showed a clear degradation of the output characteristics of the devices. Annealing these implanted devices increased the interface traps between passivation oxide and the semiconductor, resulting in an increase of base current in the low-voltage operation range.

Energy dependence of the thermodynamical parameters in nucleus-nucleus collisions from 1A to 200A GeV

International Nuclear Information System (INIS)

Hong, Byung Sik

1999-01-01

The energy dependence of the thermodynamical parameters in nucleus-nucleus collisions are studied from 1A to 200A GeV in the framework of the statistical thermal model. The energy and entropy densities, as well as the pressure, of hot and dense hadronic matter are calculated by using the available input parameters of the model. No discontinuity or steep rise in the thermodynamical parameters has been found. The equation of state in terms of the speed of sound is investigated as a function of the energy density, and it increases monotonically up to 200A GeV. The estimated sonic velocities above 10A GeV are very close to that of an ideal ultrarelativistic hadron gas in the presence of resonances

Study of the high energy gamma-ray emission from the crab pulsar with the MAGIC telescope and Fermi-LAT

International Nuclear Information System (INIS)

Saito, Takayuki

2010-01-01

law with an exponential cut-off at a few GeV can well describe the energy spectrum of the Crab pulsar between 100 MeV and 30 GeV. This is consistent with the outer magnetosphere scenario and again, inconsistent with the inner magnetosphere scenario. The measurements of both experiments strongly disfavor the inner magnetosphere scenario. However, by combining the results of the two experiments, it turns out that even the standard outer magnetosphere scenario cannot explain the measurements. Various assumptions have been made to explain this discrepancy. By modifying the energy spectrum of the electrons which emit high energy gamma-rays via the curvature radiation, the combined measurements can be reproduced but further studies with higher statistics and a better energy resolution are needed to support this assumption. The energy-dependent pulse profile from 100 MeV to 100 GeV has also been studied in detail. Many interesting features have been found, among which the variabilities of both the pulse edges and the pulse peak phases are the most remarkable. More data would allow a more thorough investigation of the fine structure of the pulsar magnetosphere based on these features. Aiming for better observations of pulsars and other sources below 100 GeV, a new photosensor, HPD R9792U-40, has been investigated. Many beneficial properties, such as a very high photodetection efficiency, an extremely low ion-feedback probability and an excellent charge resolution have been found. (orig.)

Study of the high energy gamma-ray emission from the crab pulsar with the MAGIC telescope and Fermi-LAT

Energy Technology Data Exchange (ETDEWEB)

Saito, Takayuki

2010-12-06

law with an exponential cut-off at a few GeV can well describe the energy spectrum of the Crab pulsar between 100 MeV and 30 GeV. This is consistent with the outer magnetosphere scenario and again, inconsistent with the inner magnetosphere scenario. The measurements of both experiments strongly disfavor the inner magnetosphere scenario. However, by combining the results of the two experiments, it turns out that even the standard outer magnetosphere scenario cannot explain the measurements. Various assumptions have been made to explain this discrepancy. By modifying the energy spectrum of the electrons which emit high energy gamma-rays via the curvature radiation, the combined measurements can be reproduced but further studies with higher statistics and a better energy resolution are needed to support this assumption. The energy-dependent pulse profile from 100 MeV to 100 GeV has also been studied in detail. Many interesting features have been found, among which the variabilities of both the pulse edges and the pulse peak phases are the most remarkable. More data would allow a more thorough investigation of the fine structure of the pulsar magnetosphere based on these features. Aiming for better observations of pulsars and other sources below 100 GeV, a new photosensor, HPD R9792U-40, has been investigated. Many beneficial properties, such as a very high photodetection efficiency, an extremely low ion-feedback probability and an excellent charge resolution have been found. (orig.)

Photodisintegration cross section of the reaction (4)He(γ,p)(3)H between 22 and 30 MeV.

Science.gov (United States)

Raut, R; Tornow, W; Ahmed, M W; Crowell, A S; Kelley, J H; Rusev, G; Stave, S C; Tonchev, A P

2012-01-27

The two-body photodisintegration cross section of (4)He into a proton and triton was measured with monoenergetic photon beams in 0.5 MeV energy steps between 22 and 30 MeV. High-pressure (4)He-Xe gas scintillators of various (4)He/Xe ratios served as targets and detectors. Pure Xe gas scintillators were used for background studies. A NaI detector together with a plastic scintillator paddle was employed for determining the incident photon flux. Our comprehensive data set follows the trend of the theoretical calculations of the Trento group very well, although our data are consistently lower in magnitude by about 5%. However, they differ significantly from the majority of the previous data, especially from the recent data of Shima et al. The latter data had put into question the validity of theoretical approaches used to calculate core-collapse supernova explosions and big-bang nucleosynthesis abundances of certain light nuclei.

A Project Of The 2.5 Gev Booster-synchrotron In Binp

CERN Document Server

Barbashin, V M; Kremyanskaya, E V; Kvardakov, V A; Levichev, E B; Mishnev, S I; Skrinsky, A N; Smaluk, V V

2004-01-01

A project of the 2.5 GeV booster synchrotron to provide effective injection of electron and positron beams into VEPP-2000 and VEPP-4M storage rings, and for future facilities, is developing in BINP. The beams are injected to synchrotron at 510 MeV energy from a damping ring, which is the part of the new injection facility [1]. Small transverse size of the beam extracted from the damping ring allows us to design the synchrotron with rather small acceptance. Therefore, the aperture can be reduced essentially, which also decreases dimensions of the magnets and their power-consuming. In this report, the synchrotron parameters are presented, the basic systems are briefly described.

Impact of irradiations by protons with different energies on silicon sensors

Energy Technology Data Exchange (ETDEWEB)

Neubueser, Coralie

2013-06-15

In the frame of the CMS tracker upgrade campaign the radiation damage of oxygenrich n-type silicon pad diodes induced by 23 MeV and 23 GeV protons was investigated. The diodes were manufactured by Hamamatsu Photonics. After irradiation with 1 MeV neutron equivalent fluences between 1 x 10{sup 11} cm{sup -2} and 1.5 x 10{sup 15} cm{sup -2}, the sensors were electrically characterized by means of capacitance-voltage (CV) and current-voltage (IV) measurements. Current pulses recorded by the Transient Current Technique (TCT) and Charge Collection Efficiency (CCE) measurements show a dependence of the bulk damage on the proton energy. At a fluence of {Phi}{sub eq}{approx}3 x 10{sup 14} cm{sup -2} oxygen-rich n-type diodes demonstrate clear Space Charge Sign Inversion (SCSI) after 23 MeV proton irradiation. This effect does not appear after the irradiation with 23 GeV protons. Moreover, RD50 pad diodes were irradiated with 23 MeV protons, electrically characterized and compared to results obtained after 23 GeV irradiations. Our previous observation on the energy dependence of the radiation damage could be confirmed. In order to get a deeper understanding of the differences of the radiation induced defects, the Deep Level Transient Spectroscopy (DLTS) and Thermally Stimulated Current Technique (TSC) were utilized. Defects with impact on the space charge could be identified and characterized and it was possible to find some hints for the reason of the SCSI after 23 MeV proton irradiation. Moreover, a dependence on the oxygen concentration of the sensors could be observed.

The JHP 200-MeV proton linear accelerator

Energy Technology Data Exchange (ETDEWEB)

Kato, Takao [National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan)

1997-11-01

A 200-MeV proton linear accelerator for the Japanese Hadron Project (JHP) has been designed. It consists of a 3-MeV radio-frequency quadrupole linac (RFQ), a 50-MeV drift tube linac (DTL) and a 200-MeV separated-type drift tube linac (SDTL). A frequency of 324 MHz has been chosen for all of the rf structures. A peak current of 30 mA (H{sup -} ions) of 400 {mu}sec pulse duration will be accelerated at a repetition rate of 25 Hz. A future upgrade plan up to 400 MeV is also presented, in which annular-coupled structures (ACS) of 972 MHz are used in an energy range of above 150 or 200 MeV. One of the design features is its high performance for a beam-loss problem during acceleration. It can be achieved by separating the transition point in the transverse motion from that of the longitudinal motion. The transverse transition at a rather low-energy range decreases the effects of space-charge, while the longitudinal transition at a rather high-energy range decreases the effects of nonlinear problems related to acceleration in the ACS. Coupled envelope equations and equipartitioning theory are used for the focusing design. The adoption of the SDTL structure improves both the effective shunt impedance and difficulties in fabricating drift tubes with focusing magnets. An accurate beam-simulation code on a parallel supercomputer was used for confirming any beam-loss problem during acceleration. (author)

Measurements of energy behaviour of spin-dependent np—observables over 1.2-3.7 GeV energy region Dubna ``Delta-Sigma'' Experiment

Science.gov (United States)

Sharov, V. I.; Anischenko, N. G.; Antonenko, V. G.; Averichev, S. A.; Azhgirey, L. S.; Bartenev, V. D.; Bazhanov, N. A.; Belyaev, A. A.; Blinov, N. A.; Borisov, N. S.; Borzakov, S. B.; Borzunov, Yu. T.; Bushuev, Yu. P.; Chernenko, L. P.; Chernykh, E. V.; Chumakov, V. F.; Dolgh, S. A.; Fedorov, A. N.; Fimushkin, V. V.; Finger, M.; Finger, M.; Golovanov, L. B.; Gurevich, G. M.; Guriev, D. K.; Janata, A.; Kirillov, A. D.; Kolomiets, V. G.; Komogorov, E. V.; Kovalenko, A. D.; Kovalev, A. I.; Krasnov, V. A.; Krstonoshich, P.; Kuzmin, E. S.; Kuzmin, N. A.; Ladygin, V. P.; Lazarev, A. B.; Lehar, F.; de Lesquen, A.; Liburg, M. Yu.; Livanov, A. N.; Lukhanin, A. A.; Maniakov, P. K.; Matafonov, V. N.; Matyushevsky, E. A.; Moroz, V. D.; Morozov, A. A.; Neganov, A. B.; Nikolaevsky, G. P.; Nomofilov, A. A.; Panteleev, Tz.; Pillpenko, Yu. K.; Pisarev, I. L.; Plis, Yu. A.; Polunin, Yu. P.; Prokofiev, A. N.; Prytkov, V. Yu.; Rukoyatkin, P. A.; Schedrov, V. A.; Schevelev, O. N.; Shilov, S. N.; Shindin, R. A.; Slunecka, M.; Slunečková, V.; Starikov, A. Yu.; Stoletov, G. D.; Strunov, L. N.; Svetov, A. L.; Usov, Yu. A.; Vasiliev, T.; Volkov, V. I.; Vorobiev, E. I.; Yudin, I. P.; Zaitsev, I. V.; Zhdanov, A. A.; Zhmyrov, V. N.

2005-01-01

New accurate data on the neutron-proton spin-dependent total cross section difference Δ σ L( np) at the neutron beam kinetic energies 1.4, 1.7, 1.9 and 2.0 GeV are presented. A number of physical and methodical results on investigation of an elastic np→pn charge exchange process over a few GeV region are also presented. Measurements were carried out at the Synchrophasotron and Nuclotron of the Veksler and Baldin Laboratory of High Energies of the Joint Institute for Nuclear Research.

Characteristics of intermediate-energy nucleons emitted from 50 GeV

International Nuclear Information System (INIS)

Goyal, D.P.; Singh, S.; Arya, N.S.

1984-01-01

The multiplicity and angular distributions of intermediate-energy (grey) nucleons are studied from 50 GeV π - -nucleus data and compared with those available from π - -nucleus and p-nucleus interactions at other energies. The value of is found to be dependent both on the energy as well as on the projectile. The former variation is attributable to kinematics and the latter explainable on the basis of the additive quark model. The angular distribution of grey particles is found to be independent of energy, projectile and target, which supports the view that grey particles are chiefly due to knock-on recoiling protons. The various versions of the cascade model, however, are unable to explain any of the observed features of grey-particle distributions

Cross-sections for formation of {sup 89}Zr{sup m} through {sup 90}Zr(n,2n){sup 89}Zr{sup m} reaction over neutron energy range 13.73 MeV to 14.77 MeV

Energy Technology Data Exchange (ETDEWEB)

Attar, F.M.D. [Department of Physics, University of Pune, Pune-411007 (India); Mandal, R. [Department of Physics, University of Pune, Pune-411007 (India); Indian Institute of Technology, Kharagpur (India); Dhole, S.D. [Department of Physics, University of Pune, Pune-411007 (India); Saxena, A. [Nuclear Physics Division, BARC, Mumbai (India); Ashokkumar,; Ganesan, S. [Reactor Physics Design Division, BARC, Mumbai (India); Kailas, S. [Nuclear Physics Division, BARC, Mumbai (India); Bhoraskar, V.N. [Department of Physics, University of Pune, Pune-411007 (India)], E-mail: vnb@physics.unipune.ernet.in

2008-04-01

The cross-sections for formation of metastable state of {sup 89}Zr ({sup 89}Zr{sup m}, 0.588 MeV, 4.16 m) through {sup 90}Zr(n,2n){sup 89}Zr{sup m} reaction induced by 13.73 MeV to 14.77 MeV neutrons were measured for the first time and also theoretically estimated using Empire-II and Talys programs. At 13.73 MeV neutron energy, the {sup 89}Zr nuclei can be excited to metastable state, {sup 89}Zr{sup m}, when the first and the second emitted neutrons have energies lower than the most probable energy {approx}0.64 MeV. The probability of exciting {sup 89}Zr nuclei to energy levels higher than 0.588 MeV and therefore of populating the metastable state through decay process increases with increasing neutron energy. The measured cross-sections vary from 41{+-}3mb to 221{+-}15mb over neutron energies 13.73 MeV to 14.77 MeV, and are in agreement with the cross-sections estimated using Empire-II code. The formation of {sup 89}Zr{sup m} is favoured when the first and the second reaction neutrons are emitted with the most probable energies rather than lower energy, except for 13.73 MeV neutrons.

Two body photodisintegration of the deuteron from 100 to 800 MeV

Energy Technology Data Exchange (ETDEWEB)

Crawford, R.; Annand, J.R.M.; Anthony, I. [Glasgow Univ. (United Kingdom). Dept. of Physics and Astronomy; Ahrens, J.; Beck, R. [Mainz Univ. (Germany). Inst. fuer Kernphysik; Braghieri, A.; Pedroni, P. [Istituto Nazionale di Fisica Nucleare, Pavia (Italy); Altieri, S. [Istituto Nazionale di Fisica Nucleare, Pavia (Italy)]|[Pavia Univ. (Italy). Ist. di Fisica Nucleare; Audit, G.; D`Hose, N. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l`Instrumentation Associee] [and others

1996-01-01

The total and the differential cross sections for the D({gamma},p)n reaction have been measured over the photon energy range 100-800 MeV at the 855 MeV MAMI Microtron in Mainz. The data are presented in the form of thirty-five angular distributions at c.m. proton angles between 30 deg-160 deg in 10 deg intervals and at photon energies in steps of 20 MeV. Previous experimental work is reassessed in the light of the present results and the results compared with some recent theoretical calculations. (author). Submitted to Nuclear Physics, B (NL); 23 refs.

The (γ, p) reaction in 30Si, 68Zn and 130Te at intermediate energies

International Nuclear Information System (INIS)

Bulow, B.; Johnsson, B.; Nilsson, M.

1977-01-01

The yields of (γ, p) reactions on 30 Si, 68 Zn and 130 Te have been measured as a function of the bremsstrahlung end-point energy, Esub(γ, max), in the energy range 75-800 MeV, using the activation method. Cross sections have been deduced and are compared to results obtained using a semiempirical model. (Auth.)

The merging of the Intersecting Storage Rings for a 60 GeV collider with the 400 GeV proton synchrotron

International Nuclear Information System (INIS)

1978-01-01

Following the recommendation of the Workshop on Future ISR Physics, 1976, a study has been made of using the existing ISR (Intersecting Storage Rings) equipment at CERN to build a single 60 GeV storage ring (Merged ISR) for beam collision with the 400 GeV Super Proton Synchrotron (SPS). At a minimum cost of 103 MSF, a single-intersection physics facility with a 3.55 0 crossing angle, a luminosity of 1.2 10 30 cm -2 s -1 and a centre-of-mass energy of 255 GeV could be built. For a further 7 MSF, the luminosity could be easily raised to 3.8 10 30 cm -2 s -1 . Alternatively, the MISR can be built to give a single, zero-angle crossing with a luminosity of 1.1 10 32 cm -2 s -1 . The last solution is not recommended, however, as the free space around the intersection is extremely limited and the facility becomes very specialized in the type of physics experiments which could be performed. In all cases, the project could be completed in three years and two months with a 9 1/2-month shutdown for the SPS and 18 months between the closing down of the ISR and the start-up of MISR. (Auth.)

An Optical Model Study of Neutrons Elastically Scattered by Iron, Nickel, Cobalt, Copper, and Indium in the Energy Region 1.5 to 7.0 MeV

Energy Technology Data Exchange (ETDEWEB)

Holmqvist, B; Wiedling, T

1967-03-15

Angular distributions of elastically scattered neutrons have been measured for cobalt and copper at nine energies between 1.5 and 7.0 MeV, for natural iron at 4.6 MeV, for natural nickel and indium at four energies between 3.0 and 4.6 MeV, by using time-of-flight technique. The observed angular distributions were corrected for neutron flux attenuation, multiple elastic scattering, and the finite geometry of the source-sample-detector system by using a Monte Carlo program. Theoretical angular distributions have been fitted to the experimental angular distributions by using an optical model potential with Saxon-Woods form factors. A computer program was used to find parameter values of the potential giving the best fittings to the experimental angular distributions.

Fission-fragment angular distributions and total kinetic energies for 235U(n,f) from .18 to 8.83 MeV

International Nuclear Information System (INIS)

Meadows, J.W.; Budtz-Joergensen, C.

1982-01-01

A gridded ion chamber was used to measure the fission fragment angular distribution and total kinetic energy for the 235 U(n,f) reaction from 0.18 to 8.81 MeV neutron energy. The anisotropies are in generally good agreement with earlier measurements. The average total kinetic energy is approx. 0.2 MeV greater than the thermal value at neutron energies < 2 MeV and shows a sudden decrease of approx. 0.8 MeV between 4 and 5 MeV neutron energy, well below the (n, n'f) threshold. Possible causes of this decrease are a change in the mass distribution or decreased shell effects in the heavy fragment

Effect of 3.0 MeV helium implantation on electrical characteristics of 4H-SiC BJTs

Energy Technology Data Exchange (ETDEWEB)

Usman, Muhammad; Hallen, Anders; Ghandi, Reza; Domeij, Martin, E-mail: musman@kth.s [Microelectronics and Applied Physics, School of Communication and Information Technology, Royal Institute of Technology (KTH), Electrum 229, 16440 Kista (Sweden)

2010-11-01

Degradation of 4H-SiC power bipolar junction transistors (BJTs) under the influence of a high-energy helium ion beam was studied. Epitaxially grown npn BJTs were implanted with 3.0 MeV helium in the fluence range of 10{sup 10}-10{sup 11} cm{sup -2}. The devices were characterized by their current-voltage (I-V) behaviour before and after the implantation, and the results showed a clear degradation of the output characteristics of the devices. Annealing these implanted devices increased the interface traps between passivation oxide and the semiconductor, resulting in an increase of base current in the low-voltage operation range.

Time evolution of the spectral break in the high-energy extra component of GRB 090926A

Science.gov (United States)

Yassine, M.; Piron, F.; Mochkovitch, R.; Daigne, F.

2017-10-01

Aims: The prompt light curve of the long GRB 090926A reveals a short pulse 10 s after the beginning of the burst emission, which has been observed by the Fermi observatory from the keV to the GeV energy domain. During this bright spike, the high-energy emission from GRB 090926A underwent a sudden hardening above 10 MeV in the form of an additional power-law component exhibiting a spectral attenuation at a few hundreds of MeV. This high-energy break has been previously interpreted in terms of gamma-ray opacity to pair creation and has been used to estimate the bulk Lorentz factor of the outflow. In this article, we report on a new time-resolved analysis of the GRB 090926A broadband spectrum during its prompt phase and on its interpretation in the framework of prompt emission models. Methods: We characterized the emission from GRB 090926A at the highest energies with Pass 8 data from the Fermi Large Area Telescope (LAT), which offer a greater sensitivity than any data set used in previous studies of this burst, particularly in the 30-100 MeV energy band. Then, we combined the LAT data with the Fermi Gamma-ray Burst Monitor (GBM) in joint spectral fits to characterize the time evolution of the broadband spectrum from keV to GeV energies. We paid careful attention to the systematic effects that arise from the uncertainties on the LAT response. Finally, we performed a temporal analysis of the light curves and we computed the variability timescales from keV to GeV energies during and after the bright spike. Results: Our analysis confirms and better constrains the spectral break, which has been previously reported during the bright spike. Furthermore, it reveals that the spectral attenuation persists at later times with an increase of the break characteristic energy up to the GeV domain until the end of the prompt phase. We discuss these results in terms of keV-MeV synchroton radiation of electrons accelerated during the dissipation of the jet energy and inverse Compton

Effects of 3.1-MeV proton and 1-GeV Au-ion irradiation on the magnetic flux noise and critical current of YBa2Cu3O7-δ

International Nuclear Information System (INIS)

Shaw, T.J.; Clarke, J.; van Dover, R.B.; Schneemeyer, L.F.; White, A.E.

1996-01-01

We have used a dc superconducting quantum interference device to measure the spectral density of magnetic flux noise, S Φ (f), generated by vortex motion in crystals of YBa 2 Cu 3 O 7-δ (YBCO) both before and after irradiation with 3.1-MeV protons and 1-GeV Au ions. In addition, we have studied the effects of irradiation on the critical current J c of the same samples. Both types of irradiation reduced S Φ (f) at most temperatures and magnetic fields and increased J c at all temperatures and magnetic fields. By measuring S Φ (f) versus temperature, we extract the distribution of vortex pinning energies, D(U 0 ). Both crystals have peaks in D(U 0 ) near 0.1 eV and 0.2 eV before irradiation, and a much reduced peak near 0.1 eV after irradiation. The noise level after either kind of irradiation was substantially higher than in an unirradiated YBCO film. copyright 1996 The American Physical Society

Improvement of photoneutron spectrum measurement produced by bombardment of 2 GeV electrons above giant dipole resonance region

International Nuclear Information System (INIS)

Lee, H. S.; Park, J. S.; Choi, H. D.; Sato, Tatsuhiko; Shin, Kasuo; Ban, Syuichi

2000-01-01

Above the Giant Dipole Resonance (GDR) region, high energy photoneutron spectra produced by irradiation of 2.04 GeV electrons into Pb target were measured by Time-of-Flight (TOF) technique. The differential photoneutron yields were obtained at a fixed angle of 90 degrees to the electron beam direction. The TOF system consists of Pilot-U plastic scintillation detector, which has fast response time, and the high speed multiscaler or CAMAC TDC. In the improvement of experimental setup to extend the flight distance to 10.4 m lead to make the measurable energy to 500 MeV from 300 MeV. And using the TDC based electronics lead to use a veto counter. The results were compared with the calculated one by using EGS4 and Modified PICA95. The characteristics of this TOF system was introduced in this paper and the results for several measuring conditions, which are flight distance, TOF electronics, and type of neutron detector, were discussed to improve the accuracy of this measurement

A common origin of all the species of high energy cosmic rays?

CERN Document Server

Dar, Arnon; Antoniou, Nikos; Dar, Arnon; Antoniou, Nikos

2000-01-01

The cosmic ray nuclei with energy above a few GeV, the cosmic ray electrons of energy above a few MeV and the diffuse gamma-ray background above a few MeV, could all predominantly originate from our galaxy {\\it and its halo}. The mechanism accelerating hadrons and electrons is the same, the electron spectrum is modulated by inverse Compton scattering on the microwave background radiation, and the $\\gamma$-rays are the resulting recoiling photons. The spectra calculated on this basis agree with observations.

Measurement of small angle antiproton-proton elastic scattering at √s =546 and 1800 GeV

International Nuclear Information System (INIS)

Abe, F.; Albrow, M.; Amidei, D.; Anway-Wiese, C.; Apollinari, G.; Atac, M.; Auchincloss, P.; Azzi, P.; Bacchetta, N.; Baden, A.R.; Badgett, W.; Bailey, M.W.; Bamberger, A.; de Barbaro, P.; Barbaro-Galtieri, A.; Barnes, V.E.; Barnett, B.A.; Bauer, G.; Baumann, T.; Bedeschi, F.; Behrends, S.; Belforte, S.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Benlloch, J.; Bensinger, J.; Beretvas, A.; Berge, J.P.; Bertolucci, S.; Biery, K.; Bhadra, S.; Binkley, M.; Bisello, D.; Blair, R.; Blocker, C.; Bodek, A.; Bolognesi, V.; Booth, A.W.; Boswell, C.; Brandenburg, G.; Brown, D.; Buckley-Geer, E.; Budd, H.S.; Busetto, G.; Byon-Wagner, A.; Byrum, K.L.; Campagnari, C.; Campbell, M.; Caner, A.; Carey, R.; Carithers, W.; Carlsmith, D.; Carroll, J.T.; Cashmore, R.; Castro, A.; Cen, Y.; Cervelli, F.; Chadwick, K.; Chapman, J.; Chapin, T.J.; Chiarelli, G.; Chinowsky, W.; Cihangir, S.; Clark, A.G.; Cobal, M.; Connor, D.; Contreras, M.; Cooper, J.; Cordelli, M.; Crane, D.; Cunningham, J.D.; Day, C.; DeJongh, F.; Dell'Agnello, S.; Dell'Orso, M.; Demortier, L.; Denby, B.; Derwent, P.F.; Devlin, T.; Dickson, M.; Drucker, R.B.; Dunn, A.; Einsweiler, K.; Elias, J.E.; Ely, R.; Eno, S.; Errede, S.; Etchegoyen, A.; Farhat, B.; Frautschi, M.; Feldman, G.J.; Flaugher, B.; Foster, G.W.; Franklin, M.; Freeman, J.; Fuess, T.; Fukui, Y.; Garfinkel, A.F.; Gauthier, A.; Geer, S.; Gerdes, D.W.; Giannetti, P.; Giokaris, N.; Giromini, P.; Gladney, L.; Gold, M.; Gonzalez, J.; Goulianos, K.; Grassmann, H.; Grieco, G.M.; Grindley, R.; Grosso-Pilcher, C.; Haber, C.; Hahn, S.R.; Handler, R.; Hara, K.; Harral, B.; Harris, R.M.; Hauger, S.A.; Hauser, J.; Hawk, C.; Hessing, T.; Hollebeek, R.; Holloway, L.; Hoelscher, A.; Hong, S.; Houk, G.; Hu, P.; Hubbard, B.; Huffman, B.T.; Hughes, R.; Hurst, P.; Huth, J.; Hylen, J.; Incagli, M.; Ino, T.; Iso, H.; Jessop, C.P.; Johnson, R.P.; Joshi, U.; Kadel, R.W.; Kamon, T.; Kanda, S.; Kardelis, D.A.; Karliner, I.; Kearns, E.; Keeble, L.; Kephart, R.; Kesten, P.

1994-01-01

Antiproton-proton elastic scattering was measured at c.m.s. energies √s =546 and 1800 GeV in the range of four-momentum transfer squared 0.025 2 . The data are well described by the exponential form e bt with a slope b=15.28±0.58 (16.98±0.25) GeV -2 at √s =546 (1800) GeV. The elastic scattering cross sections are, respectively, σ el =12.87±0.30 and 19.70±0.85 mb

Sustained >100 MeV Gamma-Ray Emission: A Monitor for >300 MeV SEP Protons at the Sun

Science.gov (United States)

Share, G. H.; Murphy, R. J.

2017-12-01

Solar γ radiation is the product of proton and ion interactions in the solar atmosphere. The spectrum and temporal characteristics of the emission provides fundamental information on the ions at the Sun. Until the launch of the Fermi satellite, with its Large Area Telescope (LAT) sensitive to radiation above 100 MeV, most of the γ-ray observations were made in the nuclear energy range with radiation arising from interaction of one to tens of MeV ions produced in solar flares. Since 2008 the LAT has detected 30 high-energy γ-ray events with temporal and spectral characteristics that are distinct from the associated solar flare. We call this radiation Sustained Gamma-Ray Emission (SGRE) and briefly summarize its characteristics reported in a recent paper. The γ-ray spectra are consistent with pion decay radiation produced by protons above 300 MeV. The onset of the radiation most often occurs after the impulsive flare and the emission can last several hours. We find that the number of protons responsible for the SGRE is typically more than 10 times the number of flare-accelerated protons. These characteristics require that there be an additional source of energy to accelerate the protons to hundreds of MeV to produce the SGRE. As 28 of the 30 SGRE events are accompanied by fast CMEs, it is likely that these protons are accelerated by the same shock that produces gradual SEPs. We find that the number of protons >500 MeV in the accompanying SEPs is typically about 50-100 times the number of protons that return to the Sun to produce the SGRE. There also appear to be correlations between the numbers of SEP and SGRE protons and durations of >100 MeV SEP proton and SGRE events. We find that for all SGRE events where there were flare observations, the accompanying impulsive X-radiation reached energies >100 keV. In a limited study of 18 solar events with CME speeds >800 km/s we also find that the median SEP proton flux is 25 times higher when flare hard X-rays exceed 100

Development of polystyrene calorimeter for application at electron energies down to 1.5 MeV

DEFF Research Database (Denmark)

Miller, A.; Kovacs, A.; Kuntz, F.

2002-01-01

Polystyrene (PS) calorimeters developed at Riso National Laboratory for use below 4 MeV have been modified due to irradiation technology requirements concerning both design principles and dimensions. The temperature-time relationship after irradiation was measured, and two ways of dose measurement...... the average and the surface dose and to prove the applicability of the new low energy calorimeter for calibration purposes at 1.5 and 2 MeV electron energy. Alanine dosimeters of 2 mm thickness were used to calibrate the calorimeters and their use for nominal dose measurements was demonstrated in a series...... of intercomparisons. The use as routine dosimeters at electron accelerators operating in the energy range of 1.5-4 MeV was also demonstrated. (C) 2002 Elsevier Science Ltd. All rights reserved....

An energy dependent partial wave analysis of π+ p→ K+ σ+ between threshold and 2.35 GeV

International Nuclear Information System (INIS)

Candlin, D.J.; Lowe, D.C.; Peach, K.J.

1983-11-01

An energy dependent partial wave analysis of the reaction π + p → K + Σ + has been carried out between threshold and 2.35 GeV centre of mass energy using recently published, high statistical precision data. A single solution giving a satisfactory fit to the data has been found. In the region below 2 GeV the resonant features of the solution are compared with the QCD based model of Koniuk and Isgur. Above 2 GeV the states listed in the Particle Data group tables with two or more stars are observed but none of the dubious one star states is confirmed Significant SU(3) breaking is observed in some amplitudes. (author)

Propagation of GeV neutrinos through Earth

Science.gov (United States)

Olivas, Yaithd Daniel; Sahu, Sarira

2018-06-01

We have studied the Earth matter effect on the oscillation of upward going GeV neutrinos by taking into account the three active neutrino flavors. For neutrino energy in the range 3 to 12 GeV we observed three distinct resonant peaks for the oscillation process νe ↔νμ,τ in three distinct densities. However, according to the most realistic density profile of the Earth, the second peak at neutrino energy 6.18 GeV corresponding to the density 6.6 g/cm3 does not exist. So the resonance at this energy can not be of MSW-type. For the calculation of observed flux of these GeV neutrinos on Earth, we considered two different flux ratios at the source, the standard scenario with the flux ratio 1 : 2 : 0 and the muon damped scenario with 0 : 1 : 0. It is observed that at the detector while the standard scenario gives the observed flux ratio 1 : 1 : 1, the muon damped scenario has a different ratio. For muon damped case with Eν 20 GeV, we get the average Φνe ∼ 0 and Φνμ ≃Φντ ≃ 0.45. The upcoming PINGU will be able to shed more light on the nature of the resonance in these GeV neutrinos and hopefully will also be able to discriminate among different processes of neutrino production at the source in GeV energy range.

GXRD study of 100 MeV Fe9+ ion irradiated indium phosphide

International Nuclear Information System (INIS)

Dubey, R.L.; Dubey, S.K.; Kachhap, N.K.; Kanjilal, D.

2014-01-01

Swift heavy ions with MeV to GeV kinetic energy offer unique possibilities of modifying material properties. Each projectile passing through the target material causes loss of its energy by ion-electrons and ion-atoms interaction with the target material. The consequence of formal one is to change in surface properties and latter to produces damage deep in the target material near the projected range of projectile. In the present work, indium phosphide samples were irradiated at 100 MeV 56 Fe 9+ ions with different fluences varying from 1x10 12 to 1x10 14 ions cm -2 using the 15UD Pelletron facilities at Inter University Accelerator Centre (IUAC), New Delhi. Grazing angle X-ray diffraction technique was used to investigate the structural properties of irradiated indium phosphide at different depths. The GXRD spectra of non-irradiated and irradiated samples were recorded at different grazing angle i.e 1°, 2°, 3°, 4° and 5° to get the structural information over the projected range. The detailed result will be presented and discussed in the conference. (author)

HIGH-ENERGY EMISSION OF GRB 130427A: EVIDENCE FOR INVERSE COMPTON RADIATION

International Nuclear Information System (INIS)

Fan, Yi-Zhong; Zhang, Fu-Wen; He, Hao-Ning; Zhou, Bei; Yang, Rui-Zhi; Jin, Zhi-Ping; Wei, Da-Ming; Tam, P. H. T.; Liang, Yun-Feng

2013-01-01

A nearby superluminous burst GRB 130427A was simultaneously detected by six γ-ray space telescopes (Swift, the Fermi GLAST Burst Monitor (GBM)/Large Area Telescope, Konus-Wind, SPI-ACS/INTEGRAL, AGILE, and RHESSI) and by three RAPTOR full-sky persistent monitors. The isotropic γ-ray energy release is ∼10 54 erg, rendering it the most powerful explosion among gamma-ray bursts (GRBs) with a redshift z ≤ 0.5. The emission above 100 MeV lasted about one day, and four photons are at energies greater than 40 GeV. We show that the count rate of 100 MeV-100 GeV emission may be mainly accounted for by the forward shock synchrotron radiation and the inverse Compton radiation likely dominates at GeV-TeV energies. In particular, an inverse Compton radiation origin is favored for the ∼(95.3, 47.3, 41.4, 38.5, 32) GeV photons arriving at t ∼ (243, 256.3, 610.6, 3409.8, 34366.2) s after the trigger of Fermi-GBM. Interestingly, the external inverse Compton scattering of the prompt emission (the second episode, i.e., t ∼ 120-260 s) by the forward-shock-accelerated electrons is expected to produce a few γ-rays at energies above 10 GeV, while five were detected in the same time interval. A possible unified model for the prompt soft γ-ray, optical, and GeV emission of GRB 130427A, GRB 080319B, and GRB 090902B is outlined. Implications of the null detection of >1 TeV neutrinos from GRB 130427A by IceCube are discussed

Transverse energy production in 208Pb+Pb collisions at 158 GeV per nucleon

International Nuclear Information System (INIS)

Alber, T.; Appelshaeuser, H.; Baechler, J.; Bartke, J.; Bialkowska, H.; Bieser, F.; Bloomer, M.A.; Blyth, C.O.; Bock, R.; Bormann, C.; Brady, F.P.; Brockmann, R.; Buncic, P.; Caines, H.L.; Cebra, D.; Chan, P.; Cooper, G.E.; Cramer, J.G.; Cramer, P.B.; Csato, P.; Derado, I.; Dunn, J.; Eckardt, V.; Eckhardt, F.; Euler, S.; Ferguson, M.I.; Fischer, H.G.; Fodor, Z.; Foka, P.; Freund, P.; Fuchs, M.; Gal, J.; Gazdzicki, M.; Gladysz, E.; Grebieszkow, J.; Guenther, J.; Harris, J.W.; Heck, W.; Hegyi, S.; Hill, L.A.; Huang, I.; Howe, M.A.; Igo, G.; Irmscher, D.; Jacobs, P.; Jones, P.G.; Kadija, K.; Kecskemeti, J.; Kowalski, M.; Kuehmichel, A.; Lasiuk, B.; Margetis, S.; Mitchell, J.W.; Mock, A.; Nelson, J.M.; Odyniec, G.; Palinkas, J.; Palla, G.; Panagiotou, A.D.; Petridis, A.; Piper, A.; Poskanzer, A.M.; Prindle, D.J.; Puehlhofer, F.; Rauch, W.; Renfordt, R.; Retyk, W.; Ritter, H.G.; Roehrich, D.; Rudolph, H.; Runge, K.; Sandoval, A.; Sann, H.; Schaefer, E.; Schmitz, N.; Schoenfelder, S.; Seyboth, P.; Seyerlein, J.; Sikler, F.; Skrzypczak, E.; Stock, R.; Stroebele, H.; Szentpetery, I.; Sziklai, J.; Toy, M.; Trainor, T.A.; Trentalange, S.; Vassiliou, M.; Vesztergombi, G.; Vranic, D.; Wenig, S.; Whitten, C.; Wienold, T.; Wood, L.; Zimanyi, J.; Zhu, X.; Zybert, R.

1995-01-01

Measurements of the forward and the transverse energy in 158 GeV per nucleon 208 Pb+Pb collisions are presented. A total transverse energy of about 1 TeV is created in central collisions. An energy density of about 3GeV/fm 3 is estimated for near head-on collisions. Only statistical fluctuations are seen in the ratio of electromagnetic to hadronic transverse energy. copyright 1995 The American Physical Society

Saturne II: A 3 GeV proton synchrotron for nuclear physics

Energy Technology Data Exchange (ETDEWEB)

Faure, J; Penicaud, J P [Centre detude nucleaire de Saclay, Gif sur Yvette (France)

1978-07-01

A 3 GeV proton Synchrotron is now under completion at the Saclay Nuclear Research Center in France. This machine replaces the former Saturne Synchrotron built in 1958. The lattice type of the new machine is a strong focusing one, and the structure of the magnetic ring is made up to 16 bending magnets and 24 quadrupolar lenses. Due to the small injection energy (20 MeV), it has been necessary to design large aperture magnets. The two accelerating R.F. cavities need a wide range of tuning by ferrites from 0.86 to 8.3 MHz with a peak voltage 18 kV. The performances of the new machine are better adapted to the needs of Nuclear Physics. The main features of the extracted protons beam are an intensity of 2.10{sup 12} protons per second at a variable energy from 0.5 to 3 GeV, an energy spread of a few 10{sup -4} and a small emittance (horizontal {approx_equal} 6 {pi} mm.mrd, vertical 25 {pi} mm.mrad). Heavy ions up to N{sup 7+} and polarized particles (H{sup +} and D{sup +}) will be accelerated too, around 10{sup 9} per pulse on the target. On the experimental areas nine lines are fully equipped and four spectrometers will be set up. The first accelerated beam is expected in October 1978, and the physics experiments should start at the end of this year. (author)

Saturne II: a 3 GeV proton synchrotron for nuclear physics

International Nuclear Information System (INIS)

Faure, J.; Penicaud, J.P.

1978-01-01

A 3 GeV proton Synchrotron is now under completion at the Saclay Nuclear Research Center in France. This machine replaces the former Saturne Synchrotron built in 1958. The lattice type of the new machine is a strong focusing one, and the structure of the magnetic ring is made up of 16 bending magnets and 24 quadrupolar lenses. Due to the small injection energy (20 MeV), it has been necessary to design large aperture magnets. The two accelerating R.F. cavities need a wide range of tuning by ferrites from 0,86 to 8,3 MHz with a peak voltage of 18 kV. The performances of the new machine are better adaptated to the needs of Nuclear Physics. The main features of the extracted protons beam are an intensity of 2.10 12 protons per second at a variable energy from 0,5 to 3 GeV, an energy spread of a few 10 -4 and a small emittance (horizontal approximately 6 π mm.mrd, vertical 25 π mm.mrd). Heavy ions up to N 7+ and polarized particles (H + and D + ) will be accelerated too, around 10 9 per pulse on the target. On the experimental areas nine lines are fully equipped and four spectrometers will be set up. The first accelerated beam is expected in October 1978, and the physics experiments should start at the end of this year

Photoresponse of {sup 94}Mo at energies up to 8.6 MeV

Energy Technology Data Exchange (ETDEWEB)

Romig, Christopher; Fritzsche, M.; Lindenberg, K.; Pietralla, N.; Savran, D.; Sonnabend, K. [Institut fuer Kernphysik, Technische Universitaet, Darmstadt (Germany); Rusev, G.; Tonchev, A.P.; Tornow, W.; Weller, H.R. [Triangle Universities Nuclear Laboratory, Duke University, Durham, NC (United States); Zilges, A. [Institut fuer Kernphysik, Universitaet Koeln (Germany)

2009-07-01

The isotope {sup 94}Mo was investigated in nuclear resonance fluorescence experiments at the High Intensity Photon Setup (HIPS) at the S-DALINAC in Darmstadt using bremsstrahlung photons with energies of 7.65 and 8.6 MeV, respectively, and at the High Intensity {gamma}-ray Source (HI{gamma}S) at Duke University using photons from Laser Compton backscattering. Thereby over 60 excitations were found which could be assigned to {sup 94}Mo due to the highly enriched sample. In the energy region between 5.4 and 8 MeV many transitions could be classified as dipole transitions and cross sections, angular momentum quantum numbers, half-lifes and transition strengths were determined. At HI{gamma}S the parity quantum numbers of 40 excitations between 5.5 and 7.0 MeV could be determined. The methods and results are presented.

Performance of the 2 MeV microwave gun for the SSRL 150 MeV linac

International Nuclear Information System (INIS)

Borland, M.; Weaver, J.N.; Wiedemann, H.; Miller, R.H.; Tanabe, E.

1990-09-01

As described in a previous article, the preinjector linac for SSRL's 3 GeV synchrotron is fed by a 2 MeV, 1.5 A, low-emittance microwave gun, consisting of a thermionic cathode mounted in the first cell of a 1-1/2-cell S-band cavity. In this article, we report on the successful operation of the low-emittance gun, the longitudinally-bunching alpha-magnet, and the three-microbunch FET-pulsed beam-chopper. Simulations predict a normalized rms emittance at the gun exit of less than 10 π·m e c·μm; chromatic effects in transport optics increase this to approximately 30 π·m e c·μm. The gun was specifically designed to have a longitudinal phase-space suited to magnetic compression, as a result of which we predict that peak currents in excess of 300 A in a 1 ps bunch are feasible with the existing alpha-magnet. Results of simulations and experiments will be presented and compared. 13 refs., 9 figs

Calibration in photon radiation fields with energies above 3 MeV

International Nuclear Information System (INIS)

Bueermann, L.

1997-01-01

For determination of the response of dosemeters and dose ratemeters for photon energies above 3 MeV, the PTB uses reference radiation fields generated via the nuclear reactions 12 (p, p' γ) 12 C (4.4 MeV) and 19 F(p,αγ) 16 O (6-7 MeV). As a maximum, kerma rates of 1 mGy/h released in air can be achieved at 1 m distance from the target. The air kerma in the reference fields is determined with two different methods, i.e. by spectrometry using a Ge detector, and by ionometry using a graphite cavity ionisation chamber. The total uncertainty of the value determined for the air kerma (collision radiation) in the reference fields is 50% at a confidence level of 68.3%. (orig./CB) [de

Characterisation of a Compton suppressed Clover detector for high energy gamma rays (=<11MeV)

International Nuclear Information System (INIS)

Saha Sarkar, M.; Kshetri, Ritesh; Raut, Rajarshi; Mukherjee, A.; Sinha, Mandira; Ray, Maitreyi; Goswami, A.; Roy, Subinit; Basu, P.; Majumder, H.; Bhattacharya, S.; Dasmahapatra, B.

2006-01-01

Gamma ray spectra of two (p,γ) resonances have been utilised for the characterisation of the Clover detector at energies beyond 5MeV. Apart from the efficiency and the resolution of the detector, the shapes of the full energy peaks as well as the nature of the escape peaks which are also very crucial at higher energies have been analysed with special attention. Proper gain matching in software have checked deterioration in the energy resolution and distortion in the peak shape due to addback. The addback factors show sharp increasing trend even at energies around 11MeV

Characterisation of a Compton suppressed Clover detector for high energy gamma rays (=<11MeV)

Energy Technology Data Exchange (ETDEWEB)

Saha Sarkar, M. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India)]. E-mail: maitrayee.sahasarkar@saha.ac.in; Kshetri, Ritesh [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Raut, Rajarshi [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Mukherjee, A. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Sinha, Mandira [Gurudas College, Narkeldanga, Kolkata-700054 (India); Ray, Maitreyi [Behala College, Parnashree, Kolkata-700060 (India); Goswami, A. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Roy, Subinit [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Basu, P. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Majumder, H. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Bhattacharya, S. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Dasmahapatra, B. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India)

2006-01-01

Gamma ray spectra of two (p,{gamma}) resonances have been utilised for the characterisation of the Clover detector at energies beyond 5MeV. Apart from the efficiency and the resolution of the detector, the shapes of the full energy peaks as well as the nature of the escape peaks which are also very crucial at higher energies have been analysed with special attention. Proper gain matching in software have checked deterioration in the energy resolution and distortion in the peak shape due to addback. The addback factors show sharp increasing trend even at energies around 11MeV.

The spectrum of protons produced in pp collisions at 31 GeV total energy

CERN Document Server

Albrow, M G; Barber, D P; Bogaerts, A; Bosnjakovic, B; Brooks, J R; Clegg, A B; Erné, F C; Gee, C N P; Locke, D H; Loebinger, F K; Murphy, P G; Rudge, A; Sens, Johannes C; Van der Veen, F

1973-01-01

Data are reported on the distributions in longitudinal and transverse momentum of protons produced in the range 0.5GeV c.m. energy at the CERN ISR. The invariant inelastic cross section shows a peak at high longitudinal momenta. The shape of this peak suggests substantial production of states with masses up to at least 7 GeV. (4 refs).

High energy resolution characteristics on 14MeV neutron spectrometer for fusion experimental reactor

Energy Technology Data Exchange (ETDEWEB)

Iguchi, Tetsuo [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab.; Takada, Eiji; Nakazawa, Masaharu

1996-10-01

A 14MeV neutron spectrometer suitable for an ITER-like fusion experimental reactor is now under development on the basis of a recoil proton counter telescope principle in oblique scattering geometry. To verify its high energy resolution characteristics, preliminary experiments are made for a prototypical detector system. The comparison results show reasonably good agreement and demonstrate the possibility of energy resolution of 2.5% in full width at half maximum for 14MeV neutron spectrometry. (author)

Measurement of cross sections for the scattering of neutrons in the energy range from 2 MeV to 4 MeV with the 15N(p,n) reaction as neutron source

International Nuclear Information System (INIS)

Poenitz, Erik

2010-01-01

In future nuclear facilities, the materials lead and bismuth can play a more important role than in today's nuclear reactors. Reliable cross section data are required for the design of those facilities. In particular the neutron transport in the lead spallation target of an Accelerator-Driven Subcritical Reactor strongly depends on the inelastic neutron scattering cross sections in the energy region from 0.5 MeV to 6 MeV. In the recent 20 years, elastic and inelastic neutron scattering cross sections were measured with high precision for a variety of elements at the PTB time-of-flight spectrometer. The D(d,n) reaction was primarily used for the production of neutrons. Because of the Q value of the reaction and the available deuteron energies, neutrons in the energy range from 6 MeV to 16 MeV can be produced. For the cross section measurement at lower energies, however, another neutron producing reaction is required. The 15 N(p,n) 15 O reaction was chosen, as it allows the production of monoenergetic neutrons with up to 5.7MeV energy. In this work, the 15 N(p,n) reaction was studied with focus on the suitability as a source for monoenergetic neutrons in scattering experiments. This includes the measurement of differential cross sections for the neutron producing reaction and the choice of optimum target conditions. Differential elastic and inelastic neutron scattering cross sections were measured for lead at four energies in the region from 2 MeV to 4 MeV incident neutron energy using the time-of-flight technique. A lead sample with natural isotopic composition was used. NE213 liquid scintillation detectors with well-known detection efficiencies were used for the detection of the scattered neutrons. Angle-integrated cross sections were determined by a Legendre polynomial expansion using least-squares methods. Additionally, measurements were carried out for isotopically pure 209 Bi and 181 Ta samples at 4 MeV incident neutron energy. Results are compared with other

Proceedings of the Fourth Compton Symposium. Proceedings

International Nuclear Information System (INIS)

Dermer, C.D.; Strickman, M.S.; Kurfess, J.D.

1997-01-01

These proceedings represent the papers presented at the Fourth Compton Symposium held in Williamsburg, Virginia in April, 1997. This symposium gives the latest development in gamma ray astronomy and summarizes the results obtained by the Compton Gamma Ray Observatory. One of the missions of the Observatory has been the study of physical processes taking place in the most dynamic sites in the Universe, including supernovae, novae, pulsars, black holes, active galaxies, and gamma-ray bursts. The energies covered range from hard X-ray to gamma-ray regions from 15 KeV to 30 GeV. The Burst and Transient Experiment (BASTE) measures brightness variations in gamma-ray bursts and solar flares. The Oriented Scintillation Spectroscopy Experiment (OSSE), measures spectral output of astrophysical sources in the 0.05 to 10 MeV range. The Imaging Compton Telescope (COMPTEL) detects gamma-rays and performs sky survey in the energy range 1 to 30 MeV. The Energetic Gamma Ray Experiment Telescope (EGRET) covers the broadest energy range from 20 MeV to 30 GeV. The papers presented result from all of the above. There were 249 papers presented and out of these, 6 have been abstracted for the Energy, Science and Technology database

Inclusive. pi. /sup 0/ production by e/sup +/e/sup -/ annihilation at 34. 6 GeV center of mass energy

Energy Technology Data Exchange (ETDEWEB)

Braunschweig, W; Gerhards, R; Kirschfink, F J; Martyn, H U; Rosskamp, P; Vogel, E; Wallraff, W; Bock, B; Eisenmann, J; Fischer, H M

1986-11-01

The cross section for the process e/sup +/e/sup -/->..pi../sup 0/ + anything has been measured at an average Center of mass energy of 34.6 GeV for ..pi../sup 0/ energies between 0.7 and 17 GeV. The angular distribution for ..pi../sup 0/ energies larger than 2 GeV is of the form dsigma/d..cap omega..propor to1 + A cos/sup 2/theta, with A = 1.2+-0.5. The ratio of ..pi../sup 0/ to ..pi../sup +-/ production in the measured energy range is 2sigma(..pi../sup 0/)/(sigma(..pi../sup +/)+sigma(..pi../sup -/)) = 1.13+-0.18. The form of the differential cross sections agrees within the errors. The mean ..pi../sup 0/ multiplicity is 5.8+-0.9.

Inter-comparison of High Energy Files (neutron-induced, from 20 to 150 MeV)

Energy Technology Data Exchange (ETDEWEB)

Lee, Young-Ouk; Fukahori, Tokio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1998-11-01

Recent new applications using accelerator-driven system require well-tested nuclear data when modeling the interaction of neutrons above 20 MeV. This work is aimed to review evaluation methods applied in currently available neutron high energy files above 20 to 150 MeV, to inter-compare their evaluated cross sections on some important isotopes, and to analyze resulting discrepancies. Through out these, integrities and consistencies of the high energy files are checked, applicability of physics models and evaluation methodologies are assessed, and some directions are derived to improve and expand current JENDL High Energy File. (author)

Four-jet final state production in $e^+ e^-$ collisions at centre-of-mass energies ranging from 130 to 184 GeV

CERN Document Server

Barate, R; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Nief, J Y; Pietrzyk, B; Boix, G; Casado, M P; Chmeissani, M; Crespo, J M; Delfino, M C; Fernández, E; Fernández-Bosman, M; Garrido, L; Graugès-Pous, E; Juste, A; Martínez, M; Merino, G; Miquel, R; Mir, L M; Morawitz, P; Park, I C; Pascual, A; Perlas, J A; Riu, I; Sánchez, F; Colaleo, A; Creanza, D; De Palma, M; Gelao, G; Iaselli, Giuseppe; Maggi, G; Maggi, M; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Abbaneo, D; Alemany, R; Becker, U; Bright-Thomas, P G; Casper, David William; Cattaneo, M; Cerutti, F; Ciulli, V; Dissertori, G; Drevermann, H; Forty, Roger W; Frank, M; Gianotti, F; Hagelberg, R; Hansen, J B; Harvey, J; Janot, P; Jost, B; Lehraus, Ivan; Mato, P; Minten, Adolf G; Moneta, L; Pacheco, A; Pusztaszeri, J F; Ranjard, F; Rolandi, Luigi; Rousseau, D; Schlatter, W D; Schmitt, M; Schneider, O; Tejessy, W; Teubert, F; Tomalin, I R; Vreeswijk, M; Wachsmuth, H W; Wagner, A; Ajaltouni, Ziad J; Badaud, F; Chazelle, G; Deschamps, O; Falvard, A; Ferdi, C; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rosnet, P; Fearnley, Tom; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Daskalakis, G; Kyriakis, A; Markou, C; Simopoulou, Errietta; Vayaki, Anna; Blondel, A; Brient, J C; Machefert, F P; Rougé, A; Rumpf, M; Valassi, Andrea; Videau, H L; Boccali, T; Focardi, E; Parrini, G; Zachariadou, K; Cavanaugh, R J; Corden, M; Georgiopoulos, C H; Hühn, T; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Curtis, L; Dorris, S J; Halley, A W; Lynch, J G; Negus, P; O'Shea, V; Raine, C; Scarr, J M; Smith, K; Teixeira-Dias, P; Thompson, A S; Thomson, E; Thomson, F; Ward, J; Buchmüller, O L; Dhamotharan, S; Geweniger, C; Graefe, G; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Sommer, J; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Girone, M; Goodsir, S M; Martin, E B; Marinelli, N; Moutoussi, A; Nash, J; Sedgbeer, J K; Spagnolo, P; Williams, M D; Ghete, V M; Girtler, P; Kneringer, E; Kuhn, D; Rudolph, G; Betteridge, A P; Bowdery, C K; Buck, P G; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Jones, R W L; Whelan, E P; Williams, M I; Giehl, I; Hoffmann, C; Jakobs, K; Kleinknecht, K; Quast, G; Renk, B; Rohne, E; Sander, H G; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Benchouk, C; Bonissent, A; Bujosa, G; Carr, J; Coyle, P; Ealet, A; Fouchez, D; Leroy, O; Motsch, F; Payre, P; Talby, M; Sadouki, A; Thulasidas, M; Tilquin, A; Trabelsi, K; Aleppo, M; Antonelli, M; Ragusa, F; Berlich, R; Blum, Walter; Büscher, V; Dietl, H; Ganis, G; Gotzhein, C; Kroha, H; Lütjens, G; Lutz, Gerhard; Mannert, C; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Stenzel, H; Wiedenmann, W; Wolf, G; Boucrot, J; Callot, O; Chen, S; Davier, M; Duflot, L; Grivaz, J F; Höcker, A; Jacholkowska, A; Kado, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Schune, M H; Serin, L; Tournefier, E; Veillet, J J; Videau, I; Zerwas, D; Azzurri, P; Bagliesi, G; Bettarini, S; Bozzi, C; Calderini, G; Dell'Orso, R; Fantechi, R; Ferrante, I; Giassi, A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Rizzo, G; Sanguinetti, G; Sciabà, A; Sguazzoni, G; Steinberger, Jack; Tenchini, Roberto; Vannini, C; Venturi, A; Verdini, P G; Blair, G A; Bryant, L M; Chambers, J T; Coles, J; Green, M G; Medcalf, T; Perrodo, P; Strong, J A; Von Wimmersperg-Töller, J H; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Maley, P; Norton, P R; Thompson, J C; Wright, A E; Bloch-Devaux, B; Colas, P; Fabbro, B; Faïf, G; Lançon, E; Lemaire, M C; Locci, E; Pérez, P; Przysiezniak, H; Rander, J; Renardy, J F; Rosowsky, A; Roussarie, A; Trabelsi, A; Vallage, B; Black, S N; Dann, J H; Kim, H Y; Konstantinidis, N P; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Brew, C A J; Cartwright, S L; Combley, F; Kelly, M S; Lehto, M H; Reeve, J; Thompson, L F; Affholderbach, K; Böhrer, A; Brandt, S; Cowan, G D; Foss, J; Grupen, Claus; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Musolino, G; Pütz, J; Rothberg, J E; Wasserbaech, S R; Williams, R W; Armstrong, S R; Charles, E; Elmer, P; Ferguson, D P S; Gao, Y; González, S; Greening, T C; Hayes, O J; Hu, H; Jin, S; McNamara, P A; Nachtman, J M; Nielsen, J; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Walsh, J; Wu Sau Lan; Wu, X; Yamartino, J M; Zobernig, G

1998-01-01

The four jet topology is analysed in the ALEPH data taken between November 1995 and November 1997, at centre-of-mass energies ranging from 130 to 184 GeV. While an unexpected accumulation of events with a dijet mas sum around 105 GeV/c**2 had been observed during the first run in 1995 at 130/136 GeV, corresponding to an integrated luminosity of 5.7 pb-1, no significant differences between data and standard model prediction is noticed, either in the high energy runs (81.1 pb-1 taken at centre-of-mass energies from 161 to 184 GeV) or in the 7.1 pb-1 recorded during a new short run at 130/136 GeV in 1997. We have found no other explanation for the earlier reported ``four jet anomaly'' than a statistical fluctuation.

Four-jet final state production in e+e- collisions at centre-of-mass energies ranging from 130 to 184 GeV

Science.gov (United States)

ALEPH Collaboration; Barate, R.; Buskulic, D.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Lucotte, A.; Minard, M.-N.; Nief, J.-Y.; Pietrzyk, B.; Boix, G.; Casado, M. P.; Chmeissani, M.; Crespo, J. M.; Delfino, M.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, Ll.; Graugès, E.; Juste, A.; Martinez, M.; Merino, G.; Miquel, R.; Mir, Ll. M.; Morawitz, P.; Park, I. C.; Pascual, A.; Perlas, J. A.; Riu, I.; Sanchez, F.; Colaleo, A.; Creanza, D.; de Palma, M.; Gelao, G.; Iaselli, G.; Maggi, G.; Maggi, M.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Alemany, R.; Becker, U.; Bright-Thomas, P.; Casper, D.; Cattaneo, M.; Cerutti, F.; Ciulli, V.; Dissertori, G.; Drevermann, H.; Forty, R. W.; Frank, M.; Gianotti, F.; Hagelberg, R.; Hansen, J. B.; Harvey, J.; Janot, P.; Jost, B.; Lehraus, I.; Mato, P.; Minten, A.; Moneta, L.; Pacheco, A.; Pusztaszeri, J.-F.; Ranjard, F.; Rolandi, L.; Rousseau, D.; Schlatter, D.; Schmitt, M.; Schneider, O.; Tejessy, W.; Teubert, F.; Tomalin, I. R.; Vreeswijk, M.; Wachsmuth, H.; Wagner, A.; Ajaltouni, Z.; Badaud, F.; Chazelle, G.; Deschamps, O.; Falvard, A.; Ferdi, C.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Rosnet, P.; Fearnley, T.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Nilsson, B. S.; Rensch, B.; Wäänänen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Vayaki, A.; Blondel, A.; Brient, J.-C.; Machefert, F.; Rougé, A.; Rumpf, M.; Valassi, A.; Videau, H.; Boccali, T.; Focardi, E.; Parrini, G.; Zachariadou, K.; Cavanaugh, R.; Corden, M.; Georgiopoulos, C.; Huehn, T.; Jaffe, D. E.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Dorris, S. J.; Halley, A. W.; Lynch, J. G.; Negus, P.; O'Shea, V.; Raine, C.; Scarr, J. M.; Smith, K.; Teixeira-Dias, P.; Thompson, A. S.; Thomson, E.; Thomson, F.; Buchmüller, O.; Dhamotharan, S.; Geweniger, C.; Graefe, G.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E. E.; Putzer, A.; Sommer, J.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Dornan, P. J.; Girone, M.; Goodsir, S.; Martin, E. B.; Marinelli, N.; Moutoussi, A.; Nash, J.; Sedgbeer, J. K.; Spagnolo, P.; Williams, M. D.; Ghete, V. M.; Girtler, P.; Kneringer, E.; Kuhn, D.; Rudolph, G.; Betteridge, A. P.; Bowdery, C. K.; Buck, P. G.; Colrain, P.; Crawford, G.; Finch, A. J.; Foster, F.; Hughes, G.; Jones, R. W. L.; Whelan, E. P.; Williams, M. I.; Giehl, I.; Hoffmann, C.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.-G.; van Gemmeren, P.; Zeitnitz, C.; Aubert, J. J.; Benchouk, C.; Bonissent, A.; Bujosa, G.; Carr, J.; Coyle, P.; Ealet, A.; Fouchez, D.; Leroy, O.; Motsch, F.; Payre, P.; Talby, M.; Sadouki, A.; Thulasidas, M.; Tilquin, A.; Trabelsi, K.; Aleppo, M.; Antonelli, M.; Ragusa, F.; Berlich, R.; Blum, W.; Büscher, V.; Dietl, H.; Ganis, G.; Gotzhein, C.; Kroha, H.; Lütjens, G.; Lutz, G.; Mannert, C.; Männer, W.; Moser, H.-G.; Richter, R.; Rosado-Schlosser, A.; Schael, S.; Settles, R.; Seywerd, H.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Boucrot, J.; Callot, O.; Chen, S.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Höcker, A.; Jacholkowska, A.; Kado, M. M.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Schune, M.-H.; Serin, L.; Tournefier, E.; Veillet, J.-J.; Videau, I.; Zerwas, D.; Azzurri, P.; Bagliesi, G.; Bettarini, S.; Bozzi, C.; Calderini, G.; dell'Orso, R.; Fantechi, R.; Ferrante, I.; Giassi, A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Sciabà, A.; Sguazzoni, G.; Steinberger, J.; Tenchini, R.; Vannini, C.; Venturi, A.; Verdini, P. G.; Blair, G. A.; Bryant, L. M.; Chambers, J. T.; Coles, J.; Green, M. G.; Medcalf, T.; Perrodo, P.; Strong, J. A.; von Wimmersperg-Toeller, J. H.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Haywood, S.; Maley, P.; Norton, P. R.; Thompson, J. C.; Wright, A. E.; Bloch-Devaux, B.; Colas, P.; Fabbro, B.; Faïf, G.; Lançon, E.; Lemaire, M.-C.; Locci, E.; Perez, P.; Przysiezniak, H.; Rander, J.; Renardy, J.-F.; Rosowsky, A.; Roussarie, A.; Trabelsi, A.; Vallage, B.; Black, S. N.; Dann, J. H.; Kim, H. Y.; Konstantinidis, N.; Litke, A. M.; McNeil, M. A.; Taylor, G.; Booth, C. N.; Brew, C. A. J.; Cartwright, S.; Combley, F.; Kelly, M. S.; Lehto, M.; Reeve, J.; Thompson, L. F.; Affholderbach, K.; Böhrer, A.; Brandt, S.; Cowan, G.; Foss, J.; Grupen, C.; Smolik, L.; Stephan, F.; Apollonio, M.; Bosisio, L.; della Marina, R.; Giannini, G.; Gobbo, B.; Musolino, G.; Putz, J.; Rothberg, J.; Wasserbaech, S.; Williams, R. W.; Armstrong, S. R.; Charles, E.; Elmer, P.; Ferguson, D. P. S.; Gao, Y.; González, S.; Greening, T. C.; Hayes, O. J.; Hu, H.; Jin, S.; McNamara, P. A., III; Nachtman, J. M.; Nielsen, J.; Orejudos, W.; Pan, Y. B.; Saadi, Y.; Scott, I. J.; Walsh, J.; Wu, Sau Lan; Wu, X.; Yamartino, J. M.; Zobernig, G.

1998-02-01

The four jet topology is analysed in the ALEPH data taken between November 1995 and October 1997, at centre-of-mass energies ranging from 130 to 184 GeV. While an unexpected accumulation of events with a dijet mass sum around 105 GeV/c2 had been observed during the first run in 1995 at 130/136 GeV, corresponding to an integrated luminosity of 5.7 pb-1, no significant differences between data and standard model prediction is seen, either in the high energy runs (81.1 pb-1 taken at centre-of-mass energies from 161 to 184 GeV) or in the 7.1 pb-1 recorded during a new short run at 130/136 GeV in 1997. We have found no other explanation for the earlier reported ``four jet anomaly'' than a statistical fluctuation.

Calibration of a large multi-element neutron counter in the energy range 85-430 MeV

CERN Document Server

Strong, J A; Esterling, R J; Garvey, J; Green, M G; Harnew, N; Jane, M R; Jobes, M; Mawson, J; McMahon, T; Robertson, A W; Thomas, D H

1978-01-01

Describes the calibration of a large 60 element neutron counter with a threshold of 2.7 MeV equivalent electron energy. The performance of the counter has been measured in the neutron kinetic energy range 8.5-430 MeV using a neutron beam at the CERN Synchrocyclotron. The results obtained for the efficiency as a function of energy are in reasonable agreement with a Monte Carlo calculation. (7 refs).

LRSPC, Proton High-Energy Loss in Matter

International Nuclear Information System (INIS)

2001-01-01

1 - Description of program or function: The LRSPC program is designed to estimate the energy loss, due to ionization and excitation, and the range of charged particles passing through matter. The code treats protons in elements or mixtures composed of elements with atomic numbers ranging from 1 to 100. The results for protons are generally valid from 1 MeV to 100 GeV. The code may be extended to treat other charged particles such as muons, pions, hyperons, deuterons, tritons and alphas by changing the particle mass, charge and range at 2 MeV. 2 - Method of solution: Stopping power is calculated from the Bethe-Bloch equation with shell and density corrections included. Range is calculated by integrating the reciprocal of the stopping power from an initial value at 2 MeV. The K-shell correction is taken from Walske's data. The L-shell and higher shell corrections are adjusted to fit low energy measurements fro 30 elements. The density correction is calculated by a method similar to that of Sternheimer, differing chiefly in the large number of electron shells considered. LRSPC computes improved proton range and stopping power data for use in the proton penetration code, LPPC (CCC-0051). It is packages separately and may be requested independently. 3 - Restrictions on the complexity of the problem: Number of elements in mixture ≤ 10, Atomic number of element ≤ 100, Number of energy points ≤ 500

Analyses of Alpha-Alpha Elastic Scattering Data in the Energy Range 140 - 280 MeV

Energy Technology Data Exchange (ETDEWEB)

Shehadeh, Zuhair F. [Taif University, Taif (Saudi Arabia)

2017-01-15

The differential and the reaction cross-sections for 4He-4He elastic scattering data have been nicely obtained at four energies ranging from 140 MeV to 280 MeV (lab system), namely, 140, 160, 198 and 280 MeV, by using a new optical potential with a short-range repulsive core. The treatment has been handled relativistically as υ/c > 0.25 for the two lower energies and υ/c > 0.31 for the two higher ones. In addition to explaining the elastic angular distributions, the adopted potentials accounted for the structure that may exist at angles close to 90◦ , especially for the 198 and the 280-MeV incident energies. No renormalization has been used, and all our potential parameters are new. The necessity of including a short-range repulsive potential term in our real nuclear potential part has been demonstrated. Our results contribute to solving a long-standing problem concerning the nature of the alpha-alpha potential. This is very beneficial in explaining unknown alpha-nucleus and nucleus-nucleus relativistic reactions by using the cluster formalism.

Direct determination of k Q factors for cylindrical and plane-parallel ionization chambers in high-energy electron beams from 6 MeV to 20 MeV

Science.gov (United States)

Krauss, A.; Kapsch, R.-P.

2018-02-01

For the ionometric determination of the absorbed dose to water, D w, in high-energy electron beams from a clinical accelerator, beam quality dependent correction factors, k Q, are required. By using a water calorimeter, these factors can be determined experimentally and potentially with lower standard uncertainties than those of the calculated k Q factors, which are tabulated in various dosimetry protocols. However, one of the challenges of water calorimetry in electron beams is the small measurement depths in water, together with the steep dose gradients present especially at lower energies. In this investigation, water calorimetry was implemented in electron beams to determine k Q factors for different types of cylindrical and plane-parallel ionization chambers (NE2561, NE2571, FC65-G, TM34001) in 10 cm  ×  10 cm electron beams from 6 MeV to 20 MeV (corresponding beam quality index R 50 ranging from 1.9 cm to 7.5 cm). The measurements were carried out using the linear accelerator facility of the Physikalisch-Technische Bundesanstalt. Relative standard uncertainties for the k Q factors between 0.50% for the 20 MeV beam and 0.75% for the 6 MeV beam were achieved. For electron energies above 8 MeV, general agreement was found between the relative electron energy dependencies of the k Q factors measured and those derived from the AAPM TG-51 protocol and recent Monte Carlo-based studies, as well as those from other experimental investigations. However, towards lower energies, discrepancies of up to 2.0% occurred for the k Q factors of the TM34001 and the NE2571 chamber.

Direct determination of k Q factors for cylindrical and plane-parallel ionization chambers in high-energy electron beams from 6 MeV to 20 MeV.

Science.gov (United States)

Krauss, A; Kapsch, R-P

2018-02-06

For the ionometric determination of the absorbed dose to water, D w , in high-energy electron beams from a clinical accelerator, beam quality dependent correction factors, k Q , are required. By using a water calorimeter, these factors can be determined experimentally and potentially with lower standard uncertainties than those of the calculated k Q factors, which are tabulated in various dosimetry protocols. However, one of the challenges of water calorimetry in electron beams is the small measurement depths in water, together with the steep dose gradients present especially at lower energies. In this investigation, water calorimetry was implemented in electron beams to determine k Q factors for different types of cylindrical and plane-parallel ionization chambers (NE2561, NE2571, FC65-G, TM34001) in 10 cm  ×  10 cm electron beams from 6 MeV to 20 MeV (corresponding beam quality index R 50 ranging from 1.9 cm to 7.5 cm). The measurements were carried out using the linear accelerator facility of the Physikalisch-Technische Bundesanstalt. Relative standard uncertainties for the k Q factors between 0.50% for the 20 MeV beam and 0.75% for the 6 MeV beam were achieved. For electron energies above 8 MeV, general agreement was found between the relative electron energy dependencies of the k Q factors measured and those derived from the AAPM TG-51 protocol and recent Monte Carlo-based studies, as well as those from other experimental investigations. However, towards lower energies, discrepancies of up to 2.0% occurred for the k Q factors of the TM34001 and the NE2571 chamber.

Production of positive pions from polarized protons by linearly polarized photons in the energy region 300--420 MeV

Energy Technology Data Exchange (ETDEWEB)

Get' man, V.A.; Gorbenko, V.G.; Grushin, V.F.; Derkach, A.Y.; Zhebrovskii, Y.V.; Karnaukhov, I.M.; Kolesnikov, L.Y.; Luchanin, A.A.; Rubashkin, A.L.; Sanin, V.M.; Sorokin, P.V.; Sporov, E.A.; Telegin, Y.N.; Shalatskii, S.V.

1980-10-01

A technique for measurement of the polarization observables ..sigma.., P, and T for the reaction ..gamma..p..-->..n..pi../sup +/ in a doubly polarized experiment (polarized proton target + linearly polarized photon beam) is described. Measurements of the angular distributions of these observables in the range of pion emission angles 30--150/sup 0/ are presented for four photon energies from 300 to 420 MeV. Inclusion of the new experimental data in an energy-independent multipole analysis of photoproduction from protons permits a more reliable selection of solutions to be made.

A machine learning method to separate cosmic ray electrons from protons from 10 to 100 GeV using DAMPE data

Science.gov (United States)

Zhao, Hao; Peng, Wen-Xi; Wang, Huan-Yu; Qiao, Rui; Guo, Dong-Ya; Xiao, Hong; Wang, Zhao-Min

2018-06-01

DArk Matter Particle Explorer (DAMPE) is a general purpose high energy cosmic ray and gamma ray observatory, aiming to detect high energy electrons and gammas in the energy range 5 GeV to 10 TeV and hundreds of TeV for nuclei. This paper provides a method using machine learning to identify electrons and separate them from gammas, protons, helium and heavy nuclei with the DAMPE data acquired from 2016 January 1 to 2017 June 30, in the energy range from 10 to 100 GeV.

High-energy gamma-rays from Cyg X-1

Science.gov (United States)

Zdziarski, Andrzej A.; Malyshev, Denys; Chernyakova, Maria; Pooley, Guy G.

2017-11-01

We have obtained a firm detection of Cyg X-1 during its hard and intermediate spectral states in the energy range of 40 MeV-60 GeV based on observations by the Fermi Large Area Telescope, confirming the independent results at ≥60 MeV of a previous work. The detection significance is ≃8σ in the 0.1-10 GeV range. In the soft state, we have found only upper limits on the emission at energies ≳0.1 MeV. However, we have found emission with a very soft spectrum in the 40-80 MeV range, not detected previously. This is likely to represent the high-energy cut-off of the high-energy power-law tail observed in the soft state. Similarly, we have detected a γ-ray soft excess in the hard state, which appears to be of similar origin. We have also confirmed the presence of an orbital modulation of the detected emission in the hard state, expected if the γ-rays are from Compton upscattering of stellar blackbody photons. However, the observed modulation is significantly weaker than that predicted if the blackbody upscattering were the dominant source of γ-rays. This argues for a significant contribution from γ-rays produced by the synchrotron self-Compton process. We have found that such strong contribution is possible if the jet is strongly clumped. We reproduce the observed hard-state average broad-band spectrum using a self-consistent jet model, taking into account all the relevant emission processes, e± pair absorption and clumping. This model also reproduces the amplitude of the observed orbital modulation.

Neutron scattering on natural iron at incident energies between 9.4 and 15.2 MeV

International Nuclear Information System (INIS)

Schmidt, D.; Mannhart, W.; Klein, H.; Nolte, R.

1994-11-01

Neutrons were scattered on a sample of natural iron at 12 incident energies in the range between 9.4 MeV and 15.2 MeV. Differential cross sections of the elastic scattering (natural iron) and of the inelastic scattering to the first excited level of 56 Fe (Q=-0.847 MeV) were determined for angles between 12.5 deg and 160 deg with total uncertainties between of 3% and 10%. Legendre polynomial least-squares fits resulted in integrated cross sections with uncertainties of 2% (elastic data) and 7% (inelastic data). The cross sections obtained in this work were compared with data from the literature. Inelastic scattering cross sections were determined within the scope of a pseudolevel analysis up to excitation energies of nearly 5.5 MeV. At higher excitation energies the scattering spectrum is contaminated by scattered breakup neutrons from the D+d source used hampering an analysis of the data. (orig.) [de

Measurement of the energy spectrum with proportional counters with spherical cathodes between 20 keV and 2.5 MeV with the propagation of 14 MeV neutrons in liquid nitrogen and liquid air

International Nuclear Information System (INIS)

Schneider-Kuehnle, P.

1974-01-01

This work deals with the measurement of the energy spectrum of a 14 MeV neutron source in liquid nitrogen and liquid air in the energy region of 20 keV to 2.5 MeV as a function of the distance from the source. The measured results together with those of a scintispectrometer which measures the energies between 2.5 MeV and 14 MeV, are to serve as experimentally-supported input data for shielding calculations and are to enable the checking of transport theoretical calculations. (orig./LH) [de

Three-fold increase of M1 strength in 40Ar at 10 MeV excitation energy

Science.gov (United States)

Tornow, Werner; Finch, Sean; Krishichayan, Fnu; Tonchev, Anton

2017-09-01

We reexamined the excitation energy region of 40Ar around 9.8 MeV with the goal of determining the known M1 strength located at 9.76 MeV more accurately. The physics motivation was based on the fact that i) the neutrino-nucleus interaction cross section is proportional to the M1 strength of a nucleus, ii) DUNE, the Deep Underground Neutrino Experiment at SURF will be using liquid argon as detector medium, iii) the energy spectrum of supernova neutrinos is peaked at approximately 10 MeV. Mono-energetic and linearly polarized photons of 9.88 MeV were produced via Compton backscattering of 548 nm FEL photons from 543 MeV electrons at the High-Intensity γ-ray Source (HI γS) facility at TUNL. The 1.25 cm diameter photon beam with energy spread of 300 keV (FWHM) interacted with argon gas contained in a high-pressure cell. The cell was viewed with HPGe detectors placed at 90o relative to the incident photon beam in the horizontal and vertical planes to distinguish between E1 and M1 de-excitation γ-rays. Our re-measurement provided an increase in M1 strength by a factor of approximately 3, mostly due to the discovery that the known level in 40Ar at 9.84 MeV is of M1 character and not of E1 character, as previously thought. In addition to the already known M1 state at 9.76 MeV, we observed weaker M1 states at 9.70, 9.81, 9.87, and 9.89 MeV.

Investigation of the neutron-proton-interaction in the energy range from 20 to 50 MEV

International Nuclear Information System (INIS)

Wilczynski, J.

1984-07-01

In the framework of the investigation of the isospin singlet part of the nucleon-nucleon-interaction in the energy range below 100 MeV two experiments were conducted, which were selected by sensitivity calculations. At the Karlsruhe polarized neutron facility POLKA the analyzing powers Asub(y) and Asub(yy) of the elastic n vector-p- and n vector-p vector-scattering were measured in the energy range from 20 to 50 MeV. The results of this epxeriment are compared to older data. In the energy range from 20 to 50 MeV the new data were analyzed together with other selected data of the nucleon-nucleon-system in phase shift analyses. The knowledge of the isospin singlet phase shifts 1 P 1 and 3 D 3 was improved by the new data. (orig./HSI) [de

Gamma-ray astronomy in the medium energy (10-50 MeV) range

International Nuclear Information System (INIS)

Kniffen, D.A.; Bertsch, D.L.; Palmeira, R.A.R.; Rao, K.R.

1977-01-01

Gamma-ray astronomy in the medium energy (10-50 MeV) range can provide unique information with which to study many astrophysical problems. Observations in the 10-50 MeV range provide the cleanest window with which to view the isotropic diffuse component of the radiation and to study the possible cosmological implications of the spectrum. For the study of compact sources, this is the important region between the X-ray sky and the vastly different γ-ray sky seen by SAS-2 and COS-B. To understand the implications of medium energy γ-ray astronomy to the study of the galactic diffuse γ-radiation, the model developed to explain the high energy γ-ray observations of SAS-2 is extended to the medium energy range. This work illustrates the importance of medium energy γ-ray astronomy for studying the electromagnetic component of the galactic cosmic rays. To observe the medium energy component of the intense galactic center γ-ray emission, two balloon flights of a medium energy γ-ray spark chamber telescope were flown in Brazil in 1975. These results indicate the emission is higher than previously thought and above the predictions of the theoretical model

Elastic scattering of 7Li + 27Al at several angles in the 7-11 MeV energy range

International Nuclear Information System (INIS)

Abriola, D.; Carnelli, P.; Arazi, A.; Figueira, J.M.; Capurro, O.A.; Cardona, M.A.; Fernandez Niello, J.O.; Hojman, D.; Fimiani, L.; Grinberg, P.; Martinez Heimann, D.; Marti, G.V.; Negri, A.E.; Pacheco, A.J.

2010-01-01

Elastic cross sections for the 7 Li + 27 Al system were measured at laboratory energies between 7 and 11 MeV in steps of 0.25 MeV, and angles between 135 o and 170 o in steps of 5 o . Excitation functions for the elastic scattering were measured using an array of eight Si surface-barrier detectors whereas a solid-state telescope was used to estimate and subtract background from other reactions. Contamination from α particles arising from the 7 Li breakup process at E lab ≥ 10 MeV makes the use of these energies inadvisable for RBS applications. The present results are compared with previous data obtained at 165 o (E lab ≤ 6 MeV), 140 o and 170 o (E lab ≤ 8 MeV). The experimental data were analyzed in terms of the Optical Model. Two different energy-independent potentials were found. These optical potentials allow an interpolation with physical meaning to other energies and scattering angles. The experimental cross sections will be uploaded to the IBANDL database.

Effect of free-particle collisions in high energy proton and pion-induced nuclear reactions

International Nuclear Information System (INIS)

Jacob, N.P. Jr.

1975-07-01

The effect of free-particle collisions in simple ''knockout'' reactions of the form (a,aN) and in more complex nuclear reactions of the form (a,X) was investigated by using protons and pions. Cross sections for the 48 Ti(p,2p) 47 Sc and the 74 Ge(p,2p) 73 Ga reactions were measured from 0.3 to 4.6 GeV incident energy. The results indicate a rise in (p,2p) cross section for each reaction of about (25 +- 3) percent between the energies 0.3 and 1.0 GeV, and are correlated to a large increase in the total free-particle pp scattering cross sections over the same energy region. Results are compared to previous (p,2p) excitation functions in the GeV energy region and to (p,2p) cross section calculations based on a Monte Carlo intranuclear cascade-evaporation model. Cross section measurements for (π/sup +-/, πN) and other more complex pion-induced spallation reactions were measured for the light target nuclei 14 N, 16 O, and 19 F from 45 to 550 MeV incident pion energy. These measurements indicate a broad peak in the excitation functions for both (π,πN) and (π,X) reactions near 180 MeV incident energy. This corresponds to the large resonances observed in the free-particle π + p and π - p cross sections at the same energy. Striking differences in (π,πN) cross section magnitudes are observed among the light nuclei targets. The experimental cross section ratio sigma(π - ,π - n)/sigma(π + ,πN) at 180 MeV is 1.7 +- 0.2 for all three targets. The experimental results are compared to previous pion and analogous proton-induced reactions, to Monte Carlo intranuclear cascade-evaporation calculations, and to a semi-classical nucleon charge exchange model. (108 references) (auth)

Two-body photodisintegration of the deuteron from 100 to 800 MeV

Energy Technology Data Exchange (ETDEWEB)

Crawford, R.; Ahrens, J.; Altieri, S.; Annand, J.R.M.; Anthony, I.; Audit, G.; Beck, R.; Braghieri, A.; D`Hose, N.; Hall, S.; Isbert, V.; Kellie, J.D.; Kerhoas, S.; MacCormick, M.; MacGeorge, J.C.; Medaglia, R.; Miller, G.J.; Murphy, L.Y.; Owens, R.O.; Pedroni, P.; Pinelli, T.; Tamas, G.; Wallace, P.A. [Glasgow Univ. (United Kingdom). Dept. of Phys. and Astron.]|[Mainz Univ. (Germany). Inst. fuer Kernphys.]|[INFN, Sezione di Pavia (Italy)]|[Pavia Univ. (Italy). Dipartimento di Fisica Nucleare e Teorica]|[CEA-DAPNIA/SPhN, 91 - Gif-sur-Yvette (France)

1996-06-24

The total and the differential cross sections for the D({gamma},p)n reaction have been measured over the photon energy range 100-800 MeV at the 855 MeV MAMI Microtron in Mainz. Using the large acceptance detector DAPHNE in conjunction with the Glasgow tagging spectrometer, high precision results with small systematic errors were obtained. The data are presented in the form of thirty-five angular distributions at c.m. proton angles between 30 {sup circle} -160 {sup circle} in 10 {sup circle} intervals and at photon energies in steps of 20 MeV. Previous experimental work is reassessed in the light of the present results and comparison with some recent theoretical calculations. (orig.).

Determination of alpha/sub s/ from energy-energy correlations in e+e- annihilation at 29 GeV

International Nuclear Information System (INIS)

Wood, D.R.

1987-10-01

We have studied the energy-energy correlation in e + e - annihilation into hadrons at √s = 29 GeV using the Mark II detector at PEP. We find to O(α/sub s/ 2 ) that α/sub s/ = 0.158 +- .003 +- .008 if hadronization is described by string fragmentation. Independent fragmentation schemes give α/sub s/ = .10 - .14, and give poor agreement with the data. A leading-log shower fragmentation model is found to describe the data well

5@5 - A 5 GeV Energy Threshold Array of Imaging Atmospheric Cherenkov Telescopes at 5 km Altitude

Science.gov (United States)

Aharonian, F. A.; Konopelko, A. K.; Voelk, H. J.; Quintana, H.

2000-10-01

We discuss the concept and the performance of 5@5 - a stereoscopic array of several large imaging atmospheric Cherenkov telescopes installed at a very high mountain elevation of about 5 km a.s.l. or more - for the study of the gamma-ray sky at energies from several GeV to 100 GeV. With its capability to detect the ``standard'' EGRET sources with spectra extending up to 10 GeV in exposure times from 1 to 103 seconds, such a detector may serve as an ideal "Gamma-Ray Timing Explorer" for the study of transient non-thermal phenomena like gamma-radiation from AGN jets, synchrotron flares of microquasars, the high energy (GeV) counterparts of Gamma Ray Bursts, etc. Such an instrument would also allow detailed studies of the spectral characteristics of persistent gamma-ray sources like pulsars, supernova remnants, plerions, radiogalaxies, etc, in the energy region between 10 GeV and 100 GeV, where the capabilities of both the current space-based and ground-based gamma-ray projects are quite limited. The existing technological achievements in the design and construction of multi (1000) pixel, high resolution imagers, as well as of large, 20 m diameter class multi-mirror dishes with rather modest optical requirements, would allow the construction of the "5@5" in a foreseeable future. The Llano de Chajnantor (or the neighboring Cerro Toco) in the Atacama desert of Northern Chile seems an ideal site for such a ``post - CANGAROO/H.E.S.S./MAGIC/VERITAS'' era ground-based gamma-ray detector. The large flat area of that site, which was recently chosen for the installation of one of the most powerful future astronomical instruments - the Atacama Large Millimeter Array (ALMA) - could accomodate also an additional Cherenkov telescope array which requires a relatively compact area with a radius of about 100 m.

The reaction 32S(d,alpha)30P

International Nuclear Information System (INIS)

Lawrie, J.J.

1979-03-01

Cross sections for the reaction 32 S(d,alpha) 30 P were measured at an average deuteron energy of about 6 MeV over deuteron energy ranges of about 200 - 400 KeV with steps of 15 KeV and at laboratory angles of 90 degrees, 112 degrees, 125 degrees, 133 degrees, 137 degrees, 141 degrees, 148 degrees, 155 degrees and 175,5 degrees. The range of excitation pertaining to the study, extended to the 23rd excited state at 4,73 MeV in 30 P. The observed cross section fluctuations in the excitation functions are indicative of the statistical nature of the reaction. A coherence width of 43 plus minus 4 keV was obtained for the compound nucleus 34 Cl at 17,2 MeV excitation from fluctuation analyses for states up to the 7th excited level at 2,84 MeV in 30 P. By contrast the coherence width for the isospin forbidden transition to the T = 1 excited state at 2,94 MeV in 30 P was found to be 34 plus minus 6 keV. This difference can be accounted for in terms of isospin mixing in the compound nucleus. Spins of excited states in 30 P were determined by comparing experimental cross sections with Hauser-Feshbach predictions. The most probable spin values obtained from this study are: 1 + for the 10th (3,73 MeV),2 + for the 11th (3,83 MeV),3 + for the 12th (3,93 MeV),0 + for the 16th (4,235 MeV) and 1 + for the 23rd excited state at 4,73 MeV in 30 P. From the assumption that the spin of the 17th excited state (4,30 MeV) is 2 - , spin possibilities of 2 + , 3 - and 4 + could be deduced for the 18th excited state (4,34 MeV). An inhibition factor of 0,41 plus minus 0,06 for the isospin forbidden reaction 32 S(d,alpha) 30 P has been obtained and corresponds to a value of = 18 keV for the compound nucleus 34 Cl at 17,2 MeV excitation

Fluence-to-Absorbed Dose Conversion Coefficients for Use in Radiological Protection of Embryo and Foetus Against External Exposure to Muons from 20MeV to 50GeV

International Nuclear Information System (INIS)

Chen Jing

2008-01-01

This study used the Monte-Carlo code MCNPX to determine mean absorbed doses to the embryo and foetus when the mother is exposed to external muon fields. Monoenergetic muons ranging from 20 MeV to 50 GeV were considered. The irradiation geometries include anteroposterior (AP), postero-anterior (PA), lateral (LAT), rotational (ROT), isotropic (ISO), and top-down (TOP). At each of these irradiation geometries, absorbed doses to the foetal body were calculated for the embryo of 8 weeks and the foetus of 3, 6 or 9 months, respectively. Muon fluence-to-absorbed-dose conversion coefficients were derived for the four prenatal ages. Since such conversion coefficients are yet unknown, the results presented here fill a data gap

A compact sup 3 H(p,gamma) sup 4 He 19.8 MeV gamma-ray source for energy calibration at the Sudbury Neutrino Observatory

CERN Document Server

Poon, A W P; Waltham, C E; Browne, M C; Robertson, R G H; Kherani, N P; Mak, H B

2000-01-01

The Sudbury Neutrino Observatory (SNO) is a new 1000-t D sub 2 O Cherenkov solar neutrino detector. A high-energy gamma-ray source is needed to calibrate SNO beyond the sup 8 B solar neutrino endpoint of 15 MeV. This paper describes the design and construction of a source that generates 19.8 MeV gamma rays using the sup 3 H(p,gamma) sup 4 He reaction (''pT''), and demonstrates that the source meets all the physical, operational and lifetime requirements for calibrating SNO. An ion source was built into this unit to generate and to accelerate protons up to 30 keV, and a high-purity scandium tritide target with a scandium-tritium atomic ratio of 1 : 2.0+-0.2 was included. This pT source is the first self-contained, compact, and portable high-energy gamma-ray source (E subgamma>10 MeV). (authors)

Shielding calculations for a 30 MeV proton accelerator

International Nuclear Information System (INIS)

Nandy, Maitreyee; Sarkar, P.K.

2003-01-01

Full text: The thickness of the shield, made of ordinary concrete, required to reduce the equivalent dose rate below the maximum permissible limit and to ensure safe operation of a 30 MeV proton accelerator has been estimated using the Moyer model. Required double differential neutron yield from thick stopping targets has been calculated for several reactions to be used for production of 67 Ga, 111 In, 123 I and 201 Tl radioisotopes. The neutron emission at 0 deg and 90 deg angles with respect to the incident beam direction is estimated using the hybrid model code ALICE91 which considers preequilibrium and equilibrium emissions from the target+projectile composite system. From this neutron yield the equivalent neutron dose rate at unit distance is determined using the ICRP recommended flux-to-dose conversion factors

Phenomenology of a very light scalar (100 MeV GeV) mixing with the SM Higgs

Energy Technology Data Exchange (ETDEWEB)

Clarke, Jackson D.; Foot, Robert; Volkas, Raymond R. [ARC Centre of Excellence for Particle Physics at the Terascale, School of Physics, University of Melbourne, VIC 3010 (Australia)

2014-02-27

In this paper we investigate the phenomenology of a very light scalar, h, with mass 100 MeV GeV, mixing with the SM Higgs. As a benchmark model we take the real singlet scalar extension of the SM. We point out apparently unresolved uncertainties in the branching ratios and lifetime of h in a crucial region of parameter space for LHC phenomenology. Bounds from LEP, meson decays and fixed target experiments are reviewed. We also examine prospects at the LHC. For m{sub h}≲m{sub B} the dominant production mechanism is via meson decay; our main result is the calculation of the differential p{sub T} spectrum of h scalars originating from B mesons and the subsequent prediction of up to thousands of moderate (triggerable) p{sub T} displaced dimuons possibly hiding in the existing dataset at ATLAS/CMS or at LHCb. We also demonstrate that the subdominant Vh production channel has the best sensitivity for m{sub h}≳m{sub B} and that future bounds in this region could conceivably compete with those of LEP.

Fission and fragmentation of silver and bromine nuclei by 1-6 GeV energy photons

International Nuclear Information System (INIS)

Pinheiro Filho, J. de D.

1983-01-01

Fission and fragmentation of silver and bromine nuclei induced by bremsstrahlung photons in the maximum energy range of 1-6 GeV are studied. A special technique of nuclear emulsion for the highly ionizing nuclear fragment detection is used in the discrimination between nuclear fission and fragmentation events. Films of Ilford-KO nuclear emulsion (approximatelly 10 20 atoms/cm 2 of Ag, Br) which had been exposed to bremsstrahlung beams in 'Deutsches Elektronen Synchrotron' (DESY, Hamburg) with total doses of approximatelly 10 11 equivalent photons are used. Through a detailed analysis of range, angular and angle between fragment distributions, and empirical relations which permit to estimate nuclear fragment energy, range and velocity, the discrimination between fission and fragmentation events is made. Results related to fragment range distribution, angular distribution, distribution of angle between fragments, distribution of ratio between ranges, velocity distributions, forward/backward ratio, fission and fragmentation cross sections, nuclear fissionability and ternary fission frequency are presented and discussed. The results show that the mean photofragmentation cross section in the internal 1-6 GeV (0,09+-0,02mb) is significant when compared to the photofission (0,29+-0,05mb). It is also shown that the mean photofission cross section between 1 and 6 GeV is great by a factor of approximatelly 10 when compared to the foreseen by the cascade-evaporation nuclear model for monoenergetic photons of 0,6 GeV. (L.C.) [pt

Proposal on the measurements of d-p elastic scattering analyzing powers at 0.3-2.0 GeV at internal target station of the Nuclotron

International Nuclear Information System (INIS)

Uesaka, T.; Ladygin, V.P.; Azhgirej, L.S.

2005-01-01

A new high-energy beam polarimeter is proposed for the Nuclotron using Internal Target Station. This polarimeter based on the measurement of the asymmetry for the d-p elastic scattering will allow one to measure both vector and tensor components of the deuteron beam polarization simultaneously. For that purpose the measurement of analyzing powers for the d-p elastic scattering at energies T d = 0.88-2 GeV is proposed. The precise measurements of the deuteron analyzing powers over energy range T d 300-2000 MeV can give an irreplaceable clue on the study of spin-dependence of three-nucleon forces

Differential cross sections of proton Compton scattering at photon laboratory energies between 1.2 and 1.7 GeV

International Nuclear Information System (INIS)

Duda, J.; Hoefner, F.W.; Jung, M.; Kleissler, R.; Kueck, H.; Leu, P.; Marne, K.D. de; Munk, B.; Vogl, W.; Wedemeyer, R.

1982-11-01

Differential cross sections of proton Compton scattering have been measured at the Bonn 2.5 GeV synchrotron. The experiment covers photon laboratory energies between 1.2 GeV and 1.7 GeV and the square of the four-momentum transfer ranges from t = -0.17 GeV 2 to -0.98 GeV 2 corresponding to c.m. scattering angles between 35 0 and 80 0 . The cross sections exhibit a forward peak followed by a monotone fall-off up to the largest measured vertical stroketvertical stroke-values. Fits of the form dsigma/dt = A.exp(Bt) to the data points with vertical stroketvertical stroke 2 yield forward cross sections A, which are consistent with the 0 0 cross sections calculated from the measured total photon-proton cross section. The average slope is B = 5.6 +- 0.14 GeV 2 . (orig.)

Measurements of Neutron Spectra Produced from a Thick Iron Target Bombarded with 1.5-GeV Protons

International Nuclear Information System (INIS)

Meigo, Shin-ichiro; Shigyo, Nobuhiro; Iga, Kiminori; Iwamoto, Yosuke; Kitsuki, Hirohiko; Ishibashi, Kenji; Maehata, Keisuke; Arima, Hidehiko; Nakamoto, Tatsushi; Numajiri, Masaharu

2005-01-01

For validation of calculation codes that are employed in the design of accelerator facilities, spectra of neutrons produced from a thick iron target bombarded with 1.5-GeV protons were measured. The calculated results with NMTC/JAM were compared with the present experimental results. It is found that the NMTC/JAM generally shows good agreement with experiment. Furthermore, the calculation gives good agreement with the experiment for the energy region 20 to 80 MeV for iron, whereas the NMTC/JAM gives 50% of the experimental data for the heavy-nuclides such as lead and tungsten

Measurements of neutron spectra produced from a thick iron target bombarded with 1.5 GeV protons

International Nuclear Information System (INIS)

Meigo, Shin-ichiro; Takada, Hiroshi

2001-01-01

For validation of calculation codes which are employed in the design of accelerator facilities, spectra of neutrons produced from a thick iron target bombarded with 1.5-GeV protons were measured. The calculated results with NMTC/JAM were compared with the present experimental results. It is found the NMTC/JAM generally shows in good agreement with experiment. Furthermore, the calculation gives good agreement with the experiment for the energy region 20-80 MeV, whereas the NMTC/JAM gives 50% of the experimental data for the heavy nuclide target such as lead and tungsten target. (author)

ADS-HE: Evaluated Nuclear Data Library up to 1 GeV for 202Hg, 208Pb, 209Bi, 232Th, 235U, 238U, 237Np, 239Pu, 242Am and 245Cm

International Nuclear Information System (INIS)

Lopez Aldama, Daniel

2013-12-01

Accelerator Driven Systems (ADS) are being developed for power generation and the transmutation of actinide and fission product waste, and well-defined cross-section libraries suitable for their transport calculations are required. Transport of high energy neutrons and protons near the target assembly requires an extension of the library for incident energies up to 1 GeV. An ADS-HE library for incident neutrons on selected target elements has been developed to meet this request, and assist benchmarking studies linked to ADS experiments and design concepts. New evaluations of high-energy data from 20 MeV up to 1 GeV have been carried out by S.G. Yavshits and O.T. Grudzevich (see INDC(NDS)-0615). The ADS- HE library has been prepared from these high-energy evaluations combined with evaluations below 20 MeV selected from the ENDF/B-VII.1, the JEFF-3.1.2 and the JENDL-4u2 libraries. The ADS-HE library was processed in suitable forms for Monte Carlo transport codes used in the analysis of ADS. ADS-HE is freely available from the IAEA Nuclear Data Section, and is readily accessible on the web site: http://www-nds.iaea.org/ads/adshe.html. (author)

The Effect of Proton Energy on SEU Cross-Section of a 16Mbit TFT PMOS SRAM with DRAM Capacitors

CERN Document Server

Uznanski, Slawosz; Blackmore, Ewart; Brugger, Markus; Gaillard, Remi; Mekki, Julien; Todd, Benjamin; Trinczek, Michael; Vilar Villanueva, Andrea

2014-01-01

Proton experimental data are analyzed for a 16-Mbit Thin-Film-Transistor (TFT) PMOS Static Random Access Memory (SRAM) with DRAM capacitors. The presence of high-Z materials as tungsten causes an unusual increase of the Single Event Upset (SEU) proton cross-section for the energies above 100MeV. Monte-Carlo simulations reproduce the experimentally measured cross-sections up to 480MeV and predict a further increase up to GeV energies. The implications of this increase are analyzed in the context of the LHC and other radiation environments where a significant fraction of the fluence lies above 100MeV.

Studies on a modular high-energy photon spectrometer of pure CsI scintillators

International Nuclear Information System (INIS)

Kopyto, D.

1994-04-01

Aim of the present thesis is the optimization of components for the construction of a high-energy photon spectrometer of pure CsI for the detection of the neutral pseudoscalar mesons π 0 , η, and η' at COSY. These mesons are distinguished by their decay into two γ quanta and can therefore be detected by means of a photon spectrometer. A concept of a 2-arm shower counter of pure CsI is presented. Conclusions on the energy resolution of such a calorimeter shall yield a test module, which is constructed of 5.5 CsI(pure) pyramide trunk, each of which possesses a length of 30 cm and an angular acceptance of 6 .6 . The geometry of the moduls is formed in such a way that its extension to a 2-arm shower counter is possible at any time. Hitherto 14 by teflon foils wrapped up crystals for the test module were tested. Their energy resolution varies at 0.66 MeV between 20 and 25 % FWHM. Furthermore a method was found, which allows to trim the position dependence to the required values. So for the position dependence of a crystal even a value of 1.1 % could be reached. The energy resolution amounted thereby to 22 % FWHM. A measurement of the energy resolution with 20 MeV protons yielded a value of 7 %. For the energy calibration of the single detector elements in a dynamic range between 1 MeV and 12 GeV with low-energy γ sources the charge response function of the photoelectron multiplier to be applied in the test module was determined in dependence on the light intensity. The measurement resulted that the photomultiplier at 40 MeV (related to a CsI(pure) reference crystal with an about twofold so high efficiency of the detectable light in comparison to the long pyramide trunks) deviates by 4 % and at 300 MeV by 38 % from the linear behaviour, while it at 500 MeV shows a deviation of 50 %

Heating nuclei with light ions at GeV incident energies

International Nuclear Information System (INIS)

Pollacco, E.C.; Brzychczyk, J.; Volant, C.; Legrain, R.; Nalpas, L.; Bracken, D.S.; Kwiatkowski, K.; Morley, K.B.; Foxford, E.R.; Viola, V.E.; Yoder, N.R.

1996-03-01

Hot nuclei are studied, where through an appropriate choice of incident channel and event selection, dynamical effects are attenuated and multifragmentation is limited. Three preparatory results are discussed, the 3 He(1.8 GeV) + nat Ag can be described using and intranuclear cascade, INC, model; through a suitable selection of events a limit of the excitation energy that a nucleus can absorb without breaking into large pieces is given, it is shown, that corresponding alpha decay is consistent with an, evaporative process. (K.A.)

The eight modes observation in LiNbO3 induced by 3.0 MeV He+ implantation

International Nuclear Information System (INIS)

Wang Keming; Shi Borong; Zhou Zhuang; Wang Wei; Ding Peijun; Wang Zhonglie.

1994-01-01

The y-cut LiNbO 3 was implanted by 3.0 MeV He + to a dose of 2 x10 16 ions/cm 2 at liquid nitrogen temperature. The eight black and bright modes from He implanted LiNbO 3 waveguide were observed before and after rapid annealing. The refractive index profile is obtained by means of a non-stationary mode index calculation. The comparison of refractive index profile with damage profile is given. The result shows that the peak position of the refractive index profile is found to be in good agreement with the peak position of damage profile induced by 3.0 MeV He + implanted in LiNbO 3 based on transport of ions in matter (TRIM'92).(author)

Measurements of fission product yield in the neutron-induced fission of 238U with average energies of 9.35 MeV and 12.52 MeV

Science.gov (United States)

Mukerji, Sadhana; Krishnani, Pritam Das; Shivashankar, Byrapura Siddaramaiah; Mulik, Vikas Kaluram; Suryanarayana, Saraswatula Venkat; Naik, Haladhara; Goswami, Ashok

2014-07-01

The yields of various fission products in the neutron-induced fission of 238U with the flux-weightedaveraged neutron energies of 9.35 MeV and 12.52 MeV were determined by using an off-line gammaray spectroscopic technique. The neutrons were generated using the 7Li(p, n) reaction at Bhabha Atomic Research Centre-Tata Institute of Fundamental Research Pelletron facility, Mumbai. The gamma- ray activities of the fission products were counted in a highly-shielded HPGe detector over a period of several weeks to identify the decaying fission products. At both the neutron energies, the fission-yield values are reported for twelve fission product. The results obtained from the present work have been compared with the similar data for mono-energetic neutrons of comparable energy from the literature and are found to be in good agreement. The peak-to-valley (P/V) ratios were calculated from the fission-yield data and were found to decreases for neutron energy from 9.35 to 12.52 MeV, which indicates the role of excitation energy. The effect of the nuclear structure on the fission product-yield is discussed.

Combination of the H1 and ZEUS inclusive cross-section measurements at proton beam energies of 460 GeV and 575 GeV and tests of low Bjorken-x phenomenological models

International Nuclear Information System (INIS)

Belov, Pavel

2013-06-01

A combination is presented of the inclusive neutral current e ± p scattering cross section data collected by the H1 and ZEUS collaborations during the last months of the HERA II operation period with proton beam energies E p of 460 and 575 GeV. The kinematic range of the cross section data covers low absolute four-momentum transfers squared, 1.5 GeV 2 ≤ Q 2 ≤ 110 GeV 2 , small values of Bjorken-x, 2.8.10 -5 ≤ x ≤ 1.5.10 -2 , and high inelasticity y ≤ 0.85. The combination algorithm is based on the method of least squares and takes into account correlations of the systematic uncertainties. The combined data are used in the QCD fits to extract the parton distribution functions. The phenomenological low-x dipole models are tested and parameters of the models are obtained. A good description of the data by the dipole model taking into account the evolution of the gluon distribution is observed. The longitudinal structure function F L is extracted from the combination of the currently used H1 and ZEUS reduced proton beam energy data with previously published H1 nominal proton beam energy data of 920 GeV. A precision of the obtained values of F L is improved at medium Q 2 compared to the published results of the H1 collaboration.

pi0 photoproduction on the proton for photon energies from 0.675 to 2.875-GeV

Energy Technology Data Exchange (ETDEWEB)

Michael Dugger; Barry Ritchie; Jacques Ball; Patrick Collins; Evgueni Pasyuk; Richard Arndt; William Briscoe; Igor Strakovski; Ron Workman; Gary Adams; Moscov Amaryan; Pawel Ambrozewicz; Eric Anciant; Marco Anghinolfi; Burin Asavapibhop; G. Asryan; Gerard Audit; Harutyun Avakian; H. Bagdasaryan; Nathan Baillie; Nathan Baltzell; Steve Barrow; Marco Battaglieri; Kevin Beard; Ivan Bedlinski; Ivan Bedlinskiy; Mehmet Bektasoglu; Matthew Bellis; Nawal Benmouna; Barry Berman; Nicola Bianchi; Angela Biselli; Billy Bonner; Sylvain Bouchigny; Sergey Boyarinov; Robert Bradford; Derek Branford; William Brooks; Stephen Bueltmann; Volker Burkert; Cornel Butuceanu; John Calarco; Sharon Careccia; Daniel Carman; Bryan Carnahan; Shifeng Chen; Philip Cole; Alan Coleman; Philip Coltharp; Dieter Cords; Pietro Corvisiero; Donald Crabb; Hall Crannell; John Cummings; Enzo De Sanctis; Raffaella De Vita; Pavel Degtiarenko; Haluk Denizli; Lawrence Dennis; Alexandre Deur; Kahanawita Dharmawardane; Kalvir Dhuga; Richard Dickson; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; P. Dragovitsch; Steven Dytman; Oleksandr Dzyubak; Hovanes Egiyan; Kim Egiyan; Latifa Elouadrhiri; A. Empl; Paul Eugenio; Renee Fatemi; Gleb Fedotov; Gerald Feldman; Robert Feuerbach; John Ficenec; Tony Forest; Herbert Funsten; Michel Garcon; Gagik Gavalian; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; John Goetz; Ralf Gothe; Keith Griffioen; Michel Guidal; Matthieu Guillo; Nevzat Guler; Lei Guo; Vardan Gyurjyan; Cynthia Hadjidakis; Rafael Hakobyan; John Hardie; D. Heddle; F. Hersman; Kenneth Hicks; Ishaq Hleiqawi; Maurik Holtrop; J. Hu; Marco Huertas; Charles Hyde; Charles Hyde-Wright; Yordanka Ilieva; David Ireland; Boris Ishkhanov; Mark Ito; David Jenkins; Hyon-Suk Jo; Kyungseon Joo; Henry Juengst; Narbe Kalantarians; James Kellie; Mahbubul Khandaker; Kui Kim; Kinney Kim; Wooyoung Kim; Andreas Klein; Franz Klein; Alexei Klimenko; Mike Klusman; Mikhail Kossov; Zebulun Krahn; Laird Kramer; Valery Kubarovsky; Joachim Kuhn; Sebastian Kuhn; Viacheslav Kuznetsov; Jeff Lachniet; Jean Laget; Jorn Langheinrich; David Lawrence; Tsung-shung Lee; Ana Lima; Kenneth Livingston; K. Lukashin; Joseph Manak; Claude Marchand; Leonard Maximon; Simeon McAleer; Bryan McKinnon; John McNabb; Bernhard Mecking; Mac Mestayer; Curtis Meyer; Tsutomu Mibe; Konstantin Mikhaylov; Ralph Minehart; Marco Mirazita; Rory Miskimen; Viktor Mokeev; Kei Moriya; Steven Morrow; Valeria Muccifora; James Mueller; Gordon Mutchler; Pawel Nadel-Turonski; James Napolitano; Rakhsha Nasseripour; Silvia Niccolai; Gabriel Niculescu; Maria-Ioana Niculescu; Bogdan Niczyporuk; Megh Niroula; Rustam Niyazov; Mina Nozar; Grant O' Rielly; Mikhail Osipenko; Alexander Ostrovidov; K Park; Craig Paterson; Sasha Philips; Joshua Pierce; Nikolay Pivnyuk; Dinko Pocanic; Oleg Pogorelko; S. Pozdniakov; Barry Preedom; John Price; Yelena Prok; Dan Protopopescu; Liming Qin; Brian Raue; Gregory Riccardi; Giovanni Ricco; Marco Ripani; Federico Ronchetti; Guenther Rosner; Patrizia Rossi; David Rowntree; Philip Rubin; Franck Sabatie; Julian Salamanca; Carlos Salgado; Joseph Santoro; Vladimir Sapunenko; Reinhard Schumacher; Vladimir Serov; Aziz Shafi; Youri Sharabian; J. Shaw; Sebastio Simionatto; Alexander Skabelin; Elton Smith; Lee Smith; Daniel Sober; M. Spraker; Aleksey Stavinskiy; Samuel Stepanyan; Stepan Stepanyan; Burnham Stokes; Paul Stoler; Steffen Strauch; Mauro Taiuti; Simon Taylor; David Tedeschi; Ulrike Thoma; R. Thompson; Avtandil Tkabladze; Svyatoslav Tkachenko; Luminita Todor; Clarisse Tur; Maurizio Ungaro; Michael Vineyard; Alexander Vlassov; Xue kai Wang; Lawrence Weinstein; Henry Weller; Dennis Weygand; M. Williams; Elliott Wolin; M.H. Wood; A. Yegneswaran; Jae-Chul Yun; Lorenzo Zana; Jixie Zhang

2007-07-23

Differential cross sections for the reaction $\\gamma p \\to p \\pi^0$ have been measured with the CEBAF Large Acceptance Spectrometer (CLAS) and a tagged photon beam with energies from 0.675 to 2.875 GeV. The results reported here possess greater accuracy in the absolute normalization than previous measurements. They disagree with recent CB-ELSA measurements for the process at forward scattering angles. Agreement with the SAID and MAID fits is found below 1 GeV. The present set of cross sections has been incorporated into the SAID database, and exploratory fits have been extended to 3 GeV. Resonance couplings have been extracted and compared to previous determinations.

Helions at energies of 10 MeV to 1 TeV: Conversion coefficients for fluence-to-absorbed dose, equivalent dose, effective dose and gray equivalent, calculated using Monte Carlo radiation transport code MCNPX 2.7.C

International Nuclear Information System (INIS)

Copeland, K.; Parker, D. E.; Friedberg, W.

2010-01-01

Conversion coefficients were calculated for fluence-to-absorbed dose, fluence-to-equivalent dose, fluence-to-effective dose and fluence-to-gray equivalent, for isotropic exposure of an adult male and an adult female to helions ( 3 He 2+ ) in the energy range of 10 MeV to 1 TeV (0.01-1000 GeV). Calculations were performed using Monte Carlo transport code MCNPX 2.7.C and BodyBuilder TM 1.3 anthropomorphic phantoms modified to allow calculation of effective dose using tissues and tissue weighting factors from either the 1990 or 2007 recommendations of the International Commission on Radiological Protection (ICRP), and gray equivalent to selected tissues as recommended by the National Council on Radiation Protection and Measurements. At 15 of the 19 energies for which coefficients for effective dose were calculated, coefficients based on ICRP 2007 and 1990 recommendations differed by less than 2%. The greatest difference, 62%, occurred at 100 MeV. Published by Oxford Univ. Press on behalf of the U.S. Government 2010. (authors)

Total photoabsorption cross section on nuclei measured in energy range 0.5-2.6 GeV

International Nuclear Information System (INIS)

Mirazita, M.

1998-03-01

The total photoabsorption cross section on several nuclei has been measured in the energy range 0.5 - 2.6 GeV. Nuclear data show a significant reduction of the absorption strength with respect to the free nucleon case suggesting a shadowing effect at low energies

Search for supersymmetry with a dominant R-parity violating $LL\\overline{E}$ coupling in $e^+ e^-$ collisions at centre-of-mass energies of 130 GeV to 172 GeV

CERN Document Server

Barate, R.; Decamp, D.; Ghez, Philippe; Goy, C.; Lees, J.P.; Lucotte, A.; Minard, M.N.; Nief, J.Y.; Pietrzyk, B.; Boix, G.; Casado, M.P.; Chmeissani, M.; Crespo, J.M.; Delfino, M.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, L.; Grauges, E.; Juste, A.; Martinez, M.; Merino, G.; Miguel, R.; Mir, L.M.; Morawitz, P.; Park, I.C.; Pascual, A.; Perlas, J.A.; Riu, I.; Sanchez, F.; Colaleo, A.; Creanza, D.; De Palma, M.; Gelao, G.; Iaselli, G.; Maggi, G.; Maggi, M.; Marinelli, N.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Alemany, R.; Becker, U.; Bright-Thomas, P.; Casper, D.; Cattaneo, M.; Cerutti, F.; Ciulli, V.; Dissertori, G.; Drevermann, H.; Forty, R.W.; Frank, M.; Gianotti, F.; Hagelberg, R.; Hansen, J.B.; Harvey, John; Janot, P.; Jost, B.; Leahraus, I.; Mato, P.; Minten, A.; Moneta, L.; Pacheco, A.; Pusztaszeri, J.F.; Ranjard, F.; Rolandi, Gigi; Rousseau, D.; Schlatter, D.; Schmitt, M.; Schneider, O.; Tejessy, W.; Teubert, F.; Tomalin, I.R.; Vreeswijk, M.; Wachsmuth, H.; Wagner, A.; Ajaltouni, Z.; Badaud, F.; Chazelle, G.; Deschamps, O.; Falvard, A.; Ferdi, C.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Rosnet, P.; Fearnley, T.; Hansen, J.D.; Hansen, J.R.; Hansen, P.H.; Nilsson, B.S.; Rensch, B.; Waananen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Vayaki, A.; Blondel, A.; Brient, J.C.; Machefert, F.; Rouge, A.; Rumpf, M.; Valassi, A.; Videau, H.; Boccali, T.; Focardi, E.; Parrini, G.; Zachariadou, K.; Cavanaugh, R.; Corden, M.; Georgiopoulos, C.; Huehn, T.; Jaffe, D.E.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G.P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Dorris, S.J.; Halley, A.W.; Lynch, J.G.; Negus, P.; O'Shea, V.; Raine, C.; Scarr, J.M.; Smith, K.; Teixeira-Dias, P.; Thompson, A.S.; Thomson, Evelyn J.; Thomson, F.; Buchmuller, O.; Dhamotharan, S.; Geweniger, C.; Graefe, G.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E.E.; Putzer, A.; Sommer, J.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D.M.; Cameron, W.; Dornan, P.J.; Girone, M.; Goodsir, S.; Martin, E.B.; Moutoussi, A.; Nash, J.; Sedgbeer, J.K.; Spagnolo, P.; Williams, M.D.; Ghete, V.M.; Girtler, P.; Kneringer, E.; Kuhn, D.; Rudolph, G.; Betteridge, A.P.; Bowdery, C.K.; Buek, P.G.; Colrain, P.; Crawford, G.; Finch, A.J.; Foster, F.; Hughes, G.; Jones, R.W.L.; Whelan, E.P.; Williams, M.I.; Giehl, I.; Hoffmann, C.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.G.; van Gemmeren, P.; Zeitnitz, C.; Aubert, J.J.; Benchouk, C.; Bonissent, A.; Bujosa, G.; Carr, J.; Coyle, P.; Diaconu, C.; Ealet, A.; Fouchez, D.; Leroy, O.; Payre, P.; Talby, M.; Sadouki, A.; Thulasidas, M.; Tilquin, A.; Trabelsi, K.; Aleppo, M.; Antonelli, M.; Ragusa, F.; Berlich, R.; Blum, W.; Buescher, Volker; Dietl, H.; Ganis, G.; Gotzhein, C.; Kroha, H.; Lutjens, G.; Lutz, G.; Mannert, C.; Manner, W.; Moser, H.G.; Richter, Robert, 1; Rosado-Schlosser, A.; Schael, S.; Settles, R.; Seywerd, H.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Boucrot, J.; Callot, O.; Chen, S.; Davier, M.; Duflot, L.; Grivaz, J.F.; Heusse, P.; Hocker, Andreas; Jacholkowska, A.; Kado, M.M.; Kim, D.W.; Le Diberder, F.; Lefrancois, J.; Lutz, A.M.; Schune, M.H.; Serin, L.; Tournefier, E.; Veillet, J.J.; Videau, I.; Zerwas, D.; Azzurri, P.; Bagliesi, Giuseppe; Bettarini, S.; Bozzi, C.; Calderini, G.; Dell'Orso, R.; Fantechi, R.; Ferrante, I.; Giassi, A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P.S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Sciaba, A.; Sguazzoni, G.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Vannini, C.; Venturi, A.; Verdini, P.G.; Blair, G.A.; Bryant, L.M.; Chambers, J.T.; Coles, J.; Green, M.G.; Medcalf, T.; Perrodo, P.; Strong, J.A.; von Wimmersperg-Toeller, J.H.; Botterill, D.R.; Clifft, R.W.; Edgecock, T.R.; Haywood, S.; Maley, P.; Norton, P.R.; Thompson, J.C.; Wright, A.E.; Bloch-Devaux, Brigitte; Colas, P.; Fabbro, B.; Faif, G.; Lancon, E.; Lemaire, M.C.; Locci, E.; Perez, P.; Przysiezniak, H.; Rander, J.; Renardy, J.F.; Rosowsky, A.; Roussarie, A.; Trabelsi, A.; Vallage, B.; Black, S.N.; Dann, J.H.; Kim, H.Y.; Konstantinidis, N.; Litke, A.M.; McNeil, M.A.; Taylor, G.; Booth, C.N.; Brew, C.A.J.; Cartwright, S.; Combley, F.; Kelly, M.S.; Lehto, M.; Reeve, J.; Thompson, L.F.; Affholderbach, K.; Boehrer, Armin; Brandt, S.; Cowan, G.; Foss, J.; Grupen, C.; Smolik, L.; Stephan, F.; Apollonio, M.; Bosisio, L.; Della Marina, R.; Giannini, G.; Gobbo, B.; Musolino, G.; Putz, J.; Rothberg, J.; Wasserbaech, S.; Williams, R.W.; Armstrong, S.R.; Charles, E.; Elmer, P.; Ferguson, D.P.S.; Gao, Y.S.; Gonzalez, S.; Greening, T.C.; Hayes, O.J.; Hu, H.; Jin, S.; McNamara, P.A., III; Nachtman, J.M.; Nielsen, J.; Orejudos, W.; Pan, Y.B.; Saadi, Y.; Scott, I.J.; Walsh, J.; Wu, Sau Lan; Wu, X.; Yamartino, J.M.; Zobernig, G.

1998-01-01

A search for pair-production of supersymmetric particles under the assumption that R-parity is violated via a dominant LLE coupling has been performed using the data collected by ALEPH at centre-of-mass energies of 130-172 GeV. The observed candidate events in the data are in agreement with the Standard Model expectation. This is translated into lower limits on the mass of charginos, neutralinos, sleptons, sneutrinos and squarks. For instance, charginos with masses less than 73 GeV and neutralinos with masses less than 23 GeV are excluded at 95% confidence level for any generation structure of the LLE coupling, and for neutralino, slepton or sneutrino LSPs.

Development of dose monitoring system applicable to various radiations with wide energy ranges

International Nuclear Information System (INIS)

Sato, Tatsuhiko; Satoh, Daiki; Endo, Akira

2006-01-01

A new radiation dose monitor, designated as DARWIN (Dose monitoring system Applicable to various Radiations with WIde energy raNges), has been developed for real-time monitoring of doses in workspaces and surrounding environments of high energy accelerator facilities. DARWIN is composed of a phoswitch-type scintillation detector, which consists of liquid organic scintillator BC501A coupled with ZnS(Ag) scintillation sheets doped with 6 Li, and a data acquisition system based on a Digital-Storage-Oscilloscope. DARWIN has the following features: (1) capable of monitoring doses from neutrons, photons and muons with energies from thermal energy to 1 GeV, 150 keV to 100 MeV, and 1 MeV to 100 GeV, respectively, (2) highly sensitive with precision, and (3) easy to operate with a simple graphical user-interface. The performance of DARWIN was examined experimentally in several radiation fields. The results of the experiments indicated the accuracy and rapid response of DARWIN for measuring dose rates from neutrons, photons and muons with wide energies. With these properties, we conclude that DARWIN will be able to play a very important role for improving radiation safety in high energy accelerator facilities. (author)

Measurement of the e+e−→π+π− cross section between 600 and 900 MeV using initial state radiation

Directory of Open Access Journals (Sweden)

M. Ablikim

2016-02-01

Full Text Available We extract the e+e−→π+π− cross section in the energy range between 600 and 900 MeV, exploiting the method of initial state radiation. A data set with an integrated luminosity of 2.93 fb−1 taken at a center-of-mass energy of 3.773 GeV with the BESIII detector at the BEPCII collider is used. The cross section is measured with a systematic uncertainty of 0.9%. We extract the pion form factor |Fπ|2 as well as the contribution of the measured cross section to the leading-order hadronic vacuum polarization contribution to (g−2μ. We find this value to be aμππ,LO(600–900MeV=(368.2±2.5stat±3.3sys⋅10−10, which is between the corresponding values using the BaBar or KLOE data.

Optical model analysis for 30MeV polarized proton elastic scattering

International Nuclear Information System (INIS)

Pham, D.-L.; Swiniarski, R. de.

1977-05-01

The proton elastic scattering cross sections and analyzing powers at 30MeV have been used to derive optical model parameters for ten elements from 10 B to 32 S. A set of average geometrical parameters (rsub(o)=1.10fm, rsub(LS)=1.0fm and asub(I)=0.60fm) is found to give good fits to the entire data, the other geometrical parameters being rsub(I)=(1.35+-0.15)fm, asub(o)=(0.75+-0.10)fm and asub(LS)=(0.35+-0.07)fm. The dynamical parameters with fixed geometry are presented

Measurement of the 209Bi(n ,4 n )206Bi and 169Tm(n ,3 n )167Tm cross sections between 23.5 and 30.5 MeV relevant to reaction-in-flight neutron studies at the National Ignition Facility

Science.gov (United States)

Gooden, M. E.; Bredeweg, T. A.; Champine, B.; Combs, D. C.; Finch, S.; Hayes-Sterbenz, A.; Henry, E.; Krishichayan, Rundberg, R.; Tornow, W.; Wilhelmy, J.; Yeamans, C.

2017-08-01

At the National Ignition Facility, experiments are being performed to measure charged-particle stopping powers in the previously unexplored warm dense plasma regime. These measurements are done using reaction-in-flight (RIF) neutrons from an inertial confinement fusion system. RIF neutrons are produced with a continuum of energies up to 30 MeV. By making activation measurements utilizing threshold reactions for neutrons in the energy range of 15 30 MeV , the number of RIF neutrons can be determined and from this the stopping power of the deuterium and tritium ions that produced the RIF neutrons can be inferred. Currently, the 169Tm(n ,3 n )167Tm reaction has been used. However, in an effort to provide a secondary complimentary measurement, efforts are underway to make use of the 209Bi(n ,4 n )206Bi reaction, with a threshold of 22.5 MeV. The cross sections were measured at the 10 MV tandem Van De Graaff accelerator at the Triangle Universities Nuclear Laboratory with quasimonoenergetic neutrons between 23.5 and 30.5 MeV, where few previous measurements have been made. Cross-section data are compared to calculations and other available measurements.

Asymmetry of the cross section for the reaction. gamma. d. -->. pi. /sup 0/d with linearly polarized. gamma. rays at 500--700 MeV and at a c. m. angle theta(0 = 130/sup 0/

Energy Technology Data Exchange (ETDEWEB)

Adamyan, F.V.; Akopyan, G.G.; Vartapetyan, G.A.; Galumyan, P.I.; Grabskii, V.O.; Karapetyan, V.V.; Karapetyan, G.V.; Oktanyan, V.K.

1984-06-25

The asymmetry of the cross section (..sigma..) of the reaction ..gamma..d ..-->.. ..pi../sup 0/d induced by linearly polarized ..gamma.. rays has been measured at energies E..gamma.. = 500 MeV, E..gamma.. = 600, and E/sub ..gamma../ = 700 MeV at the c.m. angle theta(0 = 130/sup 0/. The results disagree with calculations in the impulse approximation. The results can be explained in a qualitative way by appealing to an /sup 3/F/sub 3/ (2.26-GeV) dibaryon resonance.

Range-energy relations and stopping power of water, water vapour and tissue equivalent liquid for α particles over the energy range 0.5 to 8 MeV

International Nuclear Information System (INIS)

Palmer, R.B.J.; Akhavan-Rezayat, Ahmad

1978-01-01

Experimental range-energy relations are presented for alpha particles in water, water vapour and tissue equivalent liquid at energies up to 8 MeV. From these relations differential stopping powers are derived at 0.25 MeV energy intervals. Consideration is given to sources of error in the range-energy measurements and to the uncertainties that these will introduce into the stopping power values. The ratio of the differential stopping power of muscle equivalent liquid to that of water over the energy range 0.5 to 7.5 MeV is discussed in relation to the specific gravity and chemical composition of the muscle equivalent liquid. Theoretical molecular stopping power calculations based upon the Bethe formula are also presented for water. The effect of phase upon the stopping power of water is discussed. The molecular stopping power of water vapour is shown to be significantly higher than that of water for energies below 1.25 MeV and above 2.5 MeV, the ratio of the two stopping powers rising to 1.39 at 0.5 MeV and to 1.13 at 7.0 MeV. Stopping power measurements for other liquids and vapours are compared with the results for water and water vapour and some are observed to have stopping power ratios in the vapour and liquid phases which vary with energy in a similar way to water. It is suggested that there may be several factors contributing to the increased stopping power of liquids. The need for further experimental results on a wider range of liquids is stressed

Experimental and theoretical study of directional effects on radiation and pair creation in crystal at energies near 100 GeV

International Nuclear Information System (INIS)

Belkacem, A.

1986-07-01

We investigated the electron-positron pair production from incident photons on a thin crystal. When the photon energy is higher than about 30 GeV, the pair production rate from a photon beam aligned along a crystal direction is higher than the rate measured with an amorphous target (Bethe-Heitler value). In contrast with what was observed for a random orientation (or with an amorphous target) the pair production rate increases sharply with the photon energy. We also investigated the radiation emitted by high energy electrons and positrons (70-200 GeV) along a crystal direction. The intensity of the radiation was found to be extremely high. The increase of the intensity of these two electromagnetic processes (radiation and pair creation) was still observed for incident angles much larger than the channeling critical angle. Thus, a theory based on the channeling phenomenon is not able to explain such observations. In order to understand these new phenomena we developed a new theoretical approach based on the electromagnetic interaction in strong fields. The predictions of this theory on the pair production are in very good agreement with the measurements. The calculations of the radiation are in quantitative agreement with measurements for incident angles larger than the channeling critical angle. This agreement is only qualitative for incident angles smaller than the critical angle [fr

Energy dissipation process for 100-MeV protons and the nucleon-nucleon interactions in nuclei

International Nuclear Information System (INIS)

Cowley, A.A.; Chang, C.C.; Holmgren, H.D.; Silk, J.D.; Hendrie, D.L.; Koontz, R.W.; Roos, P.G.; Samanta, C.; Wu, J.R.

1980-01-01

Coincidence studies of two protons emitted from p+ 58 Ni at 100 MeV have been carried out. The proton spectra in coincidence with scattered protons suffering an average energy loss of 60 MeV are similar to those resulting from 60-MeV incident protons. This suggests that the initial interaction of the incident proton is with a bound nucleon and that one or both of these nucleons are emitted or initiates a cascade leading to more complex states

Measurement of {alpha} particle energy loss in biological tissue below 2 MeV

Energy Technology Data Exchange (ETDEWEB)

Stella, S. [Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); National Institute of Nuclear Physics (INFN), Pavia (Italy); Bortolussi, S. [Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); National Institute of Nuclear Physics (INFN), Pavia (Italy)], E-mail: silva.bortolussi@pv.infn.it; Bruschi, P.; Portella, C. [Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); Altieri, S. [Department of Nuclear and Theoretical Physics, University of Pavia, Pavia (Italy); National Institute of Nuclear Physics (INFN), Pavia (Italy)

2009-09-01

The energy loss of {alpha} particles crossing biological tissue at energies between 0.8 and 2.2 MeV has been measured. This energy range is very important for boron neutron capture therapy, based on the {sup 10}B(n,{alpha}){sup 7}Li reaction, which emits {alpha} particles with energies of 1.78 and 1.47 MeV. One of the methods used for the measurement of the boron concentration in tissue is based on the deconvolution of the {alpha} spectra obtained from neutron irradiation of thin (70 {mu}m) tissue samples. For this technique, a knowledge of the behaviour of the energy loss of the particles in the irradiated tissue is of critical importance. In particular, the curve of the residual energy as a function of the distance travelled in the tissue must be known. In this paper, the results of an experiment carried out with an {sup 241}Am source and a series of cryostatic sections of rat-lung tissue are presented. The experimental measurements are compared with the results of Monte Carlo calculations performed with the MCNPX code.

Measurement of the distributions of internuclear separations in 3.0-MeV H2+ and 3.63-MeV HeH+ beams

International Nuclear Information System (INIS)

Kanter, E.P.; Cooney, P.J.; Gemmell, D.S.; Vager, Z.; Pietsch, W.J.; Zabransky, B.J.

1979-01-01

Angular distributions of charged dissociation fragments are measured for 3.0-MeV H 2 + and 3.63-MeV HeH + ions incident on approx. 160 A carbon targets. By using the reflection method for a pure Coulomb potential, there are unfolded from these data the distributions of internuclear separations for each molecular-ion species prior to dissociation. These results are insensitive to ion-source conditions. For H 2 + this distribution, while approx. 2 times wider than a pure ground vibrational state population, is markedly different from the Franck-Condon distribution that has been previously assumed by other authors with similar rf and duo-plasmatron ion sources. For HeH + the distribution is slightly broader (approx. 1.5 times) than that expected for a pure ground state population. From the data, the initial vibrational state population in the incident beam can be extracted. 11 references

Neutron data library for transactinides at energies up to 100 MeV

Energy Technology Data Exchange (ETDEWEB)

Korovin, Y.A.; Artisyuk, V.V.; Konobeyev, A.Y. [Obninsk Institute of Nuclear Power Engineering (Russian Federation)

1995-10-01

New neutron data library for transactinides is briefly described. The library includes evaluated cross-sections for fission and threshold neutron induced reactions for isotopes of U, Np and Pu at energies 0-100 MeV.

Undulator-Based Production of Polarized Positrons, A Proposal for the 50-GeV Beam in the FFTB

Energy Technology Data Exchange (ETDEWEB)

Alexander, G

2004-03-25

The full exploitation of the physics potential of future linear colliders such as the JLC, NLC, and TESLA will require the development of polarized positron beams. In the proposed scheme of Balakin and Mikhailichenko [1] a helical undulator is employed to generate photons of several MeV with circular polarization which are then converted in a relatively thin target to generate longitudinally polarized positrons. This experiment, E-166, proposes to test this scheme to determine whether such a technique can produce polarized positron beams of sufficient quality for use in future linear colliders. The experiment will install a meter-long, short-period, pulsed helical undulator in the Final Focus Test Beam (FFTB) at SLAC. A low-emittance 50-GeV electron beam passing through this undulator will generate circularly polarized photons with energies up to 10 MeV. These polarized photons are then converted to polarized positrons via pair production in thin targets. Titanium and tungsten targets, which are both candidates for use in linear colliders, will be tested. The experiment will measure the flux and polarization of the undulator photons, and the spectrum and polarization of the positrons produced in the conversion target, and compare the measurement results to simulations. Thus the proposed experiment directly tests for the first time the validity of the simulation programs used for the physics of polarized pair production in finite matter, in particular the effects of multiple scattering on polarization. Successful comparison of the experimental results to the simulations will lead to greater confidence in the proposed designs of polarized positrons sources for the next generation of linear colliders. This experiment requests six-weeks of time in the FFTB beam line: three weeks for installation and setup and three weeks of beam for data taking. A 50-GeV beam with about twice the SLC emittance at a repetition rate of 30 Hz is required.

Undulator-Based Production of Polarized Positrons, A Proposal for the 50-GeV Beam in the FFTB

Energy Technology Data Exchange (ETDEWEB)

G. Alexander; P. Anthony; V. Bharadwaj; Yu.K. Batygin; T. Behnke; S. Berridge; G.R. Bower; W. Bugg; R. Carr; E. Chudakov; J.E. Clendenin; F.J. Decker; Yu. Efremenko; T. Fieguth; K. Flottmann; M. Fukuda; V. Gharibyan; T. Handler; T. Hirose; R.H. Iverson; Yu. Kamyshkov; H. Kolanoski; T. Lohse; Chang-guo Lu; K.T. McDonald; N. Meyners; R. Michaels; A.A. Mikhailichenko; K. Monig; G. Moortgat-Pick; M. Olson; T. Omori; D. Onoprienko; N. Pavel; R. Pitthan; M. Purohit; L. Rinolfi; K.P. Schuler; J.C. Sheppard; S. Spanier; A. Stahl; Z.M. Szalata; J. Turner; D. Walz; A. Weidemann; J. Weisend

2003-06-01

The full exploitation of the physics potential of future linear colliders such as the JLC, NLC, and TESLA will require the development of polarized positron beams. In the proposed scheme of Balakin and Mikhailichenko [1] a helical undulator is employed to generate photons of several MeV with circular polarization which are then converted in a relatively thin target to generate longitudinally polarized positrons. This experiment, E-166, proposes to test this scheme to determine whether such a technique can produce polarized positron beams of sufficient quality for use in future linear colliders. The experiment will install a meter-long, short-period, pulsed helical undulator in the Final Focus Test Beam (FFTB) at SLAC. A low-emittance 50-GeV electron beam passing through this undulator will generate circularly polarized photons with energies up to 10 MeV. These polarized photons are then converted to polarized positrons via pair production in thin targets. Titanium and tungsten targets, which are both candidates for use in linear colliders, will be tested. The experiment will measure the flux and polarization of the undulator photons, and the spectrum and polarization of the positrons produced in the conversion target, and compare the measurement results to simulations. Thus the proposed experiment directly tests for the first time the validity of the simulation programs used for the physics of polarized pair production in finite matter, in particular the effects of multiple scattering on polarization. Successful comparison of the experimental results to the simulations will lead to greater confidence in the proposed designs of polarized positrons sources for the next generation of linear colliders. This experiment requests six-weeks of time in the FFTB beam line: three weeks for installation and setup and three weeks of beam for data taking. A 50-GeV beam with about twice the SLC emittance at a repetition rate of 30 Hz is required.

Nuclear photo-meson productions in the 1 GeV energy region

International Nuclear Information System (INIS)

Maeda, Kazushige

1991-01-01

Experimental studies of nuclear photomeson productions in the 1 GeV energy region are discussed. In this energy region, π ± , K + and (η) mesons whose life time (or widths) are enough long (narrow) to use spectroscopic study can be produced. This report focuses a possibility of electro-magnetic K + . productions on nuclei. A preliminary result of a photo-kaon test experiment carried out at electron synchrotron laboratory, Institute for Nuclear Study, University of Tokyo are presented. In this experiment, the particle identification method to select Kaon events has been established. We have performed a first measurement of nuclear photo-kaon cross section. (author)

Rf systems for high-energy e/sup /minus//e/sup /plus// storage rings

International Nuclear Information System (INIS)

Allen, M.A.; Wilson, P.B.

1974-01-01

Electron or positron beams in a storage ring radiate electromagnetic energy at a rate proportional to the fourth power of the recirculating energy, and this loss must be supplied by an rf system. Furthermore, a substantial overvoltage is required to contain the stored beam against losses due to quantum fluctuations in the emitted photons. As an example, an improvement program, SPEAR II, is now underway to increase the energy of the SPEAR ring to 4.5 GeV. At this energy, the radiation loss per turn is 2.8 MeV, and to maintain a reasonable lifetime against quantum fluctuations, a peak voltage of 7.5 MeV is required. Thus, the SPEAR II rf system is similar to a continuously-operating 7.5 MeV linear accelerator. Furthermore, the available straight-section space in the ring which is suitable for containing the accelerating structures is limited, and this means that a cavity design must be sought with a high shunt impedance per losses will be held to a reasonable level. In the case of SPEAR, about 9 meters of straight section space is available for accelerating cavities, requiring a gradient of close to 1 MV per meter. The PEP 15-GeV ring would require peak accelerating voltages of around 50 MV, with about 60 meters of straight-section space available for accelerating structures. 8 refs

Measurement of the {pi}{sup +} p and {pi}{sup -} p total cross-section from 700 to 1700 MeV, and applications to the dispersion relationships; Mesure des sections efficaces totales {pi}{sup +} p et {pi}{sup -} p entre 700 a 1700 MeV et applications aux relations de dispersion

Energy Technology Data Exchange (ETDEWEB)

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

1966-07-01

The {pi}{sup +} P and {pi}{sup -} P total cross sections have been measured between 500 and 1700 MeV to eliminate discrepancies in the experimental data. These new values have permitted a more precise calculation of the forward dispersion relation. These relations are well satisfied by the experimental data up to 18 GeV for charge exchange scattering. The dispersion relation for the spin-flip amplitude gives an efficient test for the phase-shift analysis solutions. (author) [French] Les sections efficaces totales {pi}{sup +} P et {pi}{sup -} P ont ete mesurees entre 500 et 1700 MeV pour eliminer les divergences qui existaient entre les resultats experimentaux anterieurs. Ces nouvelles valeurs ont permis de preciser le calcul des relations de dispersion vers l'avant. Dans le cas de la diffusion avec echange de charge ces relations sont en bon accord avec les resultats experimentaux entre 0 et 18 GeV. L'application des relations de dispersion vers l'avant a l'amplitude de spin-flip fournit une methode tres sensible pour comparer differentes series de dephasages en fonction de l'energie. (auteur)

Uranium, thorium and bismuth photofission cross sections at high energies

International Nuclear Information System (INIS)

Tavares, O.A.P.

1973-01-01

The U 238 , Th 232 and Bi 209 photofission using nuclear emulsion technique for fission fragments detection is presented. The photofission cross sections were measured using Bremsstrahlung photon which were produced irradiating thin tungsten radiators with electrons accelerated at the energy range from 1,0 to 5,5 GeV in the ''Deutsches Elektronen Synchrotron'' (Hamburg), and aluminium radiator with electrons accelarated at 16,0 GeV in Stanford Linear Accelerator Center. A special revelation technique for nuclear emulsion pellicles loaded with uranium and thorium, allowed the discrimination between alpha particles tracks and fission fragments tracks. The results show a decrease in the cross sections, which is in good agreement, within experimental errors, with the conclusions of other authors. The estimations from the two-step mechanism for high energy nuclear reactions (intranuclear cascade followed by fission-evaporation competition) show that, the primary interaction according to the photomesonic model and the quasi-deuteron photon interaction are sufficient to explain the general behavior exhibited by photofission cross sections for investigated nuclei. The calculations show a resonant structure around 300 MeV, with a width at half maximum of 200 MeV, and another not so pronounced, near to 700 MeV. (Author) [pt

The Energy Dependence of Flow in Ni Induced Collisions from 400A to 1970A MeV

International Nuclear Information System (INIS)

Chance, J.; Brady, F.; Cebra, D.; Kintner, J.; Partlan, M.; Romero, J.; Albergo, S.; Caccia, Z.; Costa, S.; Insolia, A.; Potenza, R.; Romanski, J.; Russo, G.; Tuve, C.; Bieser, F.; Cebra, D.; Lisa, M.; Matis, H.; McMahan, M.; McParland, C.; Olson, D.; Rai, G.; Rasmussen, J.; Ritter, H.; Symons, T.; Wieman, H.; Wienold, T.; Choi, Y.; Elliott, J.; Gilkes, M.; Hauger, J.; Hirsch, A.; Hjort, E.; Porile, N.; Scharenberg, R.; Srivastava, B.; Tincknell, M.; Warren, P.; Chacon, A.; Wolf, K.

1997-01-01

We study the energy dependence of collective (hydrodynamic-like) nuclear matter flow in (400 endash 1970)A MeV Ni+Au and (1000 endash 1970)A MeV Ni+Cu reactions. The flow increases with energy, appears to reach a maximum, and then to decrease at higher energies. A way of comparing the energy dependence of flow values for different projectile-target mass combinations is introduced, which demonstrates a more-or-less common scaling behavior among flow values from different systems. copyright 1997 The American Physical Society

Determination of the nuclear incompressibility from the rapidity-dependent elliptic flow in heavy-ion collisions at beam energies 0.4A-1.0A GeV

Science.gov (United States)

Wang, Yongjia; Guo, Chenchen; Li, Qingfeng; Le Fèvre, Arnaud; Leifels, Yvonne; Trautmann, Wolfgang

2018-03-01

Background: The nuclear incompressibility (K0) plays a crucial role in understanding diverse phenomena in nuclear structure and reactions, as well as in astrophysics. Heavy-ion-collision measurements in combination with transport model simulations serve as important tools for extracting the nuclear incompressibility. However, uncertainties in transport models (or model dependence) partly affect the reliability of the extracted result. Purpose: In the present work, by using the recently measured data of rapidity-dependent flows, we constrain the incompressibility of nuclear matter and analyze the impact of model uncertainties on the obtained value. Method: The method is based on the newly updated version of the ultrarelativistic quantum molecular dynamics (UrQMD) model in which the Skyrme potential energy-density functional is introduced. Three different Skyrme interactions which give different incompressibilities varying from K0 = 201 to 271 MeV are adopted. The incompressibility is deduced from the comparison of the UrQMD model simulations and the FOPI data for rapidity-dependent elliptic flow in Au + Au collisions at beam energies 0.4A-1.0A GeV. Results: The elliptic flow v2 as a function of rapidity y0 can be well described by a quadratic fit v2 =v20 +v22 ṡ y02 . It is found that the quantity v2n defined by v2n = |v20 | + |v22 | is quite sensitive to the incompressibility K0 and the in-medium nucleon-nucleon cross section, but not sensitive to the slope parameter L of the nuclear symmetry energy. Conclusions: With the FU3FP4 parametrization of the in-medium nucleon-nucleon cross section, an averaged K0 = 220 ± 40 MeV is extracted from the v2n of free protons and deuterons. However, remaining systematic uncertainties, partly related to the choice of in-medium nucleon-nucleon cross sections, are of the same magnitude (± 40 MeV). Overall, the rapidity dependent elliptic flow supports a soft symmetric-matter equation-of-state.

High energy electron acceleration with PW-class laser system

International Nuclear Information System (INIS)

Nakanii, N.; Kondo, K.; Yabuuchi, T.; Tsuji, K.; Kimura, K.; Fukumochi, S.; Kashihara, M.; Tanimoto, T.; Nakamura, H.; Ishikura, T.; Kodama, R.; Mima, K.; Tanaka, K. A.; Mori, Y.; Miura, E.; Suzuki, S.; Asaka, T.; Yanagida, K.; Hanaki, H.; Kobayashi, T.

2008-01-01

We performed electron acceleration experiment with PW-class laser and a plasma tube, which was created by imploding a hollow polystyrene cylinder. In this experiment, electron energies in excess of 600 MeV have been observed. Moreover, the spectra of a comparatively high-density plasma ∼10 19 cm -3 had a bump around 10 MeV. Additionally, we performed the absolute sensitivity calibration of imaging plate for 1 GeV electrons from the injector Linac of Spring-8 in order to evaluate absolute number of GeV-class electrons in the laser acceleration experiment

Behaviour of the ZEUS uranium-scintillator calorimeter for low-energetic particles with energies of 0.2 - 10.0 GeV

International Nuclear Information System (INIS)

Fuertjes, A.

1990-02-01

A prototype for the high-resolution calorimeter (FCAL) of the ZEUS detector was tested at a test beam of the CERN PS for beam momenta between 0.5 GeV/c and 10.0 GeV/c. The response of the calorimeter to low-energetic electrons, positrons, pions of both polarities, and protons should be studied. Additionally the effect of dead matter in front of the calorimeter was experimentally studied. Following results could be determined: Electrons and Positrons of equal energy produce comparable signals in the detector. Their response is in the considered momentum range with an accuracy of below 1% linear. The energy resolution of the calorimeter for electrons and positrons in the studied energy interval amounts to 17.5%√E. The response of the calorimeter to π + and π - is similar down to momenta of 0.5 GeV/c. The e/π ratio reaches the value 1.0 for energies above 2 GeV. For small incident energies e/mip=0.62 result. The energy resolution for pions amounts for energies above 2 GeV about 34%/√E. For smaller particle energies improvements can be observed. Protons show an identical behaviour as the pions, if the interesting quantities are considered in dependence on their kinetic energy. Dead matter in the front of the calorimeter influences the particle signals of low-energetic positrons and pions. The pulse-height spectra of electrons remain symmetric, but shift to small values. This behaviour could be confirmed by Monte-Carlo calculations. Pions show a distribution becoming with increasing matter density more asymmetric. At energies up to 2 GeV a significant effect mean values, energy resolution, and e/h ratio can be recognized. Above 2 GeV no important nuisance of the response to positrons and pions can yet be observed. (orig.) [de

Measurement of e+e-→π0π0ψ (3686 ) at √{s } from 4.009 to 4.600 GeV and observation of a neutral charmoniumlike structure

Science.gov (United States)

Ablikim, M.; Achasov, M. N.; Ahmed, S.; Albrecht, M.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Bakina, O.; Baldini Ferroli, R.; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Berger, N.; Bertani, M.; Bettoni, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chai, J.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, X. R.; Chen, Y. B.; Chu, X. K.; Cibinetto, G.; 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.; Dorjkhaidav, O.; Dou, Z. L.; Du, S. X.; Duan, P. F.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Farinelli, R.; Fava, L.; Fegan, S.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. L.; Gao, Y.; Gao, Y. G.; Gao, Z.; Garzia, I.; Goetzen, K.; Gong, L.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, S.; Gu, Y. T.; Guo, A. Q.; Guo, L. B.; Guo, R. P.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Hao, X. Q.; Harris, F. A.; He, K. L.; He, X. Q.; Heinsius, F. H.; Held, T.; Heng, Y. K.; Holtmann, T.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, T.; Hu, Y.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, X. Z.; Huang, Z. L.; Hussain, T.; Ikegami Andersson, W.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, X. S.; Jiang, X. Y.; 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.; Khan, T.; Kiese, P.; Kliemt, R.; Kloss, B.; Koch, L.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kuemmel, M.; Kuhlmann, M.; Kupsc, A.; Kühn, W.; Lange, J. S.; Lara, M.; Larin, P.; Lavezzi, L.; Leithoff, H.; Leng, C.; Li, C.; Li, Cheng; Li, D. M.; Li, F.; Li, F. Y.; Li, G.; Li, H. B.; Li, H. J.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P. L.; Li, P. R.; Li, Q. Y.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; 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.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J. B.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, Ke; Liu, L. D.; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Y. Y.; Liu, Z. A.; Liu, Zhiqing; Long, Y. F.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lyu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, M. M.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Ma, Y. M.; Maas, F. E.; Maggiora, M.; Malik, Q. A.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Mezzadri, G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales Morales, C.; Morello, G.; Muchnoi, N. Yu.; Muramatsu, H.; Musiol, P.; Mustafa, A.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Patteri, P.; Pelizaeus, M.; Pellegrino, J.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Prasad, V.; Qi, H. R.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, J. J.; Qin, N.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Richter, M.; Ripka, M.; Rong, G.; Rosner, Ch.; Ruan, X. D.; Sarantsev, A.; Savrié, M.; Schnier, C.; Schoenning, K.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Song, J. J.; Song, X. Y.; Sosio, S.; Sowa, C.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. H.; Sun, Y. J.; Sun, Y. K.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, G. Y.; Tang, X.; Tapan, I.; Tiemens, M.; Tsednee, B. T.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, Dan; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, W. P.; Wang, X. F.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Wang, Z. Y.; Weber, T.; Wei, D. H.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, L. J.; Wu, Z.; Xia, L.; Xia, Y.; Xiao, D.; Xiao, H.; Xiao, Y. J.; Xiao, Z. J.; Xie, Y. G.; Xie, Y. H.; Xiong, X. A.; Xiu, Q. L.; Xu, G. F.; Xu, J. J.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y. H.; Yang, Y. X.; Ye, M.; Ye, M. H.; Yin, J. H.; You, Z. Y.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yuan, C. Z.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zeng, Y.; Zeng, Z.; Zhang, B. X.; Zhang, B. Y.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. Q.; Zhang, X. Y.; Zhang, Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. T.; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; 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, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhou, Y. X.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zotti, L.; Zou, B. S.; Zou, J. H.; Besiii Collaboration

2018-03-01

Using e+e- collision data collected with the BESIII detector at the BEPCII collider corresponding to an integrated luminosity of 5.2 fb-1 at center-of-mass energies (√{s }) from 4.009 to 4.600 GeV, the process e+e-→π0π0ψ (3686 ) is studied for the first time. The corresponding Born cross sections are measured and found to be half of those of the reaction e+e-→π+π-ψ (3686 ). This is consistent with the expectation from isospin symmetry. Furthermore, the Dalitz plots for π0π0ψ (3686 ) are accordant with those of π+π-ψ (3686 ) at all energy points, and a neutral analog to the structure in π±ψ (3686 ) around 4040 MeV /c2 first observed at √{s }=4.416 GeV is observed in the isospin neutral mode at the same energy.

Measurements of fission product yield in the neutron-induced fission of {sup 238}U with average energies of 9.35 MeV and 12.52 MeV

Energy Technology Data Exchange (ETDEWEB)

Mukerji, Sadhana; Krishnani, Pritam Das; Suryanarayana, Saraswatula Venkat; Naik, Haladhara; Goswami, Ashok [Bhabha Atomic Research Centre, Mumbai (India); Shivashankar, Byrapura Siddaramaiah [Manipal University, Manipal (India); Mulik, Vikas Kaluram [University of Pune, Pune (India)

2014-07-15

The yields of various fission products in the neutron-induced fission of {sup 238}U with the flux-weighted averaged neutron energies of 9.35 MeV and 12.52 MeV were determined by using an off-line gamma ray spectroscopic technique. The neutrons were generated using the {sup 7}Li(p, n) reaction at Bhabha Atomic Research Centre-Tata Institute of Fundamental Research Pelletron facility, Mumbai. The gamma- ray activities of the fission products were counted in a highly-shielded HPGe detector over a period of several weeks to identify the decaying fission products. At both the neutron energies, the fission-yield values are reported for twelve fission product. The results obtained from the present work have been compared with the similar data for mono-energetic neutrons of comparable energy from the literature and are found to be in good agreement. The peak-to-valley (P/V) ratios were calculated from the fission-yield data and were found to decreases for neutron energy from 9.35 to 12.52 MeV, which indicates the role of excitation energy. The effect of the nuclear structure on the fission product-yield is discussed.

Energy spectrum measurement of high power and high energy(6 and 9 MeV) pulsed x-ray source for industrial use

Energy Technology Data Exchange (ETDEWEB)

Takagi, Hiroyuki [Hitachi, Ltd. Power Systems Company, Ibaraki (Japan); Murata, Isao [Graduate School of Engineering, Osaka University, Osaka (Japan)

2016-06-15

Industrial X-ray CT system is normally applied to non-destructive testing (NDT) for industrial product made from metal. Furthermore there are some special CT systems, which have an ability to inspect nuclear fuel assemblies or rocket motors, using high power and high energy (more than 6 MeV) pulsed X-ray source. In these case, pulsed X-ray are produced by the electron linear accelerator, and a huge number of photons with a wide energy spectrum are produced within a very short period. Consequently, it is difficult to measure the X-ray energy spectrum for such accelerator-based X-ray sources using simple spectrometry. Due to this difficulty, unexpected images and artifacts which lead to incorrect density information and dimensions of specimens cannot be avoided in CT images. For getting highly precise CT images, it is important to know the precise energy spectrum of emitted X-rays. In order to realize it we investigated a new approach utilizing the Bayesian estimation method combined with an attenuation curve measurement using step shaped attenuation material. This method was validated by precise measurement of energy spectrum from a 1 MeV electron accelerator. In this study, to extend the applicable X-ray energy range we tried to measure energy spectra of X-ray sources from 6 and 9 MeV linear accelerators by using the recently developed method. In this study, an attenuation curves are measured by using a step-shaped attenuation materials of aluminum and steel individually, and the each X-ray spectrum is reconstructed from the measured attenuation curve by the spectrum type Bayesian estimation method. The obtained result shows good agreement with simulated spectra, and the presently developed technique is adaptable for high energy X-ray source more than 6 MeV.

Fluence-to-absorbed dose conversion coefficients for use in radiological protection of embryo and foetus against external exposure to protons from 100 MeV to 100 GeV

International Nuclear Information System (INIS)

Chen, J.

2006-01-01

In the literature, no conversion coefficients are available for use in radiological protection of embryo and foetus against external exposure to protons. This study used the Monte Carlo code MCNPX to determine mean absorbed doses to the embryo and foetus when the mother is exposed to proton fields. Monoenergetic protons ranging from 100 MeV to 100 GeV were considered. The irradiation geometries include antero-posterior (AP), postero-anterior (PA), lateral (LAT), rotational (ROT) and isotropic (ISO). At each of these standard irradiation geometries, absorbed doses to the foetal brain and body were calculated for the embryo of 8 weeks and the foetus of 3, 6 or 9 months. Proton fluence-to-absorbed dose conversion coefficients were derived for the four prenatal ages. (authors)

High baryon and energy densities achievable in heavy-ion collisions at √{sN N}=39 GeV

Science.gov (United States)

Ivanov, Yu. B.; Soldatov, A. A.

2018-02-01

Baryon and energy densities, which are reached in central Au+Au collisions at collision energy of √{sN N}= 39 GeV, are estimated within the model of three-fluid dynamics. It is shown that the initial thermalized mean proper baryon and energy densities in a sizable central region approximately are nB/n0≈ 10 and ɛ ≈ 40 GeV/fm3, respectively. The study indicates that the deconfinement transition at the stage of interpenetration of colliding nuclei makes the system quite opaque. The final fragmentation regions in these collisions are formed not only by primordial fragmentation fireballs, i.e., the baryon-rich matter passed through the interaction region (containing approximately 30% of the total baryon charge), but also by the baryon-rich regions of the central fireball pushed out to peripheral rapidities by the subsequent almost one-dimensional expansion of the central fireball along the beam direction.

The first acceleration to 300 GeV

CERN Multimedia

CERN PhotoLab

1976-01-01

After the acceleration to 80 GeV in May the 200 GeV energy was attained on June 4, followed by a successful attempt to reach 300 GeV and then 400 GeV by the Council session on June 17. Here at the desk (centre) Boris Milman and Bas de Raad, (right) Pat Mills and a machine operator. Then standing on the back Jacques Althaber, Simon Van der Meer, Hans-Peter Kindermann, Raymond Rausch, John Adams, Klaus Batzner, and still back Antonio Millich, Jim Allaby, Wim Middelkoop, Bo Angerth, Hans Horisberger.

Measurement of cross sections for the scattering of neutrons in the energy range from 2 MeV to 4 MeV with the {sup 15}N(p,n) reaction as neutron source; Messung von Wirkungsquerschnitten fuer die Streuung von Neutronen im Energiebereich von 2 MeV bis 4 MeV mit der {sup 15}N(p,n)-Reaktion als Neutronenquelle

Energy Technology Data Exchange (ETDEWEB)

Poenitz, Erik

2010-04-26

In future nuclear facilities, the materials lead and bismuth can play a more important role than in today's nuclear reactors. Reliable cross section data are required for the design of those facilities. In particular the neutron transport in the lead spallation target of an Accelerator-Driven Subcritical Reactor strongly depends on the inelastic neutron scattering cross sections in the energy region from 0.5 MeV to 6 MeV. In the recent 20 years, elastic and inelastic neutron scattering cross sections were measured with high precision for a variety of elements at the PTB time-of-flight spectrometer. The D(d,n) reaction was primarily used for the production of neutrons. Because of the Q value of the reaction and the available deuteron energies, neutrons in the energy range from 6 MeV to 16 MeV can be produced. For the cross section measurement at lower energies, however, another neutron producing reaction is required. The {sup 15}N(p,n){sup 15}O reaction was chosen, as it allows the production of monoenergetic neutrons with up to 5.7MeV energy. In this work, the {sup 15}N(p,n) reaction was studied with focus on the suitability as a source for monoenergetic neutrons in scattering experiments. This includes the measurement of differential cross sections for the neutron producing reaction and the choice of optimum target conditions. Differential elastic and inelastic neutron scattering cross sections were measured for lead at four energies in the region from 2 MeV to 4 MeV incident neutron energy using the time-of-flight technique. A lead sample with natural isotopic composition was used. NE213 liquid scintillation detectors with well-known detection efficiencies were used for the detection of the scattered neutrons. Angle-integrated cross sections were determined by a Legendre polynomial expansion using least-squares methods. Additionally, measurements were carried out for isotopically pure {sup 209}Bi and {sup 181}Ta samples at 4 MeV incident neutron energy

Studies on effective atomic numbers for photon energy absorption and electron density of some narcotic drugs in the energy range 1 keV-20 MeV

Science.gov (United States)

Gounhalli, Shivraj G.; Shantappa, Anil; Hanagodimath, S. M.

2013-04-01

Effective atomic numbers for photon energy absorption ZPEA,eff, photon interaction ZPI,eff and for electron density Nel, have been calculated by a direct method in the photon-energy region from 1 keV to 20 MeV for narcotic drugs, such as Heroin (H), Cocaine (CO), Caffeine (CA), Tetrahydrocannabinol (THC), Cannabinol (CBD), Tetrahydrocannabivarin (THCV). The ZPEA,eff, ZPI,eff and Nel values have been found to change with energy and composition of the narcotic drugs. The energy dependence ZPEA,eff, ZPI,eff and Nel is shown graphically. The maximum difference between the values of ZPEA,eff, and ZPI,eff occurs at 30 keV and the significant difference of 2 to 33% for the energy region 5-100 keV for all drugs. The reason for these differences is discussed.

Theoretical scenarios for 103 GeV to 1019 GeV

International Nuclear Information System (INIS)

Kaul, R.K.

1996-01-01

Basic dogmas of particle physics are reviewed. Some of their implications beyond the standard model are explored. Higgs sector of the standard model of electroweak interactions is the weakest link in the model. Elementary Higgs field makes the model unnatural beyond about 10 3 GeV. Supersymmetry provides the most attractive framework where in this problem can be addressed. This new symmetry, relating fermions and bosons, is expected to be operative at about 10 3 GeV. In addition, grand unification of the fundamental interactions can be studied consistently only within a supersymmetric formulation. Inclusion of gravity with other interactions leads to supergravity theories, which should emerge as a low energy description of a more fundamental theory, the string-theory. Supersymmetry again is an essential feature of such a theory. Quantum gravity, with its characteristic scale of 10 19 GeV, may well be described by a superstring theory. (author). 28 refs., 1 fig

Search for lepton flavor violation in ep collisions at 300 GeV center of mass energy

International Nuclear Information System (INIS)

Derrick, M.; Krakauer, D.; Magill, S.

1996-08-01

Using the ZEUS detector at the HERA electron-proton collider, we have searched for lepton flavor violation in ep collisions at a center-of-mass energy (√s) of 300 GeV. Events of the type e+p→l+X with a final-state lepton of high transverse momentum, l=μ or τ, were sought. No evidence was found for lepton flavor violation in the combined 1993 and 1994 data samples, for which the integrated luminosities were 0.84 pb -1 for e - p collisions and 2.94 pb -1 for e + p collisions. Limits on coupling vs. mass are provided for leptoquarks and R-parity violating squarks. For flavor violating couplings of electromagnetic strength, we set 95% confidence level lower limits on leptoquark masses between 207 GeV and 272 GeV, depending on the leptoquark species and final-state lepton. For leptoquark masses larger than 300 GeV, limits on flavor-changing couplings are determined, many of which supersede prior limits from rare decay processes. (orig.)

A polarimeter for GeV protons of recirculating synchrotron beams

CERN Document Server

Bauer, F

1999-01-01

A polarimeter for use in recirculating beams of proton synchrotrons with energies from 300 MeV up to several GeV has been developed. The polarimetry is based on the asymmetry measurement of elastic p->p scattering on an internal CH sub 2 fiber target. The forward going protons are detected with two scintillator systems on either side of the beam pipe close to the angle THETA sub f of maximum analyzing power A sub N. Each one operates in coincidence with a broad (DELTA THETA sub b =21.4 deg. ), segmented detector system for the recoil proton of kinematically varying direction THETA sub b; this position resolution is also used for a concurrent measurement of the p->C and nonelastic p->p background. The CH sub 2 fiber can be replaced by a carbon fiber for detailed background studies; 'false' asymmetries are accounted for with a rotation of the polarimeter around the beam axis. Polarimetry has been performed in the internal beam of the Cooler Synchrotron COSY at fixed energies as well as during proton acceleratio...

Irradiation of optically activated SI-GaAs high-voltage switches with low and high energy protons

CERN Document Server

Bertolucci, Ennio; Mettivier, G; Russo, P; Bisogni, M G; Bottigli, U; Fantacci, M E; Stefanini, A; Cola, A; Quaranta, F; Vasanelli, L; Stefanini, G

1999-01-01

Semi-Insulating Gallium Arsenide (SI-GaAs) devices have been tested for radiation hardness with 3-4 MeV or 24 GeV proton beams. These devices can be operated in dc mode as optically activated electrical switches up to 1 kV. Both single switches (vertical Schottky diodes) and multiple (8) switches (planar devices) have been studied, by analyzing their current-voltage (I-V) reverse characteristics in the dark and under red light illumination, both before and after irradiation. We propose to use them in the system of high-voltage (-600 V) switches for the microstrip gas chambers for the CMS experiment at CERN. Low energy protons (3-4 MeV) were used in order to produce a surface damage below the Schottky contact: their fluence (up to 2.6*10/sup 15/ p/cm/sup 2/) gives a high-dose irradiation. The high energy proton irradiation (energy: 24 GeV, fluence: 1.1*10/sup 14/ p/cm/sup 2/) reproduced a ten years long proton exposure of the devices in CMS experiment conditions. For low energy irradiation, limited changes of ...

Digital neutron/gamma discrimination with an organic scintillator at energies between 1 MeV and 100 MeV

Energy Technology Data Exchange (ETDEWEB)

Comrie, A.C. [Department of Physics, University of Cape Town, Rondebosch 7700 (South Africa); Buffler, A., E-mail: andy.buffler@uct.ac.za [Department of Physics, University of Cape Town, Rondebosch 7700 (South Africa); Smit, F.D. [iThemba LABS, Somerset West 7129 (South Africa); Wörtche, H.J. [INCAS" 3, Dr. Nassaulaan 9. 9400 AT Assen (Netherlands)

2015-02-01

Three different digital implementations of pulse shape discrimination for pulses from an EJ301 liquid scintillator detector are presented, and illustrated with neutrons and gamma-rays produced by an Am–Be radioisotopic source, a D–T generator and beams produced by cyclotron-accelerated protons of energies 42, 62 and 100 MeV on a Li target. A critical comparison between the three methods is provided.

Code package for calculation of damage effects of medium-energy protons in metal targets

International Nuclear Information System (INIS)

Coulter, C.A.

1976-12-01

A program package was developed to calculate radiation damage effects produced in a metal target by protons in the 100-MeV to 3.5-GeV energy range. A detailed description is given of the control cards and data cards required to use the code package

Measurement of energy deposition distributions produced in cylindrical geometry by irradiation with 15 MeV neutrons

International Nuclear Information System (INIS)

Brandan, M.E.

1979-01-01

Cellular survival experiments have shown that the biological damage induced by radiation depends on the density of energy deposition along the trajectory of the ionizing particle. The quantity L is defined to measure the density of energy transfer along a charged particle's trajectory. It is equal to sigma/l, where sigma is the energy transferred to a medium and l is the path length along which the transfer takes place. L is the stochastic quantity whose mean value is the unrestricted linear energy transfer, L/sub infinity/. Measurements of the distribution of L in a thin medium by secondary charged particles from fast neutron irradiation were undertaken. A counter operating under time coincidence between two coaxial cylindrical detectors was designed and built for this purpose. Secondary charged particles enter a gas proportional counter and deposit some energy sigma. Those particles traversing the chamber along a radial trajectory strike a CsI scintillator. A coincidence between both detectors' signals selects a known path length for these events, namely the radius of the cavity. Measurements of L distributions for l = 1 μm in tissue were obtained for 3 and 15 MeV neutron irradiation of a tissue-equivalent target wall and for 15 MeV neutron irradiation of a graphite wall. Photon events were corrected for by measurements with a Pb target wall and 15 MeV neutron irradiation as well as exposure to a pure photon field. The measured TE wall distributions with 15 MeV neutron bombardment show contributions from protons, α-particles, 9 Be and 12 C recoils. The last three comprise the L distribution for irradiation of the graphite wall. The proton component of the measured L distributions at 3 and 15 MeV was compared to calculated LET distributions

YAP(Ce) crystal characterization with proton beam up to 60 MeV

Energy Technology Data Exchange (ETDEWEB)

Randazzo, N. [Istituto Nazionale di Fisica Nucleare, Sezione di Catania (I), Via S. Sofia, 64-I-95123 Catania (Italy)], E-mail: nunzio.randazzo@ct.infn.it; Sipala, V.; Aiello, S. [Istituto Nazionale di Fisica Nucleare, Sezione di Catania (I), Via S. Sofia, 64-I-95123 Catania (Italy); Lo Presti, D. [Istituto Nazionale di Fisica Nucleare, Sezione di Catania (I), Via S. Sofia, 64-I-95123 Catania (Italy); Dipartimento di Fisica e Astronomia, Universita di Catania, Catania (Italy); Cirrone, G.A.P.; Cuttone, G.; Di Rosa, F. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud (Italy)

2008-02-21

A YAP(Ce) crystal was characterized with a proton beam up to 60 MeV. Tests were performed to investigate the possibility of using this detector as a proton calorimeter. The size of the crystal was chosen so that the proton energy is totally lost inside the medium. The authors propose to use the YAP(Ce) crystal in medical applications for proton therapy. In particular, in proton computed tomography (pCT) project it is necessary as a calorimeter in order to measure the proton residual energy after the phantom. Energy resolution, linearity, and light yield were measured in the Laboratori Nazionali del Sud with the CATANA proton beam [ (http://www.lns.infn.it/CATANA/CATANA)] and the results are shown in this paper. The crystal shows a good resolution (3% at 60 MeV proton beam) and it shows good linearity for different proton beam energies (1% at 30-60 MeV energy range). The crystal performances confirm that the YAP(Ce) crystal represents a good solution for these kinds of application.

YAP(Ce) crystal characterization with proton beam up to 60 MeV

International Nuclear Information System (INIS)

Randazzo, N.; Sipala, V.; Aiello, S.; Lo Presti, D.; Cirrone, G.A.P.; Cuttone, G.; Di Rosa, F.

2008-01-01

A YAP(Ce) crystal was characterized with a proton beam up to 60 MeV. Tests were performed to investigate the possibility of using this detector as a proton calorimeter. The size of the crystal was chosen so that the proton energy is totally lost inside the medium. The authors propose to use the YAP(Ce) crystal in medical applications for proton therapy. In particular, in proton computed tomography (pCT) project it is necessary as a calorimeter in order to measure the proton residual energy after the phantom. Energy resolution, linearity, and light yield were measured in the Laboratori Nazionali del Sud with the CATANA proton beam [ (http://www.lns.infn.it/CATANA/CATANA)] and the results are shown in this paper. The crystal shows a good resolution (3% at 60 MeV proton beam) and it shows good linearity for different proton beam energies (1% at 30-60 MeV energy range). The crystal performances confirm that the YAP(Ce) crystal represents a good solution for these kinds of application

YAP(Ce) crystal characterization with proton beam up to 60 MeV

Science.gov (United States)

Randazzo, N.; Sipala, V.; Aiello, S.; Lo Presti, D.; Cirrone, G. A. P.; Cuttone, G.; Di Rosa, F.

2008-02-01

A YAP(Ce) crystal was characterized with a proton beam up to 60 MeV. Tests were performed to investigate the possibility of using this detector as a proton calorimeter. The size of the crystal was chosen so that the proton energy is totally lost inside the medium. The authors propose to use the YAP(Ce) crystal in medical applications for proton therapy. In particular, in proton computed tomography (pCT) project it is necessary as a calorimeter in order to measure the proton residual energy after the phantom. Energy resolution, linearity, and light yield were measured in the Laboratori Nazionali del Sud with the CATANA proton beam [ http://www.lns.infn.it/CATANA/CATANA] and the results are shown in this paper. The crystal shows a good resolution (3% at 60 MeV proton beam) and it shows good linearity for different proton beam energies (1% at 30-60 MeV energy range). The crystal performances confirm that the YAP(Ce) crystal represents a good solution for these kinds of application.

Study of the Solar Anisotropy for Cosmic Ray Primaries of about 200 GeV Energy with the L3+C Muon Detector

CERN Document Server

Achard, P; Aguilar-Benitez, M; van den Akker, M; Alcaraz, J; Alemanni, G; Allaby, J; Aloisio, A; Alviggi, M G; Anderhub, H; Andreev, Valery P; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Bajo, A; Baksay, G; Baksay, L; Bahr, J; Baldew, S V; Banerjee, S; Banerjee, Sw; Barczyk, A; Barillere, 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; Bohm, 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, M; Chiarusi, T; 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; de la Cruz, B; Cucciarelli, S; van Dalen, J; de Asmundis, R; Deglon, P; Debreczeni, J; Degre, A; Dehmelt, K; Deiters, K; della Volpe, D; Delmeire, E; Denes, P; DeNotaristefani, F; De Salvo, A; Diemoz, M; Dierckxsens, M; Ding, L K; Dionisi, C; Dittmar, M; Doria, A; Dova, M T; Duchesneau, D; Duda, M; Duran, I; Echenard, B; Eline, A; El Hage, A; El Mamouni, H; Engler, A; Eppling, F J; Extermann, P; Faber, G; Falagan, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, M; Ferguson, T; Fesefeldt, H; Fiandrini, E; Field, J H; Filthaut, F; Fisher, W; Fisk, I; Forconi, G; Freudenreich, K; Furetta, C; Galaktionov, Iouri; Ganguli, S N; Garcia-Abia, Pablo; Gataullin, M; Gentile, S; Giagu, S; Gong, Z F; Grabosch, H J; Grenier, G; Grimm, O; Groenstege, H; Gruenewald, M W; Guida, M; Guo, Y N; Gupta, S; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Haller, Ch; Hatzifotiadou, D; Hayashi, Y; He, Z X; Hebbeker, T; Herve, Alain; Hirschfelder, J; Hofer, H; Hohlmann, M; Holzner, G; Hou, S R; Huo, A X; Hu, Y; Ito, N; Jin, B N; Jing, C L; Jones, Lawrence W; de Jong, P; Josa-Mutuberria, I; Kantserov, V; Kaur, M; Kawakami, S; Kienzle-Focacci, M N; Kim, J K; Kirkby, Jasper; Kittel, W; Klimentov, A; Konig, A C; Kok, E; Korn, A; Kopal, M; Koutsenko, V; Kraber, M; Kuang, H H; Kraemer, R W; Kruger, A; Kuijpers, J; Kunin, A; Ladron de Guevara, P; Laktineh, I; Landi, G; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Lei, Y; Leich, H; Leiste, R; Levtchenko, M; Levtchenko, P; Li, C; Li, L; Li, Z C; Likhoded, S; Lin, C H; Lin, W T; Linde, F L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lu, Y S; Luci, C; Luminari, L; Lustermann, W; Ma, W G; Ma, X H; Ma, Y Q; Malgeri, L; Malinin, A; Mana, C; Mans, J; Martin, J P; Marzano, F; Mazumdar, K; McNeil, R R; Mele, S; Meng, X W; Merola, L; Meschini, M; Metzger, W J; Mihul, A; van Mil, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Monteleoni, B; Muanza, y G S; Muijs, A J M; Musicar, B; Musy, M; Nagy, S; Nahnhauer, R; Naumov, V A; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Nisati, A; Novak, T; Kluge, Hannelies; Ofierzynski, R; Organtini, G; Pal, I; Palomares, C; Paolucci, P; Paramatti, R; Parriaud, J -F; Passaleva, G; Patricelli, S; Paul, Thomas Cantzon; Pauluzzi, M; Paus, C; Pauss, F; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pieri, M; Pioppi, M; Piroue, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pojidaev, V; Pothier, J; Prokofev, D; Quartieri, J; Qing, C R; Rahal-Callot, G; Rahaman, Mohammad Azizur; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A; Ravindran, K C; Razis, P; Ren, D; Rescigno, M; Reucroft, S; Rewiersma, P; Riemann, y S; Riles, Keith; Roe, B P; Rojkov, A; Romero, L; Rosca, A; Rosemann, C; Rosenbleck, C; Rosier-Lees, S; Roth, Stefan; Rubio, J A; Ruggiero, G; Rykaczewski, H; Saidi, R; Sakharov, A; Saremi, S; Sarkar, S; Salicio, J; Sanchez, E; Schafer, C; Schegelsky, V; Schmitt, V; Schoeneich, B; Schopper, H; Schotanus, D J; Sciacca, C; Servoli, L; Shen, C Q; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A; Son, D; Souga, C; Spillantini, P; Steuer, M; Stickland, D P; Stoyanov, B; Straessner, A; Sudhakar, K; Sulanke, H; Sultanov, G; Sun, L Z; Sushkov, S; Suter, H; Swain, J D; Szillasi, Z; Tang, X W; Tarjan, P; Tauscher, L; Taylor, L; Tellili, B; Teyssier, D; Timmermans, Charles; Ting, Samuel C C; Ting, S M; Tonwar, S C; Toth, J; Trowitzsch, G; Tully, C; Tung, K L; Ulbricht, J; Unger, M; Valente, E; Verkooijen, H; Van de Walle, R T; Vasquez, R; Veszpremi, V; Vesztergombi, G; Vetlitsky, I; Vicinanza, D; Viertel, G; Villa, S; Vivargent, M; Vlachos, S; Vodopianov, I; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Wadhwa, M; Wang, R G; Wang, Q; Wang, X L; Wang, X W; Wang, Z M; Weber, M; van Wijk, R; Wijnen, T A M; Wilkens, H; Wynhoff, S; Xia, L; Xu, Y P; Xu, J S; Xu, Z Z; Yamamoto, J; Yang, B Z; Yang, C G; Yang, H J; Yang, M; Yang, X F; Yao, Z G; Yeh, S C; Yu, Z Q; Zalite, An; Zalite, Yu; Zhang, C; Zhang, F; Zhang, J; Zhang, S; Zhang, Z P; Zhao, J; Zhou, S J; Zhu, G Y; Zhu, R Y; Zhuang, H L; Zhu, Q Q; Zichichi, A; Zimmermann, B; Zoller, M; Zwart, A N M

2008-01-01

Primary cosmic rays experience multiple deflections in the nonuniform galactic and heliospheric magnetic fields which may generate anisotropies. A study of anisotropies in the energy range between 100 and 500 GeV is performed. This energy range is not yet well explored. The L3 detector at the CERN electron-positron collider, LEP, is used for a study of the angular distribution of atmospheric muons with energies above 20 GeV. This distribution is used to investigate the isotropy of the time-dependent intensity of the primary cosmic-ray flux with a Fourier analysis. A small deviation from isotropy at energies around 200 GeV is observed for the second harmonics at the solar frequency. No sidereal anisotropy is found at a level above 10^-4. The measurements have been performed in the years 1999 and 2000.

Elastic scattering of 16O+16O at energies E/A between 5 and 8 MeV

International Nuclear Information System (INIS)

Nicoli, M. P.; Haas, F.; Freeman, R. M.; Aissaoui, N.; Beck, C.; Elanique, A.; Nouicer, R.; Morsad, A.; Szilner, S.; Basrak, Z.

1999-01-01

The elastic scattering of 16 O+ 16 O has been measured at nine energies between E lab =75 and 124 MeV. The data cover up to 100 degree sign in the c.m. and can be described in terms of phenomenological and folding model potentials which reproduce the main features observed. In agreement with studies at higher energies in this and similar systems, refractive effects are present in the angular distributions at all energies. In particular, the passage of Airy minima through 90 degree sign at E c.m. =40, 47.5, and 62 MeV explains the deep minima observed in the excitation function. The real part of the optical potential is found to vary very little with energy over the studied interval, but the imaginary part shows a rapid change in its shape at incident energy about 90 MeV. Nonetheless, the energy dependence of the volume integral of the real and imaginary parts is in agreement with dispersion relation predictions. (c) 1999 The American Physical Society

GeV Detection of HESS J0632+057

Energy Technology Data Exchange (ETDEWEB)

Li, Jian; Torres, Diego F.; Wilhelmi, Emma de Oña [Institute of Space Sciences (CSIC–IEEC), Campus UAB, Carrer de Magrans s/n, E-08193 Barcelona (Spain); Cheng, K.-S. [Department of Physics, University of Hong Kong, Pokfulam Road, Hong Kong (China); Kretschmar, Peter [European Space Astronomy Centre (ESA/ESAC), Science Operations Department, Villanueva de la Cañada (Madrid) (Spain); Hou, Xian [Yunnan Observatories, Chinese Academy of Sciences, 396 Yangfangwang, Guandu District, Kunming 650216 (China); Takata, Jumpei, E-mail: jian@ice.csic.es [School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China)

2017-09-10

HESS J0632+057 is the only gamma-ray binary that has been detected at TeV energies, but not at GeV energies yet. Based on nearly nine years of Fermi Large Area Telescope (LAT) Pass 8 data, we report here on a deep search for the gamma-ray emission from HESS J0632+057 in the 0.1–300 GeV energy range. We find a previously unknown gamma-ray source, Fermi J0632.6+0548, spatially coincident with HESS J0632+057. The measured flux of Fermi J0632.6+0548 is consistent with the previous flux upper limit on HESS J0632+057 and shows variability that can be related to the HESS J0632+057 orbital phase. We propose that Fermi J0632.6+0548 is the GeV counterpart of HESS J0632+057. Considering the Very High Energy spectrum of HESS J0632+057, a possible spectral turnover above 10 GeV may exist in Fermi J0632.6+0548, as appears to be common in other established gamma-ray binaries.

Alpha particles from the photodisintegration of 9Be in the photon energy region 18 to 26 MeV

International Nuclear Information System (INIS)

Buchnea, A.; Johnson, R.G.; McNeill, K.G.

1978-01-01

Alpha particles from the 9 Be(γ,n) 8 Be(16.6) and 9 Be(γ,α 0 ) 5 He reactions were studied in the photon energy region 18 to 26 MeV; the results yielded a combined integrated cross section of 13.1 +- 2 MeV mb and an upper limit on the integrated (γ,α 0 ) cross section of 4.0 MeV mb. This agrees within error with the integrated cross section of Becchi, Meneghetti, Sanzone, and Vitale, 10 +- 2 MeV mb, which would contain about 50% of any contribution from the (γ,α 0 ) reaction. These reactions together with the 9 Be(γ,n 1 ) 8 Be reaction (which has an integrated cross section of 2.4 +- 0.4 MeV mb) are the major reaction channels contributing to the total photoneutron cross section in this energy region. Their sum, 15.5 MeV mb, agrees well with the results of Nathans and Halpern and Hughes, Sambell, Muirhead, and Spicer but disagrees with that of Costa, Pasqualini, Piragino, and Roasio. (author)

Energy dependence of pi, p and pbar transverse momentum spectra for Au+Au collisions at sqrt sNN = 62.4 and 200 GeV

Energy Technology Data Exchange (ETDEWEB)

Ritter, H

2007-03-26

We study the energy dependence of the transverse momentum (pT) spectra for charged pions, protons and anti-protons for Au+Au collisions at sqrt sNN = 62.4 and 200 GeV. Data are presented at mid-rapidity (lbar y rbar< 0.5) for 0.2< pT< 12 GeV/c. In the intermediate pT region (2< pT< 6 GeV/c), the nuclear modification factor is higher at 62.4 GeV than at 200 GeV, while at higher pT (pT> 7 GeV/c) the modification is similar for both energies. The p/pi+ and pbar/pi- ratios for central collisions at sqrt sNN = 62.4 GeV peak at pT _~;; 2 GeV/c. In the pT range where recombination is expected to dominate, the p/pi+ ratios at 62.4 GeV are larger than at 200 GeV, while the pbar/pi- ratios are smaller. For pT> 2 GeV/c, the pbar/pi- ratios at the two beam energies are independent of pT and centrality indicating that the dependence of the pbar/pi- ratio on pT does not change between 62.4 and 200 GeV. These findings challenge various models incorporating jet quenching and/or constituent quark coalescence.

Elastic and inelastic scattering of α particles at 41MeV and elastic scattering of 3He at 46MeV on 27Al, 28Si, 29Si, and 30Si

International Nuclear Information System (INIS)

Mariolopoulos, Georges.

1976-01-01

Elastic and inelastic scattering of α particles at 41MeV has been studied on 27 Al, 28 Si, 29 Si and 30 Si between 30 and 160deg c.m. The elastic cross section for α particles on 28 Si shows more oscillation than that for the other targets in the region between 80 and 160deg c.m. The data have been analyzed using both a 9 parameters optical model potential and a coupled channel code. In order to investigate the assumption that the abnormal cross section of 28 Si is due to a cluster effect, the 27 Al, 28 Si, 29 Si, 30 Si( 3 He, 3 He) reaction have been studied between 30 and 110deg c.m., using a 46MeV beam. In this case the angular distributions of the three Si isotopes are similar. An optical model analysis of the data reveals no anomaly [fr

Limit on possible energy-dependent velocities for massless particles

International Nuclear Information System (INIS)

Haines, T.J.; Alexandreas, D.E.; Allen, R.C.; Biller, S.; Berley, D.; Burman, R.L.; Cady, D.R.; Chang, C.Y.; Dingus, B.L.; Dion, G.M.; Ellsworth, R.W.; Goodman, J.A.; Hoffman, C.M.; Lloyd-Evans, J.; Nagle, D.E.; Potter, M.; Sandberg, V.D.; Wilkinson, C.A.; Yodh, G.B.

1990-01-01

A basic tenet of special relativity is that all massless particles travel at a constant, energy-independent velocity. Astrophysical data, including observation of the Crab pulsar at ∼100 MeV and the recent detection of the pulsar in Hercules X-1 at energies ≥100 TeV, are used to place new experimental constraints on energy-dependent deviations from constant velocity for massless particles. Previous experiments reached energies ∼10 GeV; this analysis improves the previous constraints by 7 orders of magnitude

Shower development of particles with momenta from 15 GeV to 150 GeV in the CALICE scintillator-tungsten hadronic calorimeter

CERN Document Server

Chefdeville, M.; Repond, J.; Schlereth, J.; Xia, L.; Eigen, G.; Marshall, J.S.; Thomson, M.A.; Ward, D.R.; Alipour Tehrani, N.; Apostolakis, J.; Dannheim, D.; Elsener, K.; Folger, G.; Grefe, C.; Ivantchenko, V.; Killenberg, M.; Klempt, W.; van der Kraaij, E.; Linssen, L.; Lucaci-Timoce, A.-I.; Münnich, A.; Poss, S.; Ribon, A.; Roloff, P.; Sailer, A.; Schlatter, D.; Sicking, E.; Strube, J.; Uzhinskiy, V.; Chang, S.; Khan, A.; Kim, D.H.; Kong, D.J.; Oh, Y.D.; Blazey, G.C.; Dyshkant, A.; Francis, K.; Zutshi, V.; Giraud, J.; Grondin, D.; Hostachy, J.-Y.; Brianne, E.; Cornett, U.; David, D.; Falley, G.; Gadow, K.; Göttlicher, P.; Günter, C.; Hartbrich, O.; Hermberg, B.; Irles, A.; Karstensen, S.; Krivan, F.; Krüger, K.; Kvasnicka, J.; Lu, S.; Lutz, B.; Morozov, S.; Morgunov, V.; Neubüser, C.; Provenza, A.; Reinecke, M.; Sefkow, F.; Smirnov, P.; Terwort, M.; Tran, H.L.; Vargas-Trevino, A.; Garutti, E.; Laurien, S.; Matysek, M.; Ramilli, M.; Schröder, S.; Briggl, K.; Eckert, P.; Harion, T.; Munwes, Y.; Schultz-Coulon, H. -Ch.; Shen, W.; Stamen, R.; Bilki, B.; Onel, Y.; Kawagoe, K.; Hirai, H.; Sudo, Y.; Suehara, T.; Sumida, H.; Takada, S.; Tomita, T.; Yoshioka, T.; Wing, M.; Calvo Alamillo, E.; Fouz, M. -C.; Marin, J.; Puerta-Pelayo, J.; Verdugo, A.; Bobchenko, B.; Chadeeva, M.; Danilov, M.; Markin, O.; Mizuk, R.; Novikov, E.; Rusinov, V.; Tarkovsky, E.; Kirikova, N.; Kozlov, V.; Smirnov, P.; Soloviev, Y.; Besson, D.; Buzhan, P.; Popova, E.; Gabriel, M.; Kiesling, C.; van der Kolk, N.; Seidel, K.; Simon, F.; Soldner, C.; Szalay, M.; Tesar, M.; Weuste, L.; Amjad, M.S.; Bonis, J.; Cornebise, P.; Richard, F.; Pöschl, R.; Rouëné, J.; Thiebault, A.; Anduze, M.; Balagura, V.; Boudry, V.; Brient, J-C.; Cizel, J-B.; Cornat, R.; Frotin, M.; Gastaldi, F.; Haddad, Y.; Magniette, F.; Nanni, J.; Pavy, S.; Rubio-Roy, M.; Shpak, K.; Tran, T.H.; Videau, H.; Yu, D.; Callier, S.; Conforti di Lorenzo, S.; Dulucq, F.; Fleury, J.; Martin-Chassard, G.; de la Taille, Ch.; Raux, L.; Seguin-Moreau, N.; Cvach, J.; Gallus, P.; Havranek, M.; Janata, M.; Kovalcuk, M.; Lednicky, D.; Marcisovsky, M.; Polak, I.; Popule, J.; Tomasek, L.; Tomasek, M.; Ruzicka, P.; Sicho, P.; Smolik, J.; Vrba, V.; Zalesak, J.; Ieki, S.; Kamiya, Y.; Ootani, W.; Shibata, N.; Chen, S.; Jeans, D.; Komamiya, S.; Kozakai, C.; Nakanishi, H.; Götze, M.; Sauer, J.; Weber, S.; Zeitnitz, C.

2015-12-10

We present a study of showers initiated by electrons, pions, kaons, and protons with momenta from 15 GeV to 150 GeV in the highly granular CALICE analogue scintillator-tungsten hadronic calorimeter. The data were recorded at the CERN Super Proton Synchrotron in 2011. The analysis includes measurements of the calorimeter response to each particle type as well as measurements of the energy resolution and studies of the longitudinal and radial shower development for selected particles. The results are compared to Geant4 simulations (version 9.6.p02). In the study of the energy resolution we include previously published data with beam momenta from 1 GeV to 10 GeV recorded at the CERN Proton Synchrotron in 2010.

Measurement of Isolated Prompt Photon Production in Photon-Photon Collisions at $\\sqrt{s_{ee}}$=183-209 GeV

CERN Document Server

Abbiendi, G.; Akesson, P.F.; Alexander, G.; Allison, John; Amaral, P.; Anagnostou, G.; Anderson, K.J.; Arcelli, S.; Asai, S.; Axen, D.; Azuelos, G.; Bailey, I.; Barberio, E.; Barlow, R.J.; Batley, R.J.; Bechtle, P.; Behnke, T.; Bell, Kenneth Watson; Bell, P.J.; Bella, G.; Bellerive, A.; Benelli, G.; Bethke, S.; Biebel, O.; Boeriu, O.; Bock, P.; Boutemeur, M.; Braibant, S.; Brigliadori, L.; Brown, Robert M.; Buesser, K.; Burckhart, H.J.; Campana, S.; Carnegie, R.K.; Caron, B.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, David G.; Csilling, A.; Cuffiani, M.; Dado, S.; De Roeck, A.; De Wolf, E.A.; Desch, K.; Dienes, B.; Donkers, M.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Etzion, E.; Fabbri, F.; Feld, L.; Ferrari, P.; Fiedler, F.; Fleck, I.; Ford, M.; Frey, A.; Furtjes, A.; Gagnon, P.; Gary, John William; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Giunta, Marina; Goldberg, J.; Gross, E.; Grunhaus, J.; Gruwe, M.; Gunther, P.O.; Gupta, A.; Hajdu, C.; Hamann, M.; Hanson, G.G.; Harder, K.; Harel, A.; Harin-Dirac, M.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Hensel, C.; Herten, G.; Heuer, R.D.; Hill, J.C.; Hoffman, Kara Dion; Horvath, D.; Igo-Kemenes, P.; Ishii, K.; Jeremie, H.; Jovanovic, P.; Junk, T.R.; Kanaya, N.; Kanzaki, J.; Karapetian, G.; Karlen, D.; Kawagoe, K.; Kawamoto, T.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kim, D.H.; Klein, K.; Klier, A.; Kluth, S.; Kobayashi, T.; Kobel, M.; Komamiya, S.; Kormos, Laura L.; Kramer, T.; Krieger, P.; von Krogh, J.; Kruger, K.; Kuhl, T.; Kupper, M.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Layter, J.G.; Leins, A.; Lellouch, D.; Lettso, J.; Levinson, L.; Lillich, J.; Lloyd, S.L.; Loebinger, F.K.; Lu, J.; Ludwig, J.; Macpherson, A.; Mader, W.; Marcellini, S.; Martin, A.J.; Masetti, G.; Mashimo, T.; Mattig, Peter; McDonald, W.J.; McKenna, J.; McMahon, T.J.; McPherson, R.A.; Meijers, F.; Menges, W.; Merritt, F.S.; Mes, H.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Moed, S.; Mohr, W.; Mori, T.; Mutter, A.; Nagai, K.; Nakamura, I.; Nanjo, H.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oh, A.; Okpara, A.; Oreglia, M.J.; Orito, S.; Pahl, C.; Pasztor, G.; Pater, J.R.; Patrick, G.N.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poli, B.; Polok, J.; Pooth, O.; Przybycien, M.; Quadt, A.; Rabbertz, K.; Rembser, C.; Renkel, P.; Roney, J.M.; Rosati, S.; Rozen, Y.; Runge, K.; Sachs, K.; Saeki, T.; Sarkisyan, E.K.G.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schieck, J.; Schoerner-Sadenius, Thomas; Schroder, Matthias; Schumacher, M.; Schwick, C.; Scott, W.G.; Seuster, R.; Shears, T.G.; Shen, B.C.; Sherwood, P.; Siroli, G.; Skuja, A.; Smith, A.M.; Sobie, R.; Soldner-Rembold, S.; Spano, F.; Stahl, A.; Stephens, K.; Strom, David M.; Strohmer, R.; Tarem, S.; Tasevsky, M.; Taylor, R.J.; Teuscher, R.; Thomson, M.A.; Torrence, E.; Toya, D.; Tran, P.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turner-Watson, M.F.; Ueda, I.; Ujvari, B.; Vollmer, C.F.; Vannerem, P.; Vertesi, R.; Verzocchi, M.; Voss, H.; Vossebeld, J.; Waller, D.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wengler, T.; Wermes, N.; Wetterling, D.; Wilson, G.W.; Wilson, J.A.; Wolf, G.; Wyatt, T.R.; Yamashita, S.; Zer-Zion, D.; Zivkovic, Lidija

2004-01-01

For the first time at LEP the production of prompt photons is studied in the collisions of quasi-real photons using the OPAL data taken at e+e- centre-of-mass energies between 183 GeV and 209 GeV. The total inclusive production cross-section for isolated prompt photons in the kinematic range of photon transverse momentum larger than 3.0 GeV and absolute photon pseudorapidity less than 1 is determined to be 0.32 +- 0.04 (stat) +- 0.04 (sys) pb. Differential cross-sections are compared to the predictions of a next-to-leading-order (NLO) calculation.

Observation of e(+)e(-) -> eta ' J/psi center-of-mass energies between 4.189 and 4.600 GeV

NARCIS (Netherlands)

Ablikim, M.; Achasov, M. N.; Ahmed, S.; 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.; Berger, N.; Bertani, M.; Bettoni, D.; Bian, J. M.; Bianchi, F.; Boger, E.; 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.; Chen, S. J.; Chen, X.; Chen, X. R.; Chen, Y. B.; Cheng, H. P.; Chu, X. K.; Cibinetto, G.; 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.; Dou, Z. L.; Du, S. X.; Duan, P. F.; Fan, J. Z.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Farinelli, R.; Fava, L.; Fedorov, O.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. L.; Gao, X. Y.; Gao, Y.; Gao, Z.; Garzia, I.; Goetzen, K.; Gong, L.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, R. P.; Guo, Y.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Hao, X. Q.; Harris, F. A.; He, K. L.; Heinsius, F. H.; Held, T.; Heng, Y. K.; Holtmann, T.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, X. Z.; Huang, Y.; Huang, Z. L.; Hussain, T.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. W.; Jiang, X. S.; Jiang, X. Y.; 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.; Kiese, P.; Kliemt, R.; Kloss, B.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kupsc, A.; Kuehn, W.; Lange, J. S.; Lara, M.; Larin, P.; Leithoff, H.; Leng, C.; Li, C.; Li, Cheng; Li, D. M.; Li, F.; Li, F. Y.; Li, G.; Li, H. B.; Li, H. J.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P. R.; Li, Q. Y.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, Y. B.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J.; Liu, J. B.; 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, Y. B.; Liu, Y. Y.; Liu, Z. A.; Liu, Zhiqing; Loehner, H.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lyu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, M. M.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Ma, Y. M.; Maas, F. E.; Maggiora, M.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Mezzadri, G.; Min, J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales, C. Morales; Muchnoi, N. Yu.; Muramatsu, H.; Musiol, P.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Prasad, V.; Qi, H. R.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, N.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Ripka, M.; Rong, G.; Rosner, Ch.; Ruan, X. D.; Sarantsev, A.; Savrie, M.; Schnier, C.; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Shi, M.; Song, W. M.; Song, X. Y.; Sosio, S.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. H.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Tiemens, 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, S. G.; Wang, W.; Wang, W. P.; Wang, X. F.; Wang, Y.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Wang, Z. Y.; Weber, T.; Wei, D. H.; Wei, J. B.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, L. J.; Wu, Z.; Xia, L.; Xia, L. G.; Xia, Y.; Xiao, D.; Xiao, H.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, J. J.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y. X.; Ye, M.; Ye, M. H.; Yin, J. H.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zeng, Z.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. Q.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. N.; Zhang, Y. T.; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; 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, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zotti, L.; Zou, B. S.; Zou, J. H.

2016-01-01

The process e(+)e(-) -> eta' J/psi is observed for the first time with a statistical significance of 8.6 sigma at center-of-mass energy root s = 4.226 GeV and 7.3 sigma at root s = 4.258 GeV using data samples collected with the BESIII detector. The Born cross sections are measured to be (3.7 +/-

Calculation of nuclear data for incident energies to 200 MeV with the FKK-GNASH code system

International Nuclear Information System (INIS)

Chadwick, M.B.; Young, P.G.

1993-02-01

We describe how the FKK-GNASH code system has been extended to calculate nucleon-induced reactions up to 200 MeV, and used to predict (p,xn) and (p,xp) cross sections on 208 Pb at incident energies of 25, 45, 80 and 160 MeV, for an intermediate energy code intercomparison. Details of the reaction mechanisms calculated by FKK-GNASH are given, and the calculational procedure is described

Large scale silver nanowires network fabricated by MeV hydrogen (H+) ion beam irradiation

International Nuclear Information System (INIS)

S, Honey; S, Naseem; A, Ishaq; M, Maaza; M T, Bhatti; D, Wan

2016-01-01

A random two-dimensional large scale nano-network of silver nanowires (Ag-NWs) is fabricated by MeV hydrogen (H + ) ion beam irradiation. Ag-NWs are irradiated under H +  ion beam at different ion fluences at room temperature. The Ag-NW network is fabricated by H + ion beam-induced welding of Ag-NWs at intersecting positions. H +  ion beam induced welding is confirmed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Moreover, the structure of Ag NWs remains stable under H +  ion beam, and networks are optically transparent. Morphology also remains stable under H +  ion beam irradiation. No slicings or cuttings of Ag-NWs are observed under MeV H +  ion beam irradiation. The results exhibit that the formation of Ag-NW network proceeds through three steps: ion beam induced thermal spikes lead to the local heating of Ag-NWs, the formation of simple junctions on small scale, and the formation of a large scale network. This observation is useful for using Ag-NWs based devices in upper space where protons are abandoned in an energy range from MeV to GeV. This high-quality Ag-NW network can also be used as a transparent electrode for optoelectronics devices. (paper)

Photon pair production by e/sup +/e/sup -/ annihilation and search for supersymmetric photinos at energies greater than 40 GeV

Energy Technology Data Exchange (ETDEWEB)

Althoff, M; Braunschweig, W; Kirschfink, F J; Luebelsmeyer, K; Martyn, H U; Rosskamp, R; Schmitz, D; Siebke, H; Wallraff, W; Eisenmann, J

1984-12-01

The cross section for the process e/sup +/e/sup -/->..gamma gamma.. has been measured for c.m. energies 39.5 < W < 46.8 GeV. Good agreement with the predictions of QED was found and lower limits for the cut-off parameters of 6 GeV (95% confidence level) have been determined. A search for two photon final states with missing energy provided lower limits on the masses of the photino and selectron.

7-GeV Advanced Photon Source Conceptual Design Report

International Nuclear Information System (INIS)

1987-04-01

During the past decade, synchrotron radiation emitted by circulating electron beams has come into wide use as a powerful, versatile source of x-rays for probing the structure of matter and for studying various physical processes. Several synchrotron radiation facilities with different designs and characteristics are now in regular operation throughout the world, with recent additions in this country being the 0.8-GeV and 2.5-GeV rings of NSLS at Brookhaven National Laboratory. However, none of the operating facilities has been designed to use a low-emittance, high-energy stored beam, together with modern undulator devices, to produce a large number of hard x-ray beams of extremely high brilliance. This document is a proposal to the Department of Energy to construct and operate high-energy synchrotron radiation facility at Argonne National Laboratory. We have now chosen to set the design energy of this facility at 7.0 GeV, with the capability to operate at up to 7.5 GeV

Tensorial analyzing power T20 at 1800C.M. in d vector p elastic scattering between 0.3 and 2.3 GeV

International Nuclear Information System (INIS)

Gaillard, G.

1984-01-01

The results of the measurement of the analysing power T 20 at 180 0 CM in d vector p elastic scattering for 16 energies between 300 and 2300 MeV are presented. The values which have been obtained are badly reproduced by the calculations based on neutron transfer (ONT) and Δ excitation in the intermediate state (TME) mechanisms, principal beyond 1 GeV. The excitation of possible tribaryon resonances, which are introduced in an elementary way, is added to these two mechanisms. The results of these calculations show that one could thus obtain a satisfying agreement with the experimental values. A measurement of angular distribution of the analysing powers Asub(y) and Asub(yy) between 70 and 180 0 CM at 1200 MeV is also presented [fr

Analysis of the energy weighted angular correlations in hadronic e+e- annihilations at 22 and 34 GeV

International Nuclear Information System (INIS)

Behrend, H.J.; Chen, C.; Fenner, H.; Field, J.H.; Schroeder, V.; Sindt, H.; D'Agostini, G.; Apel, W.D.; Banerjee, S.; Bodenkamp, J.

1982-04-01

Measurements of energy weighted angular correlations in electron positron annihilations at c.m. energies of 22 GeV and 34 GeV are presented. The data are compared with perturbative QCD predictions. The theoretical predictions which refer to the partons describe the data reasonably well, depending on the approximations chosen. The effective strong coupling constant αsub(s) has been evaluated using a method where the effect of fragmentation is minimal. At large acolinearity angles QCD calculations going beyond the Leading Double Log approximation appear to be quite successful. The agreement is improved when the smearing effect of heavy resonance decays is taken out of the data. (orig.)

Electronuclear amplifiers with low-energy proton beams

International Nuclear Information System (INIS)

Barashenkov, V.S.; Shelaev, I.A.

1998-01-01

The use of proton accelerators with energy 200-300 MeV in subcritical electronuclear systems seems more preferable in comparison with more complicated and expensive machines with energy about 1 GeV, which are considered as favourite now. Such an approach allows one to build comparatively simple electronuclear plants in particular, for a safety and profitable incineration of plutonium from power plants and spells, in fact, a new strategy of electronuclear technology. Potentialities of the use of low-energy accelerators are illustrated by an electronuclear arrangements designed now in Dubna

Energy dependence of multiplicity fluctuations in heavy ion collisions at 20A to 158A GeV

CERN Document Server

Alt, C.; Baatar, B.; Barna, D.; Bartke, J.; Betev, L.; Bialkowska, Helena; Blume, Christoph; Boimska, B.; Botje, Michiel; Bracinik, J.; Bramm, R.; Buncic, P.; Cerny, V.; Christakoglou, P.; Chung, P.; Chvala, O.; Cramer, J.G.; Csato, P.; Dinkelaker, P.; Eckardt, V.; Flierl, D.; Fodor, Zoltan; Foka, P.; Friese, Volker; Gal, J.; Gazdzicki, Marek; Genchev, V.; Georgopoulos, G.; Gladysz, E.; Grebieszkow, K.; Hegyi, S.; Hohne, C.; Kadija, K.; Karev, A.; Kikola, D.; Kliemant, M.; Kniege, S.; Kolesnikov, V.I.; Kornas, E.; Korus, R.; Kowalski, M.; Kraus, I.; Kreps, M.; Laszlo, A.; Lacey, Roy A.; van Leeuwen, M.; Levai, P.; Litov, Leandar; Makariev, M.; Malakhov, A.I.; Mateev, M.; Melkumov, G.L.; Mischke, A.; Mitrovski, M.; Molnar, J.; Mrowczynski, St.; Nicolic, V.; Palla, G.; Panagiotou, Apostolos D.; Panayotov, D.; Peryt, W.; Pikna, M.; Pluta, J.; Prindle, D.; Puhlhofer, F.; Renfordt, R.; Roland, C.; Roland, Gunther; Rybczynski, M.; Rybicki, A.; Sandoval, Andres; Schmitz, Norbert; Schuster, T.; Seyboth, P.; Sikler, F.; Sitar, B.; Skrzypczak, E.; Slodkowski, M.; Stefanek, Grzegorz; Stock, R.; Strabel, C.; Strobele, H.; Susa, T.; Szentpetery, I.; Sziklai, J.; Szuba, M.; Szymanski, P.; Trubnikov, V.; Utvic, M.; Varga, D.; Vassiliou, M.; Veres, G.I.; Vesztergombi, G.; Vranic, D.; Wetzler, A.; Wlodarczyk, Z.; Wojtaszek, A.; Yoo, I.K.

2008-01-01

Multiplicity fluctuations of positively, negatively and all charged hadrons in the forward hemisphere were studied in central Pb+Pb collisions at 20A, 30A, 40A, 80A and 158A GeV. The multiplicity distributions and their scaled variances $\\omega$ are presented in dependence of collision energy as well as of rapidity and transverse momentum. The distributions have bell-like shape and their scaled variances are in the range from 0.8 to 1.2 without any significant structure in their energy dependence. No indication of the critical point fluctuations are observed. The string-hadronic model UrQMD significantly overpredicts the mean, but approximately reproduces the scaled variance of the multiplicity distributions. The predictions of the statistical hadron-resonance gas model obtained within the grand-canonical and canonical ensembles disagree with the measured scaled variances. The narrower than Poissonian multiplicity fluctuations measured in numerous cases may be explained by the impact of conservation laws on f...

High-energy gamma-ray beams from Compton-backscattered laser light

International Nuclear Information System (INIS)

Sandorfi, A.M.; LeVine, M.J.; Thorn, C.E.; Giordano, G.; Matone, G.

1983-01-01

Collisions of light photons with relativistic electrons have previously been used to produce polarized #betta#-ray beams with modest (-10%) resolution but relatively low intensity. In contrast, the LEGS project (Laser + Electron Gamma Source) at Brookhaven will produce a very high flux (>2 x 10 7 s - 1 ) of background-free polarized #betta# rays whose energy will be determined to a high accuracy (δE = 2.3 MeV). Initially, 300(420)-MeV #betta# rays will be produced by backscattering uv light from the new 2.5(3.0)-GeV X-ray storage ring of the National Synchrotron Light Source (NSLS). The LEGS facility will operate as one of many passive users of the NSLS. In a later stage of the project, a Free Electron Laser is expectred to extend the #betta#-ray energy up to 700 MeV

High-energy gamma-ray beams from Compton-backscattered laser light

Energy Technology Data Exchange (ETDEWEB)

Sandorfi, A.M.; LeVine, M.J.; Thorn, C.E.; Giordano, G.; Matone, G.

1983-01-01

Collisions of light photons with relativistic electrons have previously been used to produce polarized ..gamma..-ray beams with modest (-10%) resolution but relatively low intensity. In contrast, the LEGS project (Laser + Electron Gamma Source) at Brookhaven will produce a very high flux (>2 x 10/sup 7/ s/sup -1/) of background-free polarized ..gamma.. rays whose energy will be determined to a high accuracy (..delta..E = 2.3 MeV). Initially, 300(420)-MeV ..gamma.. rays will be produced by backscattering uv light from the new 2.5(3.0)-GeV X-ray storage ring of the National Synchrotron Light Source (NSLS). The LEGS facility will operate as one of many passive users of the NSLS. In a later stage of the project, a Free Electron Laser is expectred to extend the ..gamma..-ray energy up to 700 MeV.

Intermediate-energy nuclear physics. Task C. Technical progress report, October 1, 1982-October 1, 1983. Part I

International Nuclear Information System (INIS)

1983-01-01

Progress is reported on the following experimental studies: (1) excitation of giant resonances in 118 Sn in inelastic pion scattering at 130 MeV; (2) giant dipole excitations of 40 Ca by inelastic pion scattering; (3) charge symmetry test using the π + and π - elastic scattering from deuterium at 143 and 256 MeV; (4) binding energy effects on the isospin amplitudes in p-shell nuclei; (5) the energy dependence of the 14 C (π + ,π 0 ) 14 N reaction to the IAS; (6) the ( 3 He,t) reaction at 2 GeV; (7) analyzing power in the (polarized p,n) IAS transitions; (8) the excitation of the 1/2 + (2.36) MeV state in the 24Mg (polarized p,d) reaction from 27 to 150 MeV; (9) the energy dependence of the (polarized p,d) reaction for 54 Fe and 140 Ce; and (10) the energy dependence of the 7 Li(p,d) 6 Li reaction. Publications are listed

Response of Inorganic Scintillators to Neutrons of 3 and 15 MeV Energy

CERN Document Server

Lucchini, M; Pizzichemi, M; Chipaux, R; Jacquot, F; Mazue, H; Wolff, H; Lecoq, P; Auffray, E

2014-01-01

In the perspective of the development of future high energy physics experiments, homogeneous calorimeters based on inorganic scintillators can be considered for the detection of hadrons (e.g., calorimeter based on dual-readout technique). Although of high importance in the high energy physics framework as well as for homeland security applications, the response of these inorganic scintillators to neutrons has been only scarcely investigated. This paper presents results obtained using five common scintillating crystals (of size around 2x2x2 cm 3), namely lead tungstate (PbWO4), bismuth germanate (BGO), cerium fluoride (CeF3), Ce-doped lutetium-yttrium orthosilicate (LYSO:Ce) and lutetium aluminum garnet (LuAG:Ce) in a pulsed flux of almost mono-energetic (similar to 3 MeV and similar to 15 MeV) neutrons provided by the Van de Graff accelerator SAMES of CEA Valduc. Energy spectra have been recorded, calibrated and compared with Geant4 simulations computed with different physics models. The neutron detection eff...

Measurement of the neutron-induced fission cross section of 237Np relative to 235U from 0.02 to 30 MeV

International Nuclear Information System (INIS)

Behrens, J.W.; Magana, J.W.; Browne, J.C.

1977-01-01

The 237 Np/ 235 U fission cross section ratio has been measured from 0.02 to 30 MeV. Using the threshold method, a value of 1.294 +- 0.019 is obtained for the average cross section ratio in the interval from 1.75 to 4.00 MeV

Radiation spectra of high-energy electrons in monocrystals of various thickness and orientation

International Nuclear Information System (INIS)

Avakyan, R.O.; Agan'yants, A.O.; Akopov, N.Z.; Vartanov, Yu.A.; Vartapetyan, G.A.; Lebedev, A.N.; Mirzoyan, R.M.; Taroyan, S.P.; Danagulyan, S.S.

1982-01-01

Yield of photons with energies 20-200 MeV at motion of the 4.7 GeV electron beam in parallel to the axis of a diamond crystal exceeds substantially the corresponding yield from a disoriented target. A similarity is observed in the radiation spectra within the crystal thickness range of 100- 610 mkm. The radiation yield is suppressed at certain energies of the γ quanta [ru

Development of neutron-monitor detectors applicable for energies up to 100 MeV

Energy Technology Data Exchange (ETDEWEB)

Sato, Tatsuhiko; Endo, Akira; Yamaguchi, Yasuhiro; Kim, Eunjoo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Nakamura, Takashi [Tohoku Univ., Sendai, Miyagi (Japan)

2003-03-01

For the purpose of monitoring of neutron doses in high energy accelerator facilities, we have been developing neutron detectors which are applicable for neutron energies up to 100 MeV. The present paper reports characteristics of a phoswitch-type neutron detector which is composed of a liquid organic scintillator and {sup 6}Li+ZnS(Ag) sheets. (author)

Deuteron stripping on beryllium target in the 100-2300 MeV energy range

International Nuclear Information System (INIS)

Lecolley, J.F.; Varignon, C.; Durand, D.; Le Brun, C.; Lecolley, F.R.; Lefebvres, F.; Louvel, M.; Thun, J.; Borne, F.; Martinez, E.; Menard, S.; Pras, P.; Boudard, A.; Duchazeaubeneix, J.C.; Durand, J.M.; Frehaut, J.; Hanappe, F.; Ledoux, X.; Legrain, R.; Leray, S.; Milleret, G.; Patin, Y.; Stuttge, L.; Terrien, Y.

1999-01-01

Cross sections for stripping and dissociation of deuterons interacting with Be targets in the 100-2300 MeV energy range have been measured. Comparisons with model calculations suggest a dominant contribution of the stripping process. It is also shown that the deuteron break-up cross section exhibits the same energy dependence as the nucleon-nucleon cross section. (orig.)

The 12 GeV Upgrade at Jefferson Lab

International Nuclear Information System (INIS)

Rolf Ent

2002-01-01

There has been a remarkable fruitful evolution of our picture of the behavior of strongly interacting matter during the almost two decades that have passed since the parameters of the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab were defined. These advances have revealed important new experimental questions best addressed by a CEBAF-class machine at higher energy. Fortunately, favorable technical developments coupled with foresight in the design of the facility make it feasible to triple (double) CEBAF's design (achieved) beam energy from 4 (6) GeV to 12 GeV, in a cost-effective manner: the Upgrade can be realized for about 15% of the cost of the initial facility. This Upgrade would enable the worldwide community to greatly expand its physics horizons. In addition to in general improving the figure of merit and momentum transfer range of the present Jefferson Lab physics program, raising the energy of the accelerator to 12 GeV opens up two main new areas of physics: (1) It allows direct exploration of the quark-gluon structure of hadrons and nuclei in the ''valence quark region''. It is known that inclusive electron scattering at the high momentum and energy transfers available at 12 GeV is governed by elementary interactions with quarks and, indirectly, gluons. The original CEBAF energy is not adequate to study this critical region, while with continuous 12 GeV beams one can cleanly access the entire ''valence quark region'' and exploit the newly discovered Generalized Parton Distributions. In addition, a 12-GeV Jefferson Lab can essentially complete the studies of the transition from hadronic to quark-gluon degrees of freedom. (2) It allows crossing the threshold above which the origins of quark confinement can be investigated. Specifically, 12 GeV will enable the production of certain ''exotic'' mesons. Whereas in the QCD region of asymptotic freedom ample evidence for the role of gluons exist through the observation of gluon jets

Study of single Z-boson production and Compton scattering in electron-positron collisions at LEP at centre-of-mass energies up to 209 GeV

CERN Document Server

Vasquez Sierra, Ricardo

2006-01-01

This thesis discusses two main topics. First, the cross section of the process e + e - [arrow right]Ze + e - is measured with 0.7 ph - of data collected with the L3 detector at LEP. Decays of the Z boson into quarks and muons are considered at center-of-mass energies ranging frond 183 GeV up to 209 GeV. The measurements are found to agree with Standard Model predictions, achieving a precision of about 10% for the hadronic channel. Second, Compton scattering of quasi-real virtual photons, γe ± [arrow right]γe ± , is studied with 0.6 fb - 1 of data collected by the L3 detector at LEP at center-of-mass energies [Special characters omitted.] = 189--209GeV. About 4500 events produced by the interaction of virtual photons emitted by particles of one beam with particles of the opposite beam are collected for effective center-of-mass energies of photon-electron and photon-positron systems in the range [Special characters omitted.] = 35 GeV up to [Special characters omitted.] = 175 GeV, the highest energy at which...

Measurement of the Z-boson using $e^+ e^- \\to Z \\gamma$ events at centre-of-mass energies above the Z pole

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, Gerjan J; Böhm, A; Boldizsar, L; Borgia, B; Bottai, S; Bourilkov, D; Bourquin, Maurice; 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 M; 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, Luisa; Cindolo, F; Clare, I; Clare, R; Coignet, G; Colino, N; Costantini, S; de la Cruz, B; Cucciarelli, S; van Dalen, J A; De Asmundis, R; Déglon, P L; 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, D; 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 S; Fiandrini, E; Field, J H; Filthaut, F; Fisher, P H; Fisher, W; Fisk, I; Forconi, G; Freudenreich, Klaus; 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; Guida, M; van Gulik, R; 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; Hu, Y; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Käfer, D; Kaur, M; Kienzle-Focacci, M N; Kim, J K; Kirkby, Jasper; Kittel, E W; Klimentov, A; König, A C; Kopal, M; Koutsenko, V F; Kräber, M H; 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 M; 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 Wen Gan; 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; Musicar, B; Musy, M; Nagy, S; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Nisati, A; Novák, T; Nowak, H; Ofierzynski, R A; Organtini, G; Pal, I; Palomares, C; Paolucci, P; Paramatti, R; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pioppi, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Pothier, J; Prokofev, D; Prokofiev, D O; Quartieri, J; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A V; Razis, P A; Ren, D; Rescigno, M; Reucroft, S; Riemann, S; Riles, K; Roe, B P; Romero, L; Rosca, A; Rosier-Lees, S; Roth, S; Rosenbleck, C; 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 V; 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, Ludwig; 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; Vásquez, R; Veszpremi, V; Vesztergombi, G; Vetlitskii, I; Vicinanza, D; Viertel, Gert M; Villa, S; Vivargent, M; Vlachos, S; Vodopyanov, I; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Wadhwa, M; Wang, Q; Wang, X L; Wang, Z M; Weber, M; Wienemann, P; Wilkens, H; 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

2004-01-01

Events from the e+e- -> Zgamma process with hard initial state radiation collected with the L3 detector at centre-of-mass energies between 183 GeV and 209 GeV are used to measure the mass of the Z boson. Decays of the Z boson into hadrons or muon pairs are considered and the Z mass is determined to be 91.272 +- 0.032 (stat.) +- 0.033 (syst.) GeV, in agreement with the value measured at the Z resonance. Alternatively, assuming this measured value of the Z mass, the method determines the LEP beam energy, found to be 87 +- 34 (stat.) \\pm 34 (syst.) MeV lower than the nominal value.

New newtron time-of-flight (NTOF) facilities at the Brookhaven 200-MeV Linac

International Nuclear Information System (INIS)

Ward, T.E.; Alessi, J.; Brennan, J.; Grand, P.; Lankshear, R.; Snead, C.L.; Tsoupas, N.; Zucker, M.

1988-01-01

The installation of a new beam chopper and radio-frequency quadrupole (RFQ) preinjector (750 keV) at the Brookhaven National Laboratory (BNL) 200-MeV Linac will enable single micropulse selection (pulse width 9 pμ pulse with dc-average beam currents of 50 nA-1 μA routinely available. The NTOF facilities consists of 30-100 meter flight paths at angles of 0, 12, 30, 45, 90, and 135/degree/. Lower energies of 93, 117, 139, 161, and 181 MeV are also available as well as polarized beams at much reduced intensities. The present paper describes the new facilities, and the capabilities of future improvements and upgrades, for use in the BNL intermediate energy (p,n) experimental program. 7 refs., 2 figs., 1 tab

The Efficiency of the BC-720 Scintillator in a High-Energy (20--800 MeV) Accelerator Neutron Field

Energy Technology Data Exchange (ETDEWEB)

Miles, Leslie H. [Univ. of Missouri, Columbia, MO (United States)

2005-12-01

High-energy neutron doses (>20 MeV) are of little importance to most radiation workers. However, space and flight crews, and people working around medical and scientific accelerators receive over half of their radiation dose from high-energy neutrons. Unfortunately, neutrons are difficult to measure, and no suitable dosimetry has yet been developed to measure this radiation. In this paper, basic high-energy neutron interactions, characteristics of high-energy neutron environments, present neutron dosimetry, and quantities used in neutron dosimetry are discussed before looking into the potential of the BC-720 scintillator to improve dosimetry. This research utilized 800 MeV protons impinging upon the WNR Facility spallation neutron source at Los Alamos National Laboratory. Time-of-flight methods and a U-238 Fission Chamber were used to aid evaluation of the efficiency of the BC-720. Results showed that the efficiency is finite over the 20–650 MeV energy region studied, although it decreases by a factor of ten between 40 and 100 MeV. This limits the use of this dosimeter to measure doses at sitespecific locations. It also encourages modifications to use this dosimeter for any unknown neutron field. As such, this dosimeter has the potential for a small, lightweight, real-time dose measurement, which could impact neutron dosimetry in all high-energy neutron environments.

Measurement of Triple Gauge-Boson Couplings at LEP energies up to 189 GeV

CERN Document Server

Heister, A.; Barate, R.; De Bonis, I.; Decamp, D.; Ghez, Philippe; Goy, C.; Jezequel, S.; Lees, J.P.; Martin, F.; Merle, E.; Minard, M.N.; Pietrzyk, B.; Trocme, B.; Bravo, S.; Casado, M.P.; Chmeissani, M.; Crespo, J.M.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, L.; Grauges, E.; Lopez, J.; Martinez, M.; Merino, G.; Miquel, R.; Mir, L.M.; Pacheco, A.; Paneque, D.; Ruiz, H.; Colaleo, A.; Creanza, D.; De Filippis, N.; de Palma, M.; Iaselli, G.; Maggi, G.; Maggi, M.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Azzurri, P.; Barklow, T.; Boix, G.; Buchmuller, O.; Cattaneo, M.; Cerutti, F.; Clerbaux, B.; Dissertori, G.; Drevermann, H.; Forty, R.W.; Frank, M.; Gianotti, F.; Greening, T.C.; Hansen, J.B.; Harvey, John; Hutchcroft, D.E.; Janot, P.; Jost, B.; Kado, M.; Lemaitre, V.; Maley, P.; Mato, P.; Moutoussi, A.; Ranjard, F.; Rolandi, Gigi; Schlatter, D.; Spagnolo, P.; Tejessy, W.; Teubert, F.; Tournefier, E.; Valassi, A.; Ward, J.J.; Wright, A.E.; Ajaltouni, Z.; Badaud, F.; Dessagne, S.; Falvard, A.; Fayolle, D.; Gay, P.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.C.; Pallin, D.; Pascolo, J.M.; Perret, P.; Podlyski, F.; Hansen, J.D.; Hansen, J.R.; Hansen, P.H.; Nilsson, B.S.; Waananen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Vayaki, A.; Blondel, A.; Brient, J.C.; Machefert, F.; Rouge, A.; Swynghedauw, M.; Tanaka, R.; Videau, H.; Focardi, E.; Parrini, G.; Zachariadou, K.; Antonelli, A.; Antonelli, M.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Chiarella, V.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G.P.; Passalacqua, L.; Pepe-Altarelli, M.; Chalmers, M.; Halley, A.W.; Kennedy, J.; Lynch, J.G.; Negus, P.; O'Shea, V.; Raeven, B.; Smith, D.; Thompson, A.S.; Wasserbaech, S.; Cavanaugh, R.; Dhamotharan, S.; Geweniger, C.; Hanke, P.; Hepp, V.; Kluge, E.E.; Leibenguth, G.; Putzer, A.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D.M.; Cameron, W.; Davies, G.; Dornan, P.J.; Girone, M.; Marinelli, N.; Nowell, J.; Przysiezniak, H.; Rutherford, S.; Sedgbeer, J.K.; Thompson, J.C.; White, R.; Ghete, V.M.; Girtler, P.; Kneringer, E.; Kuhn, D.; Rudolph, G.; Bouhova-Thacker, E.; Bowdery, C.K.; Clarke, D.P.; Ellis, G.; Finch, A.J.; Foster, F.; Hughes, G.; Jones, R.W.L.; Pearson, M.R.; Robertson, N.A.; Smizanska, M.; Giehl, I.; Holldorfer, F.; Jakobs, K.; Kleinknecht, K.; Krocker, M.; Muller, A.S.; Nurnberger, H.A.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.G.; Schmeling, S.; Wachsmuth, H.; Zeitnitz, C.; Ziegler, T.; Bonissent, A.; Carr, J.; Coyle, P.; Curtil, C.; Ealet, A.; Fouchez, D.; Leroy, O.; Kachelhoffer, T.; Payre, P.; Rousseau, D.; Tilquin, A.; Aleppo, M.; Gilardoni, Simone S.; Ragusa, F.; David, A.; Dietl, H.; Ganis, G.; Huttmann, K.; Lutjens, G.; Mannert, C.; Manner, W.; Moser, H.G.; Settles, R.; Stenzel, H.; Wolf, G.; Boucrot, J.; Callot, O.; Davier, M.; Duflot, L.; Grivaz, J.F.; Heusse, P.; Jacholkowska, A.; Serin, L.; Veillet, J.J.; Videau, I.; de Vivie de Regie, J.B.; Yuan, C.; Bagliesi, Giuseppe; Boccali, T.; Calderini, G.; Ciulli, V.; Foa, L.; Giammanco, A.; Giassi, A.; Ligabue, F.; Messineo, A.; Palla, F.; Sanguinetti, G.; Sciaba, A.; Sguazzoni, G.; Tenchini, R.; Venturi, A.; Verdini, P.G.; Awunor, O.; Blair, G.A.; Coles, J.; Cowan, G.; Garcia-Bellido, A.; Green, M.G.; Jones, L.T.; Medcalf, T.; Misiejuk, A.; Strong, J.A.; Teixeira-Dias, P.; Clifft, R.W.; Edgecock, T.R.; Norton, P.R.; Tomalin, I.R.; Bloch-Devaux, Brigitte; Boumediene, D.; Colas, P.; Fabbro, B.; Lancon, E.; Lemaire, M.C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.F.; Rosowsky, A.; Seager, P.; Trabelsi, A.; Tuchming, B.; Vallage, B.; Konstantinidis, N.; Litke, A.M.; Loomis, C.; Taylor, G.; Booth, C.N.; Cartwright, S.; Combley, F.; Hodgson, P.N.; Lehto, M.; Thompson, L.F.; Affholderbach, K.; Boehrer, Armin; Brandt, S.; Grupen, C.; Hess, J.; Ngac, A.; Prange, G.; Sieler, U.; Borean, C.; Giannini, G.; He, H.; Putz, J.; Rothberg, J.; Armstrong, S.R.; Cranmer, K.; Elmer, P.; Ferguson, D.P.S.; Gao, Y.; Gonzalez, S.; Hayes, O.J.; Hu, H.; Jin, S.; Kile, J.; McNamara, P.A., III; Nielsen, J.; Orejudos, W.; Pan, Y.B.; Saadi, Y.; Scott, I.J.; von Wimmersperg Toeller, J.H.; Walsh, J.; Wiedenmann, W.; Wu, J.; Wu, Sau Lan; Wu, X.; Zobernig, G.

2001-01-01

The triple gauge-boson couplings involving the W are determined using data samples collected with the ALEPH detector at mean centre-of-mass energies of 183 GeV and 189 GeV, corresponding to integrated luminosities of 57 pb^-1 and 174 pb^-1, respectively. The couplings, g^Z_1, Kappa_gamma and lambda_gamma, are measured using W-pair events, single-W production and single-gamma production. Each coupling is measured individually with the other two coupling fixed at their Standard Model value. Including ALEPH results from lower energies, the 95% confidence level intervals for the deviation to the Standard Model are -0.087 < Dg^Z_1 < 0.141 -0.200 < DKappa_gamma < 0.258 -0.062 < Lambda_gamma < 0.147. Fits are also presented where two or all three couplings are allowed to vary. In addition, W-pair events are used to set limits on the C- or P-violating couplings g^V_4, g^V_5, Kappa~_V, and Lambda~_V, where V denotes either gamma or Z. No deviations from the Standard Model expectations are observed.

High-Energy Emission from Rotation-Powered Pulsars

Science.gov (United States)

Harding, Alice K.

2007-01-01

Thirty-five years after the discovery of rotation-powered pulsars, we still do not understand their pulsed emission at any wavelength. In the last few years there have been some fundamental developments in acceleration and emission models. I will review both the basic physics of the models as well as the latest developments in understanding the high-energy emission of rotation-powered pulsars. Special and general relativistic effects play important roles in pulsar emission, from inertial frame-dragging near the stellar surface to aberration, time-of-flight and retardation of the magnetic field near the light cylinder. Understanding how these effects determine what we observe at different wavelengths is critical to unraveling the emission physics. Fortunately two new gamma-ray telescopes, AGILE and GLAST, with launches expected this year will detect many new gamma-ray pulsars and test the predictions of these models with unprecedented sensitivity and energy resolution for gamma-rays in the range of 30 MeV to 300 GeV.

Monte Carlo simulation of channeled and random profiles of heavy ions implanted in silicon at high energy (1.2 MeV)

International Nuclear Information System (INIS)

Mazzone, A.M.

1987-01-01

In order to study channeling effects and implants of heavy ions with energy of few MeV in silicon, ion distributions are calculated with a Monte Carlo method for axial [(001) axis], planar, and nominally random directions for As + and P + ions implanted into silicon with energies in the range 100 keV to 2 MeV. The calculation indicates an appreciable channeling at the higher energy only for the (001) axis and the (110) planes. For heavy ions with energy in the MeV range the subsidence of channeling into major channels and the disappearance of minor channels are shown

Electrofission of 239Pu in the energy range 7 endash 12 MeV

International Nuclear Information System (INIS)

Arruda-Neto, J.D.; Yoneama, M.; Dias, J.F.; Garcia, F.; Reigota, M.A.; Likhachev, V.P.; Guzman, F.; Rodriguez, O.; Mesa, J.

1997-01-01

The electrofission cross section of 239 Pu(e,f) is measured between 7 and 12 MeV. The data are analyzed by means of the virtual photon formalism, assuming that E1, E2 (T=0), and M1 transitions are involved. Using known estimates for the E1 and E2 (T=0) fission strengths, it is deduced an M1 fission strength of 19±4μ N 2 concentrated near the fission barrier (between 5.4 and 5.8 MeV). The levels of the 239 Pu transition nucleus are theoretically obtained; a bunch of positive-parity levels shows up between 5.5 and 5.9 MeV, which might well be associated with the deduced M1 strength, since the E2 strength is negligible in this energy interval. copyright 1997 The American Physical Society

ISABELLE: a 200 + 200 GeV colliding beam facility

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