WorldWideScience

Sample records for multi gamma lines

  1. Synchrotron radiation-based quasi-elastic scattering using time-domain interferometry with multi-line gamma rays.

    Science.gov (United States)

    Saito, Makina; Masuda, Ryo; Yoda, Yoshitaka; Seto, Makoto

    2017-10-02

    We developed a multi-line time-domain interferometry (TDI) system using 14.4 keV Mössbauer gamma rays with natural energy widths of 4.66 neV from 57 Fe nuclei excited using synchrotron radiation. Electron density fluctuations can be detected at unique lengths ranging from 0.1 nm to a few nm on time scales from several nanoseconds to the sub-microsecond order by quasi-elastic gamma-ray scattering (QGS) experiments using multi-line TDI. In this report, we generalize the established expression for a time spectrum measured using an identical single-line gamma-ray emitter pair to the case of a nonidentical pair of multi-line gamma-ray emitters by considering the finite energy width of the incident synchrotron radiation. The expression obtained illustrates the unique characteristics of multi-line TDI systems, where the finite incident energy width and use of a nonidentical emitter pair produces further information on faster sub-picosecond-scale dynamics in addition to the nanosecond dynamics; this was demonstrated experimentally. A normalized intermediate scattering function was extracted from the spectrum and its relaxation form was determined for a relaxation time of the order of 1 μs, even for relatively large momentum transfer of ~31 nm -1 . The multi-line TDI method produces a microscopic relaxation picture more rapidly and accurately than conventional single-line TDI.

  2. Multi Elemental Study Using Prompt Gamma Technique

    International Nuclear Information System (INIS)

    Normanshah Dahing; Muhamad Samudi Yasir; Normanshah Dahing; Hanafi Ithnin; Mohd Fitri Abdul Rahman; Hearie Hassan

    2016-01-01

    In this study, principle of prompt gamma neutron activation analysis has been used as a technique to determine the elements in the sample. The system consists of collimated isotopic neutron source, Cf-252 with HPGe detector and Multichannel Analysis (MCA). Concrete with size of 10x10x10 cm 3 and 15x15x15 cm 3 were analysed as sample. When neutrons enter and interact with elements in the concrete, the neutron capture reaction will occur and produce characteristic prompt gamma ray of the elements. The preliminary result of this study demonstrate the major element in the concrete was determined such as Si, Mg, Ca, Al, Fe and H as well as others element, such as Cl by analysis the gamma ray lines respectively. The results obtained were compared with computer simulation, NAA and XRF as a part of reference and validation. The potential and the capability of neutron induced prompt gamma as tool for multi elemental analysis qualitatively to identify the elements present in the concrete sample discussed. (author)

  3. About cosmic gamma ray lines

    Science.gov (United States)

    Diehl, Roland

    2017-06-01

    Gamma ray lines from cosmic sources convey the action of nuclear reactions in cosmic sites and their impacts on astrophysical objects. Gamma rays at characteristic energies result from nuclear transitions following radioactive decays or high-energy collisions with excitation of nuclei. The gamma-ray line from the annihilation of positrons at 511 keV falls into the same energy window, although of different origin. We present here the concepts of cosmic gamma ray spectrometry and the corresponding instruments and missions, followed by a discussion of recent results and the challenges and open issues for the future. Among the lessons learned are the diffuse radioactive afterglow of massive-star nucleosynthesis in 26Al and 60Fe gamma rays, which is now being exploited towards the cycle of matter driven by massive stars and their supernovae; large interstellar cavities and superbubbles have been recognised to be of key importance here. Also, constraints on the complex processes making stars explode as either thermonuclear or core-collapse supernovae are being illuminated by gamma-ray lines, in this case from shortlived radioactivities from 56Ni and 44Ti decays. In particular, the three-dimensionality and asphericities that have recently been recognised as important are enlightened in different ways through such gamma-ray line spectroscopy. Finally, the distribution of positron annihilation gamma ray emission with its puzzling bulge-dominated intensity disctribution is measured through spatially-resolved spectra, which indicate that annihilation conditions may differ in different parts of our Galaxy. But it is now understood that a variety of sources may feed positrons into the interstellar medium, and their characteristics largely get lost during slowing down and propagation of positrons before annihilation; a recent microquasar flare was caught as an opportunity to see positrons annihilate at a source.

  4. Gamma ray lines from a universal extra dimension

    Energy Technology Data Exchange (ETDEWEB)

    Bertone, Gianfranco; Jackson, C. B.; Shaughnessy, Gabe; Tait, Tim M.P.; Vallinotto, Alberto

    2012-03-01

    Indirect Dark Matter searches are based on the observation of secondary particles produced by the annihilation or decay of Dark Matter. Among them, gamma-rays are perhaps the most promising messengers, as they do not suffer deflection or absorption on Galactic scales, so their observation would directly reveal the position and the energy spectrum of the emitting source. Here, we study the detailed gamma-ray energy spectrum of Kaluza--Klein Dark Matter in a theory with 5 Universal Extra Dimensions. We focus in particular on the two body annihilation of Dark Matter particles into a photon and another particle, which produces monochromatic photons, resulting in a line in the energy spectrum of gamma rays. Previous calculations in the context of the five dimensional UED model have computed the line signal from annihilations into \\gamma \\gamma, but we extend these results to include \\gamma Z and \\gamma H final states. We find that these spectral lines are subdominant compared to the predicted \\gamma \\gamma signal, but they would be important as follow-up signals in the event of the observation of the \\gamma \\gamma line, in order to distinguish the 5d UED model from other theoretical scenarios.

  5. Multiple gamma lines from semi-annihilation

    International Nuclear Information System (INIS)

    D'Eramo, Francesco; McCullough, Matthew; Thaler, Jesse

    2013-01-01

    Hints in the Fermi data for a 130 GeV gamma line from the galactic center have ignited interest in potential gamma line signatures of dark matter. Explanations of this line based on dark matter annihilation face a parametric tension since they often rely on large enhancements of loop-suppressed cross sections. In this paper, we pursue an alternative possibility that dark matter gamma lines could arise from ''semi-annihilation'' among multiple dark sector states. The semi-annihilation reaction ψ i ψ j → ψ k γ with a single final state photon is typically enhanced relative to ordinary annihilation ψ i ψ-bar i → γγ into photon pairs. Semi-annihilation allows for a wide range of dark matter masses compared to the fixed mass value required by annihilation, opening the possibility to explain potential dark matter signatures at higher energies. The most striking prediction of semi-annihilation is the presence of multiple gamma lines, with as many as order N 3 lines possible for N dark sector states, allowing for dark sector spectroscopy. A smoking gun signature arises in the simplest case of degenerate dark matter, where a strong semi-annihilation line at 130 GeV would be accompanied by a weaker annihilation line at 173 GeV. As a proof of principle, we construct two explicit models of dark matter semi-annihilation, one based on non-Abelian vector dark matter and the other based on retrofitting Rayleigh dark matter

  6. JADSPE, Multi-Channel Gamma Spectra Unfolding Program

    International Nuclear Information System (INIS)

    Rikovska, J.; Stejskalova, E.

    2005-01-01

    1 - Description of program or function: JADSPE is a package of eight programs to process multi-channel gamma-ray spectra. The programs can be used to: - locate automatically spectral peaks and calculate their positions, areas, and full widths at half maximum (FWHM); - plot the spectra on a CALCOMP plotter, TEKTRONIX terminal or a line printer; - add or subtract several spectra with the possibility of adjusting either their start and end channels or the maxima of the chosen corresponding peaks. The JADSPE package comprises the following programs: - SPECTF: automatic location of peaks and calculation of their positions, areas and FWHMS. The standard deviations of peak parameters are also determined, and each evaluated region is plotted on the line printer. - SPECT1: The areas and FWHMs are calculated for peaks whose positions are known beforehand. The standard deviations of calculated parameters are also determined, and each evaluated region is plotted on the line printer. - PLOCHA: The peak net area is calculated by summing the channel contents in specified regions and by subtracting a linear background. - GRAPH: Spectrum plotting on the line printer. - PLTNEW: Spectrum plotting on CALCOMP plotter or on TEKTRONIX terminal. - SUMDIF: The channel contents of several gamma-ray spectra are added or subtracted. - SSPFP: The channel contents of several gamma-ray spectra are added with adjustment of the maxima of specified peaks. - SOUCET: The channel contents of several gamma-ray spectra are added with the adjustment of start and end channels of the spectra. 2 - Method of solution: Non-linear least-square fit. 3 - Restrictions on the complexity of the problem: The full energy peaks are approximated by a symmetrical Gaussian function and the underlying background is approximated by a first-order polynomial. A fixed spectrum length of 4096 channels is assumed. Maxima of: - number of peaks in one multiplet: 9; - number of peaks identified by the automatic search procedure

  7. True coincidence summing correction determination for 214Bi principal gamma lines in NORM samples

    International Nuclear Information System (INIS)

    Haddad, Kh.

    2014-01-01

    The gamma lines 609.3 and 1,120.3 keV are two of the most intensive γ emissions of 214 Bi, but they have serious true coincidence summing (TCS) effects due to the complex decay schemes with multi-cascading transitions. TCS effects cause inaccurate count rate and hence erroneous results. A simple and easy experimental method for determination of TCS correction of 214 Bi gamma lines was developed in this work using naturally occurring radioactive material samples. Height efficiency and self attenuation corrections were determined as well. The developed method has been formulated theoretically and validated experimentally. The corrections problems were solved simply with neither additional standard source nor simulation skills. (author)

  8. Significant gamma-ray lines from dark matter annihilation

    Energy Technology Data Exchange (ETDEWEB)

    Duerr, Michael [DESY, Notkestrasse 85, 22607 Hamburg (Germany); Fileviez Perez, Pavel; Smirnov, Juri [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany)

    2016-07-01

    Gamma-ray lines from dark matter annihilation are commonly seen as a ''smoking gun'' for the particle nature of dark matter. However, in many dark matter models the continuum background from tree-level annihilations makes such a line invisible. I present two simple extensions of the Standard Model where the continuum contributions are suppressed and the gamma-ray lines are easily visible over the continuum background.

  9. Gamma and beta logging of underground sewer and process lines

    International Nuclear Information System (INIS)

    Rangel, M.J.; Martz, D.E.; Langner, G.H. Jr.

    1989-11-01

    The GammaSnake can be useful for locating uranium mill tailings used as backfill for sewer lines or storm drains where the lines can be readily accessed from a cleanout access port or other opening. The time required to determine if contamination is present using the GammaSnake method is considerably less than when using the delta gamma or drilling methods. There is, also, less potential hazard to the equipment operators when using the GammaSnake method. The GammaSnake method is generally limited to a distance of 100 feet or less. Used with the MAC-51B line locator, the GammaSnake method can provide useful information without extensive drilling or surveying. 7 figs., 2 tabs

  10. Gamma-ray line intensities for depleted uranium

    International Nuclear Information System (INIS)

    Moss, C.E.

    1985-01-01

    Measurements of the gamma-ray line intensities from depleted uranium allowed us to determine which of two conflicting previous experiments was correct. For the 1001-keV line we obtain a branching ratio of 0.834 +- 0.007, in good agreement with one of the previous experiments. A table compares our intensities for several lines with those obtained in previous experiments. 5 refs., 2 figs., 1 tab

  11. Nuclear gamma ray lines from supernovae

    International Nuclear Information System (INIS)

    Jardim, J.O.D.

    1980-01-01

    From theoretical considerations of the behaviour of gamma ray line fluxes occurring after a supernova explosion, the 1.156 and 0.847 MeV lines are seen to be the most likely to be observed. The 1.156 MeV line has been previously observed by other investigators. Observations of the 0.847 MeV line, and 1.332, 1.173 and 0.059 MeV lines using a Ge(Li) telescope aboard a stratospheric balloon which was flown in Brazil in 1977 are reported. The observation using a NaI(Tl) detector of a line in the energy interval 1.5 - 1.6 MeV, which may be due to 0 18 (p,p') 0 18 sup (*) reaction is also reported. (Author) [pt

  12. SN 1987A gamma-ray line profiles and fluxes

    International Nuclear Information System (INIS)

    Bussard, R.W.; Burrows, A.; The, L.S.

    1989-01-01

    Results for the time dependence of the line profiles and integrated fluxes for the 0.847 and 1.238 MeV gamma rays from the decay of cobalt to excited states of iron are presented for several models of the ejectum of SN 1987A. The relatively early detection of these lines has led several workers to propose that some degree of mixing has brought the cobalt closer to the electron-scattering photosphere than standard models predict. Constraints on the amount of mixing from recent observations are discussed using calculations of the energy-integrated line fluxes as a function of time since the explosion. Implications for the line profiles at various times are considered, and it is found that they show strong time dependences and are quite sensitive to the degree of mixing. The two primary effects are Doppler broadening due to the presence of radioactive material at higher velocities and a strong blueshift at early times resulting from optical depth effects. These results have important implications for gamma-ray observations, especially with high-resolution germanium instruments. Finally, the consequences of the fragmentation of the debris for the early emergence of the gamma-ray lines are considered. 32 refs

  13. Computer program SCAP-BR for gamma-ray streaming through multi-legged ducts

    International Nuclear Information System (INIS)

    Byoun, T.Y.; Babel, P.J.; Dajani, A.T.

    1977-01-01

    A computer program, SCAP-BR, has been developed at Burns and Roe for the gamma-ray streaming analysis through multi-legged ducts. SCAP-BR is a modified version of the single scattering code, SCAP, incorporating capabilities of handling multiple scattering and volumetric source geometries. It utilizes the point kernel integration method to calculate both the line-of-sight and scattered gamma dose rates by employing the ray tracing technique through complex shield geometries. The multiple scattering is handled by a repeated process of the single scatter method through each successive scatter region and collapsed pseudo source meshes constructed on the relative coordinate systems. The SCAP-BR results have been compared with experimental data for a Z-type (three-legged) concrete duct with a Co-60 source placed at the duct entrance point. The SCAP-BR dose rate predictions along the duct axis demonstrate an excellent agreement with the measured values

  14. A search for spectral lines in gamma-ray bursts using TGRS

    International Nuclear Information System (INIS)

    Kurczynski, P.; Palmer, D.; Seifert, H.; Teegarden, B. J.; Gehrels, N.; Cline, T. L.; Ramaty, R.; Hurley, K.; Madden, N. W.; Pehl, R. H.

    1998-01-01

    We present the results of an ongoing search for narrow spectral lines in gamma-ray burst data. TGRS, the Transient Gamma-Ray Spectrometer aboard the Wind satellite is a high energy-resolution Ge device. Thus it is uniquely situated among the array of space-based, burst sensitive instruments to look for line features in gamma-ray burst spectra. Our search strategy adopts a two tiered approach. An automated 'quick look' scan searches spectra for statistically significant deviations from the continuum. We analyzed all possible time accumulations of spectra as well as individual spectra for each burst. Follow-up analysis of potential line candidates uses model fitting with F-test and χ 2 tests for statistical significance

  15. Line and continuum spectroscopy as diagnostic tools for gamma ray bursts

    International Nuclear Information System (INIS)

    Liang, E.P.

    1990-12-01

    We review the theoretical framework of both line and continuum spectra formation in gamma ray bursts. These include the cyclotron features at 10's of keV, redshifted annihilation features at ∼400 keV, as well as other potentially detectable nuclear transition lines, atomic x-ray lines, proton cyclotron lines and plasma oscillation lines. By combining the parameters derived from line and continuum modeling we can try to reconstruct the location, geometry and physical conditions of the burst emission region, thereby constraining and discriminating the astrophysical models. Hence spectroscopy with current and future generations of detectors should provide powerful diagnostic tools for gamma ray bursters. 48 refs., 10 figs., 4 tabs

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

  17. Gamma-ray lines from radiative dark matter decay

    International Nuclear Information System (INIS)

    Garny, Mathias; Ibarra, Alejandro; Tran, David; Weniger, Christoph

    2011-01-01

    The decay of dark matter particles which are coupled predominantly to charged leptons has been proposed as a possible origin of excess high-energy positrons and electrons observed by cosmic-ray telescopes PAMELA and Fermi LAT. Even though the dark matter itself is electrically neutral, the tree-level decay of dark matter into charged lepton pairs will generically induce radiative two-body decays of dark matter at the quantum level. Using an effective theory of leptophilic dark matter decay, we calculate the rates of radiative two-body decays for scalar and fermionic dark matter particles. Due to the absence of astrophysical sources of monochromatic gamma rays, the observation of a line in the diffuse gamma-ray spectrum would constitute a strong indication of a particle physics origin of these photons. We estimate the intensity of the gamma-ray line that may be present in the energy range of a few TeV if the dark matter decay interpretation of the leptonic cosmic-ray anomalies is correct and comment on observational prospects of present and future Imaging Cherenkov Telescopes, in particular the CTA

  18. Ras p21 and other Gn proteins are detected in mammalian cell lines by [gamma-35S]GTP gamma S binding

    International Nuclear Information System (INIS)

    Comerford, J.G.; Gibson, J.R.; Dawson, A.P.; Gibson, I.

    1989-01-01

    The presence of guanine nucleotide binding proteins in mouse and human cell lines was investigated using [gamma- 35 S]GTP gamma S and [gamma-32P]GTP. Cell lysate polypeptides were separated by sodium dodecyl sulphate polyacrylamide gel electrophoresis and transferred to nitrocellulose. Incubation of the nitrocellulose blots with [gamma- 35 S]GTP gamma S identified 9 distinct GTP-binding polypeptides in all lysates. One of these is the ras oncogene product, p21, as demonstrated by subsequent immunochemical staining of the nitrocellulose blots. We have shown that this procedure provides a sensitive method for detection of p21 in culture cell lines

  19. Clustering of galaxies around gamma-ray burst sight-lines

    DEFF Research Database (Denmark)

    Sudilovsky, V.; Greiner, J.; Rau, A.

    2013-01-01

    -lines, as strong MgII tends to trace these sources. In this work, we test this expectation by calculating the two point angular correlation function of galaxies within 120'' (~470 h Kpc470h71-1Kpc at z ~ 0.4) of GRB afterglows. We compare the gamma-ray burst optical and near-infrared detector (GROND) GRB afterglow.......3. This result is contrary to the expectations from the MgII excess derived from GRB afterglow spectroscopy, although many confirmed galaxy counterparts to MgII absorbers may be too faint to detect in our sample-especially those at z > 1. We note that the addition of higher sensitivity Spitzer/IRAC or HST/WFC3......There is evidence of an overdensity of strong intervening MgII absorption line systems distributed along the lines of sight toward gamma-ray burst (GRB) afterglows relative to quasar sight-lines. If this excess is real, one should also expect an overdensity of field galaxies around GRB sight...

  20. Observation of solar gamma-ray by Hinotori

    International Nuclear Information System (INIS)

    Yoshimori, Masato; Okudaira, Kiyoaki; Hirashima, Yo; Kondo, Ichiro.

    1982-01-01

    The solar gamma-ray emitted by solar flare was observed. The gamma-ray is the electromagnetic radiation with the energy more than 300 keV. The line gamma-ray intensity and the time profile were observed. The gamma-ray detector CsI (Tl) was loaded on Hinotori, and the observed gamma-ray was analyzed by a multi-channel analyzer. The observed line gamma-ray was the radiation from Fe-56 and Ne-20. The line gamma-ray from C-12 and O-16 was also seen. These gamma-ray is the direct evidence of the nuclear reaction on the sun. The observed spectrum suggested the existence of the lines from Mg-24 and Si-28. The intensity of the 2.22 MeV gamma-line was small. This fact showed that the origin of this line was different from other nuclear gamma-ray. Two kinds of hard X-ray bursts were detected. The one was impulsive burst, and the other was gradual burst. There was no time difference between the hard X-ray and the gamma-ray of the impulsive burst. The impulsive burst may be explained by the beam model. The delay of time profile in the high energy gamma-ray of the gradual burst was observed. This means that the time when accelerated electrons cause bremsstrahlung depends on the electron energy. The long trapping of electrons at the top of magnetic loop is suggested. (Kato, T.)

  1. Université de Genève : Gamma-ray lines astronomy

    CERN Multimedia

    2006-01-01

    Ecole de physique Département de physique nucléaire et corspusculaire 24, Quai Ernest-Ansermet 1211 Genève 4 Tél. : (022) 379 62 73 Fax: (022) 379 69 92 Wednesday 8 March PARTICLE PHYSICS SEMINAR at 17:00 - Stückelberg Auditorium Gamma-ray lines astronomy by Prof. Nicolas Prantzos / CNRS, Paris Gamma-ray lines from cosmic sources provide unique isotopic information, since they originate from energy level transitions in the atomic nucleus. Gamma-ray telescopes explored this astronomical window in the past three decades, detecting radioactive isotopes that have been ejected in interstellar space by cosmic nucleosynthesis events. Astronomical gamma-ray telescopes feature standard detectors of nuclear physics, but have to be surrounded by effective shields against local instrumental background, and need special detector and/or mask arrangements to collect imaging information. Due to exceptionally-low signal/noise ratios, progress in the field has been slow compared with other wavelengths. Despite the...

  2. Gamma-ray imaging spectrometer (GRIS): a new balloon-borne experiment for gamma-ray line astronomy

    International Nuclear Information System (INIS)

    Teegarden, B.J.; Cline, T.L.; Gehrels, N.; Porreca, G.; Tueller, J.; Leventhal, M.; Huters, A.F.; MacCallum, C.J.; Stang, P.D.

    1985-01-01

    High resolution gamma-ray spectroscopy is a relatively new field that holds great promise for further understanding of high energy astrophysical processes. Preliminary results such as the annihilation radiation from the galactic center, the 26 Al line from the galactic plane and cyclotron lines from neutron stars may well be just the initial discoveries of a rich and as yet undeveloped field. When the high resolution gamma-ray spectrometer (GRSE) was removed from the GRO payload NASA decided to initiate a balloon program to permit continued development and improvement of instrumentation in this field, as well as continued scientific observations. The Gamma-Ray Imaging Spectrometer (GRIS) is one of the experiments selected as part of this program. The instrument contains a number of new and innovative features that are expected to produce a significant improvement in source location accuracy and sensitivity over previous balloon and satellite experiments. 6 refs., 2 figs

  3. Gamma ray induced diversity in restorer line of cotton (Gossypium Hirsutum)

    International Nuclear Information System (INIS)

    Mehetre, S.S.; Patil, V.R.; Surana, P.P.

    2000-01-01

    Looking to the limitation of very few restorers available in cotton a diversification of available restorer line was undertaken by gamma irradiation. The four hundred individual plants selected from individual M 2 families were crossed with CMS lines. Out of which 12 plants restored fertility in CMS lines and their F 1 's with CMS produced more heterotic hybrids than their checks (control). The results indicated that sufficient variability can be induced with the help of gamma rays and the diversification of restorers is possible within a short period with simultaneous improvement in either one or two characters. (author)

  4. Fermi LAT Search for Dark Matter in Gamma-Ray Lines and the Inclusive Photon Spectrum

    Science.gov (United States)

    Ackermann, M.; Ajello, M.; Albert, A.; Baldini, L.; Barbiellini, G.; Bechtol, K.; Bellazzini, R.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; hide

    2012-01-01

    Dark matter particle annihilation or decay can produce monochromatic gamma-ray lines and contribute to the diffuse gamma-ray background. Flux upper limits are presented for gamma-ray spectral lines from 7 to 200 GeV and for the diffuse gamma-ray background from 4.8 GeV to 264 GeV obtained from two years of Fermi Large Area Telescope data integrated over most of the sky. We give cross section upper limits and decay lifetime lower limits for dark matter models that produce gamma-ray lines or contribute to the diffuse spectrum, including models proposed as explanations of the PAMELA and Fermi cosmic-ray data.

  5. Evaluation of artemisia mutant lines conducted from gamma irradiation treatment

    International Nuclear Information System (INIS)

    Ragapadmi Purnamaningsih; EG Lestari; M Syukur

    2010-01-01

    Cases of Malaria diseases attack in Indonesia has been increasing. Plasmodium falciparum the cause of malaria disease is now resistant to the usual medicine. One of malaria medicine which recommended by WHO is artemisinine compound extracted from Artemisia annua L plant. Low artemisinine content is one problem of Artemisia development in Indonesia. Increasing genetic variation using gamma irradiation is one alternative method to improve artemisinin content. In 2007, induce mutation had been done to artemisia seeds using gamma irradiation at dosage of 10-100 Gy. The good rooting planlet was regenerated and acclimatized in the green house, and then the seedling (M0 generation) was planted in the field at 1545 m asl. Plants derived from seeds without gamma irradiation treatment and cultured in vitro (in vitro control) were used as control. The result showed there were some morphological variations between the mutant lines (plant height, shape of the leaves and time of flowering). Ten mutant lines were selected based on biomass yield and analyzed for the artemisinine content.The result showed that artemisinine content of the mutant lines ranged from 0.44 - 1.41%, and it was significantly higher than that of in vitro control (0.43%). (author)

  6. Non destructive multi elemental analysis using prompt gamma neutron activation analysis techniques: Preliminary results for concrete sample

    Energy Technology Data Exchange (ETDEWEB)

    Dahing, Lahasen Normanshah [School of Applied Physics, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia and Malaysian Nuclear Agency (Nuklear Malaysia), Bangi 43000, Kajang (Malaysia); Yahya, Redzuan [School of Applied Physics, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Yahya, Roslan; Hassan, Hearie [Malaysian Nuclear Agency (Nuklear Malaysia), Bangi 43000, Kajang (Malaysia)

    2014-09-03

    In this study, principle of prompt gamma neutron activation analysis has been used as a technique to determine the elements in the sample. The system consists of collimated isotopic neutron source, Cf-252 with HPGe detector and Multichannel Analysis (MCA). Concrete with size of 10×10×10 cm{sup 3} and 15×15×15 cm{sup 3} were analysed as sample. When neutrons enter and interact with elements in the concrete, the neutron capture reaction will occur and produce characteristic prompt gamma ray of the elements. The preliminary result of this study demonstrate the major element in the concrete was determined such as Si, Mg, Ca, Al, Fe and H as well as others element, such as Cl by analysis the gamma ray lines respectively. The results obtained were compared with NAA and XRF techniques as a part of reference and validation. The potential and the capability of neutron induced prompt gamma as tool for multi elemental analysis qualitatively to identify the elements present in the concrete sample discussed.

  7. Evaluation of Multi-Channel ADCs for Gamma-Ray Spectroscopy

    Science.gov (United States)

    Tan, Hui; Hennig, Wolfgang; Walby, Mark D.; Breus, Dimitry; Harris, Jackson

    2013-04-01

    As nuclear physicists increasingly design large scale experiments with hundreds or thousands of detector channels, there are growing needs for high density readout electronics with good timing and energy resolution that at the same time offer lower cost per channel compared to existing commercial solutions. Recent improvements in the design of commercial analog to digital converters (ADCs) have resulted in a variety of multi-channel ADCs that are natural choice for designing such high density readout modules. However, multi-channel ADCs typically are designed for medical imaging/ultrasound applications and therefore are not rated for their spectroscopic characteristics. In this work, we evaluated the gamma-ray spectroscopic performance of several multi-channel ADCs, including their energy resolution, nonlinearity, and timing resolution. Some of these ADCs demonstrated excellent energy resolution, 2.66% FWHM at 662 keV with a LaBr3 or 1.78 keV FWHM at 1332.5 keV with a high purity germanium (HPGe) detector, and sub-nanosecond timing resolution with LaBr 3. We present results from these measurements to illustrate their suitability for gamma-ray spectroscopy.

  8. Gamma-radiography techniques applied to quality control of welds in water pipe lines

    International Nuclear Information System (INIS)

    Sanchez, W.; Oki, H.

    1974-01-01

    Non-destructive testing of welds may be done by the gamma-radiography technique, in order to detect the presence or absence of discontinuities and defects in the bulk of deposited metal and near the base metal. Gamma-radiography allows the documentation of the test with a complete inspection record, which is a fact not common in other non-destructive testing methods. In the quality control of longitudinal or transversal welds in water pipe lines, two exposition techniques are used: double wall and panoramic exposition. Three different water pipe lines systems have analysed for weld defects, giving a total of 16,000 gamma-radiographies. The tests were made according to the criteria established by the ASME standard. The principal metallic discontinuites found in the weld were: porosity (32%), lack of penetration (29%), lack of fusion (20%), and slag inclusion (19%). The percentage of gamma-radiographies showing welds without defects was 39% (6168 gamma-radiographies). On the other hand, 53% (8502 gamma-radiographies) showed the presence of acceptable discontinuities and 8% (1330 gamma-radiographies) were rejected according to the ASME standards [pt

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

    International Nuclear Information System (INIS)

    Bernardes, Estela Maria de Oliveira

    2001-01-01

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

  10. Influence of gamma rays colimation on Mosbauer lines

    International Nuclear Information System (INIS)

    Flores-Llamas, H.; Jimenez-Dominguez, Homero

    1989-01-01

    The effect of gamma rays collimation in Mossbauer absorption spectra was investigated when thin absorbers are used. A simple model is proposed to study shift and broadening of spectral lines. This model along with some approximations, makes the calculations easily done. The results are in good agreement with those in the literature. (author)

  11. On the origin of gamma rays in Fermi blazars: beyond the broad line region.

    Science.gov (United States)

    Costamante, L.; Cutini, S.; Tosti, G.; Antolini, E.; Tramacere, A.

    2018-05-01

    The gamma-ray emission in broad-line blazars is generally explained as inverse Compton (IC) radiation of relativistic electrons in the jet scattering optical-UV photons from the Broad Line Region (BLR), the so-called BLR External Compton scenario. We test this scenario on the Fermi gamma-ray spectra of 106 broad-line blazars detected with the highest significance or largest BLR, by looking for cut-off signatures at high energies compatible with γ-γ interactions with BLR photons. We do not find evidence for the expected BLR absorption. For 2/3 of the sources, we can exclude any significant absorption (τmax 5). We conclude that for 9 out of 10 objects, the jet does not interact with BLR photons. Gamma-rays seem either produced outside the BLR most of the time, or the BLR is ˜100 × larger than given by reverberation mapping. This means that i) External Compton on BLR photons is disfavoured as the main gamma-ray mechanism, vs IC on IR photons from the torus or synchrotron self-Compton; ii) the Fermi gamma-ray spectrum is mostly intrinsic, determined by the interaction of the particle distribution with the seed-photons spectrum; iii) without suppression by the BLR, broad-line blazars can become copious emitters above 100 GeV, as demonstrated by 3C 454.3. We expect the CTA sky to be much richer of broad-line blazars than previously thought.

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

    Science.gov (United States)

    Hobbs, L. M.

    1973-01-01

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

  13. Modeling the Broad-Band Emission from the Gamma-Ray Emitting Narrow-Line Seyfert-1 Galaxies 1H 0323+342 and B2 0954+25A

    International Nuclear Information System (INIS)

    Arrieta-Lobo, Maialen; Boisson, Catherine; Zech, Andreas

    2017-01-01

    Prior to the Fermi-LAT era, only two classes of Active Galactic Nuclei (AGN) were thought to harbor relativistic jets that radiate up to gamma-ray energies: blazars and radio galaxies. The detection of variable gamma-ray emission from Narrow Line Seyfert 1 (NLSy1) galaxies has put them on the spotlight as a new class of gamma-ray emitting AGN. In this respect, gamma-ray emitting NLSy1s seem to be situated between blazars (dominated by non-thermal emission) and Seyferts (accretion disc dominated). In this work, we model the Spectral Energy Distribution (SED) of two gamma-loud NLSy1s, 1H 0323+342 and B2 0954+25A, during quiescent and flaring episodes via a multi-component radiative model that features a relativistic jet and external photon fields from the torus, disc, corona and Broad Line Region (BLR). We find that the interpretation of the high-energy emission of jetted NLSy1s requires taking into account Inverse Compton emission from particles in the relativistic jet that interact with external photon fields. Minimal changes are applied to the model parameters to transition from average to flaring states. In this scenario, the observed variability is explained mainly by means of changes in the jet density and Doppler factor.

  14. Modeling the Broad-Band Emission from the Gamma-Ray Emitting Narrow-Line Seyfert-1 Galaxies 1H 0323+342 and B2 0954+25A

    Energy Technology Data Exchange (ETDEWEB)

    Arrieta-Lobo, Maialen; Boisson, Catherine; Zech, Andreas, E-mail: maialen.arrieta@obspm.fr [Laboratoire Univers et Theories, Observatoire de Paris, CNRS, Université Paris-Diderot, PSL Research University, Meudon (France)

    2017-12-08

    Prior to the Fermi-LAT era, only two classes of Active Galactic Nuclei (AGN) were thought to harbor relativistic jets that radiate up to gamma-ray energies: blazars and radio galaxies. The detection of variable gamma-ray emission from Narrow Line Seyfert 1 (NLSy1) galaxies has put them on the spotlight as a new class of gamma-ray emitting AGN. In this respect, gamma-ray emitting NLSy1s seem to be situated between blazars (dominated by non-thermal emission) and Seyferts (accretion disc dominated). In this work, we model the Spectral Energy Distribution (SED) of two gamma-loud NLSy1s, 1H 0323+342 and B2 0954+25A, during quiescent and flaring episodes via a multi-component radiative model that features a relativistic jet and external photon fields from the torus, disc, corona and Broad Line Region (BLR). We find that the interpretation of the high-energy emission of jetted NLSy1s requires taking into account Inverse Compton emission from particles in the relativistic jet that interact with external photon fields. Minimal changes are applied to the model parameters to transition from average to flaring states. In this scenario, the observed variability is explained mainly by means of changes in the jet density and Doppler factor.

  15. Stability Test For Sorghum Mutant Lines Derived From Induced Mutations with Gamma-Ray Irradiation

    Directory of Open Access Journals (Sweden)

    S. Human

    2011-12-01

    Full Text Available Sorghum breeding program had been conducted at the Center for the Application of Isotopes and Radiation Technology, BATAN. Plant genetic variability was increased through induced mutations using gamma-ray irradiation. Through selection process in successive generations, some promising mutant lines had been identified to have good agronomic characteristics with high grain yield. These breeding lines were tested in multi location trials and information of the genotypic stability was obtained to meet the requirements for officially varietal release by the Ministry of Agriculture. A total of 11 sorghum lines and varieties consisting of 8 mutant lines derived from induced mutations (B-100, B-95, B-92, B-83, B-76, B-75, B-69 and Zh-30 and 3 control varieties (Durra, UPCA-S1 and Mandau were included in the experiment. All materials were grown in 10 agro-ecologically different locations namely Gunungkidul, Bantul, Citayam, Garut, Lampung, Bogor, Anyer, Karawaci, Cianjur and Subang. In each location, the local adaptability test was conducted by randomized block design with 3 replications. Data of grain yield was used for evaluating genotypic stability using AMMI approach. Results revealed that sorghum mutation breeding had generated 3 mutant lines (B-100, B-76 and Zh-30 exhibiting grain yield significantly higher than the control varieties. These mutant lines were genetically stable in all locations so that they would be recommended for official release as new sorghum varieties to the Ministry of Agriculture

  16. Multi-dimensional analysis of high resolution {gamma}-ray data

    Energy Technology Data Exchange (ETDEWEB)

    Flibotte, S.; Huettmeier, U.J.; France, G. de; Haas, B.; Romain, P.; Theisen, Ch.; Vivien, J.P.; Zen, J. [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires

    1992-12-31

    A new generation of high resolution {gamma}-ray spectrometers capable of recording high-fold coincidence events with a large efficiency will soon be available. Algorithms are developed to analyze high-fold {gamma}-ray coincidences. As a contribution to the software development associated with the EUROGAM spectrometer, the performances of computer codes designed to select multi-dimensional gates from 3-, 4- and 5-fold coincidence databases were tested. The tests were performed on events generated with a Monte Carlo simulation and also on real experimental triple data recorded with the 8{pi} spectrometer and with a preliminary version of the EUROGAM array. (R.P.) 14 refs.; 3 figs.; 3 tabs.

  17. Hunting 1-500 GeV dark matter gamma-ray lines with the Fermi LAT

    International Nuclear Information System (INIS)

    Vertongen, Gilles; Weniger, Christoph

    2010-12-01

    Monochromatic photons could be produced in the annihilation or decay of dark matter particles. At high energies, the search for such line features in the cosmic gamma-ray spectrum is essentially background free because plausible astrophysical processes are not expected to produce such a signal. The observation of a gamma-ray line would hence be a 'smoking-gun' signature for dark matter, making the search for such signals particularly attractive. Among the different dark matter models predicting gamma-ray lines, the local supersymmetric extension of the standard model with small R-parity violation and gravitino LSP is of particular interest because it provides a framework where primordial nucleosynthesis, gravitino dark matter and thermal leptogenesis are naturally consistent. Using the two-years Fermi LAT data, we present a dedicated search for gamma-ray lines coming from dark matter annihilation or decay in the Galactic halo. Taking into account the full detector response, and using a binned profile likelihood method, we search for significant line features in the energy spectrum of the diffuse flux observed in different regions of the sky. No evidence for line signals at the 5σ level is found for photon energies between 1 and 500 GeV, and the corresponding bounds on dark matter decay rates and annihilation cross sections are presented. Implications for gravitino dark matter in presence of small R-parity violation are discussed, as well as the impact of our results on the prospect for seeing long-lived neutralinos or staus at the LHC. (orig.)

  18. The allure of multi-line games in modern slot machines.

    Science.gov (United States)

    Dixon, Mike J; Graydon, Candice; Harrigan, Kevin A; Wojtowicz, Lisa; Siu, Vivian; Fugelsang, Jonathan A

    2014-11-01

    In multi-line slot machines, players can wager on more than one line per spin. We sought to show that players preferred multi-line over single-line games, and that certain game features could cause multi-line game play to feel more rewarding. Reward was measured using post-reinforcement pauses (PRPs) following each outcome (the time between outcome delivery and the next spin). Gamblers (n = 102) played 250 spins on a 20-line game and 250 spins on a one-line game (answering questions about game experiences following each session). Playing one-line, a small credit gain (e.g. 2 cents) was a net win. In the 20-line game it was a net loss of 18 credits but was still accompanied by 'winning' sights and sounds. Most players (94%) preferred the 20-line game. PRPs for small credit gains (net losses) in the 20-line game were equivalent, or larger than in the one-line game where such gains were wins. The largest increase in PRP size was between the 0 and 2 credit conditions for both games. Thus 20-line players reacted as though these net losses of 18 credits were rewarding. Players' estimates of the number of true wins were accurate in the one-line game, but they significantly over-estimated the number of true wins in the 20-line game (P game play. Multi-line games appear to be more appealing to gaming machine ('slots') players than single-line games. These games may be particularly absorbing for those with gambling problems. © 2014 Society for the Study of Addiction.

  19. Generation of gamma irradiation and EMS-induced mutant lines of the H7996 tomato (Solanum lycopersicum L.)

    International Nuclear Information System (INIS)

    Canama, Alma O.; Galvez, Hayde F.; Tongson, Eden Jane U.; Quilloy, Reynaldo B.; Hautea, Desiree M.

    2010-01-01

    Tomato (L.) is one of the most important vegetable crops grown worldwide for the fresh vegetable market and food processing industry. With the completion of the genome-sequencing projects in various crops, the major challenge will be determine the gene function. One approach is to generate and to analyze mutant phenotypes. The paper reports the generation of gamma-irradiated and ethy methane sulfonate (EMS)-treated mutant populations, identification and phenotypic characterization of dominant and visible mutations in tomato mutant lines. Mutant populations of tomato H7996 were created using physical (cobalt 60 gamma ray) and chemical EMS mutagens. Generally, based on high-throughput phenotypic characterization, mutations were observed on the plant habit, size, morphology, leaf and flower color and morphology and fruit characteristics. Specifically, the most common dominant and visible mutations noted in the M 1 generation were monopodial, compact, short internodes, multi-branch plant type, light yellow and ghost leaf coloration, tiny and long pedicel leaf morphology and small or short plant size. In the M2 generation, homogeneous and segregating M 2 families were selected to constitute the core set of visible tomato mutants. Initial bacterial wilt resistance (BWR) gene knockouts were also identified. The mutant lines will be used as a rich source of genetic materials for breeding and functional genomics of tomato. (author)

  20. Meiosis in gamma-ray induced tomato mutants of line XXIV-a

    International Nuclear Information System (INIS)

    Zagorcheva, L.; Jordanov, M.

    1976-01-01

    Results are reported of investigations on meiosis in tomato mutants obtained by gamma-irradiation ( 60 Co) of seeds from line XXIV-a with doses of 20 and 30 krad. Two genome mutants (one a triploid and the other a tetraploid form) as well as a chromosome aberration of the translocation type, were selected in the course of the investigations and their meiosis is described. Meiosis in the initial form (line XXIV-a) was also studied. About 16% of the initial line XXIV-a plants proved to be trisomic forms. (author)

  1. Line C17: alpha and medium-level beta-gamma laboratory pilot facility

    International Nuclear Information System (INIS)

    Calor, J.N.; Mauborgne, B.; Montuir, M.

    2000-01-01

    The Process Development Laboratory (LDP) uses the ATALANTE C17 line for integral testing in order to develop and validate spent fuel reprocessing methods and for overall qualification of calculation codes. Line C 17 comprises shielded cells and glove boxes, equipped with centrifugal extractors and laboratory-scale mixer-settlers to test liquid-liquid extraction processes in an alpha and medium-level beta-gamma environment. The high reliability and precision of the process instrumentation and control system allow full control of operating parameters and comprehensive operating data recording, meeting the experimentation quality requirements necessary for qualifying calculation codes. Direct online spectrophotometric analysis at various points in the process provides real-time concentration data for vital elements, some of which are difficult to analyze offline because of their poor chemical stability. Online analyses, supplemented when necessary by gamma spectrometry, provide valuable process control input for reaching stabilized operating conditions. Fifteen radioactive test campaigns have been successfully completed since line C 17 was commissioned in June 1995. (authors)

  2. Screening of gamma radiation-induced pathogen resistance rice lines against Xanthomonas oryzae pv. oryzae

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Chan Ju; Lee, Ha Yeon; Kim, Woong Bom; Ahmad, Raza; Moon, Jae Sun; Kwon, Suk Yoon [Korea Research Institute of Beoscience and Biotechnology, Daejeon (Korea, Republic of); Kim, Dong Sub [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2010-09-15

    Bacterial blight is one of the most serious diseases of rice (Oryza sativa L.), and it has been known that Xanthomonas oryzae pv. oryzae (Xoo) causes this disease symptom. To develop resistance rice cultivars against Xoo, 3,000 lines of M{sub 3}, which were irradiated with gamma ray, were tested by 'scissor-dip method' primarily, and 191 putative resistant lines were selected. In M{sub 4} generation, these lines were screened again with various ways such as measuring of symptom of bacterial blight in leaf, number of tiller, fresh weight, and phenotypic segregation ratio in next generation. Finally, six resistance lines were selected. RT-PCR analysis revealed that these lines displayed high level of R-genes such as Xa21, Pi36, and Pi-ta. These results indicate that mutations by gamma ray cause disruptions of regulatory signal transduction systems of these R-genes. Furthermore, these selected mutants could be useful for the development of rice cultivar resistant to Xoo.

  3. Comparative effects of RRR-alpha- and RRR-gamma-tocopherol on proliferation and apoptosis in human colon cancer cell lines.

    Science.gov (United States)

    Campbell, Sharon E; Stone, William L; Lee, Steven; Whaley, Sarah; Yang, Hongsong; Qui, Min; Goforth, Paige; Sherman, Devin; McHaffie, Derek; Krishnan, Koyamangalath

    2006-01-17

    Mediterranean societies, with diets rich in vitamin E isoforms, have a lower risk for colon cancer than those of northern Europe and the Americas. Vitamin E rich diets may neutralize free radicals generated by fecal bacteria in the gut and prevent DNA damage, but signal transduction activities can occur independent of the antioxidant function. The term vitamin E represents eight structurally related compounds, each differing in their potency and mechanisms of chemoprevention. The RRR-gamma-tocopherol isoform is found primarily in the US diet, while RRR-alpha-tocopherol is highest in the plasma. The effectiveness of RRR-alpha- and RRR-gamma-tocopherol at inhibiting cell growth and inducing apoptosis in colon cancer cell lines with varying molecular characteristics (SW480, HCT-15, HCT-116 and HT-29) and primary colon cells (CCD-112CoN, nontransformed normal phenotype) was studied. Colon cells were treated with and without RRR-alpha- or RRR-gamma-tocopherol using varying tocopherol concentrations and time intervals. Cell proliferation and apoptosis were measured using the trypan blue assay, annexin V staining, DNA laddering and caspase activation. Treatment with RRR-gamma-tocopherol resulted in significant cell death for all cancer cell lines tested, while RRR-alpha-tocopherol did not. Further, RRR-gamma-tocopherol treatment showed no cytotoxicity to normal colon cells CCD-112CoN at the highest concentration and time point tested. RRR-gamma-tocopherol treatment resulted in cleavage of PARP, caspase 3, 7, and 8, but not caspase 9. Differences in the percentage cell death and apoptosis were observed in different cell lines suggesting that molecular differences in these cell lines may influence the ability of RRR-gamma-tocopherol to induce cell death. This is the first study to demonstrate that multiple colon cancer cell lines containing varying genetic alterations will under go growth reduction and apoptosis in the presence of RRR-gamma-tocopherol without damage to

  4. Intense gamma-ray lines from hidden vector dark matter decay

    International Nuclear Information System (INIS)

    Arina, Chiara; Hambye, Thomas

    2009-12-01

    Scenarios with hidden, spontaneously broken, non-abelian gauge groups contain a natural dark matter candidate, the hidden vector, whose longevity is due to an accidental custodial symmetry in the renormalizable Lagrangian. Nevertheless, non-renormalizable dimension six operators break the custodial symmetry and induce the decay of the dark matter particle at cosmological times. We discuss in this paper the cosmic ray signatures of this scenario and we show that the decay of hidden vector dark matter particles generically produce an intense gamma ray line which could be observed by the Fermi-LAT experiment, if the scale of custodial symmetry breaking is close to the Grand Unification scale. This gamma line proceeds directly from a tree level dark matter 2-body decay in association with a Higgs boson. Within this model we also perform a determination of the relic density constraints taking into account the dark matter annihilation processes with one dark matter particle in the final state. The corresponding direct detection rates can be easily of order the current experimental sensitivities. (orig.)

  5. Intense gamma-ray lines from hidden vector dark matter decay

    Energy Technology Data Exchange (ETDEWEB)

    Arina, Chiara; Hambye, Thomas [Universite Libre de Bruxelles (Belgium). Service de Physique Theorique; Ibarra, Alejandro [Technische Univ. Muenchen, Garching (Germany). Physik-Department; Weniger, Christoph [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2009-12-15

    Scenarios with hidden, spontaneously broken, non-abelian gauge groups contain a natural dark matter candidate, the hidden vector, whose longevity is due to an accidental custodial symmetry in the renormalizable Lagrangian. Nevertheless, non-renormalizable dimension six operators break the custodial symmetry and induce the decay of the dark matter particle at cosmological times. We discuss in this paper the cosmic ray signatures of this scenario and we show that the decay of hidden vector dark matter particles generically produce an intense gamma ray line which could be observed by the Fermi-LAT experiment, if the scale of custodial symmetry breaking is close to the Grand Unification scale. This gamma line proceeds directly from a tree level dark matter 2-body decay in association with a Higgs boson. Within this model we also perform a determination of the relic density constraints taking into account the dark matter annihilation processes with one dark matter particle in the final state. The corresponding direct detection rates can be easily of order the current experimental sensitivities. (orig.)

  6. Intense gamma-ray lines from hidden vector dark matter decay

    International Nuclear Information System (INIS)

    Arina, Chiara; Hambye, Thomas; Ibarra, Alejandro; Weniger, Christoph

    2010-01-01

    Scenarios with hidden, spontaneously broken, non-abelian gauge groups contain a natural dark matter candidate, the hidden vector, whose longevity is due to an accidental custodial symmetry in the renormalizable Lagrangian. Nevertheless, non-renormalizable dimension six operators break the custodial symmetry and induce the decay of the dark matter particle at cosmological times. We discuss in this paper the cosmic ray signatures of this scenario and we show that the decay of hidden vector dark matter particles generically produce an intense gamma ray line which could be observed by the Fermi-LAT experiment, if the scale of custodial symmetry breaking is close to the Grand Unification scale. This gamma line proceeds directly from a tree level dark matter 2-body decay in association with a Higgs boson. Within this model we also perform a determination of the relic density constraints taking into account the dark matter annihilation processes with one dark matter particle in the final state. The corresponding direct detection rates can be easily of order the current experimental sensitivities

  7. Gamma-ray-line astronomy: the case of 26Al

    International Nuclear Information System (INIS)

    Prantzos, N.

    1986-07-01

    The recent detection of the 1.8 MeV line in the galactic plane, attributed to the decay of ∼ 3 Solar mass of radioactive 26 Al, brought closer together the disciplines of gamma-ray Astronomy and Nuclear Astrophysics. A review is presented here of the possible production mechanisms and sites of 26 Al in the Galaxy, with an emphasis on the role of massive, mass losing stars

  8. Proliferative and antiproliferative effects of interferon-gamma and tumor necrosis factor-alpha on cell lines derived from cervical and ovarian malignancies

    International Nuclear Information System (INIS)

    Mutch, D.G.; Massad, L.S.; Kao, M.S.; Collins, J.L.

    1990-01-01

    Four human cell lines derived from cervical carcinomas (ME-180, SiHa, HT-3, and MS751) and three human cell lines derived from ovarian carcinomas (SK-OV-3, Caov-3, and NIH:OVCAR-3) were analyzed in vitro to determine the effect of recombinant interferon-gamma and recombinant human tumor necrosis factor-alpha on cell growth and survival. The effects of interferon-gamma, tumor necrosis factor-alpha, and both interferon-gamma and tumor necrosis factor-alpha on cell growth were measured after 24 and 72 hours of incubation by the incorporation of chromium 51. The results of this analysis showed that all seven cell lines were resistant to the antiproliferative action of tumor necrosis factor-alpha, that the growth of most cell lines was inhibited by interferon-gamma by 72 hours of incubation, and that after 72 hours of incubation all cell lines demonstrated a synergistic antiproliferative response to the combination of interferon-gamma and tumor necrosis factor-alpha. However, the effects of these cytokines on cell growth were found to differ among cell lines and varied with the concentration and the duration of incubation. The growth of one cell line (Caov-3) was stimulated by both tumor necrosis factor-alpha and interferon-gamma. These results suggest that the clinical effects of these cytokines on the growth of gynecologic cancers may be more complex than previously supposed

  9. On-line interrogation of pebble bed reactor fuel using passive gamma-ray spectrometry

    Science.gov (United States)

    Chen, Jianwei

    The Pebble Bed Reactor (PBR) is a helium-cooled, graphite-moderated high temperature nuclear power reactor. In addition to its inherently safe design, a unique feature of this reactor is its multipass fuel cycle in which graphite fuel pebbles (of varying enrichment) are randomly loaded and continuously circulated through the core until they reach their prescribed end-of-life burnup limit (˜80,000--100,000 MWD/MTU). Unlike the situation with conventional light water reactors (LWRs), depending solely on computational methods to perform in-core fuel management will be highly inaccurate. As a result, an on-line measurement approach becomes the only accurate method to assess whether a particular pebble has reached its end-of-life burnup limit. In this work, an investigation was performed to assess the feasibility of passive gamma-ray spectrometry assay as an approach for on-line interrogation of PBR fuel for the simultaneous determination of burnup and enrichment on a pebble-by-pebble basis. Due to the unavailability of irradiated or fresh pebbles, Monte Carlo simulations were used to study the gamma-ray spectra of the PBR fuel at various levels of burnup. A pebble depletion calculation was performed using the ORIGEN code, which yielded the gamma-ray source term that was introduced into the input of an MCNP simulation. The MCNP simulation assumed the use of a high-purity coaxial germanium detector. Due to the lack of one-group high temperature reactor cross sections for ORIGEN, a heterogeneous MCNP model was developed to describe a typical PBR core. Subsequently, the code MONTEBURNS was used to couple the MCNP model and ORIGEN. This approach allowed the development of the burnup-dependent, one-group spectral-averaged PBR cross sections to be used in the ORIGEN pebble depletion calculation. Based on the above studies, a relative approach for performing the measurements was established. The approach is based on using the relative activities of Np-239/I-132 in combination

  10. Multi-dimensional analysis of high resolution {gamma}-ray data

    Energy Technology Data Exchange (ETDEWEB)

    Flibotte, S; Huttmeier, U J; France, G de; Haas, B; Romain, P; Theisen, Ch; Vivien, J P; Zen, J [Centre National de la Recherche Scientifique (CNRS), 67 - Strasbourg (France); Bednarczyk, P [Institute of Nuclear Physics, Cracow (Poland)

    1992-08-01

    High resolution {gamma}-ray multi-detectors capable of measuring high-fold coincidences with a large efficiency are presently under construction (EUROGAM, GASP, GAMMASPHERE). The future experimental progress in our understanding of nuclear structure at high spin critically depends on our ability to analyze the data in a multi-dimensional space and to resolve small photopeaks of interest from the generally large background. Development of programs to process such high-fold events is still in its infancy and only the 3-fold case has been treated so far. As a contribution to the software development associated with the EUROGAM spectrometer, we have written and tested the performances of computer codes designed to select multi-dimensional gates from 3-, 4- and 5-fold coincidence databases. The tests were performed on events generated with a Monte Carlo simulation and also on experimental data (triples) recorded with the 8{pi} spectrometer and with a preliminary version of the EUROGAM array. (author). 7 refs., 3 tabs., 1 fig.

  11. Applying ISO 11929:2010 Standard to detection limit calculation in least-squares based multi-nuclide gamma-ray spectrum evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kanisch, G., E-mail: guenter.kanisch@hanse.net

    2017-05-21

    The concepts of ISO 11929 (2010) are applied to evaluation of radionuclide activities from more complex multi-nuclide gamma-ray spectra. From net peak areas estimated by peak fitting, activities and their standard uncertainties are calculated by weighted linear least-squares method with an additional step, where uncertainties of the design matrix elements are taken into account. A numerical treatment of the standard's uncertainty function, based on ISO 11929 Annex C.5, leads to a procedure for deriving decision threshold and detection limit values. The methods shown allow resolving interferences between radionuclide activities also in case of calculating detection limits where they can improve the latter by including more than one gamma line per radionuclide. The co'mmon single nuclide weighted mean is extended to an interference-corrected (generalized) weighted mean, which, combined with the least-squares method, allows faster detection limit calculations. In addition, a new grouped uncertainty budget was inferred, which for each radionuclide gives uncertainty budgets from seven main variables, such as net count rates, peak efficiencies, gamma emission intensities and others; grouping refers to summation over lists of peaks per radionuclide.

  12. Effects of hematin and Moessbauer gamma-radiation on human osteosarcoma cell lines

    International Nuclear Information System (INIS)

    Ortalli, I.; Pedrazzi, G.; Fano, V.; Ma, W.; Cai, S.; Giuliani, N.; Passeri, M.

    1996-01-01

    In the present work it is reported an investigation on cultures of the human osteosarcoma cell line 'MG-63' and the human osteoblastic cell line 'HOBIT'. It is examined the combined effects of hematin and 14,4keV gamma-radiation from a Moessbauer source. Preliminary results seem to confirm the trend already observed for the bone marrow system. Different degrees of growth inhibition were observed when hematin alone and hematin plus gamma-rays were administered to the cultures. It was previously found that hematin has no toxic effects on normal cells up to a concentration of 10 -4 M, but the same concentration produces various degrees of inhibition on cultures of tumor cells. While no significant effect could be attributed to irradiation alone, hematin plus irradiations show a larger inhibition than that expected for pure additive effects

  13. Spectrum analysis with indoor multi-channels gamma-rays spectrometer (NaI(Tl))

    International Nuclear Information System (INIS)

    Hou Shengli; Fan Weihua

    2005-01-01

    Two calculational methods for analyzing the spectrum which measured by indoor low background multi-channels gamma-rays spectrometer (Na(Tl)) to get the specific activity of 226 Ra, 232 Th and 40 K of the sample are discussed, they are the spectrum analysis method and the characteristic energy peak method (inverse matrix method) respectively. The sample spectrum are analyzed with the program designed according to the two methods, and compared with the results by HPGe gamma-rays spectrometer, showing that the relative deviation is ≤10% with the two methods. (authors)

  14. New information on the $\\beta$-decay of $^{11}$Li from Doppler broadened $\\gamma$-lines

    CERN Document Server

    Fynbo, H O U; Cederkäll, J; Courtin, S; Dessagne, P; Jonson, B; Le Scornet, G; Nilsson, T; Nyman, G H; Poirier, E; Riisager, K; Tengblad, O; Wilhelmsen, K

    2004-01-01

    The $\\gamma$-ray spectrum following $\\beta$-decay of $^{11}$Li has been remeasured at the ISOLDE facility at CERN. Two new transitions were observed through the use of large Ge-detectors. Most $\\gamma$-decays will follow P-delayed neutron emission. Information on the energy of the neutron is derived from analysis of the $\\gamma$-line-shape and used to construct a partial decay scheme for $^{11}$Li. Lifetime values for the 1$^{-}$ and 2$^{-}$ levels in $^{10}$Be are also derived. A new partial decay scheme is presented. (43 refs).

  15. Decaying vs. annihilating dark matter in light of a tentative gamma-ray line

    International Nuclear Information System (INIS)

    Buchmüller, Wilfried; Garny, Mathias

    2012-01-01

    Recently reported tentative evidence for a gamma-ray line in the Fermi-LAT data is of great potential interest for identifying the nature of dark matter. We compare the implications for decaying and annihilating dark matter taking the constraints from continuum gamma-rays, antiproton flux and morphology of the excess into account. We find that higgsino and wino dark matter are excluded, also for nonthermal production. Generically, the continuum gamma-ray flux severely constrains annihilating dark matter. Consistency of decaying dark matter with the spatial distribution of the Fermi-LAT excess would require an enhancement of the dark matter density near the Galactic center

  16. Decaying vs annihilating dark matter in light of a tentative gamma-ray line

    Energy Technology Data Exchange (ETDEWEB)

    Buchmueller, Wilfried; Garny, Mathias

    2012-06-15

    Recently reported tentative evidence for a gamma-ray line in the Fermi-LAT data is of great potential interest for identifying the nature of dark matter. We compare the implications for decaying and annihilating dark matter taking the constraints from continuum gamma-rays, antiproton flux and morphology of the excess into account. We find that higgsino and wino dark matter are excluded, also for nonthermal production. Generically, the continuum gamma-ray ux severely constrains annihilating dark matter. Consistency of decaying dark matter with the spatial distribution of the Fermi-LAT excess would require an enhancement of the dark matter density near the Galactic center.

  17. Instrumental and atmospheric background lines observed by the SMM gamma-ray spectrometer

    Science.gov (United States)

    Share, G. H.; Kinzer, R. L.; Strickman, M. S.; Letaw, J. R.; Chupp, E. L.

    1989-01-01

    Preliminary identifications of instrumental and atmospheric background lines detected by the gamma-ray spectrometer on NASA's Solar Maximum Mission satellite (SMM) are presented. The long-term and stable operation of this experiment has provided data of high quality for use in this analysis. Methods are described for identifying radioactive isotopes which use their different decay times. Temporal evolution of the features are revealed by spectral comparisons, subtractions, and fits. An understanding of these temporal variations has enabled the data to be used for detecting celestial gamma-ray sources.

  18. Gamma-ray boxes from axion-mediated dark matter

    International Nuclear Information System (INIS)

    Ibarra, Alejandro; Gehler, Sergio López; Pato, Miguel; Lee, Hyun Min; Park, Wan-Il

    2013-01-01

    We compute the gamma-ray output of axion-mediated dark matter and derive the corresponding constraints set by recent data. In such scenarios the dark matter candidate is a Dirac fermion that pair-annihilates into axions and/or scalars. Provided that the axion decays (at least partly) into photons, these models naturally give rise to a box-shaped gamma-ray spectrum that may present two distinct phenomenological behaviours: a narrow box, resembling a line at half the dark matter mass, or a wide box, spanning an extensive energy range up to the dark matter mass. Remarkably, we find that in both cases a sizable gamma-ray flux is predicted for a thermal relic without fine-tuning the model parameters nor invoking boost factors. This large output is in line with recent Fermi-LAT observations towards the galactic centre region and is on the verge of being excluded. We then make use of the Fermi-LAT and H.E.S.S. data to derive robust, model-independent upper limits on the dark matter annihilation cross section for the narrow and wide box scenarios. H.E.S.S. constraints, in particular, turn out to match the ones from Fermi-LAT at hundreds of GeV and extend to multi-TeV masses. Future Čerenkov telescopes will likely probe gamma-ray boxes from thermal dark matter relics in the whole multi-TeV range, a region hardly accessible to direct detection, collider searches and other indirect detection strategies

  19. Development of a fast multi-line x-ray CT detector for NDT

    International Nuclear Information System (INIS)

    Hofmann, T.; Nachtrab, F.; Schlechter, T.; Mühlbauer, J.; Schröpfer, S.; Firsching, M.; Uhlmann, N.; Neubauer, H.; Ernst, J.; Schweiger, T.; Oberst, M.; Meyer, A.

    2015-01-01

    Typical X-ray detectors for non-destructive testing (NDT) are line detectors or area detectors, like e.g. flat panel detectors. Multi-line detectors are currently only available in medical Computed Tomography (CT) scanners. Compared to flat panel detectors, line and multi-line detectors can achieve much higher frame rates. This allows time-resolved 3D CT scans of an object under investigation. Also, an improved image quality can be achieved due to reduced scattered radiation from object and detector themselves. Another benefit of line and multi-line detectors is that very wide detectors can be assembled easily, while flat panel detectors are usually limited to an imaging field with a size of approx. 40 × 40 cm 2 at maximum. The big disadvantage of line detectors is the limited number of object slices that can be scanned simultaneously. This leads to long scan times for large objects. Volume scans with a multi-line detector are much faster, but with almost similar image quality. Due to the promising properties of multi-line detectors their application outside of medical CT would also be very interesting for NDT. However, medical CT multi-line detectors are optimized for the scanning of human bodies. Many non-medical applications require higher spatial resolutions and/or higher X-ray energies. For those non-medical applications we are developing a fast multi-line X-ray detector.In the scope of this work, we present the current state of the development of the novel detector, which includes several outstanding properties like an adjustable curved design for variable focus-detector-distances, conserving nearly uniform perpendicular irradiation over the entire detector width. Basis of the detector is a specifically designed, radiation hard CMOS imaging sensor with a pixel pitch of 200 μ m. Each pixel has an automatic in-pixel gain adjustment, which allows for both: a very high sensitivity and a wide dynamic range. The final detector is planned to have 256 lines of

  20. Expedited, uniform processing of multi-vendor gamma test data

    International Nuclear Information System (INIS)

    Zimmerman, R.E.

    2002-01-01

    Aim: Acceptance testing of gamma camera performance is time consuming. When data is collected from different vendors image format and methodology differences can result in disjointed and difficult to compare results. Even when performing NEMA specified tests consistent processing of data from multi-vendor cameras results in methodological inconsistencies. A more uniform and consistent method to process data collected from gamma cameras would be a boon to those involved in acquiring and processing such test data. Methods and Materials: Image J is an image processing program freely available on the Web at http://rsb.info.nih.gov/ij/. It can be run using a normal Web browser or installed on any computer. Since it is written in Java it is platform and operating system independent. Image J is very extensible, object based and has a large international user community in many imaging disciplines. Extensions to Image J are written using the Java programming language and the internal macro recording facility. Image J handles multiple image formats useful in nuclear medicine including DICOM, RAW, BMP, JPG, Interfile, AVI and QT. Extensions have been written to process and determine gamma camera intrinsic and extrinsic uniformity, COR errors, planar extrinsic resolution and reconstructed spatial resolution. The testing and processing adhere closely to NEMA specified procedures and result in quantitative measures of performance traceable to NEMA and manufacturers specifications. Results and Conclusions: Extensions to Image J written specifically to process gamma camera acceptance test data have resulted in considerable decrease in time to complete the analysis and allows a consistent, vendor independent, method to measure performance of cameras from multiple vendors. Quality control images from multiple camera vendors are also easily processed in a consistent fashion. The availability of this or similar platform and vendor independent software should lead to more complete

  1. Development of an on-line tritium monitor with gamma-ray rejection and energy discrimination

    International Nuclear Information System (INIS)

    Cox, S.A.; Yule, T.J.; Bennett, E.F.

    1981-01-01

    With the prospect of large fusion facilities coming on-line in the not-too-distant future, it is becoming increasingly important that an on-line tritium-monitoring system be developed which is capable of detecting small amounts of released tritium. Since tritium oxide is some 400 times as hazardous as elemental tritium, it is necessary to distinguish between the two in order to properly evaluate the hazard. Presently available on-line instrumentation has marginal sensitivity, is unable to distinguish between the two forms of tritium, and has poor discrimination against background gamma radiation and air activation products. The objective of our program is to develop a monitoring system with the capability of distinguishing between the two forms of tritium, detecting tritium with a sensitivity of a fraction of an MPC/sub a/ (1 MPC/sub a/ = 5. x 10 - 6 Ci/M 3 ) for the oxide, and discriminating against gamma activity and airborne activity other than tritium

  2. GAMMA RAYS FROM THE TYCHO SUPERNOVA REMNANT: MULTI-ZONE VERSUS SINGLE-ZONE MODELING

    Energy Technology Data Exchange (ETDEWEB)

    Atoyan, Armen [Department of Mathematics, Concordia University, 1455 de Maisonneuve Blvd. West, Montreal, Quebec H3G 1M8 (Canada); Dermer, Charles D., E-mail: atoyan@mathstat.concordia.ca, E-mail: charles.dermer@nrl.navy.mil [Code 7653, Naval Research Laboratory, Washington, DC 20375-5352 (United States)

    2012-04-20

    Recent Fermi and VERITAS observations of the prototypical Type Ia supernova remnant (SNR) Tycho have discovered {gamma}-rays with energies E in the range 0.4 GeV {approx}< E {approx}< 10 TeV. Crucial for the theory of Galactic cosmic-ray origin is whether the {gamma}-rays from SNRs are produced by accelerated hadrons (protons and ions) or by relativistic electrons. Here we show that strong constraints on the leptonic model imposed in the framework of the commonly used single-zone model are essentially removed if the analysis of the broadband radiation spectrum of Tycho is done in the two-zone (or, in general, multi-zone) approach, which is likely to apply to every SNR. Importantly, we show that the single-zone approach may underpredict the {gamma}-ray fluxes by an order of magnitude. A hadronic model can, however, also fit the detected {gamma}-ray spectrum. The difference between {gamma}-ray fluxes of hadronic and leptonic origins becomes significant only at {approx}<300 MeV, which could be revealed by spectral measurements of Tycho and other SNRs at these energies.

  3. Time stamp technique using a nuclear emulsion multi-stage shifter for gamma-ray telescope

    International Nuclear Information System (INIS)

    Takahashi, Satoru; Aoki, Shigeki; Rokujo, Hiroki; Hamada, Kaname; Komatsu, Masahiro; Morishima, Kunihiro; Nakamura, Mitsuhiro; Nakano, Toshiyuki; Niwa, Kimio; Sato, Osamu; Yoshioka, Teppei; Kodama, Koichi

    2010-01-01

    Nuclear emulsion has a potential use as a gamma-ray telescope with high angular resolution. For this application it is necessary to know the time when each track was recorded in the emulsion. In previous experiments using nuclear emulsion, various efforts were used to associate time to nuclear emulsion tracks and to improve the time resolution. Using a high speed readout system for nuclear emulsion together with a clock-based multi-stage emulsion shifter, we invented a technique to give a time-stamp to emulsion tracks and greatly improve the time resolution. A test experiment with a 2-stage shifter was used to demonstrate the principle of multi-stage shifting, and we achieved a time resolution 1.5 s for 12.1 h (about 1 part in 29 000) with the time stamp reliability 97% and the time stamp efficiency 98%. This multi-stage shifter can achieve the time resolution required for a gamma-ray telescope and can also be applied to another cosmic ray observations and accelerator experiments using nuclear emulsion.

  4. SMM observations of gamma-ray transients. 2: A search for gamma-ray lines between 400 and 600 keV from the Crab Nebula

    Science.gov (United States)

    Harris, Michael J.; Share, Gerald H.; Leising, Mark D.

    1994-01-01

    We have search spectra obtained by the Solar Maximum Mission Gamma-Ray Spectrometer during 1981-1988 for evidence of transient gamma-ray lines from the Crab Nebula which have been reported by previous experiments at energies 400-460 keV and 539 keV. We find no evidence for significant emission in any of these lines on time scales between aproximately 1 day and approximately 1 yr. Our 3 sigma upper limits on the transient flux during 1 d intervals are approximately equal to 2.2 x 10(exp -3) photons/sq cm/s for narrow lines at any energy, and approximately equal to 2.9 x 10(exp -3) photons/sq cm/s for the 539 keV line if it is as broad as 42 keV Full Width at Half Maximum (FWHM). We also searched our data during the approximately 5 hr period on 1981 June 6 during which Owens, Myers, & Thompson (1985) reported a strong line at 405 keV. We detected no line down to a 3 upper sigma limit of 3.3 x 10(exp -3) photons/sq cm/s in disagreement with the flux 7.2 +/- 2.1 x 10(exp -3) photos/sq cm/s measured by Owens et al.

  5. Interferon-gamma sensitizes colonic epithelial cell lines to physiological and therapeutic inducers of colonocyte apoptosis.

    LENUS (Irish Health Repository)

    O'Connell, J

    2012-02-03

    Homeostasis in the colonic epithelium is achieved by a continuous cycle of proliferation and apoptosis, in which imbalances are associated with disease. Inflammatory bowel disease (IBD) and colon cancer are associated with either excessive or insufficient apoptosis of colonic epithelial cells, respectively. By using two colonic epithelial cell lines, HT29 and SW620, we investigated how the epithelial cell\\'s sensitivity to apoptosis was regulated by the proinflammatory cytokine interferon-gamma (IFN-gamma). We found that IFN-gamma sensitized HT29 cells, and to a lesser extent SW620, to diverse inducers of apoptosis of physiologic or therapeutic relevance to the colon. These apoptosis inducers included Fas (CD95\\/APO-1) ligand (FasL), short-chain fatty acids, and chemotherapeutic drugs. The extent of IFN-gamma-mediated apoptosis sensitization in these two cell lines correlated well with the degree of IFN-gamma-mediated upregulation of the proapoptotic protease caspase-1. Although IFN-gamma alone effectively sensitized HT29 cells to apoptosis, inclusion of the protein synthesis inhibitor cyclohexamide (CHX) during apoptotic challenge was necessary for maximal sensitization of SW620. The requirement of CHX to sensitize SW620 cells to apoptosis implies a need to inhibit translation of antiapoptotic proteins absent from HT29. In particular, the antiapoptotic protein Bcl-2 was strongly expressed in SW620 cells but absent from HT29. Our results indicate that IFN-gamma increases the sensitivity of colonic epithelial cells to diverse apoptotic stimuli in concert, via upregulation of caspase-1. Our findings implicate caspase-1 and Bcl-2 as important central points of control determining the general sensitivity of colonic epithelial cells to apoptosis.

  6. Modeling Auditory-Haptic Interface Cues from an Analog Multi-line Telephone

    Science.gov (United States)

    Begault, Durand R.; Anderson, Mark R.; Bittner, Rachael M.

    2012-01-01

    The Western Electric Company produced a multi-line telephone during the 1940s-1970s using a six-button interface design that provided robust tactile, haptic and auditory cues regarding the "state" of the communication system. This multi-line telephone was used as a model for a trade study comparison of two interfaces: a touchscreen interface (iPad)) versus a pressure-sensitive strain gauge button interface (Phidget USB interface controllers). The experiment and its results are detailed in the authors' AES 133rd convention paper " Multimodal Information Management: Evaluation of Auditory and Haptic Cues for NextGen Communication Dispays". This Engineering Brief describes how the interface logic, visual indications, and auditory cues of the original telephone were synthesized using MAX/MSP, including the logic for line selection, line hold, and priority line activation.

  7. EVIDENCE FOR ENHANCED {sup 3}HE IN FLARE-ACCELERATED PARTICLES BASED ON NEW CALCULATIONS OF THE GAMMA-RAY LINE SPECTRUM

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, R. J. [Code 7650, Naval Research Laboratory, Washington, DC 20375 (United States); Kozlovsky, B. [Tel Aviv University, Tel Aviv (Israel); Share, G. H., E-mail: murphy@ssd5.nrl.navy.mil, E-mail: benz@wise.tau.ac.il, E-mail: share@astro.umd.edu [University of Maryland, College Park, MD 20742 (United States)

    2016-12-20

    The {sup 3}He abundance in impulsive solar energetic particle (SEP) events is enhanced up to several orders of magnitude compared to its photospheric value of [{sup 3}He]/[{sup 4}He] = 1–3 × 10{sup −4}. Interplanetary magnetic field and timing observations suggest that these events are related to solar flares. Observations of {sup 3}He in flare-accelerated ions would clarify the relationship between these two phenomena. Energetic {sup 3}He interactions in the solar atmosphere produce gamma-ray nuclear-deexcitation lines, both lines that are also produced by protons and α particles and lines that are essentially unique to {sup 3}He. Gamma-ray spectroscopy can, therefore, reveal enhanced levels of accelerated {sup 3}He. In this paper, we identify all significant deexcitation lines produced by {sup 3}He interactions in the solar atmosphere. We evaluate their production cross sections and incorporate them into our nuclear deexcitation-line code. We find that enhanced {sup 3}He can affect the entire gamma-ray spectrum. We identify gamma-ray line features for which the yield ratios depend dramatically on the {sup 3}He abundance. We determine the accelerated {sup 3}He/ α ratio by comparing these ratios with flux ratios measured previously from the gamma-ray spectrum obtained by summing the 19 strongest flares observed with the Solar Maximum Mission Gamma-Ray Spectrometer. All six flux ratios investigated show enhanced {sup 3}He, confirming earlier suggestions. The {sup 3}He/ α weighted mean of these new measurements ranges from 0.05 to 0.3 (depending on the assumed accelerated α /proton ratio) and has a <1 × 10{sup −3} probability of being consistent with the photospheric value. With the improved code, we can now exploit the full potential of gamma-ray spectroscopy to establish the relationship between flare-accelerated ions and {sup 3}He-rich SEPs.

  8. On-line real time gamma analysis of primary coolant

    International Nuclear Information System (INIS)

    Kalechstein, W.; Kupca, S.; Lipsett, J.J.

    1985-10-01

    The evolution of failed fuel monitoring at CANDU power stations is briefly summarized and the design of the latest system for failed fuel detection at a multi-unit power station is described. At each reactor, the system employs a germanium spectrometer combined with a novel spectrum analyzer that simultaneously accumulates the gamma-ray spectrum of the coolant and provides the control room with the concentration of radioisotope activity in the coolant for the gaseous fission products Xe-133, Xe-135, Kr-88 and I-131 in real time and with statistical precision independent of count rate. A gross gamma monitor is included to provide independent information on the level of radioactivity in the coolant and extend the measurement range at very high count rates. A central computer system archives spectra received from all four spectrum analyzers and provides both the activity concentrations and the release rates of specified isotopes. Compared with previous systems the current design offers improvements in that the activity concentrations are updated much more frequently, improved tools are provided for long term surveillance of the heat transport system and the monitor is more reliable and less costly

  9. Measurements of environmental gamma-ray spectra using a multi-element TL dosemeter

    International Nuclear Information System (INIS)

    Furuta, Sadaaki; Boetter-Jensen, L.; Nielsen, S.P.

    1986-12-01

    A method to estimate the energy distribution and dose of environmental gamma radiation was developed using a multielement TL dosemeter. Experimentally obtained energy responses from a multi-element TL dosemeter with different kinds of filters were used to calculate the energy distribution and related dose by the SAND-II computer code. The code was originally developed to estimate the neutron flux using a multiple foil activation method. Measurements were made at several locations with the multi-element TL dosemeter and comparisons were made with results from a NaI(Tl) scintillation detector and a high-pressure ionization chamber. (author)

  10. Advanced multi-dimensional imaging of gamma-ray radiation

    International Nuclear Information System (INIS)

    Woodring, Mitchell; Beddingfield, David; Souza, David; Entine, Gerald; Squillante, Michael; Christian, James; Kogan, Alex

    2003-01-01

    The tracking of radiation contamination and distribution has become a high-priority US DOE task. To support DOE needs, Radiation Monitoring Devices Inc. has been actively carrying out research and development on a gamma-radiation imager, RadCam 2000 TM . The imager is based upon a position-sensitive PMT coupled to a scintillator near a MURA coded aperture. The modulated gamma flux detected by the PSPMT is mathematically decoded to produce images that are computer displayed in near real time. Additionally, we have developed a data-manipulation scheme which allows a multi-dimensional data array, comprised of x position, y position, and energy, to be used in the imaging process. In the imager software a gate can be set on a specific isotope energy to reveal where in the field of view the gated data lies or, conversely, a gate can be set on an area in the field of view to examine what isotopes are present in that area. This process is complicated by the FFT decoding process used with the coded aperture; however, we have achieved excellent performance and results are presented here

  11. Neutron induced gamma spectrometry for on-line compositional analysis in coal conversion and fluidized-bed combustion plants

    International Nuclear Information System (INIS)

    Herzenberg, C.L.; O'Fallon, N.M.; Yarlagadda, B.S.; Doering, R.W.; Cohn, C.E.; Porges, K.G.; Duffey, D.

    1977-01-01

    Nuclear techniques involving relatively penetrating radiation may offer the possibility of non-invasive, continuous on-line instrumental monitoring which is representative of the full process stream. Prompt gamma rays following neutron capture are particularly attractive because the penetrating power of the neutrons and the, typically several MeV, capture gammas makes possible interrogation of material within a pipe. We are evaluating neutron capture gamma techniques for this application, both for elemental composition monitoring and for mass-flow measurement purposes, and this paper will present some recent work on composition analysis by neutron induced gamma spectrometry

  12. Exact multi-line soliton solutions of noncommutative KP equation

    International Nuclear Information System (INIS)

    Wang, Ning; Wadati, Miki

    2003-01-01

    A method of solving noncommutative linear algebraic equations plays a key role in the extension of the ∂-bar -dressing on the noncommutative space-time manifold. In this paper, a solution-generating method of noncommutative linear algebraic equations is proposed. By use of the proposed method, a class of multi-line soliton solutions of noncommutative KP (ncKP) equation is constructed explicitly. The method is expected to be of use for constructions of noncommutative soliton equations. The significance of the noncommutativity of coordinates is investigated. It is found that the noncommutativity of the space-time coordinate has a role to split the spatial waveform of the classical multi-line solitons and reform it to a new configuration. (author)

  13. Multi-shot analysis of the gamma reaction history diagnostic

    International Nuclear Information System (INIS)

    Sayre, D. B.; Bernstein, L. A.; Church, J. A.; Stoeffl, W.; Herrmann, H. W.

    2012-01-01

    The gamma reaction history diagnostic at the National Ignition Facility has the capability to determine a number of important performance metrics for cryogenic deuterium-tritium implosions: the fusion burn width, bang time and yield, as well as the areal density of the compressed ablator. Extracting those values from the measured γ rays of an implosion, requires accounting for a γ-ray background in addition to the impulse response function of the instrument. To address these complications, we have constructed a model of the γ-ray signal, and are developing a simultaneous multi-shot fitting routine to constrain its parameter space.

  14. Dose mapping of the multi-purpose gamma irradiation facility

    Energy Technology Data Exchange (ETDEWEB)

    Cabalfin, E G; Lanuza, L G; Villamater, D T [Irradiation Services, Nuclear Services and Training Division, Philippine Nuclear Research Institute, Quezon City (Philippines)

    1989-12-01

    In radiation processing, reliable dosimetry constitutes a very important part of process control and quality assurance. Radiation dosimetry is the only acceptable method to guarantee that the irradiated product has undergone the correct radiation treatment. In preparation therefore, for the routine operation of the newly installed multi-purpose gamma irradiation facility at the Philippine Nuclear Research Institute (PNRI), dose mapping distribution studies were undertaken. Results of dose distribution in air as well as in dummy product are presented. The effects of product bulk density, product geometry and product to source distance on minimum absorbed dose and uniformity ratio have been determined. (Author).

  15. Dose mapping of the multi-purpose gamma irradiation facility

    International Nuclear Information System (INIS)

    Cabalfin, E.G.; Lanuza, L.G.; Villamater, D.T.

    1989-01-01

    In radiation processing, reliable dosimetry constitutes a very important part of process control and quality assurance. Radiation dosimetry is the only acceptable method to guarantee that the irradiated product has undergone the correct radiation treatment. In preparation therefore, for the routine operation of the newly installed multi-purpose gamma irradiation facility at the Philippine Nuclear Research Institute (PNRI), dose mapping distribution studies were undertaken. Results of dose distribution in air as well as in dummy product are presented. The effects of product bulk density, product geometry and product to source distance on minimum absorbed dose and uniformity ratio have been determined. (Author)

  16. A GIF++ Gamma Irradiation Facility at the SPS H4 Beam Line

    CERN Document Server

    Capéans-Garrido, M; Linssen, L; Moll, M; Rembser, C

    2009-01-01

    The current document describes a proposal to implement a new gamma irradiation facility, combined with a high-energy particle beam in the SPS H4 beam line in hall EHN1. This new GIF++ facility is motivated by strong needs from the LHC and sLHC detector and accelerator communities for the tests of LHC components and systems.

  17. FBILI method for multi-level line transfer

    Science.gov (United States)

    Kuzmanovska, O.; Atanacković, O.; Faurobert, M.

    2017-07-01

    Efficient non-LTE multilevel radiative transfer calculations are needed for a proper interpretation of astrophysical spectra. In particular, realistic simulations of time-dependent processes or multi-dimensional phenomena require that the iterative method used to solve such non-linear and non-local problem is as fast as possible. There are several multilevel codes based on efficient iterative schemes that provide a very high convergence rate, especially when combined with mathematical acceleration techniques. The Forth-and-Back Implicit Lambda Iteration (FBILI) developed by Atanacković-Vukmanović et al. [1] is a Gauss-Seidel-type iterative scheme that is characterized by a very high convergence rate without the need of complementing it with additional acceleration techniques. In this paper we make the implementation of the FBILI method to the multilevel atom line transfer in 1D more explicit. We also consider some of its variants and investigate their convergence properties by solving the benchmark problem of CaII line formation in the solar atmosphere. Finally, we compare our solutions with results obtained with the well known code MULTI.

  18. Multi-Mode Operation for On-line Uninterruptible Power Supply System

    DEFF Research Database (Denmark)

    Lu, Jinghang; Savaghebi, Mehdi; Golestan, Saeed

    2018-01-01

    To enhance the robustness and disturbance rejection ability of an on-line uninterruptible power supply (UPS) system, an Internal Model Control (IMC)-based DC-link voltage regulation method is proposed in this paper. Furthermore, the multi-mode operations of the on-line UPS system are investigated...

  19. Multi-messenger Light Curves from Gamma-Ray Bursts in the Internal Shock Model

    Energy Technology Data Exchange (ETDEWEB)

    Bustamante, Mauricio [Center for Cosmology and AstroParticle Physics (CCAPP), The Ohio State University, Columbus, OH 43210 (United States); Heinze, Jonas; Winter, Walter [Deutsches Elektronen-Synchrotron (DESY), Platanenallee 6, D-15738 Zeuthen (Germany); Murase, Kohta, E-mail: bustamanteramirez.1@osu.edu, E-mail: walter.winter@desy.de, E-mail: jonas.heinze@desy.de, E-mail: murase@psu.edu [Center for Particle and Gravitational Astrophysics, The Pennsylvania State University, University Park, PA16802 (United States)

    2017-03-01

    Gamma-ray bursts (GRBs) are promising as sources of neutrinos and cosmic rays. In the internal shock scenario, blobs of plasma emitted from a central engine collide within a relativistic jet and form shocks, leading to particle acceleration and emission. Motivated by present experimental constraints and sensitivities, we improve the predictions of particle emission by investigating time-dependent effects from multiple shocks. We produce synthetic light curves with different variability timescales that stem from properties of the central engine. For individual GRBs, qualitative conclusions about model parameters, neutrino production efficiency, and delays in high-energy gamma-rays can be deduced from inspection of the gamma-ray light curves. GRBs with fast time variability without additional prominent pulse structure tend to be efficient neutrino emitters, whereas GRBs with fast variability modulated by a broad pulse structure can be inefficient neutrino emitters and produce delayed high-energy gamma-ray signals. Our results can be applied to quantitative tests of the GRB origin of ultra-high-energy cosmic rays, and have the potential to impact current and future multi-messenger searches.

  20. Multi-messenger light curves from gamma-ray bursts in the internal shock model

    Energy Technology Data Exchange (ETDEWEB)

    Bustamante, Mauricio [Ohio State Univ., Columbus, OH (United States). Center for Cosmology and AstroParticle Physics (CCAPP); Ohio State Univ., Columbus, OH (United States). Dept. of Physics; Murase, Kohta [Pennsylvania State Univ., University Park, PA (United States). Center for Particle and Gravitational Astrophysics; Pennsylvania State Univ., University Park, PA (United States). Dept. of Astronomy and Astrophysics; Winter, Walter [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)

    2016-06-15

    Gamma-ray bursts (GRBs) are promising as sources of neutrinos and cosmic rays. In the internal shock scenario, blobs of plasma emitted from a central engine collide within a relativistic jet and form shocks, leading to particle acceleration and emission. Motivated by present experimental constraints and sensitivities, we improve the predictions of particle emission by investigating time-dependent effects from multiple shocks. We produce synthetic light curves with different variability timescales that stem from properties of the central engine. For individual GRBs, qualitative conclusions about model parameters, neutrino production efficiency, and delays in high-energy gamma rays can be deduced from inspection of the gamma-ray light curves. GRBs with fast time variability without additional prominent pulse structure tend to be efficient neutrino emitters, whereas GRBs with fast variability modulated by a broad pulse structure tend to be inefficient neutrino emitters and produce delayed high-energy gamma-ray signals. Our results can be applied to quantitative tests of the GRB origin of ultra-high-energy cosmic rays, and have the potential to impact current and future multi-messenger searches.

  1. Chemical and microbiological assessments of the multi mixture treated by gamma radiation

    International Nuclear Information System (INIS)

    Goncalves, Cinthia Graciele

    2008-01-01

    In Brazil, the multi mixture have being used since the eighties as an alternative against severe infantile malnutrition of the poorest population. However, its use is still reason of controversies mainly due to: the presence of anti nutritional factors, the microbiological quality and the nutritional value. Considering the routine use of multi mixture in the region, this work aimed to evaluate samples of multi mixture were collected in the metropolitan area of the City of Belo Horizonte/MG for determining the anti nutritional factors (phytic and oxalic acids), the microbiological quality, the centesimal and mineral composition, and still the induced effect in these factors of the gamma radiation. For the analyses, the samples passed by the process of gamma irradiation at doses of: 2, 4, 6, 8 and 10 kGy and then were evaluated anti nutritional factors (phytic acid and oxalic), the microbiological quality (yeasts and molds, Salmonella, Coagulase positive Staphylococcus, Bacillus cereus, coliform to 45 deg C) to full percentage (moisture, ash, proteins, carbohydrates and lipids) and the efficiency of the method of Paramagnetic Electronic Resonance (EPR) in the detection of irradiated samples. The mineral composition of the samples was carried out by the irradiation by Neutronic Activation. The methods used were searched in literature. The obtained results suggest that the concentration of the phytic and oxalic acids can not be appropriated for the children with severe nutritional deficit and that it would be necessary additional control in their daily ingestion due to the absorption of essential minerals. In general the samples had presented acceptable microbiological quality for consumption, except by one of it. The data of the centesimal and mineral composition, in the usually recommended portions, showed lower concentration than recommended for children. Any significant alteration in phytic and oxalic acids as well as in the centesimal composition were detected

  2. Spectral measurements of gamma radiation streaming through ducts

    International Nuclear Information System (INIS)

    Meenakshisundaram, P.K.; Bhatnagar, V.M.; Raghunath, V.M.; Gopinath, D.V.

    1979-01-01

    The paper presents the spectral measurements of gamma radiation streaming through multi-legged rectangular concrete ducts for cesium-137 and cobald-60 sources. Effect of lead lining the inner surface of the duct on the streaming radiation spectrum and optimization of liner thickness for minimum streaming radiation dose have been studied. For three-legged ducts, a comparative analysis of lead lining the entire duct as against lining any one or both the corners of the duct is reported. It is seen that lead lining any one of the corners would reduce the streaming radiation dose by a factor of 5 to 12. Lining both the corners which is nearly as effective as lining the entire duct reduces the dose by a factor of 16 to 60 depending on the soruce energy and duct dimensions. (orig.)

  3. An improved, computer-based, on-line gamma monitor for plutonium anion exchange process control

    International Nuclear Information System (INIS)

    Pope, N.G.; Marsh, S.F.

    1987-06-01

    An improved, low-cost, computer-based system has replaced a previously developed on-line gamma monitor. Both instruments continuously profile uranium, plutonium, and americium in the nitrate anion exchange process used to recover and purify plutonium at the Los Alamos Plutonium Facility. The latest system incorporates a personal computer that provides full-feature multichannel analyzer (MCA) capabilities by means of a single-slot, plug-in integrated circuit board. In addition to controlling all MCA functions, the computer program continuously corrects for gain shift and performs all other data processing functions. This Plutonium Recovery Operations Gamma Ray Energy Spectrometer System (PROGRESS) provides on-line process operational data essential for efficient operation. By identifying abnormal conditions in real time, it allows operators to take corrective actions promptly. The decision-making capability of the computer will be of increasing value as we implement automated process-control functions in the future. 4 refs., 6 figs

  4. Nomogram for Determining Shield Thickness for Point and Line Sources of Gamma Rays

    Energy Technology Data Exchange (ETDEWEB)

    Joenemalm, C; Malen, K

    1966-10-15

    A set of nomograms is given for the determination of the required shield thickness against gamma radiation. The sources handled are point and infinite line sources with shields of Pb, Fe, magnetite concrete (p = 3.6), ordinary concrete (p = 2.3) or water. The gamma energy range covered is 0.5 - 10 MeV. The nomograms are directly applicable for source and dose points on the surfaces of the shield. They can easily be extended to source and dose points in other positions by applying a geometrical correction. Also included are data for calculation of the source strength for the most common materials and for fission product sources.

  5. Nomogram for Determining Shield Thickness for Point and Line Sources of Gamma Rays

    International Nuclear Information System (INIS)

    Joenemalm, C.; Malen, K

    1966-10-01

    A set of nomograms is given for the determination of the required shield thickness against gamma radiation. The sources handled are point and infinite line sources with shields of Pb, Fe, magnetite concrete (p = 3.6), ordinary concrete (p = 2.3) or water. The gamma energy range covered is 0.5 - 10 MeV. The nomograms are directly applicable for source and dose points on the surfaces of the shield. They can easily be extended to source and dose points in other positions by applying a geometrical correction. Also included are data for calculation of the source strength for the most common materials and for fission product sources

  6. Multi objective optimization of line pack management of gas pipeline system

    International Nuclear Information System (INIS)

    Chebouba, A

    2015-01-01

    This paper addresses the Line Pack Management of the ''GZ1 Hassi R'mell-Arzew'' gas pipeline. For a gas pipeline system, the decision-making on the gas line pack management scenarios usually involves a delicate balance between minimization of the fuel consumption in the compression stations and maximizing gas line pack. In order to select an acceptable Line Pack Management of Gas Pipeline scenario from these two angles for ''GZ1 Hassi R'mell- Arzew'' gas pipeline, the idea of multi-objective decision-making has been introduced. The first step in developing this approach is the derivation of a numerical method to analyze the flow through the pipeline under transient isothermal conditions. In this paper, the solver NSGA-II of the modeFRONTIER, coupled with a matlab program was used for solving the multi-objective problem

  7. Applications of multi-pinhole gamma camera collimation to tomography and image enhancement

    Science.gov (United States)

    Simpson, D. R.

    1981-06-01

    Multi-pinhole gamma camera collimation was introduced in the field of emission tomography. This collimation process simultaneously produces several images covering a limited angular range, which may then be recombined to obtain tomographic slices of the object imaged. A possible method for improving the images obtained by this technique by combining two multi-pinhole views taken 90 deg apart was investigated. Collimators were designed and built both for tomography and imaging tablet disintegration, and computer programs were written to reconstruct the images by simple backprojection and by filtered backprojection. The use of multi-pinhole collimators to image the disintegration of tablets in vivo was clearly demonstrated. Phantom tests done in vitro were capable of imaging defects as small as 5 sq mm, while images made with real tablets both in vitro and in vivo readily showed the onset and progress of the tablet disintegration.

  8. Gamma-line intensity difference method for sup 1 sup 1 sup 7 sup m Sn at high resolution

    CERN Document Server

    Remeikis, V; Mazeika, K

    1998-01-01

    The method for detection of small differences in the gamma-spectrum line intensity for the radionuclide in different environments has been developed for measurements at high resolution. The experiments were realized with the pure germanium planar detector. Solution of the methodical problems allowed to measure the relative difference DELTA IOTA subgamma/IOTA subgamma=(3.4+-1.5)*10 sup - sup 4 of the sup 1 sup 1 sup 7 sup m Sn 156.02 keV gamma-line intensity for the radionuclide in SnO sub 2 with respect to SnS from the difference in the gamma-spectra. The error of the result is caused mainly by the statistical accuracy. It is limited by the highest counting rate at sufficiently high energy resolution and relatively short half-life of sup 1 sup 1 sup 7 sup m Sn. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-10-01

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

  10. Applications of multi-pinhole gamma camera collimation to tomography and image enhancement

    International Nuclear Information System (INIS)

    Simpson, D.R.

    1981-01-01

    Recently, multi-pinhole gamma camera collimation has been introduced in the field of emission tomography. This collimation process simultaneously produces several images covering a limited angular range, which may then be recombined to obtain tomographic slices of the object imaged. This study has investigated a possible method for improving the images obtained by this technique by two multi-pinhole views taken 90 0 apart. During the course of this work, multi-pinhole collimation was also applied to in vivo imaging of the disintegration of tablets. Collimmators were designed and built both for tomography and imaging tablet disintegration, and computer programs were written to reconstruct the images by simple backprojection and by filtered backprojection. The use of multi-pinhole collimators to image the disintegration of tablets in vivo was clearly demonstrated. Phantom tests done in vitro were capable of imaging defects as small as 5 mm 2 , while images made with real tablets both in vitro and in vivo readily showed the onset and progress of the tablet disintegration. Further experiments are planned using this technique to measure gastric emptying times disintegration times of various tablet formulations. Limitations of multi-pinhole technique included problems such as limited ranges of viewing and artifacts introduced due to incomplete sampling

  11. Application of Multi-Layered Polyurethane Foams for Flat-Walled Anechoic Linings

    DEFF Research Database (Denmark)

    Xu, J. F.; Buchholz, Jörg; Fricke, Fergus R.

    2006-01-01

    of the application of multi-layered polyurethane foams as the flat-walled anechoic lining. The investigation includes aspects such as the efficacy of a single layer of material, the minimum number of layers of linings to achieve the minimum overall thickness for low (100Hz), mid (250Hz) and high (500Hz) cut...

  12. A Droop Line Tracking Control for Multi-terminal VSC-HVDC Transmission System

    DEFF Research Database (Denmark)

    Irnawan, Roni; Silva, Filipe Miguel Faria da; Bak, Claus Leth

    2018-01-01

    Generally, a voltage-sourced converter (VSC) within a multi-terminal HVDC (MTDC) system can be operated either in constant DC voltage, constant flow (AC active power or DC current) or DC voltage droop control. These control modes can be easily represented as the droop characteristic line with dif......Generally, a voltage-sourced converter (VSC) within a multi-terminal HVDC (MTDC) system can be operated either in constant DC voltage, constant flow (AC active power or DC current) or DC voltage droop control. These control modes can be easily represented as the droop characteristic line...

  13. Photometry of the 4686 A emission line of gamma(2) Velorum from the South Pole

    International Nuclear Information System (INIS)

    Taylor, M.

    1990-01-01

    An automated optical telescope located at the Amundsen-Scott South Pole station on Antarctica, has been used to obtain more than 78 h of photometry of the He II emission line (4686 A) of the spectroscopic binary gamma(2) Velorum. These data were obtained on seven different days during the 1987 austral winter; the longest continuous run spans 19 h. Two independent period search techniques have been used to search for periodic behavior in the strength of the He II emission line of this Wolf-Rayet star. They are: (1) power spectrum analysis and (2) a first-order sine function fit to the data using least squares. Various multiplicities of a period on the order of 1.3 h with amplitudes of a few percent are found in most of these data. According to recent theoretical models of Wolf-Rayet stars, fluctuations in the He II emission line may indicate vibrational instability in gamma(2) Vel. These pulsations may, in turn, give rise to shocks which propagate outward and which may provide the necessary conditions for periodic changes in the state of a given region of the atmosphere to occur. 15 refs

  14. Multi-objective Analysis for a Sequencing Planning of Mixed-model Assembly Line

    Science.gov (United States)

    Shimizu, Yoshiaki; Waki, Toshiya; Yoo, Jae Kyu

    Diversified customer demands are raising importance of just-in-time and agile manufacturing much more than before. Accordingly, introduction of mixed-model assembly lines becomes popular to realize the small-lot-multi-kinds production. Since it produces various kinds on the same assembly line, a rational management is of special importance. With this point of view, this study focuses on a sequencing problem of mixed-model assembly line including a paint line as its preceding process. By taking into account the paint line together, reducing work-in-process (WIP) inventory between these heterogeneous lines becomes a major concern of the sequencing problem besides improving production efficiency. Finally, we have formulated the sequencing problem as a bi-objective optimization problem to prevent various line stoppages, and to reduce the volume of WIP inventory simultaneously. Then we have proposed a practical method for the multi-objective analysis. For this purpose, we applied the weighting method to derive the Pareto front. Actually, the resulting problem is solved by a meta-heuristic method like SA (Simulated Annealing). Through numerical experiments, we verified the validity of the proposed approach, and discussed the significance of trade-off analysis between the conflicting objectives.

  15. A 0.8–8 GHz Multi-Section Coupled Line Balun

    Directory of Open Access Journals (Sweden)

    Srikanth Itapu

    2015-04-01

    Full Text Available In this work, we propose a wideband multi-section transforming coupled-line balun using near equal length transmission line elements. The resulting design is realized by cascading several coupled-lines with minimal discontinuities. The multi-section Chebyshev matching optimizes bandwidth at the expense of passband ripple. The proposed design delivers good impedance matching and consistent 180° phase shift over 0.8–8 GHz frequency spectrum. Furthermore, the need for vias in conventional balun designs is relaxed by replacing the short-circuited (SC terminal by its equivalent dual open-circuited (OC element. The proposed design is simulated, fabricated, and measured. Both simulated and measured results are in a good agreement, and show an input port matching of below −9.7 dB over the design bandwidth, with a maximum phase and amplitude imbalance of 2.1° and 0.9 dB, respectively.

  16. Multi-mode operations for on-line uninterruptible power supply

    DEFF Research Database (Denmark)

    Lu, Jinghang; Savaghebi, Mehdi; Guan, Yajuan

    2018-01-01

    In this paper, the multi-mode operation of the on-line UPS system is investigated and corresponding control strategies are proposed. The proposed control strategies are able to achieve the seamless transition in traditional normal mode, PV-aided normal mode, enhanced eco-mode and burn-in test mod...

  17. Selection and evaluation of soybean lines derived from gamma irradiation for rust resistance

    International Nuclear Information System (INIS)

    Smutkupt, S.; Wongpiyasatid, A.; Lamseejan, S.

    1983-01-01

    In 1979, seeds of 11 soybean cultivars were gamma irradiated with 15 and 30 krad. Treated and control seeds of each cultivar were planted in the rainy season. In the rainy season of 1980, M 3 populations were screened for rust resistance in Nong Hoi Valley and Mae Joe Experiment Station, both in Chiang Main province. The IWGSR rust rating system was used. Based upon the slow growth of rust on soybean plants, 6 and 115 plants were selected from 2,802 control plants and from 28,824 treated plants, respectively. Selected lines were evaluated in Nong Hoi Valley in the rainy season of 1981. Sixteen selections with average good seed yield per plant and low percentage of shrivelled seeds were obtained. Among them, two lines, namely G8586/Line number 81-1-072 and S.J. 4/Line number 81-1-037 gave the higher average seed yield per plant than other lines. They are at present in a preliminary yield trial in Chiang Mai. Chiang Mai. (author)

  18. Adaptive Response to ionizing Radiation Induced by Low Doses of Gamma Rays in Human Lymphoblastoid Cell Lines

    International Nuclear Information System (INIS)

    Seong, Jin Sil; Suh, Chang Ok; Kim, Gwi Eon

    1994-01-01

    When cells are exposed to low doses of a mutagenic or clastogenic agents, they often become less sensitive to the effects of a higher does administered subsequently. Such adaptive responses were first described in Escherichia coli and mammalian cells to low doses of an alkylating agent. Since most of the studies have been carried out with human lymphocytes, it is urgently necessary to study this effect in different cellular systems. Its relation with inherent cellular radiosensitivity and underlying mechanism also remain to be answered. In this study, adaptive response by 1 cGy of gamma rays was investigated in three human lymphoblastoid cell lines which were derived from ataxia telangiectasia homozygote, ataxia telangiectasia heterozygote, and normal individual. Experiments were carried out by delivering 1 cGy followed by 50 cGy of gamma radiation and chromatid breaks were scored as an endpoint. The results indicate that prior exposure to 1 cGy of gamma rays reduces the number of chromatid breaks induced by subsequent higher does (50 cGy). The expression of this adaptive response was similar among three cell lines despite of their different radiosensitivity. When 3-aminobenzamide, an inhibitor of poly (ADP-ribose) polymerase, was added after 50 cGy, adaptive responses were abolished in all the tested cell lines. Therefore it is suggested that the adaptive response can be observed in human lymphoblastoid cell lines. Which was first documented through this study. The expression of adaptive response was similar among the cell lines regardless of their radiosensitivity. The elimination of the adaptive response by 3-aminobenzamide is consistent with the proposal that this adaptive response is the result of the induction of a certain chromosomal repair mechanism

  19. GARLIC, a shielding program for GAmma Radiation from Line- and Cylinder-sources

    Energy Technology Data Exchange (ETDEWEB)

    Roos, Matts

    1959-07-15

    GARLIC is a program for computing the gamma ray flux or dose rate at a shielded idotropic point detector, due to a line source or the line equivalent of a cylindrical source. The source strength distribution along the line must be either uniform or an arbitrary part of the positive half-cycle of a cosine function. The line source can be oriented arbitrarily with respect to the main shield and the detector, except that the detector must not be located on the line source or on its extension. The main source is a homogeneous plane slab in which scattered radiation is accounted for by multiplying each point element of the line source by a point source build-up factor inside the integral over the point elements. Between, the main shield and the line source additional shields can be introduced, which are either plane slabs, parallel to the main shield, or cylindrical rings, coaxial with the line source. Scattered radiation in the additional shields can only be accounted for by constant build-up factors outside the integral. GARLIC-xyz is an extended version particularly suited for the frequently met problem of shielding a room containing a large number of line sources in different positions. The program computes the angles and linear dimensions of a problem for GARLIC when the positions of the detector point and the end points of the line source are given as points in an arbitrary rectangular coordinate system. As an example the isodose curves in water are presented for a monoenergetic cosine-distributed line source at several source energies and for an operating fuel element of the Swedish reactor R3.

  20. HIV multi-drug resistance at first-line antiretroviral failure and subsequent virological response in Asia

    Science.gov (United States)

    Jiamsakul, Awachana; Sungkanuparph, Somnuek; Law, Matthew; Kantor, Rami; Praparattanapan, Jutarat; Li, Patrick CK; Phanuphak, Praphan; Merati, Tuti; Ratanasuwan, Winai; Lee, Christopher KC; Ditangco, Rossana; Mustafa, Mahiran; Singtoroj, Thida; Kiertiburanakul, Sasisopin

    2014-01-01

    Introduction First-line antiretroviral therapy (ART) failure often results from the development of resistance-associated mutations (RAMs). Three patterns, including thymidine analogue mutations (TAMs), 69 Insertion (69Ins) and the Q151M complex, are associated with resistance to multiple-nucleoside reverse transcriptase inhibitors (NRTIs) and may compromise treatment options for second-line ART. Methods We investigated patterns and factors associated with multi-NRTI RAMs at first-line failure in patients from The TREAT Asia Studies to Evaluate Resistance – Monitoring study (TASER-M), and evaluated their impact on virological responses at 12 months after switching to second-line ART. RAMs were compared with the IAS-USA 2013 mutations list. We defined multi-NRTI RAMs as the presence of either Q151M; 69Ins; ≥2 TAMs; or M184V+≥1 TAM. Virological suppression was defined as viral load (VL) Malaysia and Philippines were included. There were 97/105 (92%) patients harbouring ≥1 RAMs at first-line failure, 39/105 with multi-NRTI RAMs: six with Q151M; 24 with ≥2 TAMs; and 32 with M184V+≥1 TAM. Factors associated with multi-NRTI RAMs were CD4 ≤200 cells/µL at genotyping (OR=4.43, 95% CI [1.59–12.37], p=0.004) and ART duration >2 years (OR=6.25, 95% CI [2.39–16.36], p<0.001). Among 87/105 patients with available VL at 12 months after switch to second-line ART, virological suppression was achieved in 85%. The median genotypic susceptibility score (GSS) for the second-line regimen was 2.00. Patients with ART adherence ≥95% were more likely to be virologically suppressed (OR=9.33, 95% CI (2.43–35.81), p=0.001). Measures of patient resistance to second-line ART, including the GSS, were not significantly associated with virological outcome. Conclusions Multi-NRTI RAMs at first-line failure were associated with low CD4 level and longer duration of ART. With many patients switching to highly susceptible regimens, good adherence was still crucial in achieving

  1. On-Line Multi-Damage Scanning Spatial-Wavenumber Filter Based Imaging Method for Aircraft Composite Structure

    Directory of Open Access Journals (Sweden)

    Yuanqiang Ren

    2017-05-01

    Full Text Available Structural health monitoring (SHM of aircraft composite structure is helpful to increase reliability and reduce maintenance costs. Due to the great effectiveness in distinguishing particular guided wave modes and identifying the propagation direction, the spatial-wavenumber filter technique has emerged as an interesting SHM topic. In this paper, a new scanning spatial-wavenumber filter (SSWF based imaging method for multiple damages is proposed to conduct on-line monitoring of aircraft composite structures. Firstly, an on-line multi-damage SSWF is established, including the fundamental principle of SSWF for multiple damages based on a linear piezoelectric (PZT sensor array, and a corresponding wavenumber-time imaging mechanism by using the multi-damage scattering signal. Secondly, through combining the on-line multi-damage SSWF and a PZT 2D cross-shaped array, an image-mapping method is proposed to conduct wavenumber synthesis and convert the two wavenumber-time images obtained by the PZT 2D cross-shaped array to an angle-distance image, from which the multiple damages can be directly recognized and located. In the experimental validation, both simulated multi-damage and real multi-damage introduced by repeated impacts are performed on a composite plate structure. The maximum localization error is less than 2 cm, which shows good performance of the multi-damage imaging method. Compared with the existing spatial-wavenumber filter based damage evaluation methods, the proposed method requires no more than the multi-damage scattering signal and can be performed without depending on any wavenumber modeling or measuring. Besides, this method locates multiple damages by imaging instead of the geometric method, which helps to improve the signal-to-noise ratio. Thus, it can be easily applied to on-line multi-damage monitoring of aircraft composite structures.

  2. Statistical Methods in Assembly Quality Management of Multi-Element Products on Automatic Rotor Lines

    Science.gov (United States)

    Pries, V. V.; Proskuriakov, N. E.

    2018-04-01

    To control the assembly quality of multi-element mass-produced products on automatic rotor lines, control methods with operational feedback are required. However, due to possible failures in the operation of the devices and systems of automatic rotor line, there is always a real probability of getting defective (incomplete) products into the output process stream. Therefore, a continuous sampling control of the products completeness, based on the use of statistical methods, remains an important element in managing the quality of assembly of multi-element mass products on automatic rotor lines. The feature of continuous sampling control of the multi-element products completeness in the assembly process is its breaking sort, which excludes the possibility of returning component parts after sampling control to the process stream and leads to a decrease in the actual productivity of the assembly equipment. Therefore, the use of statistical procedures for continuous sampling control of the multi-element products completeness when assembled on automatic rotor lines requires the use of such sampling plans that ensure a minimum size of control samples. Comparison of the values of the limit of the average output defect level for the continuous sampling plan (CSP) and for the automated continuous sampling plan (ACSP) shows the possibility of providing lower limit values for the average output defects level using the ACSP-1. Also, the average sample size when using the ACSP-1 plan is less than when using the CSP-1 plan. Thus, the application of statistical methods in the assembly quality management of multi-element products on automatic rotor lines, involving the use of proposed plans and methods for continuous selective control, will allow to automating sampling control procedures and the required level of quality of assembled products while minimizing sample size.

  3. Gamma-ray dose rate in air on the subway lines in Tokyo metropolitan area

    International Nuclear Information System (INIS)

    Ogawa, Masayuki; Hosoda, Masahiro; Ogashiwa, Susumu; Fukushi, Masahiro

    2008-01-01

    Measurements of gamma-ray dose rates in air were performed on 12 subway lines in Tokyo from the perspective of health physics, because the subways are commonly used for commuting in the Tokyo metropolitan area. The results showed that the maximum dose rate (36.5 nGy/h) was 1.6 times higher than that of the minimum one (23.3 nGy/h), and that the dose rate in the subway car was 33% lower than the outside. Also the results strongly suggested that the dose rates depend on the concentration of natural radionuclide around the subway lines and the platform structures rather than the depth. (author)

  4. MULTI-LINE STOKES INVERSION FOR PROMINENCE MAGNETIC-FIELD DIAGNOSTICS

    International Nuclear Information System (INIS)

    Casini, R.; Lopez Ariste, A.; Paletou, F.; Leger, L.

    2009-01-01

    We present test results on the simultaneous inversion of the Stokes profiles of the He I lines at 587.6 nm (D 3 ) and 1083.0 nm in prominences (90 deg. scattering). We created data sets of synthetic Stokes profiles for the case of quiescent prominences (B -3 of the peak intensity for the polarimetric sensitivity of the simulated observations. In this work, we focus on the error analysis for the inference of the magnetic field vector, under the usual assumption that the prominence can be assimilated to a slab of finite optical thickness with uniform magnetic and thermodynamic properties. We find that the simultaneous inversion of the two lines significantly reduces the errors on the inference of the magnetic field vector, with respect to the case of single-line inversion. These results provide a solid justification for current and future instrumental efforts with multi-line capabilities for the observations of solar prominences and filaments.

  5. Gamma-ray line emission from 26Al produced by Wolf-Rayet stars

    International Nuclear Information System (INIS)

    Prantzos, N.; Casse, M.; Gros, M.; Arnould, M.

    1985-08-01

    The recent satellite observations of the 1.8 MeV line from the decay of 26 Al has given a new impetus to the study of the nucleosynthesis of 26 Al. In this communication we discuss the production and ejection of 26 Al by massive mass-losing stars (Of and WR stars), in the light of recent stellar models. We also derive the longitude distribution of the 26 Al gamma-ray line emission produced by the galactic collection of WR stars, based on various estimates of their radial distribution. This longitude profile provides i) a specific signature of massive stars on the background of other potential 26 Al sources, as novae, supernovae, certain red giants and possibly AGB stars and ii) a possible tool to improve the data analysis of the HEAO 3 and SMM experiments

  6. BATSE gamma-ray burst line search. 2: Bayesian consistency methodology

    Science.gov (United States)

    Band, D. L.; Ford, L. A.; Matteson, J. L.; Briggs, M.; Paciesas, W.; Pendleton, G.; Preece, R.; Palmer, D.; Teegarden, B.; Schaefer, B.

    1994-01-01

    We describe a Bayesian methodology to evaluate the consistency between the reported Ginga and Burst and Transient Source Experiment (BATSE) detections of absorption features in gamma-ray burst spectra. Currently no features have been detected by BATSE, but this methodology will still be applicable if and when such features are discovered. The Bayesian methodology permits the comparison of hypotheses regarding the two detectors' observations and makes explicit the subjective aspects of our analysis (e.g., the quantification of our confidence in detector performance). We also present non-Bayesian consistency statistics. Based on preliminary calculations of line detectability, we find that both the Bayesian and non-Bayesian techniques show that the BATSE and Ginga observations are consistent given our understanding of these detectors.

  7. Evaluation of angular distributions and production cross-sections for discrete gamma lines in iron

    International Nuclear Information System (INIS)

    Savin, M.V.; Livke, A.V.; Zvenigorodskij, A.G.

    2001-01-01

    The experimental data were compiled and the angular distributions and production cross-sections for the E γ = 846.8, 1238.3 and 1810.8 keV discrete gamma-lines evaluated. The Legendre polynomial coefficients describing the angular distributions in the energy range up to E n = 14.0 MeV and cross-section values in the E n = 0.85-19.0 MeV range were evaluated. (author)

  8. Feasibility study of applying a multi-channel analysis model to on-line core monitoring system

    International Nuclear Information System (INIS)

    In, W. K.; Yoo, Y. J.; Hwang, D. H.; Jun, T. H.

    1998-01-01

    A feasibility study was performed to evaluate the effect of implementing a multi-channel analysis model in on-line core monitoring system. A simplified thermal-hydraulic model has been used in the on-line core monitoring system of digital PWR. The design procedure, core thermal margin and computation time were investigated in case of replacing the simplified model with the multi-channel analysis model. For the given ranges of limiting conditions for operation in Yonggwang Unit 3 Cycle 1, the minimum DNBR of the simplified thermal-hydraulic code CETOP-D was compared to that of the multi-channel analysis code MATRA. A CETOP-D tuning is additionally required to ensure the accurate and conservative DNBR calculation but the MATRA tuning is not necessary. MATRA appeared to increase the DNBR overpower margin from 2.5% to 6% over the CETOP-D margin. MATRA took approximately 1 second to compute DNBR on the HP9000 workstation system, which is longer than the DNBR computation time of CETOP-D. It is, however, fast enough to perform the on-line monitoring of DNBR. It can be therefore concluded that the application of the multi-channel analysis model MATRA in the on-line core monitoring system is feasible

  9. POLARIZED LINE FORMATION IN MULTI-DIMENSIONAL MEDIA. III. HANLE EFFECT WITH PARTIAL FREQUENCY REDISTRIBUTION

    International Nuclear Information System (INIS)

    Anusha, L. S.; Nagendra, K. N.

    2011-01-01

    In two previous papers, we solved the polarized radiative transfer (RT) equation in multi-dimensional (multi-D) geometries with partial frequency redistribution as the scattering mechanism. We assumed Rayleigh scattering as the only source of linear polarization (Q/I, U/I) in both these papers. In this paper, we extend these previous works to include the effect of weak oriented magnetic fields (Hanle effect) on line scattering. We generalize the technique of Stokes vector decomposition in terms of the irreducible spherical tensors T K Q , developed by Anusha and Nagendra, to the case of RT with Hanle effect. A fast iterative method of solution (based on the Stabilized Preconditioned Bi-Conjugate-Gradient technique), developed by Anusha et al., is now generalized to the case of RT in magnetized three-dimensional media. We use the efficient short-characteristics formal solution method for multi-D media, generalized appropriately to the present context. The main results of this paper are the following: (1) a comparison of emergent (I, Q/I, U/I) profiles formed in one-dimensional (1D) media, with the corresponding emergent, spatially averaged profiles formed in multi-D media, shows that in the spatially resolved structures, the assumption of 1D may lead to large errors in linear polarization, especially in the line wings. (2) The multi-D RT in semi-infinite non-magnetic media causes a strong spatial variation of the emergent (Q/I, U/I) profiles, which is more pronounced in the line wings. (3) The presence of a weak magnetic field modifies the spatial variation of the emergent (Q/I, U/I) profiles in the line core, by producing significant changes in their magnitudes.

  10. Plant breeding by using radiation mutation - Selection of herbicide-resistant cell lines by using {gamma}-rays

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyo Yeon [Sunchun University, Sunchun (Korea); Seo, Yong Weon [Korea University, Seoul (Korea)

    2000-04-01

    In order to develop the herbicide resistant cell lines, micro calli derived from rice anther culture and mature seed of wheat cultivars were irradiated with gamma rays. 1) The callus was dedifferentiated by 7 or 21 day pretreatment at 7 deg. C in two rice cultivars, Ilpumbyeo ad Dongjinbyeo. 2) To check the optimum concentration of herbicide, three herbicides were tested with micro calli. 3) The optimum dose of gamma ray to seeds of wheat seemed to be from 100 to 150 Gy. 4) AFLP and RAPD technique were established to develope herbicide resistant molecular marker in rice. 34 refs., 10 figs., 5 tabs. (Author)

  11. HIV multi-drug resistance at first-line antiretroviral failure and subsequent virological response in Asia.

    Science.gov (United States)

    Jiamsakul, Awachana; Sungkanuparph, Somnuek; Law, Matthew; Kantor, Rami; Praparattanapan, Jutarat; Li, Patrick C K; Phanuphak, Praphan; Merati, Tuti; Ratanasuwan, Winai; Lee, Christopher K C; Ditangco, Rossana; Mustafa, Mahiran; Singtoroj, Thida; Kiertiburanakul, Sasisopin

    2014-01-01

    First-line antiretroviral therapy (ART) failure often results from the development of resistance-associated mutations (RAMs). Three patterns, including thymidine analogue mutations (TAMs), 69 Insertion (69Ins) and the Q151M complex, are associated with resistance to multiple-nucleoside reverse transcriptase inhibitors (NRTIs) and may compromise treatment options for second-line ART. We investigated patterns and factors associated with multi-NRTI RAMs at first-line failure in patients from The TREAT Asia Studies to Evaluate Resistance - Monitoring study (TASER-M), and evaluated their impact on virological responses at 12 months after switching to second-line ART. RAMs were compared with the IAS-USA 2013 mutations list. We defined multi-NRTI RAMs as the presence of either Q151M; 69Ins; ≥ 2 TAMs; or M184V+≥ 1 TAM. Virological suppression was defined as viral load (VL) failure and (2) factors associated with virological suppression after 12 months on second-line. A total of 105 patients from 10 sites in Thailand, Hong Kong, Indonesia, Malaysia and Philippines were included. There were 97/105 (92%) patients harbouring ≥ 1 RAMs at first-line failure, 39/105 with multi-NRTI RAMs: six with Q151M; 24 with ≥ 2 TAMs; and 32 with M184V+≥ 1 TAM. Factors associated with multi-NRTI RAMs were CD4 ≤ 200 cells/µL at genotyping (OR=4.43, 95% CI [1.59-12.37], p=0.004) and ART duration >2 years (OR=6.25, 95% CI [2.39-16.36], pfailure were associated with low CD4 level and longer duration of ART. With many patients switching to highly susceptible regimens, good adherence was still crucial in achieving virological response. This emphasizes the importance of continued adherence counselling well into second-line therapy.

  12. Multi-group transport methods for high-resolution neutron activation analysis

    International Nuclear Information System (INIS)

    Burns, K. A.; Smith, L. E.; Gesh, C. J.; Shaver, M. W.

    2009-01-01

    The accurate and efficient simulation of coupled neutron-photon problems is necessary for several important radiation detection applications. Examples include the detection of nuclear threats concealed in cargo containers and prompt gamma neutron activation analysis for nondestructive determination of elemental composition of unknown samples. In these applications, high-resolution gamma-ray spectrometers are used to preserve as much information as possible about the emitted photon flux, which consists of both continuum and characteristic gamma rays with discrete energies. Monte Carlo transport is the most commonly used modeling tool for this type of problem, but computational times for many problems can be prohibitive. This work explores the use of multi-group deterministic methods for the simulation of neutron activation problems. Central to this work is the development of a method for generating multi-group neutron-photon cross-sections in a way that separates the discrete and continuum photon emissions so that the key signatures in neutron activation analysis (i.e., the characteristic line energies) are preserved. The mechanics of the cross-section preparation method are described and contrasted with standard neutron-gamma cross-section sets. These custom cross-sections are then applied to several benchmark problems. Multi-group results for neutron and photon flux are compared to MCNP results. Finally, calculated responses of high-resolution spectrometers are compared. Preliminary findings show promising results when compared to MCNP. A detailed discussion of the potential benefits and shortcomings of the multi-group-based approach, in terms of accuracy, and computational efficiency, is provided. (authors)

  13. Muon Beam Studies in the H4 beam line and the Gamma Irradiation Facility (GIF++)

    CERN Document Server

    Margraf, Rachel; CERN. Geneva. EN Department

    2017-01-01

    In this report, I summarize my work of detailed study and optimization of the muon beam configuration of H4 beam line in SPS North Area. Using Monte-Carlo simulations, I studied the properties and behavior of the muon beam in combination with the field of the large, spectrometer “ GOLIATH” magnet at -1.5, -1.0, 0, 1.0 and 1.5 Tesla, which is shown to affect the central x position of the muon beam that is delivered to the Gamma Irradiation Facility (GIF++). I also studied the muon beam for different configurations of the two XTDV beam dumps upstream of GIF++ in the H4 beam line. I will also discuss my role in mapping the magnetic field of the GOLIATH magnet in the H4 beam line.

  14. Comparison of Optical and Multi-Waveband Variations of Selected Gamma-ray Bright Blazars in 2012

    Science.gov (United States)

    Schultz, Benjamin; Jorstad, S. G.; Marscher, A. P.; Williamson, K. E.; Walker, G. E.

    2013-01-01

    We present multi-wavelength observations of several gamma-ray bright blazars. We combine optical data obtained with the 17-inch CCD telescope of Maria Mitchell Observatory with space- and ground-based observations carried out with a variety of instruments. These include a number of other optical telescopes, the Fermi Gamma-Ray Space Telescope at photon energies of 0.1-200 GeV, and the Swift satellite at 0.3-10 keV plus optical and UV wavelengths. Three of the observed blazars proved to be particularly active - BL Lac, Mrk501, and CTA-102. BL Lac was of special interest, displaying remarkable activity in multiple wavelengths during this observation period, including the optical, in which it underwent its largest observed flare in a number of years. In addition, CTA-102 has recently undergone an unprecedented multi-wavelength outburst. We cross-correlate the variations in the different wavebands in an effort to guide theoretical interpretations of the optical and high-energy emission from blazars. This project was supported by NSF/REU grant AST-0851892 and the Nantucket Maria Mitchell Association. The research at Boston University was supported in part by NSF grant AST-0907893 and by NASA through Fermi grant NNX11AQ03G.

  15. Librarian driven analysis of gamma ray spectra

    International Nuclear Information System (INIS)

    Kondrashov, V.; Petersone, I.

    2002-01-01

    For a set of a priori given radionuclides extracted from a general nuclide data library, the authors use median estimates of the gamma-peak areas and estimates of their errors to produce a list of possible radionuclides matching gamma ray line(s). The identification of a given radionuclide is obtained by searching for a match with the energy information of a database. This procedure is performed in an interactive graphic mode by markers that superimpose, on the spectral data, the energy information and yields provided by a general gamma ray data library. This library of experimental data includes approximately 17,000 gamma ray energy lines related to 756 known gamma emitter radionuclides listed by the ICRP. (author)

  16. SBS 0846+513: a New Gamma-ray Emitting Narrow-line Seyfert 1 Galaxy

    Science.gov (United States)

    D'Ammando, F.; Orienti, M.; Finke, J.; Raiteri, C. M.; Angelakis, E.; Fuhrmann, L.; Giroletti, M.; Hovatta, T.; Max-Moerbeck, W.; Perkins, J. S.; hide

    2012-01-01

    We report Fermi-LAT observations of the radio-loud AGN SBS 0846+513 (z=0.5835), optically classified as a Narrow-Line Seyfert 1 galaxy, together with new and archival radio-to-X-ray data. The source was not active at ?-ray energies during the first two years of Fermi operation. A significant increase in activity was observed during 2010 October-2011 August. In particular a strong gamma-ray flare was observed in 2011 June reaching an isotropic ?-ray luminosity (0.1-300 GeV) of 1.0×10(sup 48) erg s(sup -1), comparable to that of the brightest flat spectrum radio quasars, and showing spectral evolution in gamma rays. An apparent superluminal velocity of (8.2+/-1.5)c in the jet was inferred from 2011-2012 VLBA images, suggesting the presence of a highly relativistic jet. Both the power released by this object during the flaring activity and the apparent superluminal velocity are strong indications of the presence of a relativistic jet as powerful as those of blazars. In addition, variability and spectral properties in radio and gamma-ray bands indicate blazar-like behaviour, suggesting that, except for some distinct optical characteristics, SBS 0846+513 could be considered as a young blazar at the low end of the blazar's black hole mass distribution.

  17. Raft cultivation area extraction from high resolution remote sensing imagery by fusing multi-scale region-line primitive association features

    Science.gov (United States)

    Wang, Min; Cui, Qi; Wang, Jie; Ming, Dongping; Lv, Guonian

    2017-01-01

    In this paper, we first propose several novel concepts for object-based image analysis, which include line-based shape regularity, line density, and scale-based best feature value (SBV), based on the region-line primitive association framework (RLPAF). We then propose a raft cultivation area (RCA) extraction method for high spatial resolution (HSR) remote sensing imagery based on multi-scale feature fusion and spatial rule induction. The proposed method includes the following steps: (1) Multi-scale region primitives (segments) are obtained by image segmentation method HBC-SEG, and line primitives (straight lines) are obtained by phase-based line detection method. (2) Association relationships between regions and lines are built based on RLPAF, and then multi-scale RLPAF features are extracted and SBVs are selected. (3) Several spatial rules are designed to extract RCAs within sea waters after land and water separation. Experiments show that the proposed method can successfully extract different-shaped RCAs from HR images with good performance.

  18. LINE-BASED MULTI-IMAGE MATCHING FOR FAÇADE RECONSTRUCTION

    Directory of Open Access Journals (Sweden)

    T. A. Teo

    2012-07-01

    Full Text Available This research integrates existing LOD 2 building models and multiple close-range images for façade structural lines extraction. The major works are orientation determination and multiple image matching. In the orientation determination, Speeded Up Robust Features (SURF is applied to extract tie points automatically. Then, tie points and control points are combined for block adjustment. An object-based multi-images matching is proposed to extract the façade structural lines. The 2D lines in image space are extracted by Canny operator followed by Hough transform. The role of LOD 2 building models is to correct the tilt displacement of image from different views. The wall of LOD 2 model is also used to generate hypothesis planes for similarity measurement. Finally, average normalized cross correlation is calculated to obtain the best location in object space. The test images are acquired by a nonmetric camera Nikon D2X. The total number of image is 33. The experimental results indicate that the accuracy of orientation determination is about 1 pixel from 2515 tie points and 4 control points. It also indicates that line-based matching is more flexible than point-based matching.

  19. Adaptive response to ionizing radiation induced by low doses of gamma rays in human cell lines

    International Nuclear Information System (INIS)

    Seong, Jinsil; Chang, Ok Suh; Gwi, Eon Kim

    1995-01-01

    Purpose: The aim of this study was to investigate whether the adaptive response could be induced in human lymphoblastoid cell lines and human tumor cell lines. The time necessary for the expression of the adaptive response was also investigated. Materials and Methods: Three lymphoblastoid cell lines from ataxia telangiectasia (AT) homozygote (GM 1526), AT heterozygote (GM 3382), and normal individual (3402p) and two hepatoma cell lines, Hep G2 and Hep 3B, were used in this study. Experiments were carried out by delivering 0.01 Gy followed by 0.5 Gy of gamma radiation to the exponentially growing cells. The time necessary for the expression of the adaptive response was determined by varying the time interval between the two doses from 1 to 72 h. In some experiments, 3-aminobenzamide, a potent inhibitor of poly (ADP-ribose) polymerase, was added immediately after the 0.5 Gy exposure. The cultures were fixed 30 min (for the G 2 chromatid) and 6 h (for the S chromatid) after the 0.5 Gy exposure. Metaphase chromosome assay was carried out to score chromatid breaks as an end point. Results: A prior exposure to 0.01 Gy of gamma rays significantly reduced the number of chromatid breaks induced by subsequent higher doses (0.5 Gy) in all the tested cell lines. The magnitude of the adaptive response was similar among the cell lines despite their different radiosensitivities. In the G 2 chromatids, the adaptive response was observed both at short-time intervals, as early as 1 h, and at long-time intervals. In the S chromatids, however, the adaptive response was shown only at long-time intervals. When 3-aminobenzamide was added after the 0.5 Gy, the adaptive responses were abolished in all the experimental groups. Conclusion: The adaptive response was observed in human lymphoblastoid cell lines and hepatoma cell lines. The magnitude of the adaptive response did not seem to be related to the radiosensitivity of the cells. The elimination of the adaptive response with 3

  20. The dynamic time-over-threshold method for multi-channel APD based gamma-ray detectors

    Energy Technology Data Exchange (ETDEWEB)

    Orita, T., E-mail: orita.tadashi@jaea.go.jp [Japan Atomic Energy Agency, Fukushima (Japan); Shimazoe, K.; Takahashi, H. [Department of Nuclear Management and Engineering, The University of Tokyo, Bunkyō (Japan)

    2015-03-01

    t– Recent advances in manufacturing technology have enabled the use of multi-channel pixelated detectors in gamma-ray imaging applications. When obtaining gamma-ray measurements, it is important to obtain pulse height information in order to avoid unnecessary events such as scattering. However, as the number of channels increases, more electronics are needed to process each channel's signal, and the corresponding increases in circuit size and power consumption can result in practical problems. The time-over-threshold (ToT) method, which has recently become popular in the medical field, is a signal processing technique that can effectively avoid such problems. However, ToT suffers from poor linearity and its dynamic range is limited. We therefore propose a new ToT technique called the dynamic time-over-threshold (dToT) method [4]. A new signal processing system using dToT and CR-RC shaping demonstrated much better linearity than that of a conventional ToT. Using a test circuit with a new Gd{sub 3}Al{sub 2}Ga{sub 3}O{sub 12} (GAGG) scintillator and an avalanche photodiode, the pulse height spectra of {sup 137}Cs and {sup 22}Na sources were measured with high linearity. Based on these results, we designed a new application-specific integrated circuit (ASIC) for this multi-channel dToT system, measured the spectra of a {sup 22}Na source, and investigated the linearity of the system.

  1. Identification of the second mutation of BADH2 gene derived from rice mutant lines induced by gamma rays

    International Nuclear Information System (INIS)

    I Ishak

    2016-01-01

    The BADH2 gene acts as suppressor of 2-acetyl-1-pyrolline (2AP) biosynthesis in plants. 2AP is the volatile compound which provides fragrance in rice. Biosynthesis of 2AP occurs when BADH2 loses its function as suppressor gene. Aromatic rice cultivars naturally incur mutation of BADH2 gene at 8 bp. In this experiment, aromatic mutant rice lines derived from irradiation of Sintanur cultivar by gamma rays with dose of 100 Gy were studied in molecular level. These mutant lines were characterized at the M10 plantgeneration under the assumption that genetically these aromatic mutant rice lines were homozygotic. Several primers related to aroma in rice have been used for polymerase chain reaction (PCR) in a thermal cycler instrument. Gel electrophoreses were carried out using 1.5% agarose in TAE buffer. DNA fragments at 254 bp and 355 bp (base pair) were taken and amplified by primer for nucleotide sequencing of these fragments. Molecular identification and characterization after electrophoresis showed that the mutant line from AR1020 can be differentiated from AR.1080 at 254 bp. Nucleotide sequence data from of these DNA fragments showed that point mutations (deletions and substitutions) occurred at the BADH2 gene in exon 7; those are called second mutation and were caused by gamma rays effects. The Sintanur variety was used as check cultivar and its DNA sequence was compared to that of the AR.1020 mutant line. The results from both DNA sequences (from cv. Sintanur and AR.1020) derived from fragments at 254 bp show that point mutations occurred within exon 7 and earlier stop codon occurred in the AR.1020 mutant rice line. Further, the use of EA primer in PCR resulted in detection of deletion and substitution of nucleotides in the AR.1020 mutant line. (author)

  2. Constraints on gamma-ray burst and supernova progenitors through circumstellar absorption lines : II. Post-LBV Wolf-Rayet stars

    NARCIS (Netherlands)

    Marle, A.J.; Langer, N.; Garcia-Segura, G.

    2007-01-01

    Van Marle et al. (2005) showed that circumstellar absorption lines in early Type Ib/c supernova and gamma-ray burst afterglow spectra may reveal the progenitor evolution of the exploding Wolf-Rayet star. While the quoted paper deals with Wolf-Rayet stars which evolved through a red supergiant stage,

  3. Loop-induced dark matter direct detection signals from gamma-ray lines

    DEFF Research Database (Denmark)

    Frandsen, Mads Toudal; Haisch, Ulrich; Kahlhoefer, Felix

    2012-01-01

    Improved limits as well as tentative claims for dark matter annihilation into gamma-ray lines have been presented recently. We study the direct detection cross section induced from dark matter annihilation into two photons in a model-independent fashion, assuming no additional couplings between...... dark matter and nuclei. We find a striking non-standard recoil spectrum due to different destructively interfering contributions to the dark matter nucleus scattering cross section. While in the case of s-wave annihilation the current sensitivity of direct detection experiments is insufficient...... to compete with indirect detection searches, for p-wave annihilation the constraints from direct searches are comparable. This will allow to test dark matter scenarios with p-wave annihilation that predict a large di-photon annihilation cross section in the next generation of experiments....

  4. Recent results on celestial gamma radiation from SMM

    Science.gov (United States)

    Share, Gerald H.

    1991-01-01

    Observations made by the Gamma Ray Spectrometer on board the SMM are described. Recent results reported include observations and analyses of gamma-ray lines from Co-56 produced in supernovae, observations of the temporal variation of the 511 keV line observed during Galactic center transits, and measurements of the diffuse Galactic spectrum from 0.3 to 8.5 MeV. The work in progress includes measurements of the distribution of Galactic Al-26, observations to place limits on Galactic Ti-44 and Fe-60 and on Be-7 produced in novae, and searches for a characteristic gamma-ray emission from pair plasmas, a 2.223 MeV line emission, limits on deexcitation lines from interstellar C and O, and gamma-ray bursts.

  5. Initial studies of the gamma resonance of the 109mAg isomer with a gravitational gamma spectrometer

    International Nuclear Information System (INIS)

    Alpatov, V. G.; Bayukov, Yu. D.; Davydov, A. V.; Isaev, Yu. N.; Kartashov, G. R.; Korotkov, M. M.; Migachev, V. V.

    2008-01-01

    The problem of observing the Moessbauer resonance absorption of gamma rays from long-lived isomers is briefly outlined, first and foremost for 109m Ag taken as an example. Experiments indicative of a small broadening of the Moessbauer gamma line of this isomer in metallic silver are described. This circumstance made it possible to develop and manufacture a gravitational gamma spectrometer and to perform the first experiments with it, which confirm once again the previous data on a small width of the gamma line in question. The broadening factor obtained from these data proved to be 6.3 -1.9 +5.2 .

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-06-07

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

  7. Calculation of gamma ray dose buildup factors in water for isotropic point, plane mono directional and line sources using MCNP code

    International Nuclear Information System (INIS)

    Atak, H.; Celikten, O. S.; Tombakoglu, M.

    2009-01-01

    Gamma ray dose buildup factors in water for isotropic point, plane mono directional and infinite/finite line sources were calculated using the MCNP code. The buildup factors are determined for gamma ray energies of 1, 2, 3 and 4 Mev and for shield thicknesses of 1, 2, 4 and 7 mean free paths. The calculated buildup factors were then fitted in the Taylor and Berger forms. For the line sources a buildup factor table was also constructed using the Sievert function and the constants in Taylor form derived in this study to compare with the Monte Carlo results. All buildup factors were compared with the tabulated data given in literature. In order to reduce the statistical errors on buildup factors, 'forced collision' option was used in the MCNP calculations.

  8. Application of PNA-technique for the measurement of multi-phase flow

    International Nuclear Information System (INIS)

    Loevhoeiden, G.; Andersen, E.; Garder, K.; Rambaek, J.P.

    1986-09-01

    The pulsed neutron activation (PNA) technique is proposed for multi-phase flow monitoring of hydrocarbons. The reactions 12 C(n,p) 12 B and 12 C(n,n') 12 C both yeld 4.4 MeV in the form of gamma radiation as a measure of carbon content. Intensity measurement of the 4.4 MeV gamma line gives a measure of the carbon content in the irradiation zone. By use of a pulsed neutron source, an estimation of the carbon content time variation is possible. In the presence of sulphur in petroleum, the reaction 34 S(n,p) 34 P offers a better possibility for flow rate determination

  9. A modular multi-microcomputer system for on-line vibration diagnostics

    International Nuclear Information System (INIS)

    Saedtler, E.

    1988-01-01

    A new modular multi-microprocessor system for on-line vibration monitoring and diagnostics of PWRs is described. The aim of the system is to make feasible an early detection of increasing failures in relevant regions of a reactor plant, to verify the mechanical integrity of the investigated components, and to improve therefore the operational safety of the plant. After a discussion of the implemented surveillance methods and algorithms, which are based on hierarchical structured identification (estimation) and statistical pattern recognition tools, the system architecture (software and hardware) is portrayed. The classification scheme itself works sequential so that samples (or features) can arrive on-line. This on-line classification is important in order to take necessary actions in time. Furthermore, the system has learning capabilities, which means it is adaptable to different, varying states and plant conditions. The main features of the system are presented and its contribution to an automation of complex surveillance and monitoring tasks is shown. (author)

  10. HIV multi-drug resistance at first-line antiretroviral failure and subsequent virological response in Asia

    OpenAIRE

    Jiamsakul, Awachana; Sungkanuparph, Somnuek; Law, Matthew; Kantor, Rami; Praparattanapan, Jutarat; Li, Patrick CK; Phanuphak, Praphan; Merati, Tuti; Ratanasuwan, Winai; Lee, Christopher KC; Ditangco, Rossana; Mustafa, Mahiran; Singtoroj, Thida; Kiertiburanakul, Sasisopin

    2014-01-01

    Introduction: First-line antiretroviral therapy (ART) failure often results from the development of resistance-associated mutations (RAMs). Three patterns, including thymidine analogue mutations (TAMs), 69 Insertion (69Ins) and the Q151M complex, are associated with resistance to multiple-nucleoside reverse transcriptase inhibitors (NRTIs) and may compromise treatment options for second-line ART. Methods: We investigated patterns and factors associated with multi-NRTI RAMs at first-line failu...

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

    International Nuclear Information System (INIS)

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

    1985-01-01

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

  12. Gamma spectrometry and plastic-scintillator inherent background

    International Nuclear Information System (INIS)

    Pomerantsev, V.V.; Gagauz, I.B.; Mitsai, L.I.; Pilipenko, V.S.; Solomonov, V.M.; Chernikov, V.V.; Tsirlin, Y.A.

    1988-01-01

    The authors measured the energy resolution for a linear dependence of light yield on gamma radiation energy of gamma spectrometers based on plastic scintillation detectors for several plastic scintillators. If there were several gamma lines from the source the line with the highest energy was used to eliminate distortion due to overlap from the Compton background from gamma radiation of higher energy. Attenuation lengths were calculated. The tests were based on three modes of interaction between the gamma radiation and the scintillator: Compton scattering, the photoelectric effect, and pair formation. The contribution from light collection was also considered. The scintillators tested included polystyrene, polymethyl methacrylate, cesium iodide, and sodium iodide. Gamma sources included cesium 137, sodium 22, potassium 40, yttrium 88, thorium 232, and plutonium-beryllium

  13. Microwave-gamma ray water in crude monitor

    International Nuclear Information System (INIS)

    Paap, H.J.

    1984-01-01

    A microwave-gamma ray water-in-crude monitoring system measures the percent quantity of fresh water or salt water in crude oil flowing in a pipe line. The system includes a measuring cell arranged with the pipe line so that the crude oil flows through the measuring cell. A microwave transmitter subsystem and a gamma ray source are arranged with the measuring cell so that microwave energy and gamma rays are transmitted through the measuring cell. A microwave receiving subsystem and a gamma ray detector provide signals corresponding to received microwave energy and to the received gamma rays, respectively. Apparatus connected to the microwave receiver and to the gamma ray detector provides an indication of the percentage of water in the crude oil

  14. 2015 In-Situ Gamma-Ray Assay of the West Cell Line in the 235-F Plutonium Fuel Form Facility

    Energy Technology Data Exchange (ETDEWEB)

    Brand, A. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Aucott, T. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); DiPrete, D. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-02-01

    In November and December 2015, scientists from SRNL took a series of in-situ gamma-ray measurements through the windows in front of Cells 6-9 on the west line of the PuFF facility using a shielded, 120% high-purity germanium detector. The detector efficiency was estimated using a combination of MCNP simulations and empirical measurements. Where possible, the distribution of the Pu-238 in the cells was determined using the Germanium Gamma-ray Imager (GeGI). This distribution was then fed into the MCNP model to quantify the Pu-238 in each cell. Data analysis was performed using three gamma rays emitted by Pu-238 (99.85 keV, 152.7 keV, and 766.4 keV) providing three independent estimates of the mass of Pu-238 holdup in each of the cells.

  15. Multi-parameter study of gammas capture

    International Nuclear Information System (INIS)

    Samama, R.; Nifenecker, H.; Carlos, P.; Delaitre, B.

    1966-06-01

    This equipment is intended for analyzing, recording, and reading simultaneous information from several 'gamma' detectors. It allows multiparameter study of γ-γ cascades emitted after thermal neutrons capture. (authors) [fr

  16. On-line gas mixing and multi-channel distribution system

    International Nuclear Information System (INIS)

    Kalmani, S.D.; Mondal, N.K.; Satyanarayana, B.; Verma, P.; Joshi, Avinash

    2009-01-01

    In this presentation, we describe a mass-flow controller based on-line gas mixing unit with the multi-channel distribution system. We highlight different aspects such as requirement, design, calibration, control and operation of this system. This unit has the capability to mix up to four different input gases and distribute over 16 output channels. Output in individual channels is controlled accurately by using capillary-based system. At present, we are using this gas mixing unit for prototype of iron calorimeter (ICAL) detector of India-based Neutrino Observatory (INO).

  17. Multi-Band Light Curves from Two-Dimensional Simulations of Gamma-Ray Burst Afterglows

    Science.gov (United States)

    MacFadyen, Andrew

    2010-01-01

    The dynamics of gamma-ray burst outflows is inherently multi-dimensional. 1.) We present high resolution two-dimensional relativistic hydrodynamics simulations of GRBs in the afterglow phase using adaptive mesh refinement (AMR). Using standard synchrotron radiation models, we compute multi-band light curves, from the radio to X-ray, directly from the 2D hydrodynamics simulation data. We will present on-axis light curves for both constant density and wind media. We will also present off-axis light curves relevant for searches for orphan afterglows. We find that jet breaks are smoothed due to both off-axis viewing and wind media effects. 2.) Non-thermal radiation mechanisms in GRB afterglows require substantial magnetic field strengths. In turbulence driven by shear instabilities in relativistic magnetized gas, we demonstrate that magnetic field is naturally amplified to half a percent of the total energy (epsilon B = 0.005). We will show high resolution three dimensional relativistic MHD simulations of this process as well as particle in cell (PIC) simulations of mildly relativistic collisionless shocks.

  18. Gamma-ray burst spectra

    International Nuclear Information System (INIS)

    Teegarden, B.J.

    1982-01-01

    A review of recent results in gamma-ray burst spectroscopy is given. Particular attention is paid to the recent discovery of emission and absorption features in the burst spectra. These lines represent the strongest evidence to date that gamma-ray bursts originate on or near neutron stars. Line parameters give information on the temperature, magnetic field and possibly the gravitational potential of the neutron star. The behavior of the continuum spectrum is also discussed. A remarkably good fit to nearly all bursts is obtained with a thermal-bremsstrahlung-like continuum. Significant evolution is observed of both the continuum and line features within most events

  19. Gamma-Ray Imaging Spectrometer (GRIS): a new balloon-borne experiment for gamma-ray line astronomy

    International Nuclear Information System (INIS)

    Teegarden, B.J.; Cline, T.L.; Gehrels, N.; Porreca, G.; Tueller, J.; Leventhal, M.; Huters, A.F.; Maccallum, C.J.; Stang, P.D.; Sandia Labs., Albuquerque, NM)

    1985-01-01

    High resolution gamma-ray spectroscopy is a relatively new field that holds great promise for further understanding of high energy astrophysical processes. When the high resolution gamma-ray spectrometer (GRSE) was removed from the GRO payload, a balloon program was initiated to permit continued development and improvement of instrumentation in this field, as well as continued scientific observations. The Gamma-Ray Imaging Spectrometer (GRIS) is one of the experiments selected as part of this program. The instrument contains a number of new and innovative features that are expected to produce a significant improvement in source location accuracy and sensitivity over previous balloon and satellite experiments

  20. Survey of potential use of dynamic line phantom for quality control of Gamma camera

    International Nuclear Information System (INIS)

    Trindev, P.; Ozturk, N.

    2004-01-01

    Different phantoms, used to evaluate the essential for image quality parameters of gamma cameras in order to avoid artefacts, are presented. The prices are significant and it is a sensible approach to optimise the type and number of phantoms necessary for quality control. Among all phantoms the price of 'Dynamic Line Phantom' (DLP) is impressive, but it is announced to substitute several 'passive' and 'active' phantoms. The goal of this paper is to justify this statement. The programs, based on image profile are discussed in the paper and the practical uses of the different programs are given

  1. The Gamma-Ray Emitting Radio-Loud Narrow-Line Seyfert 1 Galaxy PKS 2004-447 II. The Radio View

    Science.gov (United States)

    Schulz, R.; Kreikenbohm, A.; Kadler, M.; Ojha, R.; Ros, E.; Stevens, J.; Edwards, P. G.; Carpenter, B.; Elsaesser, D.; Gehrels, N.; hide

    2016-01-01

    Context. gamma-ray-detected radio-loud narrow-line Seyfert 1 (gamma-NLS1) galaxies constitute a small but interesting sample of the gamma-ray-loud AGN. The radio-loudest gamma-NLS1 known, PKS2004447, is located in the southern hemisphere and is monitored in the radio regime by the multiwavelength monitoring programme TANAMI. Aims. We aim for the first detailed study of the radio morphology and long-term radio spectral evolution of PKS2004447, which are essential for understanding the diversity of the radio properties of gamma-NLS1s. Methods. The TANAMI VLBI monitoring program uses the Australian Long Baseline Array (LBA) and telescopes in Antarctica, Chile, New Zealand, and South Africa to monitor the jets of radio-loud active galaxies in the southern hemisphere. Lower resolution radio flux density measurements at multiple radio frequencies over four years of observations were obtained with the Australia Telescope Compact Array (ATCA). Results. The TANAMI VLBI image at 8.4GHz shows an extended one-sided jet with a dominant compact VLBI core. Its brightness temperature is consistent with equipartition, but it is an order of magnitude below other gamma-NLS1s with the sample value varying over two orders of magnitude. We find a compact morphology with a projected large-scale size 11 kpc and a persistent steep radio spectrum with moderate flux-density variability. Conclusions. PKS2004447 appears to be a unique member of the gamma-NLS1 sample. It exhibits blazar-like features, such as a flat featureless X-ray spectrum and a core-dominated, one-sided parsec-scale jet with indications for relativistic beaming. However, the data also reveal properties atypical for blazars, such as a radio spectrum and large-scale size consistent with compact-steep-spectrum (CSS) objects, which are usually associated with young radio sources. These characteristics are unique among all gamma-NLS1s and extremely rare among gamma-ray-loud AGN.

  2. Correction of Doppler broadening of {gamma}-ray lines induced by particle emission in heavy-ion induced fusion-evaporation reactions

    Energy Technology Data Exchange (ETDEWEB)

    Nyberg, J; Seweryniak, D; Fahlander, C; Insua-Cao, P [Uppsala Univ. (Sweden). Dept. of Radiation Sciences; Johnson, A; Cederwall, B [Manne Siegbahn Inst. of Physics, Stockholm (Sweden); [Royal Inst. of Tech., Stockholm (Sweden); Adamides, E; Piiparinen, M [National Centre for Scientific Research, Ag. Paraskevi, Attiki (Greece); Atac, A; Norlin, L O [Niels Bohr Inst., Copenhagen (Denmark); Ideguchi, E; Mitarai, S [Kyushu Univ., Fukuoka (Japan). Dept. of Physics; Julin, R; Juutinen, S; Tormanen, S; Virtanen, A [Jyvaeskylae Univ. (Finland). Dept. of Physics; Karczmarczyk, W; Kownacki, J [Warsaw Univ. (Poland); Schubart, R [Hahn-Meitner-Institut Berlin GmbH (Germany)

    1992-08-01

    The effect of particle emission on the peak shape of {gamma}-ray lines have been investigated using the NORDBALL detector system. By detecting neutrons, protons and {alpha} particles emitted in the {sup 32}S (95 MeV) + {sup 27}Al reaction, the energy and direction of emission of the residual nuclei could be determined and subsequently used for an event-by -event Doppler correction of the detected {gamma} rays. Extensive Monte Carlo simulations were performed to study how the different Doppler phenomena influence the peak shape and in particular which particle detector properties are important for the Doppler correction. (author). 2 refs., 1 tab., 4 figs.

  3. An automatic gain matching method for {gamma}-ray spectra obtained with a multi-detector array

    Energy Technology Data Exchange (ETDEWEB)

    Pattabiraman, N.S.; Chintalapudi, S.N.; Ghugre, S.S. E-mail: ssg@alpha.iuc.res.in

    2004-07-01

    The increasing size of data sets from large multi-detector arrays makes the traditional approach to the pre-evaluation of the data difficult and time consuming. The pre-sorting involves detection and correction of the observed on-line drifts followed by calibration of the raw data. A new method for automatic detection and correction of these instrumental drifts is presented. An application of this method to the data acquired using a multi-Clover array is discussed.

  4. On-line monitoring of fermentation processes using multi-wavelength fluorescence

    DEFF Research Database (Denmark)

    Odman, Peter; Petersen, Nanna; Johansen, Claus Lindvald

    2007-01-01

    . The model system considered in this work is the antibiotic production by Streptomyces coelicolor, a filamentous bacterium. In addition to predicting concentrations of biomass in the fermentation broth, the data allowed detection of different physiological states, i.e. growth phase and phosphate limitation......Fermentation processes often suffer from a lack of real-time methods for on-line determination of variables like the concentrations of nutrients and products. This work aims at investigating the possibilities of implementing an on-line fermentation monitoring system based on multi......-wavelength fluorescence (MWF). This type of sensor has previously showed promising accuracy and selectivity for in situ monitoring of cell mass and certain metabolites in bioreactors (Lantz et al., 2006). The sensor generates multivariate data outputs, which necessitate chemometric modeling for signal interpretation...

  5. Development and application of gamma scanning technology for on-line investigation of industrial process columns and vessels

    International Nuclear Information System (INIS)

    Jaafar Abdullah

    1999-01-01

    Plant Assessment Technology (PAT) group, in association with Intelligent System (IS) Group and Engineering Services Department of Malaysian Institute for Nuclear Technology Research (MINT) has developed gamma scanning facilities for on-line investigation of industrial process columns and vessels. The technology, based on the principle of gamma-ray absorption, has been successfully applied for troubleshooting of a number of distillation columns and process vessels in petroleum refineries, gas processing plants and chemical plants in the country and the region. This paper outlines basic characteristics of the system and describes the inspection procedures, and in addition, case studies are also presented. The case studies are purposely chosen to illustrate the versatility of the technology, and furthermore to demonstrate the economic benefits which can be realised from the application of this technology. (author)

  6. Cosmical sources of gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kuchowicz, B [Warsaw Univ. (Poland)

    1974-01-01

    A brief historical outline of the X-ray and ..gamma..-ray astronomies is given first, then a summary of the recent status of X-ray astronomy follows. Further chapters include information on ..gamma..-ray sources in the solar system, in our Galaxy, and beyond it. In discussing linear gamma spectra attention is paid to the possibility of studying explosive nucleo-synthesis by observation of gamma lines from supernova remnants, etc. Questions of the isotropic gamma background are discussed at the end of the survey.

  7. Approximate Analysis of Multi-State Weighted k-Out-of-n Systems Applied to Transmission Lines

    Directory of Open Access Journals (Sweden)

    Xiaogang Song

    2017-10-01

    Full Text Available Multi-state weighted k-out-of-n systems are widely applied in various scenarios, such as multiple line (power/oil transmission line transmission systems where the capability of fault tolerance is desirable. However, the complex operating environment and the dynamic features of load demands influence the evaluation of system reliability. In this paper, a stochastic multiple-valued (SMV approach is proposed to efficiently predict the reliability of two models of systems with non-repairable components and dynamically repairable components. The weights/performances and reliabilities of multi-state components (MSCs are represented by stochastic sequences consisting of a fixed number of multi-state values with the positions being randomly permutated. Using stochastic sequences with L multiple values, linear computational complexities with parameters n and L are required by the SMV approach to compute the reliability of different multi-state k-out-of-n systems at a reasonable accuracy, compared to the complexities of universal generating functions (UGF and fuzzy universal generating functions (FUGF that increase exponentially with the value of n. The analysis of two benchmarks shows that the proposed SMV approach is more efficient than the analysis using UGF or FUGF.

  8. Use of a multi-channel {gamma} spectrometer for quantitative measurements in radio-protection; Utilisation d'un spectrometre {gamma} multicanaux en vue de mesures quantitatives appliquees a la radio protection

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-07-01

    The author stresses the advantages, in radio-protection, of using {gamma} spectrometry for analysis of radioelements. He describes a simple and rapid method for dosing several radioelements in one sample. With a view to measuring the sources used for the calibration of detectors, the author shows how it is possible to determine the photon flux at one given point and to deduce from it the intensity of the irradiation due to each {gamma} line. The sensitivity and the accuracy of the measurements are discussed. (author) [French] L'autour rappelle l'interet que presente, en radioprotection, la spectrometrie {gamma} pour l'analyse des radioelements. Il expose une methode simple et rapide permettant de doser plusieurs radioelements dans un meme echantillon. Envisageant la dosimetrie des sources utilisees pour l'etalonnage des detecteurs, l'auteur montre comment l'on peut determiner le flux de photons en un point considere et en deduire l'intensite d'irradiation associee a chaque raie {gamma}. La sensibilite et la precision des mesures sont discutees. (auteur)

  9. Design innovations in neutron and gamma detectors

    International Nuclear Information System (INIS)

    Prasad, K.R.

    2003-01-01

    Neutron and gamma radiation needs to be monitored in most nuclear installations since it is highly penetrating. On-line monitoring of these radiations is very important for the safe and controlled operation of nuclear reactors, accelerators etc. Several design innovations have been carried out on gas ionisation detectors such as boron-lined proportional counters and ion chambers, fission detectors, gamma ion chambers as well as self-powered detectors. The use of additional structures within boron-lined detectors has enhanced their neutron sensitivity without a corresponding increase in the unwanted gamma sensitivity. The neutron sensitivity of fission counters can be enhanced by designing them as transmission line devices. Ion chambers with two and six pairs of electrodes have been developed for monitoring pulsed x-ray background at accelerator areas. Ion chambers have been employed at gamma fields up to 80 kR/h by deriving the exposure levels on-line using microcontroller devices programmed on the basis of theoretical and empirical formulas. The use of gas electron multiplier foils is proposed for charge multiplication in ion chambers. Self-powered detectors with new emitter materials like Hi, Ni and Inconel have been developed. (author)

  10. MO-FG-CAMPUS-JeP1-01: Prompt Gamma Imaging with a Multi-Knife-Edge Slit Collimator: Evaluation for Use in Proton Beam Range Verification

    Energy Technology Data Exchange (ETDEWEB)

    Ready, J [UC Berkeley, Berkeley, CA (United States); Negut, V; Mihailescu, L [Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Vetter, K [UC Berkeley, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Berkeley, CA (United States)

    2016-06-15

    Purpose: To evaluate and characterize a multi-slit collimated imaging system for use in prompt gamma range verification of proton therapy. Methods: Acrylic (PMMA) targets were irradiated with a 50 MeV proton beam. With the collimator placed 13 cm from the beam axis, photons of energy from 2–7 MeV were measured. Image reconstruction provided 2-dimensional distribution of gamma rays. Estimated Bragg peak location was compared with 1-dimensional profiles of photon images. Shifts in Bragg peak were simulated by physically moving the targets in 1 mm increments. Results: The imaging system measured prompt gamma emissions resulting from a 50 MeV proton beam, at currents up to 2 nA, incident on a PMMA target. Overall system detection efficiency was approximately 2.6×10{sup −5} gamma/proton. With delivery of 1×10{sup 11} protons, shifts of 1 mm in the target location were detected in 2D prompt gamma images and 1D profiles. With delivery of 1×10{sup 8} protons, shifts of approximately 3 mm were detectable. Conclusion: This work has characterized the performance of a prototype multi-slit collimated imaging system. The system can produce 2D images of prompt gamma distributions and detect shifts in Bragg peak location down to 1 mm. These results encourage further development and optimization of the system for clinical proton beam applications. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number: DENA0000979 through the Nuclear Science and Security Consortium.

  11. Standardization of radionuclides multi-gamma emitters 166mHo and 72Ga and determination of its gamma intensities by decay

    International Nuclear Information System (INIS)

    Moreira, Denise Simoes

    2005-01-01

    In the present work, the multi-gamma emitters 166m Ho and 72 Ga have been measured by 4πβ-γ coincidence technique. The calibration system is composed of a 4π gas-flow proportional counter coupled to a pair of NaI(Tl) crystals. Both radionuclides were measured by using two gamma discrimination windows, namely (629.9 + 834.2) keV and (2201.6 + 2507.7) keV for 72 Ga and 184.4 keV and (711.7 + 830.5) keV for 166m Ho. The methodology recently developed by LMN (Laboratorio de Metrologia Nuclear) for simulating all detection processes in a 4π(β,X)-γ coincidence system by means of the Monte Carlo technique was applied to the measurements of both radionuclides, and the predict behavior extrapolation curve was compared with the experimental data. The results obtained were in good agreement within the experimental uncertainty. The emission probabilities per decay of the most intense y-ray in the decay of 166m Ho and 72 Ga were measured by means HPGe spectrometer system, which was previously calibrated with standard sources of 57 Co, 60 Co, 54 Mn, 133 Ba, 24 Na, 152E u and 241 Am previously standardized in the 4πβ-γ system. All the uncertainties evolved were treated rigorously, by means of covariance analysis. (author)

  12. FLARE-LIKE VARIABILITY OF THE Mg II {lambda}2800 EMISSION LINE IN THE {gamma}-RAY BLAZAR 3C 454.3

    Energy Technology Data Exchange (ETDEWEB)

    Leon-Tavares, J. [Finnish Centre for Astronomy with ESO (FINCA), University of Turku, Vaeisaelaentie 20, FI-21500 Piikkioe (Finland); Chavushyan, V.; Patino-Alvarez, V.; Carraminana, A.; Carrasco, L. [Instituto Nacional de Astrofisica Optica y Electronica (INAOE), Apartado Postal 51 y 216, 72000 Puebla (Mexico); Valtaoja, E. [Tuorla Observatory, Department of Physics and Astronomy, University of Turku, FI-20100 Turku (Finland); Arshakian, T. G. [I. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, D-50937 Koeln (Germany); Popovic, L. C. [Astronomical Observatory, Volgina 7, 11160 Belgrade 74 (Serbia); Tornikoski, M.; Laehteenmaeki, A. [Aalto University Metsaehovi Radio Observatory, Metsaehovintie 114, FI-02540 Kylmaelae (Finland); Lobanov, A. [Max-Planck-Institut fuer Radioastronomie, Auf dem Huegel 69, D-53121 Bonn (Germany)

    2013-02-01

    We report the detection of a statistically significant flare-like event in the Mg II {lambda}2800 emission line of 3C 454.3 during the outburst of autumn 2010. The highest levels of emission line flux recorded over the monitoring period (2008-2011) coincide with a superluminal jet component traversing through the radio core. This finding crucially links the broad emission line fluctuations to the non-thermal continuum emission produced by relativistically moving material in the jet and hence to the presence of broad-line region clouds surrounding the radio core. If the radio core were located at several parsecs from the central black hole, then our results would suggest the presence of broad-line region material outside the inner parsec where the canonical broad-line region is envisaged to be located. We briefly discuss the implications of broad emission line material ionized by non-thermal continuum in the context of virial black hole mass estimates and gamma-ray production mechanisms.

  13. Multi-particle Emission from $^{31}$Ar at ISOLDE

    CERN Document Server

    Marroquin, I; Ciemny, A A; de Witte, H; Fraile, L M; Fynbo, H O U; Garzón-Camacho, A; Howard, A; Johansson, H; Jonson, B; Kirsebom, O S; Koldste, G T; Lica, R; Lund, M V; Madurga, M; Mazzocchi, C; Mihai, C; Munch, M; Nae, S A; Nacher, E; Negret, A; Nilsson, T; Perea, A; Refsgaard, J; Riisager, K; Rapisarda, E; Sotty, C; Stanoiu, M; Tengblad, O; Turturica, A E; Vedia, M V

    2016-01-01

    A multi-particle decay experiment was successfully performed at the ISOLDE Decay Station. In this new permanent station, devoted to\\break $\\beta$-decay studies, the novel MAGISOL Si-Plugin Chamber was installed to study the exotic decay modes of the proton drip-line nucleus ${^{31}}$Ar. The motivation was to search for $\\beta3p$ and $\\beta3p\\gamma$ channels, as well as to provide information on resonances in ${^{30}}$S and ${^{29}}$P relevant for the astrophysical\\break rp-process. Description of the experimental set-up and preliminary results are presented.

  14. Multi-scale Clustering of Points Synthetically Considering Lines and Polygons Distribution

    Directory of Open Access Journals (Sweden)

    YU Li

    2015-10-01

    Full Text Available Considering the complexity and discontinuity of spatial data distribution, a clustering algorithm of points was proposed. To accurately identify and express the spatial correlation among points,lines and polygons, a Voronoi diagram that is generated by all spatial features is introduced. According to the distribution characteristics of point's position, an area threshold used to control clustering granularity was calculated. Meanwhile, judging scale convergence by constant area threshold, the algorithm classifies spatial features based on multi-scale, with an O(n log n running time.Results indicate that spatial scale converges self-adaptively according with distribution of points.Without the custom parameters, the algorithm capable to discover arbitrary shape clusters which be bound by lines and polygons, and is robust for outliers.

  15. Human Cells as Platform to Produce Gamma-Carboxylated Proteins.

    Science.gov (United States)

    de Sousa Bomfim, Aline; de Freitas, Marcela Cristina Corrêa; Covas, Dimas Tadeu; de Sousa Russo, Elisa Maria

    2018-01-01

    The gamma-carboxylated proteins belong to a family of proteins that depend on vitamin K for normal biosynthesis. The major representative gamma-carboxylated proteins are the coagulation system proteins, for example, factor VII, factor IX, factor X, prothrombin, and proteins C, S, and Z. These molecules have harbored posttranslational modifications, such as glycosylation and gamma-carboxylation, and for this reason they need to be produced in mammalian cell lines. Human cells lines have emerged as the most promising alternative to the production of gamma-carboxylated proteins. In this chapter, the methods to generate human cells as a platform to produce gamma-carboxylated proteins, for example the coagulation factors VII and IX, are presented. From the cell line modification up to the vitamin K adaptation of the produced cells is described in the protocols presented in this chapter.

  16. Muon Beam Studies in the H4 beam line and the Gamma Irradiation Facility (GIF++)

    CERN Document Server

    Margraf, Rachel; CERN. Geneva. ATS Department

    2018-01-01

    In this note, we present detailed simulation results for the trajectory of a muon beam, traversing beam zones PPE-134 and PPE-154, produced by a 150 GeV positive hadron beam incident on collimators 9 & 10 in the H4 beam line when these collimators are placed off-beam axis to stop all hadrons and electrons. Using G4Beamline, a GEANT-4 based Monte-Carlo program, the trajectory of the muon beam has been studied for several field strengths of the GOLIATH magnet, as well as for different polarities. The position of the beam at the Gamma Irradiation Facility (GIF++), located downstream the PPE-144 area, is also presented. In addition, two configurations of the two XTDV’s present in the line (XTDV.022.520 and XTDV.022.610) have been studied, with the purpose to simulate the pion contamination of the beam both in PPE134 and GIF++.

  17. Hybrid MWPC gamma ray detecting system for applications in nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, J E; Connolly, J F [Science Research Council, Chilton (UK). Rutherford Lab.

    1978-10-15

    Results are presented from prototype MWPC gas-solid hybrid imaging detectors designed for applications in nuclear medicine. Using a multi-section chamber with foil converter cathodes and a delay line readout technique, the authors have made a sup(99m)Tc imaging detector with a spatial resolution of 5 mm fwhm and a projected quantum efficiency of 15% for a full scale device. With lead foil cathodes the detector design yields similar spatial resolution and quantum efficiency when positron annihilation gammas are detected. Images of positron emitters (/sup 22/Na and /sup 68/Ga) are presented.

  18. Whole-procedure clinical accuracy of Gamma Knife treatments of large lesions

    International Nuclear Information System (INIS)

    Ma Lijun; Chuang, Cynthia; Descovich, Martina; Petti, Paula; Smith, Vernon; Verhey, Lynn

    2008-01-01

    The mechanical accuracy of Gamma Knife radiosurgery based on single-isocenter measurement has been established to within 0.3 mm. However, the full delivery accuracy for Gamma Knife treatments of large lesions has only been estimated via the quadrature-sum analysis. In this study, the authors directly measured the whole-procedure accuracy for Gamma Knife treatments of large lesions to examine the validity of such estimation. The measurements were conducted on a head-phantom simulating the whole treatment procedure that included frame placement, computed tomography imaging, treatment planning, and treatment delivery. The results of the measurements were compared with the dose calculations from the treatment planning system. Average agreements of 0.1-1.6 mm for the isodose lines ranging from 25% to 90% of the maximum dose were found despite potentially large contributing uncertainties such as 3-mm imaging resolution, 2-mm dose grid size, 1-mm frame registration, multi-isocenter deliveries, etc. The results of our measurements were found to be significantly smaller (>50%) than the calculated value based on the quadrature-sum analysis. In conclusion, Gamma Knife treatments of large lesions can be delivered much more accurately than predicted from the quadrature-sum analysis of major sources of uncertainties from each step of the delivery chain.

  19. Inspection logistics planning for multi-stage production systems with applications to semiconductor fabrication lines

    Science.gov (United States)

    Chen, Kyle Dakai

    Since the market for semiconductor products has become more lucrative and competitive, research into improving yields for semiconductor fabrication lines has lately received a tremendous amount of attention. One of the most critical tasks in achieving such yield improvements is to plan the in-line inspection sampling efficiently so that any potential yield problems can be detected early and eliminated quickly. We formulate a multi-stage inspection planning model based on configurations in actual semiconductor fabrication lines, specifically taking into account both the capacity constraint and the congestion effects at the inspection station. We propose a new mixed First-Come-First-Serve (FCFS) and Last-Come-First-Serve (LCFS) discipline for serving the inspection samples to expedite the detection of potential yield problems. Employing this mixed FCFS and LCFS discipline, we derive approximate expressions for the queueing delays in yield problem detection time and develop near-optimal algorithms to obtain the inspection logistics planning policies. We also investigate the queueing performance with this mixed type of service discipline under different assumptions and configurations. In addition, we conduct numerical tests and generate managerial insights based on input data from actual semiconductor fabrication lines. To the best of our knowledge, this research is novel in developing, for the first time in the literature, near-optimal results for inspection logistics planning in multi-stage production systems with congestion effects explicitly considered.

  20. Evaluate The Fluctuation Of Phytic Acid Content In Seed From Mutant Lines By Gamma Ray

    International Nuclear Information System (INIS)

    Nguyen Thi Lang; Pham Van Ut

    2011-01-01

    Phytic acid is a molecule composed of myo-inositol 1,2,3,4,5,6 hexakis dihydrogen phosphate (Ins P6), a major component in the source of phosphorus (P) reserves of about 50 plants - 80% of total seed phosphorus (Lott, 1984). At physiological pH in the form of phytic acid have negatively charged ions hold together the complex mineral nutrition creates indigestion. Moreover, phosphorus in the form of phytate or phytic humans and monogastric animals can not absorb, are all discharged polluted environment transitions. In rice OM819, OM4900, OM3536, D4 and D8 are irradiated with gamma rays at 5 doses: 100, 200, 300, 400 and 500 Gy to create mutant strains with low levels of phytic acid. Results in radiation levels may appear 100 Gy line grain phytic acid expression is low. At the level 200 Gy of radiation is three populations OM819, OM4900 and OM3536 with 8 lines for grain phytic acid expression is low. At 300 Gy extent, appeared seven lines with low nuclear expression of phytic acid 4 populations OM819, OM4900, OM3536 and D4. At the level 400 Gy of radiation there are 4 populations appear only 5 lines expressed low phytic acid, with 3-line expression levels 3 and 2 lines with level 4 expression. At the level of radiation 500 Gy only one line appears at level 3 of phytic acid this is OM819 populations. For genotype analysis using marker RM 261 with 66.67% of the rice low phytic acid content of the expression analysis of biochemical polymorphisms. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1989-02-01

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

  2. ROLE OF LINE-OF-SIGHT COSMIC-RAY INTERACTIONS IN FORMING THE SPECTRA OF DISTANT BLAZARS IN TeV GAMMA RAYS AND HIGH-ENERGY NEUTRINOS

    International Nuclear Information System (INIS)

    Essey, Warren; Kusenko, Alexander; Kalashev, Oleg; Beacom, John F.

    2011-01-01

    Active galactic nuclei (AGNs) can produce both gamma rays and cosmic rays. The observed high-energy gamma-ray signals from distant blazars may be dominated by secondary gamma rays produced along the line of sight by the interactions of cosmic-ray protons with background photons. This explains the surprisingly low attenuation observed for distant blazars, because the production of secondary gamma rays occurs, on average, much closer to Earth than the distance to the source. Thus, the observed spectrum in the TeV range does not depend on the intrinsic gamma-ray spectrum, while it depends on the output of the source in cosmic rays. We apply this hypothesis to a number of sources and, in every case, we obtain an excellent fit, strengthening the interpretation of the observed spectra as being due to secondary gamma rays. We explore the ramifications of this interpretation for limits on the extragalactic background light and for the production of cosmic rays in AGNs. We also make predictions for the neutrino signals, which can help probe the acceleration of cosmic rays in AGNs.

  3. SMM observations of gamma-ray transients. 3: A search for a broadened, redshifted positron annihilation line from the direction of the Galactic center

    Science.gov (United States)

    Harris, Michael J.; Share, Gerald H.; Leising, Mark D.

    1994-01-01

    We have searched for 1980-1988 Solar Maximum Mission gamma-ray spectrometer data for transient emission on timescales from hours to approximately 12 days of broad gamma-ray lines at energies approximately 400 keV, which were reported by the High Energy Astronomy Observatory (HEAO) 1 and SIGMA experiments from two sources lying toward the Galactic center. The lines have been interpreted as the product of the annihilation of positrons in pair plasmas surrounding the black hole candidate 1E 1740.7-2942 and the X-ray binary 1H 1822-371. Our results from a combined exposure of approximately 1.5 x 10(exp 7)s provide no convincing evidence for transient emission of this line on any timescale between approximately 9 hr and approximately 1 yr. Our 3 sigma upper limits on the line flux during approximately 12 day intervals are characteristically 4.8 x 10(exp -3) photon/sq cm/s, while for approximately 1 day intervals our 3 sigma upper limits are characteristically 4.9 x 10(exp -3) photon/sq cm/s. These results imply a duty cycle of less than 1.3% for the transient line measured from 1H 1822-371 during a approximately 3 week interval in 1977 by HEAO 1, and a duty cycle of less than or = 0.8% for the transient line detected in 1990 and 1992 from 1E 1740.7-2942 on approximately 1 day timescales by SIGMA.

  4. Correlative Spectral Analysis of Gamma-Ray Bursts using Swift-BAT and GLAST-GBM

    International Nuclear Information System (INIS)

    Stamatikos, Michael; Sakamoto, Taka; Band, David L.

    2008-01-01

    We discuss the preliminary results of spectral analysis simulations involving anticipated correlated multi-wavelength observations of gamma-ray bursts (GRBs) using Swift's Burst Alert Telescope (BAT) and the Gamma-Ray Large Area Space Telescope's (GLAST) Burst Monitor (GLAST-GBM), resulting in joint spectral fits, including characteristic photon energy (E peak ) values, for a conservative annual estimate of ∼30 GRBs. The addition of BAT's spectral response will (i) complement in-orbit calibration efforts of GBM's detector response matrices, (ii) augment GLAST's low energy sensitivity by increasing the ∼20-100 keV effective area, (iii) facilitate ground-based follow-up efforts of GLAST GRBs by increasing GBM's source localization precision, and (iv) help identify a subset of non-triggered GRBs discovered via off-line GBM data analysis. Such multi-wavelength correlative analyses, which have been demonstrated by successful joint-spectral fits of Swift-BAT GRBs with other higher energy detectors such as Konus-WIND and Suzaku-WAM, would enable the study of broad-band spectral and temporal evolution of prompt GRB emission over three energy decades, thus potentially increasing science return without placing additional demands upon mission resources throughout their contemporaneous orbital tenure over the next decade.

  5. Correlative Spectral Analysis of Gamma-Ray Bursts using Swift-BAT and GLAST-GBM

    International Nuclear Information System (INIS)

    Stamatikos, Michael; Sakamoto, Takanori; Band, David L.

    2008-01-01

    We discuss the preliminary results of spectral analysis simulations involving anticipated correlated multi-wavelength observations of gamma-ray bursts (GRBs) using Swift's Burst Alert Telescope (BAT) and the Gamma-Ray Large Area Space Telescope's (GLAST) Burst Monitor (GLAST-GBM), resulting in joint spectral fits, including characteristic photon energy (E peak ) values, for a conservative annual estimate of ∼30 GRBs. The addition of BAT/s spectral response will (i) complement in-orbit calibration efforts of GBM's detector response matrices, (ii) augment GLAST's low energy sensitivity by increasing the ∼20-100 keV effective area, (iii) facilitate ground-based follow-up efforts of GLAST GRBs by increasing GBM's source localization precision, and (iv) help identify a subset of non-triggered GRBs discovered via off-line GBM data analysis. Such multi-wavelength correlative analyses, which have been demonstrated by successful joint-spectral fits of Swift-BAT GRBs with other higher energy detectors such as Konus-WIND and Suzaku-WAM, would enable the study of broad-band spectral and temporal evolution of prompt GRB emission over three energy decades, thus potentially increasing science return without placing additional demands upon mission resources throughout their contemporaneous orbital tenure over the next decade

  6. Multi-band Microwave Antennas and Devices based on Generalized Negative-Refractive-Index Transmission Lines

    Science.gov (United States)

    Ryan, Colan Graeme Matthew

    Focused on the quad-band generalized negative-refractive-index transmission line (G-NRI-TL), this thesis presents a variety of novel printed G-NRI-TL multi-band microwave device and antenna prototypes. A dual-band coupled-line coupler, an all-pass G-NRI-TL bridged-T circuit, a dual-band metamaterial leaky-wave antenna, and a multi-band G-NRI-TL resonant antenna are all new developments resulting from this research. In addition, to continue the theme of multi-band components, negative-refractive-index transmission lines are used to create a dual-band circularly polarized transparent patch antenna and a two-element wideband decoupled meander antenna system. High coupling over two independently-specified frequency bands is the hallmark of the G-NRI-TL coupler: it is 0.35lambda0 long but achieves approximately -3 dB coupling over both bands with a maximum insertion loss of 1 dB. This represents greater design flexibility than conventional coupled-line couplers and less loss than subsequent G-NRI-TL couplers. The single-ended bridged-T G-NRI-TL offers a metamaterial unit cell with an all-pass magnitude response up to 8 GHz, while still preserving the quad-band phase response of the original circuit. It is shown how the all-pass response leads to wider bandwidths and improved matching in quad-band inverters, power dividers, and hybrid couplers. The dual-band metamaterial leaky-wave antenna presented here was the first to be reported in the literature, and it allows broadside radiation at both 2 GHz and 6 GHz without experiencing the broadside stopband common to conventional periodic antennas. Likewise, the G-NRI-TL resonant antenna is the first reported instance of such a device, achieving quad-band operation between 2.5 GHz and 5.6 GHz, with a minimum radiation efficiency of 80%. Negative-refractive-index transmission line loading is applied to two devices: an NRI-TL meander antenna achieves a measured 52% impedance bandwidth, while a square patch antenna incorporates

  7. Gamma-ray relative energy response of Ce: YAG crystal

    International Nuclear Information System (INIS)

    Zhang Jianhua; Zhang Chuanfei; Hu Mengchun; Peng Taiping; Wang Zhentong; Tang Dengpan; Zhao Guangjun

    2010-01-01

    Gamma-ray relative energy response of Ce: YAG crystal, which is important for pulsed γ-ray measurement, was studied in this work.The Ce: YAG crystal, which was developed at Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, was aligned point by point with γ-rays scattered from an industrial 60 Co line source. The γ-ray relative energy response was calculated using the mass attenuation coefficient. The results show that the numerical calculation method of γ-ray relative energy response is reliable, and the experimental method with multi-energy point γ-ray by Compton scattering is also feasible, that can be used for checking up correctness of the numerical calculation results. (authors)

  8. Gamma spectrometry today

    International Nuclear Information System (INIS)

    Hemingway, J.

    1990-01-01

    This paper reviews the important advances in gamma spectroscopy made in recent years. Improvements in detectors and other components and the addition of on-line computer control systems is discussed. (UK)

  9. Gamma interferon augments Fc gamma receptor-mediated dengue virus infection of human monocytic cells.

    OpenAIRE

    Kontny, U; Kurane, I; Ennis, F A

    1988-01-01

    It has been reported that anti-dengue antibodies at subneutralizing concentrations augment dengue virus infection of monocytic cells. This is due to the increased uptake of dengue virus in the form of virus-antibody complexes by cells via Fc gamma receptors. We analyzed the effects of recombinant human gamma interferon (rIFN-gamma) on dengue virus infection of human monocytic cells. U937 cells, a human monocytic cell line, were infected with dengue virus in the form of virus-antibody complexe...

  10. Multi-Stratum Networks: toward a unified model of on-line identities

    DEFF Research Database (Denmark)

    Rossi, Luca; Magnani, Matteo

    2012-01-01

    One of the reasons behind the success of Social Network Analysis is its simple and general graph model made of nodes (representing individuals) and ties. However, when we focus on our daily on-line experience we must confront a more complex scenario: people inhabitate several on-line spaces...... interacting to several communities active on various technological infrastructures like Twitter, Facebook, YouTube or FourSquare and with distinct social objectives. This constitutes a complex network of interconnected networks where users' identities are spread and where information propagates navigating...... through different communities and social platforms. In this article we introduce a model for this layered scenario that we call multi-stratum network. Through a theoretical discussion and the analysis of real-world data we show how not only focusing on a single network may provide a very partial...

  11. Energy- and time-resolved detection of prompt gamma-rays for proton range verification.

    Science.gov (United States)

    Verburg, Joost M; Riley, Kent; Bortfeld, Thomas; Seco, Joao

    2013-10-21

    In this work, we present experimental results of a novel prompt gamma-ray detector for proton beam range verification. The detection system features an actively shielded cerium-doped lanthanum(III) bromide scintillator, coupled to a digital data acquisition system. The acquisition was synchronized to the cyclotron radio frequency to separate the prompt gamma-ray signals from the later-arriving neutron-induced background. We designed the detector to provide a high energy resolution and an effective reduction of background events, enabling discrete proton-induced prompt gamma lines to be resolved. Measuring discrete prompt gamma lines has several benefits for range verification. As the discrete energies correspond to specific nuclear transitions, the magnitudes of the different gamma lines have unique correlations with the proton energy and can be directly related to nuclear reaction cross sections. The quantification of discrete gamma lines also enables elemental analysis of tissue in the beam path, providing a better prediction of prompt gamma-ray yields. We present the results of experiments in which a water phantom was irradiated with proton pencil-beams in a clinical proton therapy gantry. A slit collimator was used to collimate the prompt gamma-rays, and measurements were performed at 27 positions along the path of proton beams with ranges of 9, 16 and 23 g cm(-2) in water. The magnitudes of discrete gamma lines at 4.44, 5.2 and 6.13 MeV were quantified. The prompt gamma lines were found to be clearly resolved in dimensions of energy and time, and had a reproducible correlation with the proton depth-dose curve. We conclude that the measurement of discrete prompt gamma-rays for in vivo range verification of clinical proton beams is feasible, and plan to further study methods and detector designs for clinical use.

  12. Gamma ray astronomy from satellites and balloons

    International Nuclear Information System (INIS)

    Schoenfelder, V.

    1986-01-01

    A survey is given of gamma ray astronomy topics presented at the Cosmic Ray Conference. The major conclusions at the Cosmic Ray Conference in the field of gamma ray astronomy are given. (1) MeV-emission of gamma-ray bursts is a common feature. Variations in duration and energy spectra from burst to burst may explain the discrepancy between the measured log N - log S dependence and the observed isotropy of bursts. (2) The gamma-ray line at 1.809 MeV from Al(26) is the first detected line from a radioactive nucleosynthesis product. In order to understand its origin it will be necessary to measure its longitude distribution in the Milky Way. (3) The indications of a gamma-ray excess found from the direction of Loop I is consistent with the picture that the bulk of cosmic rays below 100 GeV is produced in galactic supernova remnants. (4) The interpretation of the large scale distribution of gamma rays in the Milky Way is controversial. At present an extragalactic origin of the cosmic ray nuclei in the GeV-range cannot be excluded from the gamma ray data. (5) The detection of MeV-emission from Cen A is a promising step towards the interesting field of extragalactic gamma ray astronomy

  13. Recognition of facial expressions by cortical multi-scale line and edge coding

    OpenAIRE

    Sousa, R.; Rodrigues, J. M. F.; du Buf, J. M. H.

    2010-01-01

    Face-to-face communications between humans involve emotions, which often are unconsciously conveyed by facial expressions and body gestures. Intelligent human-machine interfaces, for example in cognitive robotics, need to recognize emotions. This paper addresses facial expressions and their neural correlates on the basis of a model of the visual cortex: the multi-scale line and edge coding. The recognition model links the cortical representation with Paul Ekman's Action Units which are relate...

  14. High-resolution gamma ray attenuation density measurements on mining exploration drill cores, including cut cores

    Science.gov (United States)

    Ross, P.-S.; Bourke, A.

    2017-01-01

    Physical property measurements are increasingly important in mining exploration. For density determinations on rocks, one method applicable on exploration drill cores relies on gamma ray attenuation. This non-destructive method is ideal because each measurement takes only 10 s, making it suitable for high-resolution logging. However calibration has been problematic. In this paper we present new empirical, site-specific correction equations for whole NQ and BQ cores. The corrections force back the gamma densities to the "true" values established by the immersion method. For the NQ core caliber, the density range extends to high values (massive pyrite, 5 g/cm3) and the correction is thought to be very robust. We also present additional empirical correction factors for cut cores which take into account the missing material. These "cut core correction factors", which are not site-specific, were established by making gamma density measurements on truncated aluminum cylinders of various residual thicknesses. Finally we show two examples of application for the Abitibi Greenstone Belt in Canada. The gamma ray attenuation measurement system is part of a multi-sensor core logger which also determines magnetic susceptibility, geochemistry and mineralogy on rock cores, and performs line-scan imaging.

  15. The use of gamma radiation in fluid flow measurements

    International Nuclear Information System (INIS)

    Tjugum, S.A.; Johansen, G.A.

    2000-01-01

    The use of gamma radiation in densitometry measurements is a well known principle. These measurements are often used in the oil industry where there is a need for finding the gas fraction of an oil/water/gas flow. The traditional gamma densitometer has a simple construction, where the measured parameter is the attenuation of a single gamma beam. High reliability, robustness and the clamp-on possibility are advantages that this type of instruments offer. More information can be found by studying how radiation is scattered and absorbed by matter. This information is needed in new multiphase flow meters. Problems to be solved in these instruments are how to find volume fractions of more than two components, how to handle different flow regimes in non-homogeneous flow, and how to do measurements independent of the salinity of the water. The new technology involves multi-energy, multi-mode and multi-sensor systems. At the University of Bergen the focus has been on how to do flow regime and salinity independent measurements by using multi-sensor and multi-mode systems. This paper gives an overview of the different techniques, and presents the latest results within this field of research at the University of Bergen. (author)

  16. Unveiling the Progenitors of Short-duration Gamma-ray Bursts

    Science.gov (United States)

    Fong, Wen-Fai

    2016-03-01

    Gamma-ray bursts (GRBs) are relativistic explosions which originate at cosmological distances, and are among the most luminous transients in the universe. Following the prompt gamma-ray emission, a fading synchrotron ``afterglow'' is detectable at lower energies. While long-duration GRBs (duration >2 sec) are linked to the deaths of massive stars, the progenitors of short-duration GRBs (duration black hole. Such merging systems are also important to understand because they are premier candidates for gravitational wave detections with current facilities and are likely sites of heavy element nucleosynthesis. The launch of NASA's Swift satellite in 2004, with its rapid multi-wavelength monitoring and localization capabilities, led to the first discoveries of short GRB afterglows and therefore robust associations to host galaxies. At a detection rate of roughly 10 events per year, the growing number of well-localized short GRBs has enabled comprehensive population studies of their afterglows and environments for the first time. In this talk, I describe my multi-wavelength observational campaign to address testable predictions for the progenitors of short GRBs. My work comprises several lines of independent evidence to demonstrate that short GRBs originate from the mergers of two compact objects, and also provides the first constraints on the explosion properties for a large sample of events. With the direct detection of gravitational waves from compact object mergers on the horizon, these studies provide necessary inputs to inform the next decade of joint electromagnetic-gravitational wave search strategies.

  17. Librarian driven analysis with graphic user interface for nuclides quantification by gamma spectra

    Energy Technology Data Exchange (ETDEWEB)

    Kondrashov, V.S. E-mail: vlkondra@cdrewu.edu; Rothenberg, S.J.; Petersone, I

    2001-09-11

    For a set of a priori given radionuclides extracted from a general nuclide data library, the authors use median estimates of the gamma-peak areas and estimates to produce a list of possible radionuclides matching gamma-ray line(s). An a priori determined list of nuclides is obtained by searching for a match with the energy information of the database. This procedure is performed in an interactive graphic mode by markers that superimpose, on the spectral data, the energy information and yields provided by a general gamma-ray data library. This library of experimental data includes approximately 17,000 gamma-energy lines related to 756 known gamma emitter radionuclides listed by ICRP.

  18. A Minor Modification of Leading Edge Discriminator Circuitry with a Delay Line for Baseline Restoration of Scintillation Detectors

    International Nuclear Information System (INIS)

    Izumi, N

    2003-01-01

    Multi-channel neutron time-of-flight detector arrays LaNSA, T-ion, Medusa, and Mandala, have been used for neutron spectroscopy in inertial confinement fusion experiments. These multi-channel neutron detector arrays consist of many identical scintillation detectors (842 ∼ 1024 channel), data acquisition electronics (discriminators, time-to digital converters, and controller). Each detector element is operated in neutron counting mode. Time-of-flight of individual detected neutrons are recorded by time to digital converters. The energy of each detected neutrons is determined from its time-of-flight. The accurate time measurement (Δt ∼ 0.5 ns) and straightforward statistical features of the data obtained with these systems provides good integrity and reliability. The elements detector used in these systems are organic scintillators coupled with photo multiplier tubes. A scintillation detector operated in particle-counting mode requires finite recovery time after each detection event. The recovery time is determined by the time responses of scintillators, photo multiplier tubes, and the dead times of following discriminators and time-to digital converters. The harsh gamma ray background environment of fast ignitor experiments requires detectors that have fast recovery times. In high intensity laser experiments (I > 10 19 W/cm 2 ), strong gamma ray bursts are produced by relativistic laser plasma interactions. Prior to the neutron signal, these strong gamma ray bursts hit the detectors and interfere with the detection of following neutron signals. In these situations, the recovery time of the system after preceding gamma ray bursts is determined mainly by the base line shift of the PMT signal (due to slower decay components of scintillators ''after glow''). Discriminators cannot detect following signal pulses until the proceeding burst decays below its threshold voltage. The base line shift caused by the after glow prolongs the recovery time of the discriminators

  19. Natural widths of atomic K and L levels, Kα X-ray lines and several KLL Auger lines

    International Nuclear Information System (INIS)

    Krause, M.O.; Oliver, J.H.

    1979-01-01

    Semi-empirical values of the natural widths of K, L 1 , L 2 , and L 3 levels, Kα 1 and Kα 2 x-ray lines, and KL 1 L 1 , KL 1 L 2 and KL 2 L 3 Auger lines for the elements 10 1 ,L 2 , L 3 ) is obtained from the relation GAMMA/sub i/=GAMMA/sub R/,i/ω/sub i/, using the theoretical radiative rate GAMMA/sub R/,i from Scofield's relativistic, relaxed Hartree-Fock calculation and the fluorescence yield ω/sub i/ from Krause's evaluation. X-ray and Auger lines widths are calculated as the sums of pertinent level widths. This tabulation of natural level and line widths is internally consistent, and is compatible with all relevant experimental and theoretical information. Present semi-empirical widths, especially those of Kα 1 and Kα 2 x-rays, are compared with measured widths. Uncertainties of semi-empirical values are estimated

  20. Characteristics of Vocal Fold Vibrations in Vocally Healthy Subjects: Analysis with Multi-Line Kymography

    Science.gov (United States)

    Yamauchi, Akihito; Imagawa, Hiroshi; Sakakibara, Ken-Ichi; Yokonishi, Hisayuki; Nito, Takaharu; Yamasoba, Tatsuya; Tayama, Niro

    2014-01-01

    Purpose: In this study, the authors aimed to analyze longitudinal data from high-speed digital images in normative subjects using multi-line kymography. Method: Vocally healthy subjects were divided into young (9 men and 17 women; M[subscript age] = 27 years) and older groups (8 men and 12 women; M[subscript age] = 73 years). From high-speed…

  1. A multi-objective approach to the assignment of stock keeping units to unidirectional picking lines

    Directory of Open Access Journals (Sweden)

    Le Roux, G. J.

    2017-05-01

    Full Text Available An order picking system in a distribution centre consisting of parallel unidirectional picking lines is considered. The objectives are to minimise the walking distance of the pickers, the largest volume of stock on a picking line over all picking lines, the number of small packages, and the total penalty incurred for late distributions. The problem is formulated as a multi-objective multiple knapsack problem that is not solvable in a realistic time. Population-based algorithms, including the artificial bee colony algorithm and the genetic algorithm, are also implemented. The results obtained from all algorithms indicate a substantial improvement on all objectives relative to historical assignments. The genetic algorithm delivers the best performance.

  2. The change of p16 gene expression in glioma cell line C6 after radiation with gamma knife

    International Nuclear Information System (INIS)

    Zhao Xingli; Zhao Conghai; Tian Yu

    2002-01-01

    Objective: T observe the change of expression of p16 gene product, P16 protein, after treated by gamma knife on glioma cell line C6. Methods: Glioma C6 cells proliferated in vitro, treated by γ-knife in dose of 5.00 and 6.22 Gy, respectively. P16 protein was detected by immunohistochemical technique and image analysis. Results: The P16 protein in glioma C6 cells was notably increased after treatment with γ knife (P < 0.01). The grey number in C6 group (control group) was 167.1 +- 6.2 and was 155.4 +- 2.0 and 124.9 +- 7.1, respectively, in 5.00 Gy and 6.22 Gy gamma knife treated group. Conclusion: It is suggests that one of the mechanisms of glioma cell C6 apoptosis induced by γ-knife radiation may be associated with activation of p16 gene and increase of P16 protein expression

  3. Search for gamma-ray transients using the SMM spectrometer

    Science.gov (United States)

    Share, G. H.; Harris, M. J.; Leising, M. D.; Messina, D. C.

    1993-01-01

    Observations for transient radiation made by the Gamma Ray Spectrometer on the SMM satellite are summarized. Spectra were obtained from 215 solar flares and 177 gamma-ray bursts. No narrow or moderately broadened lines were observed in any of the bursts. The rate of bursts is consistent with a constant over the mission but is weakly correlated with solar activity. No evidence was found for bursts of 511 keV line emission, unaccompanied by a strong continuum, at levels not less than 0.05 gamma/sq cm s for bursts lasting not more than 16 s. No evidence was found for broad features near 1 MeV from Cyg X-1, the Galactic center, or the Crab in 12-d integrations at levels not less than 0.006 gamma/sq cm s. No evidence was found for transient celestial narrow-line emission from 300 keV to 7 MeV on min-to-hrs-long time scales from 1984 to 1989.

  4. The multi-spectral line-polarization MSE system on Alcator C-Mod

    Energy Technology Data Exchange (ETDEWEB)

    Mumgaard, R. T., E-mail: mumgaard@psfc.mit.edu; Khoury, M. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Scott, S. D. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540 (United States)

    2016-11-15

    A multi-spectral line-polarization motional Stark effect (MSE-MSLP) diagnostic has been developed for the Alcator C-Mod tokamak wherein the Stokes vector is measured in multiple wavelength bands simultaneously on the same sightline to enable better polarized background subtraction. A ten-sightline, four wavelength MSE-MSLP detector system was designed, constructed, and qualified. This system consists of a high-throughput polychromator for each sightline designed to provide large étendue and precise spectral filtering in a cost-effective manner. Each polychromator utilizes four narrow bandpass interference filters and four custom large diameter avalanche photodiode detectors. Two filters collect light to the red and blue of the MSE emission spectrum while the remaining two filters collect the beam pi and sigma emission generated at the same viewing volume. The filter wavelengths are temperature tuned using custom ovens in an automated manner. All system functions are remote controllable and the system can be easily retrofitted to existing single-wavelength line-polarization MSE systems.

  5. The multi-spectral line-polarization MSE system on Alcator C-Mod

    International Nuclear Information System (INIS)

    Mumgaard, R. T.; Khoury, M.; Scott, S. D.

    2016-01-01

    A multi-spectral line-polarization motional Stark effect (MSE-MSLP) diagnostic has been developed for the Alcator C-Mod tokamak wherein the Stokes vector is measured in multiple wavelength bands simultaneously on the same sightline to enable better polarized background subtraction. A ten-sightline, four wavelength MSE-MSLP detector system was designed, constructed, and qualified. This system consists of a high-throughput polychromator for each sightline designed to provide large étendue and precise spectral filtering in a cost-effective manner. Each polychromator utilizes four narrow bandpass interference filters and four custom large diameter avalanche photodiode detectors. Two filters collect light to the red and blue of the MSE emission spectrum while the remaining two filters collect the beam pi and sigma emission generated at the same viewing volume. The filter wavelengths are temperature tuned using custom ovens in an automated manner. All system functions are remote controllable and the system can be easily retrofitted to existing single-wavelength line-polarization MSE systems.

  6. Observation of X-ray lines from a gamma-ray burst (GRB991216): evidence of moving ejecta from the progenitor.

    Science.gov (United States)

    Piro, L; Garmire, G; Garcia, M; Stratta, G; Costa, E; Feroci, M; Mészáros, P; Vietri, M; Bradt, H; Frail, D; Frontera, F; Halpern, J; Heise, J; Hurley, K; Kawai, N; Kippen, R M; Marshall, F; Murakami, T; Sokolov, V V; Takeshima, T; Yoshida, A

    2000-11-03

    We report on the discovery of two emission features observed in the x-ray spectrum of the afterglow of the gamma-ray burst (GRB) of 16 December 1999 by the Chandra X-ray Observatory. These features are identified with the Ly(alpha) line and the narrow recombination continuum by hydrogenic ions of iron at a redshift z = 1.00 +/- 0.02, providing an unambiguous measurement of the distance of a GRB. Line width and intensity imply that the progenitor of the GRB was a massive star system that ejected, before the GRB event, a quantity of iron approximately 0.01 of the mass of the sun at a velocity approximately 0.1 of the speed of light, probably by a supernova explosion.

  7. Integrated ultrasound and gamma imaging probe for medical diagnosis

    International Nuclear Information System (INIS)

    Pani, R.; Pellegrini, R.; Cinti, M. N.; Polito, C.; Orlandi, C.; Fabbri, A.; Vincentis, G. De

    2016-01-01

    In the last few years, integrated multi-modality systems have been developed, aimed at improving the accuracy of medical diagnosis correlating information from different imaging techniques. In this contest, a novel dual modality probe is proposed, based on an ultrasound detector integrated with a small field of view single photon emission gamma camera. The probe, dedicated to visualize small organs or tissues located at short depths, performs dual modality images and permits to correlate morphological and functional information. The small field of view gamma camera consists of a continuous NaI:Tl scintillation crystal coupled with two multi-anode photomultiplier tubes. Both detectors were characterized in terms of position linearity and spatial resolution performances in order to guarantee the spatial correspondence between the ultrasound and the gamma images. Finally, dual-modality images of custom phantoms are obtained highlighting the good co-registration between ultrasound and gamma images, in terms of geometry and image processing, as a consequence of calibration procedures

  8. Metal impurities profile in a 450kg multi-crystalline silicon ingot by Cold Neutron Prompt Gamma-ray Activation Analysis

    International Nuclear Information System (INIS)

    Baek, Hani; Sun, Gwang Min; Kim, Ji seok; Oh, Mok; Chung, Yong Sam; Moon, Jong Hwa; Kim, Sun Ha; Baek, Sung Yeol; Tuan, Hoang Sy Minh

    2014-01-01

    Metal impurities are harmful to multi-crystalline silicon solar cells. They reduce solar cell conversion efficiencies through increased carrier recombination. They are present as isolated point-like impurities or precipitates. This work is to study the concentration profiles of some metal impurities of the directionally solidified 450kg multi-crystalline silicon ingot grown for solar cell production. The concentration of such impurities are generally below 10 15 cm -3 , and as such cannot be detected by physical techniques such as secondary-ion-mass spectroscopy(SIMS). So, we have tried to apply Cold Neutron - Prompt Gamma ray Activation Analysis(CN-PGAA) at the HANARO reactor research. The impurity concentrations of Au, Mn, Pt, Mo of a photovoltaic grade multi-crystalline silicon ingot appear by segregation from the liquid to the solid phase in the central region of the ingot during the crystallization. In the impurities concentration of the bottom region is higher than middle region due to the solid state diffusion. Towards the top region the segregation impurities diffused, during cooling process

  9. CAMAC gamma ray scanning system

    International Nuclear Information System (INIS)

    Moss, C.E.; Pratt, J.C.; Shunk, E.R.

    1981-01-01

    A flexible gamma-ray scanning system, based on a LeCroy 3500 multichannel analyzer and CAMAC modules, is described. The system is designed for making simultaneous passive and active scans of objects of interest to nuclear safeguards. The scanner is a stepping-motor-driven carriage; the detectors, a bismuth-germanate scintillator and a high-purity germanium detector. A total of sixteen peaks in the two detector-produced spectra can be integrated simultaneously, and any scan can be viewed during data acquisition. For active scanning, the 2615-keV gamma-ray line from a 232 U source and the 4439-keV gamma-ray line from 9 Be(α,n) 12 C were selected. The system can be easily reconfigured to accommodate up to seven detectors because it is based on CAMAC modules and FORTRAN. The system is designed for field use and is easily transported. Examples of passive and active scans are presented

  10. Seed coat color, weight and eye pattern inheritance in gamma-rays induced cowpea M2-mutant line

    Directory of Open Access Journals (Sweden)

    Reda M. Gaafar

    2016-06-01

    Full Text Available Gamma radiation is a very effective tool for inducing genetic variation in characters of many plants. Black seeds of M2 mutant were obtained after exposure of an Egyptian cowpea cultivar (Kaha 1 to a low dose of gamma rays. Segregation of seed coat color, weight of 100 seeds and seed eye pattern of the black seeds of this mutant line were further examined in this study. Four colors were observed for seed coat in the M3 plants ranging from cream to reddish brown and three eye patterns were distinguished from each other. SDS–PAGE of the seed storage proteins showed 18 protein bands; five of these bands disappeared in the seeds of M3 plants compared to M2 and M0 controls while other 5 protein bands were specifically observed in seeds of M3 plants. PCR analysis using twelve ISSR primers showed 47 polymorphic and 8 unique amplicons. The eight unique amplicons were characteristic of the cream coat color and brown wide eye pattern (M03-G10 while the polymorphic bands were shared by 6 coat-color groups. A PCR fragment of 850 bp was amplified, using primer HB-12, in M3-G04 which showed high-100 seed weight. These results demonstrated the mutagenic effects of gamma rays on seed coat color, weight of 100 seeds and eye pattern of cowpea M3 mutant plants.

  11. Chemical and microbiological assessments of the multi mixture treated by gamma radiation; Avaliacao quimica e microbiologica da multimistura tratada por irradiacao gama

    Energy Technology Data Exchange (ETDEWEB)

    Goncalves, Cinthia Graciele

    2008-07-01

    In Brazil, the multi mixture have being used since the eighties as an alternative against severe infantile malnutrition of the poorest population. However, its use is still reason of controversies mainly due to: the presence of anti nutritional factors, the microbiological quality and the nutritional value. Considering the routine use of multi mixture in the region, this work aimed to evaluate samples of multi mixture were collected in the metropolitan area of the City of Belo Horizonte/MG for determining the anti nutritional factors (phytic and oxalic acids), the microbiological quality, the centesimal and mineral composition, and still the induced effect in these factors of the gamma radiation. For the analyses, the samples passed by the process of gamma irradiation at doses of: 2, 4, 6, 8 and 10 kGy and then were evaluated anti nutritional factors (phytic acid and oxalic), the microbiological quality (yeasts and molds, Salmonella, Coagulase positive Staphylococcus, Bacillus cereus, coliform to 45 deg C) to full percentage (moisture, ash, proteins, carbohydrates and lipids) and the efficiency of the method of Paramagnetic Electronic Resonance (EPR) in the detection of irradiated samples. The mineral composition of the samples was carried out by the irradiation by Neutronic Activation. The methods used were searched in literature. The obtained results suggest that the concentration of the phytic and oxalic acids can not be appropriated for the children with severe nutritional deficit and that it would be necessary additional control in their daily ingestion due to the absorption of essential minerals. In general the samples had presented acceptable microbiological quality for consumption, except by one of it. The data of the centesimal and mineral composition, in the usually recommended portions, showed lower concentration than recommended for children. Any significant alteration in phytic and oxalic acids as well as in the centesimal composition were detected

  12. The goals of gamma-ray spectroscopy in high energy astrophysics

    Science.gov (United States)

    Lingenfelter, Richard E.; Higdon, James C.; Leventhal, Marvin; Ramaty, Reuven; Woosley, Stanford E.

    1990-01-01

    The use of high resolution gamma-ray spectroscopy in astrophysics is discussed with specific attention given to the application of the Nuclear Astrophysics Explorer (NAE). The gamma-ray lines from nuclear transitions in radionucleic decay and positron annihilation permits the study of current sites, rates and models of nucleosynthesis, and galactic structure. Diffuse galactic emission is discussed, and the high-resolution observations of gamma-ray lines from discrete sites are also described. Interstellar mixing and elemental abundances can also be inferred from high-resolution gamma-ray spectroscopy of nucleosynthetic products. Compact objects can also be examined by means of gamma-ray emissions, allowing better understanding of neutron stars and the accreting black hole near the galactic center. Solar physics can also be investigated by examining such features as solar-flare particle acceleration and atmospheric abundances.

  13. Multi-isotopic gamma-ray assay system for alpha-contaminated waste

    International Nuclear Information System (INIS)

    Close, D.A.; Pratt, J.C.; Caldwell, J.T.; Kunz, W.E.; Schultz, F.J.; Haff, K.W.

    1983-01-01

    The capability of an existing segmented gamma-ray system is being expanded for the analysis of alpha-contaminated waste drums. A cursory assay of 114 transuranic waste drums of 208-l capacity has been made. Analysis of these data indicates a detection limit better than 100 nCi/g of waste for 237 Np/ 233 Pa, 239 Pu, 241 Am, 243 Am/ 239 Np, 60 Co, 125 Sb, 134 137 Cs, and 154 Eu. A pending Code of Federal Regulation (10CFR61) stipulates that the nuclear industry quantify not only its transuranic waste, but also certain beta- and gamma-ray-emitting fission products. An assay system based on gamma-ray spectroscopy is the only system that can meet this requirement for the fission products

  14. Application of Inverse Gamma Transport to Material Thickness Identification with SGRD Code

    Directory of Open Access Journals (Sweden)

    Humbert Philippe

    2017-01-01

    Full Text Available SGRD (Spectroscopy, Gamma rays, Rapid, Deterministic code is used to infer the dimensions of a one dimensional model of a shielded gamma ray source. The method is based on the simulation of the uncollided leakage current of discrete gamma lines that are produced by nuclear decay. Experimentally, the unscattered gamma lines leakage current is obtained by processing high precision gamma spectroscopy measurements. The material thicknesses are computed with SGRD using a fast ray-tracing algorithm embedded in a non-linear multidimensional iterative optimization procedure that minimizes the error metric between calculated and measured signatures. For verification, numerical results on a test problem are presented.

  15. EPR structure of the gamma irradiated alanine spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Cabral P, A; Jimenez D, H; Urena N, F; Galindo, S; Bosch, P

    1992-03-15

    In this study is shown that the broadened five-line EPR pattern of the gamma irradiated alanine possibly decomposes into a more complex pattern when the recorded spectrum is subject to an operation of deconvolution. The EPR powder spectra of gamma irradiated DL- and L-alanine with and without binders are analysed. In all recorded spectra, each observed line is resolved into an asymmetrical triplet when a Gaussian distribution of 8.2 gauss width is removed, by deconvolution, from the observed spectrum. On the other hand, from a simple fitting analysis carried out on the original data, one encounters that some calculated relations between characteristic parameters, such as intensity ratios, deviate consistently from assumed height ratios. Both, from deconvolution and fitting results, a different structure is suggested for the observed broadened five-line EPR pattern of {gamma}-irradiated powder DL- and L-alanine. (Author)

  16. Measurements of national radiation exposure rates on train lines in Tokai area

    International Nuclear Information System (INIS)

    Matsuda, Hideharu

    1996-01-01

    For data accumulation of natural radiation exposure rate derived from gamma-ray and cosmic-ray to evaluate population dose, the author measured the rate in the running vehicles of 12 JR Tokai lines, 17 Nagoya Railway lines, 4 Kinkinippon Railway lines and 1 line of Nagoya City Bus. A portable gamma spectrometer equipped with 3' in diameter x 3' NaI (Tl) scintillation detector was placed on the seat of the vehicle for measurement in the period of December, 1992-August, 1995. Gamma-ray and cosmic-ray exposure rates in air were assessed separately as reported before and expressed in Gy/h. The average exposure rate of gamma-ray in JR Tokai lines was 19.8 nGy/h and of cosmic-ray, 28.5 nGy/h, both of which were markedly varied from line to line. The average rates of gamma-and cosmic-ray were 21.6 nGy/h and 29.0 nGy/h, respectively, in Nagoya Railway lines and 20.9 nGy/h and 28.7 nGy/h, respectively, in Kinkinippon lines. In the city bus, the respective rates were 27.2 nGy/h and 27.0 nGy/h. Thus, the average rates of gamma-ray (about 20 nGy/h) and cosmic-ray (about 29 nGy/h) were not so different between JR and other private railway lines. In the bus, the former rate was slightly lower and the latter, slightly higher. However, the total rates of both rays were in the range of about 50-55 nGy/h in all vehicles examined. (H.O.)

  17. Analysis of the gamma spectra of the uranium, actinium, and thorium decay series

    International Nuclear Information System (INIS)

    Momeni, M.H.

    1981-09-01

    This report describes the identification of radionuclides in the uranium, actinium, and thorium series by analysis of gamma spectra in the energy range of 40 to 1400 keV. Energies and absolute efficiencies for each gamma line were measured by means of a high-resolution germanium detector and compared with those in the literature. A gamma spectroscopy method, which utilizes an on-line computer for deconvolution of spectra, search and identification of each line, and estimation of activity for each radionuclide, was used to analyze soil and uranium tailings, and ore

  18. Gamma camera investigations using an on-line computer system

    International Nuclear Information System (INIS)

    Vikterloef, K.J.; Beckman, K.-W.; Berne, E.; Liljenfors, B.

    1974-01-01

    A computer system for use with a gamma camera has been developed by Oerebro Regional Hospital and Nukab AB using a PDP 8/e with a 12K core memory connected to a Selektronik gamma camera. It is possible to register, without loss, pictures of high (5kcps) pulse frequency, two separate channels with identical coordinates, fast dynamic functions down to 5 pictures/second, and to perform statistical smoothing and subtraction of two separate pictures. Experience has shown these possibilities to be so valuable that one has difficulty in thinking of a scanning system without them. This applies not only to sophisticated investigations, e.g. dual isotope registration, but also in conventional scanning for avoiding false positive interpretations and increasing the precision. It is possible at relatively low cost to add a dosage planning system. (JIW)

  19. A METEOROLOGICAL RISK ASSESSMENT METHOD FOR POWER LINES BASED ON GIS AND MULTI-SENSOR INTEGRATION

    Directory of Open Access Journals (Sweden)

    Z. Lin

    2016-06-01

    Full Text Available Power lines, exposed in the natural environment, are vulnerable to various kinds of meteorological factors. Traditional research mainly deals with the influence of a single meteorological condition on the power line, which lacks of comprehensive effects evaluation and analysis of the multiple meteorological factors. In this paper, we use multiple meteorological monitoring data obtained by multi-sensors to implement the meteorological risk assessment and early warning of power lines. Firstly, we generate meteorological raster map from discrete meteorological monitoring data using spatial interpolation. Secondly, the expert scoring based analytic hierarchy process is used to compute the power line risk index of all kinds of meteorological conditions and establish the mathematical model of meteorological risk. By adopting this model in raster calculator of ArcGIS, we will have a raster map showing overall meteorological risks for power line. Finally, by overlaying the power line buffer layer to that raster map, we will get to know the exact risk index around a certain part of power line, which will provide significant guidance for power line risk management. In the experiment, based on five kinds of observation data gathered from meteorological stations in Guizhou Province of China, including wind, lightning, rain, ice, temperature, we carry on the meteorological risk analysis for the real power lines, and experimental results have proved the feasibility and validity of our proposed method.

  20. gamma. radiation of ionium

    Energy Technology Data Exchange (ETDEWEB)

    Curie, I

    1948-12-08

    Following the work of Ward (Proc Cambridge Phil Soc 35 322(1939)), the ..gamma..-radiation of ionium (from an IoTh preparation) was studied with the aid of Ta and W screens, and an aluminum counter. The screen measurements confirmed Ward's findings of two radiations, of 68 keV and of about 200 keV. The number of quanta per second of each radiation was determined with the counter, which has been calibrated on certain L lines of radium. The global quanta number of L lines of ionium was also determined. The results were as follows: 0.7 quanta ..gamma.. of 68 keV for 100 ..cap alpha..-particles; 0.2 quanta ..gamma.. of 200 keV for 100 ..cap alpha..-particles; 10 quanta L for 100 ..cap alpha..-particles. These data, which show an important internal conversion, agree with the findings of Teillac (Compt Rend 227 1227 (1948)), who investigated the ..beta..-radiation of ionium. It is the radiation 68 keV which is highly converted. On the other hand, these results do no agree with the data on the fine structure of ionium found by Rosenblum, Valadares, and Vial (Compt Rend 227 1088(1948)).

  1. Relative branching ratio of the {eta}{yields}{pi}{sup 0}{gamma}{gamma} decay channel

    Energy Technology Data Exchange (ETDEWEB)

    Knecht, N.; Papandreou, Z.; Lolos, G.J.; Benslama, K.; Huber, G.M.; Li, S.; Bekrenev, V.; Briscoe, W.J.; Grosnick, D.; Isenhower, D.; Koetke, D.D.; Kozlenko, N.G.; Kruglov, S.; Manley, D.M.; Manweiler, R.; McDonald, S.; Olmsted, J.; Shafi, A.; Stanislaus, T.D.S

    2004-06-03

    The {eta}{yields}{pi}{sup 0}{gamma}{gamma} rare decay was measured at the AGS with the Crystal Ball photon spectrometer and its relative branching ratio was extracted to be B{sub 1}=(8.3{+-}2.8{+-}1.4)x10{sup -4}, based on the analysis of 3x10{sup 7} detected {eta} mesons. This leads to a lower partial width for this eta channel than past measurements and is in line with chiral perturbation theory calculations.

  2. Induced Mutation in Strawberry by Using Gamma Radiation

    International Nuclear Information System (INIS)

    Phadvibulya, Valailak; Puripanyavanich, Vichai; Pipattanawongse, Narongchai; Yeesawasdi, Voravit; Teja, Waich

    2003-12-01

    The culture of strawberry plants variety Tio ga were irradiated with gamma rays at doses of 0, 20, 40, 60, 80, 100,120 and 140 Gy. They were transferred to the MS medium supplemented with BA 0.1 mg/l. It was found that radiation dose which caused 50% lethality (LD 50 ) was 80 Gy. The survival plants were transferred to rooting medium (MS medium) and then transplanted to field for stolon production and yield investigation. Two lines with good fruit quality were obtained after selection till M 1 V 5 . They were planted for further testing. In experiment II, The culture of strawberry plants varieties Royal 20, Royal 70, SM and Dover were irradiated with gamma rays at doses of 0, 40 and 60 Gy. They were transplanted to field for stolon and yield production. Three lines from Royal 70 were obtained after selection till M 1 V 4 . In experiment III, the culture of strawberry plants varieties Royal 20, Royal 50, Royal 70, Nyoho and Selva were irradiated with gamma rays at the same doses as experiment II. Nine lines from Royal 70 and four lines from Nyoho with good characters were selected for further testing

  3. Performance of A Compact Multi-crystal High-purity Germanium Detector Array for Measuring Coincident Gamma-ray Emissions

    Energy Technology Data Exchange (ETDEWEB)

    Howard, Chris [Univ. of North Carolina, Chapel Hill, NC (United States); Triangle Univ. Nuclear Lab., Durham, NC (United States); Daigle, Stephen [Univ. of North Carolina, Chapel Hill, NC (United States); Triangle Univ. Nuclear Lab., Durham, NC (United States); Buckner, Matt [Univ. of North Carolina, Chapel Hill, NC (United States); Triangle Univ. Nuclear Lab., Durham, NC (United States); Erikson, Luke E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Runkle, Robert C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stave, Sean C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Champagne, Art [Univ. of North Carolina, Chapel Hill, NC (United States); Triangle Univ. Nuclear Lab., Durham, NC (United States); Cooper, Andrew [Univ. of North Carolina, Chapel Hill, NC (United States); Triangle Univ. Nuclear Lab., Durham, NC (United States); Downen, Lori [Univ. of North Carolina, Chapel Hill, NC (United States); Triangle Univ. Nuclear Lab., Durham, NC (United States); Glasgow, Brian D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kelly, Keegan [Univ. of North Carolina, Chapel Hill, NC (United States); Triangle Univ. Nuclear Lab., Durham, NC (United States); Sallaska, Anne [Univ. of North Carolina, Chapel Hill, NC (United States); Triangle Univ. Nuclear Lab., Durham, NC (United States)

    2015-02-18

    The Multi-sensor Airborne Radiation Survey (MARS) detector is a 14-crystal array of high-purity germanium (HPGe) detectors housed in a single cryostat. The array was used to measure the astrophysical S-factor for the 14N(p,γ)15O* reaction for several transition energies at an effective center of mass energy of 163 keV. Owing to the segmented nature of the MARS detector, the effect of gamma-ray summing was greatly reduced in comparison to past experiments which utilized large, single-crystal detectors. The new S-factor values agree within the uncertainties with the past measurements. Details of the analysis and detector performance will be presented.

  4. Performance of a compact multi-crystal high-purity germanium detector array for measuring coincident gamma-ray emissions

    Energy Technology Data Exchange (ETDEWEB)

    Howard, Chris; Daigle, Stephen; Buckner, Matt [University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 (United States); Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States); Erikson, Luke E.; Runkle, Robert C. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Stave, Sean C., E-mail: Sean.Stave@pnnl.gov [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Champagne, Arthur E.; Cooper, Andrew; Downen, Lori [University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 (United States); Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States); Glasgow, Brian D. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Kelly, Keegan; Sallaska, Anne [University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 (United States); Triangle Universities Nuclear Laboratory, Durham, NC 27708 (United States)

    2015-05-21

    The Multi-sensor Airborne Radiation Survey (MARS) detector is a 14-crystal array of high-purity germanium (HPGe) detectors housed in a single cryostat. The array was used to measure the astrophysical S-factor for the {sup 14}N(p,γ){sup 15}O{sup ⁎} reaction for several transition energies at an effective center-of-mass energy of 163 keV. Owing to the granular nature of the MARS detector, the effect of gamma-ray summing was greatly reduced in comparison to past experiments which utilized large, single-crystal detectors. The new S-factor values agree within their uncertainties with the past measurements. Details of the analysis and detector performance are presented.

  5. Comparison of gamma radiation - induced effects in two human prostate cancer cells

    International Nuclear Information System (INIS)

    Vucic, V.; Adzic, M.; Ruzdijic, S.; Radojcic, M.B. . E-mail address of corresponding author: vesnav@vin.bg.ac.yu; Vucic, V.)

    2005-01-01

    In this study, the effects of gamma radiation on two hormone refractory human prostate cancer cell lines, DU 145 and PC-3, were followed. It was shown that gamma radiation induced significant inhibition of cell proliferation and viability in dose dependent manner. Antiproliferative effects of radiation were similar in both cell lines, and more pronounced than cytotoxic effects. In addition to that, PC-3 cell line was more resistant to radiation -induced cytotoxicity. (author)

  6. Economics of gamma irradiation processing

    International Nuclear Information System (INIS)

    Tani, Toshio

    1980-01-01

    The gamma-ray irradiation business started at the Takasaki Laboratory of Japan Atomic Energy Research Institute. The irradiation facilities were constructed thereafter at various sites. The facilities must accept various types of irradiation, and must be constructed as multi-purpose facilities. The cost of irradiation consists of the cost of gamma sources, construction expense, personnel expense, management expense, and bank interest. Most of the expenses are considered to be fixed expense, and the amount of irradiation treatment decides the original costs of work. The relation between the irradiation dose and the construction expense shows the larger facility is more economical. The increase of amount of treatment reduces the original cost. The utilization efficiency becomes important when the amount of treatment and the source intensity exceed some values. The principal subjects of gamma-ray irradiation business are the sterilization of medical tools and foods for aseptic animals, the improvement of quality of plastic goods, and the irradiation of foods. Among them, the most important subject is the sterilization of medical tools. The cost of gamma irradiation per m 3 in still more expensive than that by ethylene oxide gas sterilization. However, the demand of gamma-ray irradiation is increasing. For the improvement of quality of plastic goods, electron irradiation is more favourable than the gamma irradiation. In near future, the economical balance of gamma irradiation can be achieved. (Kato, T.)

  7. On-ground detection of an electron-positron annihilation line from thunderclouds.

    Science.gov (United States)

    Umemoto, D; Tsuchiya, H; Enoto, T; Yamada, S; Yuasa, T; Kawaharada, M; Kitaguchi, T; Nakazawa, K; Kokubun, M; Kato, H; Okano, M; Tamagawa, T; Makishima, K

    2016-02-01

    Thunderclouds can produce bremsstrahlung gamma-ray emission, and sometimes even positrons. At 00:27:00 (UT) on 13 January 2012, an intense burst of gamma rays from a thundercloud was detected by the GROWTH experiment, located in Japan, facing the Sea of Japan. The event started with a sharp gamma-ray flash with a duration of gamma-ray emission lasting for ∼60 s. The spectrum of this prolonged emission reached ∼10 MeV, and contained a distinct line emission at 508±3(stat.)±5(sys.) keV, to be identified with an electron-positron annihilation line. The line was narrow within the instrumental energy resolution (∼80keV), and contained 520±50 photons which amounted to ∼10% of the total signal photons of 5340±190 detected over 0.1-10 MeV. As a result, the line equivalent width reached 280±40 keV, which implies a nontrivial result. The result suggests that a downward positron beam produced both the continuum and the line photons.

  8. Preliminary results of a neutron-gamma coincidence experiment

    International Nuclear Information System (INIS)

    Piercey, R.B.; Dunnam, F.E.; Muga, M.L.; Rester, A.C.; Ramayya, A.V.; Hamilton, J.H.; Eberth, J.; Zganjar, E.F.

    1984-01-01

    The recently completed neutron multiplicity detector dubbed PANDA (Pentagonal Annular Neutron Detector Array) is fully described later in this report. The new detector was recently used for the first time on-line at the Holifield Heavy Ion Research Facility to measure neutron-gamma coincidence in the 24 Mg( 58 Ni,xαypzn) reaction. The detector configuration for the experiment is shown. The PANDA was situated in the forward direction, coaxial to the beam line with five gamma-ray detectors placed at +/- 90 0 , +/- 135 0 , and 0 0 . 2 figures

  9. Gamma-Ray imaging for nuclear security and safety: Towards 3-D gamma-ray vision

    Science.gov (United States)

    Vetter, Kai; Barnowksi, Ross; Haefner, Andrew; Joshi, Tenzing H. Y.; Pavlovsky, Ryan; Quiter, Brian J.

    2018-01-01

    The development of portable gamma-ray imaging instruments in combination with the recent advances in sensor and related computer vision technologies enable unprecedented capabilities in the detection, localization, and mapping of radiological and nuclear materials in complex environments relevant for nuclear security and safety. Though multi-modal imaging has been established in medicine and biomedical imaging for some time, the potential of multi-modal data fusion for radiological localization and mapping problems in complex indoor and outdoor environments remains to be explored in detail. In contrast to the well-defined settings in medical or biological imaging associated with small field-of-view and well-constrained extension of the radiation field, in many radiological search and mapping scenarios, the radiation fields are not constrained and objects and sources are not necessarily known prior to the measurement. The ability to fuse radiological with contextual or scene data in three dimensions, in analog to radiological and functional imaging with anatomical fusion in medicine, provides new capabilities enhancing image clarity, context, quantitative estimates, and visualization of the data products. We have developed new means to register and fuse gamma-ray imaging with contextual data from portable or moving platforms. These developments enhance detection and mapping capabilities as well as provide unprecedented visualization of complex radiation fields, moving us one step closer to the realization of gamma-ray vision in three dimensions.

  10. SU-E-T-563: Multi-Fraction Stereotactic Radiosurgery with Extend System of Gamma Knife: Treatment Verification Using Indigenously Designed Patient Simulating Multipurpose Phantom

    Energy Technology Data Exchange (ETDEWEB)

    Bisht, R; Kale, S; Gopishankar, N; Rath, G; Julka, P; Agarwal, D; Singh, M; Garg, A; Kumar, P; Thulkar, S; Sharma, B [All India Institute of Medical Sciences, New Delhi (India)

    2015-06-15

    Purpose: Aim of the study is to evaluate mechanical and radiological accuracy of multi-fraction regimen and validate Gamma knife based fractionation using newly developed patient simulating multipurpose phantom. Methods: A patient simulating phantom was designed to verify fractionated treatments with extend system (ES) of Gamma Knife however it could be used to validate other radiotherapy procedures as well. The phantom has options to insert various density material plugs and mini CT/MR distortion phantoms to analyze the quality of stereotactic imaging. An additional thorax part designed to predict surface doses at various organ sites. The phantom was positioned using vacuum head cushion and patient control unit for imaging and treatment. The repositioning check tool (RCT) was used to predict phantom positioning under ES assembly. The phantom with special inserts for film in axial, coronal and sagittal plane were scanned with X-Ray CT and the acquired images were transferred to treatment planning system (LGP 10.1). The focal precession test was performed with 4mm collimator and an experimental plan of four 16mm collimator shots was prepared for treatment verification of multi-fraction regimen. The prescription dose of 5Gy per fraction was delivered in four fractions. Each fraction was analyzed using EBT3 films scanned with EPSON 10000XL Scanner. Results: The measurement of 38 RCT points showed an overall positional accuracy of 0.28mm. The mean deviation of 0.28% and 0.31 % were calculated as CT and MR image distortion respectively. The radiological focus accuracy test showed its deviation from mechanical center point of 0.22mm. The profile measurement showed close agreement between TPS planned and film measured dose. At tolerance criteria of 1%/1mm gamma index analysis showed a pass rate of > 95%. Conclusion: Our results show that the newly developed multipurpose patient simulating phantom is highly suitable for the verification of fractionated stereotactic

  11. Comparison of GAMMA results with experimental data in the naturally circulating gas loop

    International Nuclear Information System (INIS)

    Lee, J.I.; No, H.C.

    2009-01-01

    Natural circulation steady-state data with carbon dioxide and nitrogen are compared to numerical predictions by GAMMA code, which is being developed by KAIST and KAERI. The GAMMA code is a computational tool for predicting various transients those can potentially occur in a high temperature gas cooled reactor. The code has a capability of analyzing multi-dimensional multi-component mixture and includes models for friction, heat transfer, chemical reaction and multi-component molecular diffusion. Natural circulation data with nitrogen and carbon dioxide gases show that the loop operates in a Deteriorated Turbulent Heat Transfer (DTHT) regime which exhibits substantially reduced heat transfer coefficients. The GAMMA code with original heat transfer package predicted conservative results in terms of peak wall temperature. Also, the estimated peak location did not successfully match with the data. Even though GAMMA's original heat transfer package included mixed-convection regime, which is part of DTHT regime, still the results showed that the original heat transfer package performs with insufficient accuracy. After implementing a recently developed correlation and corresponding heat transfer regime map into GAMMA to cover the whole range of deteriorated heat transfer, a better agreement with data was obtained. In addition, RELAP5-MOD3 results are discussed in parallel. (author)

  12. Determining the solar-flare photospheric scale height from SMM gamma-ray measurements

    Science.gov (United States)

    Lingenfelter, Richard E.

    1991-01-01

    A connected series of Monte Carlo programs was developed to make systematic calculations of the energy, temporal and angular dependences of the gamma-ray line and neutron emission resulting from such accelerated ion interactions. Comparing the results of these calculations with the Solar Maximum Mission/Gamma Ray Spectrometer (SMM/GRS) measurements of gamma-ray line and neutron fluxes, the total number and energy spectrum of the flare-accelerated ions trapped on magnetic loops at the Sun were determined and the angular distribution, pitch angle scattering, and mirroring of the ions on loop fields were constrained. Comparing the calculations with measurements of the time dependence of the neutron capture line emission, a determination of the He-3/H ratio in the photosphere was also made. The diagnostic capabilities of the SMM/GRS measurements were extended by developing a new technique to directly determine the effective photospheric scale height in solar flares from the neutron capture gamma-ray line measurements, and critically test current atmospheric models in the flare region.

  13. EPR investigation of some gamma-irradiated medicines

    International Nuclear Information System (INIS)

    Aleksieva, Katerina; Yordanov, Nicola

    2016-01-01

    The results of EPR studies on three medical tablets – Galanthamine, Cytisine and Tribulus terrestris before and after gamma-irradiation are reported. Before irradiation Galanthamine and Cytisine tablets are EPR silent, whereas Tribulus terrestris show a broad singlet line with g factor 2.2084±0.002. The same spectrum is recorded after irradiation. After gamma-sterilization, however, Galanthamine and Cytisine tablets exhibit a typical EPR spectrum due to gamma induced free radicals in lactose used as an excipient. These stable free radicals can be used for identification of radiation processing for a long time after it. Key words: medical tablets, gamma-irradiation, EPR

  14. Operations manual for the megachannel gamma-ray coincidence system

    International Nuclear Information System (INIS)

    Ruhter, W.

    1977-01-01

    To aid in the study of nuclear structures, a megachannel pulse-height coincidence analysis system on a PDP-8 computer was constructed. The system digitizes the energies of coincident gamma-rays and stores the resultant information on a moving-head disk. The system uses a minicomputer to sort and store gamma-gamma coincident information on line. The megachannel system and how to use it are described

  15. Growth and viability of Aedes albopictus cell line in vitro after cesium-137 gamma irradiation

    International Nuclear Information System (INIS)

    Blakely, E.A.

    1975-01-01

    The radiosensitivity of the cultured mosquito cell line Aedes albopictus (Skuse) was investigated. Population growth was followed by total cell counts and by viable cell counts on aliquots of cultures exposed to various doses of gamma radiation during exponential growth. Viable cell determinations were based on the cellular exclusion of the dye, alcian blue, in a procedure adapted to the insect cells in culture. Viability determinations in the irradiated exponential cultures indicated that initially there was some increase in the gestation, suggesting that gonadal steroids may have unusual effects on uterine physiology and biochemistry in this species. Consequently, studies were undertaken to elucidate some of the basic responses of hamster uteri to estradiol benzoate and progesterone under conditions of protein malnutrition, actinomycin D administration and corticosterone injection. Furthermore, the effects of gonadal steroids on uteri of pregnant ovariectomized hamsters were studied

  16. Nature of gamma rays background radiation in new and old buildings of Qatar University

    International Nuclear Information System (INIS)

    Al-Houty, L.; Abou-Leila, H.; El-Kameesy, S.

    1987-01-01

    Measurements and analysis of gamma-background radiation spectrum in four different places of Qatar University campus were performed at the energy range 10 keV-3 MeV using hyper pure Ge-detector. The dependence of the detector absolute photopeak efficiency on gamma-ray energies was determined and correction of the data for that was also done. The absorbed dose for each gamma line was calculated and an estimation of the total absorbed dose for the detected gamma lines in the four different places was obtained. Comparison with other results was also performed

  17. Combination of e+/e- ratio from AMS-02 and gamma ray line from Fermi-LAT with implication for Dark Matter

    OpenAIRE

    Li, Shiyuan; Luo, Yonggang

    2013-01-01

    The precise AMS-02 data provide definite information for the e+/e- ratio in 100 - 350 GeV region. Assuming that the recent gamma ray line observed by Fermi-LAT experiment is product of dark matter in space and taken as input. We make a global fit for the AMS-02 e+/e- spectrum with both dark matter and pulsar contribution. For this spectrum over 130 GeV, pulsar is the dominant contribution. We also investigate the constrains on hadron production from dark matter annihilation.

  18. Neutron and gamma-ray transmission technique for the on-line determination of moisture in coal and coke

    International Nuclear Information System (INIS)

    Sowerby, B.D.; Millen, M.J.; Rafter, P.T.

    1985-01-01

    A fast neutron and gamma-ray transmission technique is being developed for the on-line analysis of moisture in coal and coke. The technique utilises 252 Cf and 137 Cs sources and 3 He and NaI(Tl) detectors. Laboratory measurements on single coal samples have shown that moisture can be determined to better than 1 wt% over the range 0 to 16 wt% moisture and 5 to 17cm thickness. Reduced errors were obtained for restricted ranges of moisture and thickness. Preliminary measurements on coke of thickness 30 to 50cm have shown that moisture can be determined to within 0.26 wt% over the range 1 to 16 wt% moisture

  19. Radio jets and gamma-ray emission in radio-silent narrow-line Seyfert 1 galaxies

    Science.gov (United States)

    Lähteenmäki, A.; Järvelä, E.; Ramakrishnan, V.; Tornikoski, M.; Tammi, J.; Vera, R. J. C.; Chamani, W.

    2018-06-01

    We have detected six narrow-line Seyfert 1 (NLS1) galaxies at 37 GHz that were previously classified as radio silent and two that were classified as radio quiet. These detections reveal the presumption that NLS1 galaxies labelled radio quiet or radio silent and hosted by spiral galaxies are unable to launch jets to be incorrect. The detections are a plausible indicator of the presence of a powerful, most likely relativistic jet because this intensity of emission at 37 GHz cannot be explained by, for example, radiation from supernova remnants. Additionally, one of the detected NLS1 galaxies is a newly discovered source of gamma rays and three others are candidates for future detections. 37 GHz data are only available in electronic form at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/614/L1

  20. The optimization of gamma spectra processing in prompt gamma neutron activation analysis (PGNAA)

    Energy Technology Data Exchange (ETDEWEB)

    Pinault, Jean-Louis [IAEA Expert, 96 rue du Port David, 45370 Dry (France)], E-mail: jeanlouis_pinault@hotmail.fr; Solis, Jose [Instituto Peruano de Energia Nuclear, Av. Canada No. 1470, San Borja, Lima 41 (Peru)

    2009-04-15

    The uncertainty of the elemental analysis is one of the major factors governing the utility of on-line Prompt Gamma Neutron Activation Analysis (PGNAA) in the blending and sorting of bulk materials. In this paper, a general method applicable to Gamma spectra processing is presented and applied to PGNAA in mineral industry. Based on the Fourier transform of spectra and their de-correlation in the Fourier space (the improvement of the conditioning of the correlation matrix), processing of overlapping of characteristic peaks minimizes the propagation of random errors, which optimizes the accuracy and decreases the detection limits of elemental analyses. In comparison with classical methods based on the linear combinations of relevant regions of spectra the improvement may be considerable, especially when several elements are interfering. The method is applied to four case stories covering both borehole logging and on-line analysis on conveyor belt of raw materials.

  1. Scintillation counter, maximum gamma aspect

    International Nuclear Information System (INIS)

    Thumim, A.D.

    1975-01-01

    A scintillation counter, particularly for counting gamma ray photons, includes a massive lead radiation shield surrounding a sample-receiving zone. The shield is disassembleable into a plurality of segments to allow facile installation and removal of a photomultiplier tube assembly, the segments being so constructed as to prevent straight-line access of external radiation through the shield into radiation-responsive areas. Provisions are made for accurately aligning the photomultiplier tube with respect to one or more sample-transmitting bores extending through the shield to the sample receiving zone. A sample elevator, used in transporting samples into the zone, is designed to provide a maximum gamma-receiving aspect to maximize the gamma detecting efficiency. (U.S.)

  2. Airborne gamma-ray survey around the Negoro fault. 1; Negoro danso shuhen chiiki ni okeru kuchu {gamma} sen tansa. 1

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, E.; Kasuya, Y.; Hasegawa, H. [Aero Asahi Corp., Tokyo (Japan); Tsukuda, E. [Geological Survey of Japan, Tsukuba (Japan)

    1997-05-27

    An airborne gamma-ray survey was carried out to investigate the active fault system in the central structure line in the peripheral area of the city of Wakayama. At the same time, with an objective to enhance applicability of the airborne gamma-ray survey to active fault investigation, fundamental data were acquired and discussed. The measurement data were processed according to the standard method specified by IAEA. An ID-FFT filter and a nonlinear filter were employed to extract anomalous gamma-ray intensity values. The gamma-ray intensity distribution chart shows a noticeable positive anomalous area extending from the central part of the western edge to the north-east direction. This area agrees nearly well with the Negoro fault, but its peak portion is positioned slightly more to south than the position of the Negoro fault shown in existing data. The Sakuraike fault and the vicinity of the central structure line also show positive anomaly as a whole, particularly remarkably in the vicinity of their converging portion. However, differing from the vicinity of the Negoro fault, the areas are not extracted as an anomalous area which has directionality and extends in a line form. One of the factors for this would be that it is a fault in unsolidified deposits with low opening trend, differing from the one in solidified rocks. 1 fig., 3 tabs.

  3. Tables of nuclear constants for gamma activation analysis

    International Nuclear Information System (INIS)

    Randa, Z.; Kreisinger, F.

    1980-01-01

    The tables of photonuclear reactions presented, designed for gamma activation analysis, list accurate data on energy of photons emitted by radionuclides, gamma line intensity, half-lives, photonuclear reactions, or the genetic relationship leading to the formation of the given radionuclide together with the respective reaction thresholds. They also list natural isotopic occurrence of the individual target nuclides. The tables are arranged by increasing atomic numbers of newly formed radionuclides and by increasing gamma energies. (B.S.)

  4. Neutron-induced 2.2 MeV background in gamma ray telescopes

    International Nuclear Information System (INIS)

    Zanrosso, E.M.; Long, J.L.; Zych, A.D.; White, R.S.; Hughes Aircraft Co., Los Angeles, CA)

    1985-01-01

    Neutron-induced gamma ray production is an important source of background in Compton scatter gamma ray telescopes where organic scintillator material is used. Most important is deuteron formation when atmospheric albedo and locally produced neutrons are thermalized and subsequently absorbed in the hydrogenous material. The resulting 2.2 MeV gamma line essentially represents a continuous isotropic source within the scintillator itself. Interestingly, using a scintillator material with a high hydrogen-to-carbon ratio to minimize the neutron-induced 4.4 MeV carbon line favors the np reaction. The full problem of neutron-induced background in Compton scatter telescopes has been previously discussed. Results are presented of observations with the University of California balloon-borne Compton scatter telescope where the 2.2 MeV induced line emission is prominently seen

  5. Effects of irradiation on the expression of the adhesion molecules (NCAM, ICAM-1) by glioma cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Yamanaka, Ryuya; Tanaka, Ryuichi; Yoshida, Seiichi [Niigata Univ. (Japan). Brain Research Inst.

    1993-11-01

    The expression of the intercellular adhesion molecule-1 (ICAM-1) and neural cell adhesion molecule (NCAM) by glioma cell lines was investigated. The effects of interferon (IFN)-[gamma] or irradiation on the expression was also assessed. Two glioma cell lines showed more than 75% NCAM-positive cells. After treatment with IFN-[gamma] or irradiation, another three cell lines were induced to show more than 50% positive cells. Three glioma cell lines showed more than 50% ICAM-1-positive cells. After treatment with IFN-[gamma], another two cell lines were induced to show more than 50% positive cells. After treatment with irradiation, one more cell line was induced to show more than 50% positive cells. ICAM-1 and NCAM expression by glioma cell lines is susceptible to modulation by IFN-[gamma] or irradiation. (author).

  6. Neural network consistent empirical physical formula construction for neutron–gamma discrimination in gamma ray tracking

    International Nuclear Information System (INIS)

    Yildiz, Nihat; Akkoyun, Serkan

    2013-01-01

    Highlights: ► Detector responses in neutron–gamma discrimination were estimated by neural networks. ► Novel consistent neural network empirical physical formulas (EPFs) were constructed for detector responses. ► The EPFs are of explicit mathematical functional form. ► The EPFs can be used to derive various physical functions relevant to neutron–gamma discrimination in gamma ray tracking. -- Abstract: Gamma ray tracking is an efficient detection technique in studying exotic nuclei which lies far from beta stability line. To achieve very powerful and extraordinary resolution ability, new detectors based on gamma ray tracking are currently being developed. To reach this achievement, the neutron–gamma discrimination in these detectors is also an important task. In this paper, by suitable layered feedforward neural networks (LFNNs), we have constructed novel and consistent empirical physical formulas (EPFs) for some highly nonlinear detector counts measured in neutron–gamma discrimination. The detector counts data used in the discrimination was actually borrowed from our previous paper. The counts used here had been originally measured versus the following parameters: energy deposited in the first interaction points, difference in the incoming direction of initial gamma rays, and finally figure of merit values of the clusters determined by tracking. The LFNN–EPFs are of explicit mathematical functional form. Therefore, by various suitable operations of mathematical analysis, these LFNN–EPFs can be used to derivate further physical functions which might be potentially relevant to neutron–gamma discrimination performance of gamma ray tracking.

  7. Isolation of carrot plant lines with altered carotene contents from gamma irradiated explants

    International Nuclear Information System (INIS)

    Pawlicki, N.; Sangwan, R.S.; Sangwan-Norreel, B.S.

    2001-01-01

    Dietary vitamin A is mainly obtained from carotenes of vegetables and fruits. Carrot (Daucus carota L.) is one of the major sources of carotene. Carrot cultivars have been obtained mainly through classical breeding, and genetic selection has permitted the creation of new varieties with high carotene contents. The fact that in several crops agronomically important mutants/variants have been generated by in vitro culture techniques prompted us to combine gamma irradiation and in vitro somatic embryogenesis to obtain regenerants with variations in carotene content in carrot. To test the effect of gamma rays on somatic embryogenesis and on the carotene level, aseptically germinated seedlings of 8 carrot varieties were exposed to 5; 10 and 500 Gy before culturing petiole segments on LN1 medium. Non-irradiated petioles produced calli with somatic embryos, while irradiated explants reacted differently according to radiation dose. After 4 weeks of culture on LN1 medium, petiole segments of different varieties irradiated with 5 and 10 Gy gave more callus with embryos than those with non-irradiated segments. However, after the subculture on LN medium, the development of embryos into plantlets was rare. It was also noted that after irradiation with 5 Gy, the petiole segments gave voluminous calli. Further, in variety 'Chantenay', the irradiated calli were deep orange while non-irradiated calli were green. However, embryo formation was not observed in these calli. This orange coloration suggests an appreciable synthesis of carotene in the calli. Gamma rays, probably produced cell lines with different colors and carotene content. Of the 8 cultivars tested, normal plantlets of 3 varieties were regenerated from somatic embryos irradiated with 10 Gy, and were transferred to greenhouse to develop roots. For each assay, the carotene analysis was carried out on 2 roots, and compared with plants produced from non-irradiated somatic embryos. Carotene level in the plants, derived from

  8. Determining fast orientation changes of multi-spectral line cameras from the primary images

    Science.gov (United States)

    Wohlfeil, Jürgen

    2012-01-01

    Fast orientation changes of airborne and spaceborne line cameras cannot always be avoided. In such cases it is essential to measure them with high accuracy to ensure a good quality of the resulting imagery products. Several approaches exist to support the orientation measurement by using optical information received through the main objective/telescope. In this article an approach is proposed that allows the determination of non-systematic orientation changes between every captured line. It does not require any additional camera hardware or onboard processing capabilities but the payload images and a rough estimate of the camera's trajectory. The approach takes advantage of the typical geometry of multi-spectral line cameras with a set of linear sensor arrays for different spectral bands on the focal plane. First, homologous points are detected within the heavily distorted images of different spectral bands. With their help a connected network of geometrical correspondences can be built up. This network is used to calculate the orientation changes of the camera with the temporal and angular resolution of the camera. The approach was tested with an extensive set of aerial surveys covering a wide range of different conditions and achieved precise and reliable results.

  9. Electron and positron contributions to the displacement per atom profile in bulk multi-walled carbon nanotube material irradiated with gamma rays

    International Nuclear Information System (INIS)

    Leyva Fabelo, Antonio; Pinnera Hernandez, Ibrahin; Leyva Pernia, Diana

    2013-01-01

    The electron and positron contributions to the effective atom displacement cross-section in multi-walled carbon nanotube bulk materials exposed to gamma rays were calculated. The physical properties and the displacement threshold energy value reported in literature for this material were taken into account. Then, using the mathematical simulation of photon and particle transport in matter, the electron and positron energy flux distributions within the irradiated object were also calculated. Finally, considering both results, the atom displacement damage profiles inside the analyzed bulk carbon nanotube material were determined. The individual contribution from each type of secondary particles generated by the photon interactions was specified. An increasing behavior of the displacement cross-sections for all the studied particles energy range was observed. The particles minimum kinetic energy values that make probabilistically possible the single and multiple atom displacement processes were determined. The positrons contribution importance to the total number of point defects generated during the interaction of gamma rays with the studied materials was confirmed

  10. Neutron-induced gamma-ray spectroscopy: simulations for chemical mapping of planetary surfaces

    International Nuclear Information System (INIS)

    Brueckner, J.; Waenke, H.; Reedy, R.C.

    1986-01-01

    Cosmic rays interact with the surface of a planetary body and produce a cascade of secondary particles, such as neutrons. Neutron-induced scattering and capture reactions play an important role in the production of discrete gamma-ray lines that can be measured by a gamma-ray spectrometer on board of an orbiting spacecraft. These data can be used to determine the concentration of many elements in the surface of a planetary body, which provides clues to its bulk composition and in turn to its origin and evolution. To investigate the gamma rays made by neutron interactions, thin targets were irradiated with neutrons having energies from 14 MeV to 0.025 eV. By means of foil activation technique the ratio of epithermal to thermal neutrons was determined to be similar to that in the Moon. Gamma rays emitted by the targets and the surrounding material were detected by a high-resolution germanium detector in the energy range of 0.1 to 8 MeV. Most of the gamma-ray lines that are expected to be used for planetary gamma-ray spectroscopy were found in the recorded spectra and the principal lines in these spectra are presented. 58 refs., 7 figs., 9 tabs

  11. ADVANCED X-BAND TEST ACCELERATOR FOR HIGH BRIGHTNESS ELECTRON AND GAMMA RAY BEAMS

    Energy Technology Data Exchange (ETDEWEB)

    Marsh, R A; Anderson, S G; Barty, C P; Chu, T S; Ebbers, C A; Gibson, D J; Hartemann, F V; Adolphsen, C; Jongewaard, E N; Raubenheimer, T; Tantawi, S G; Vlieks, A E; Wang, J W

    2010-05-12

    In support of Compton scattering gamma-ray source efforts at LLNL, a multi-bunch test stand is being developed to investigate accelerator optimization for future upgrades. This test stand will enable work to explore the science and technology paths required to boost the current 10 Hz monoenergetic gamma-ray (MEGa-Ray) technology to an effective repetition rate exceeding 1 kHz, potentially increasing the average gamma-ray brightness by two orders of magnitude. Multiple bunches must be of exceedingly high quality to produce narrow-bandwidth gamma-rays. Modeling efforts will be presented, along with plans for a multi-bunch test stand at LLNL. The test stand will consist of a 5.5 cell X-band rf photoinjector, single accelerator section, and beam diagnostics. The photoinjector will be a high gradient standing wave structure, featuring a dual feed racetrack coupler. The accelerator will increase the electron energy so that the emittance can be measured using quadrupole scanning techniques. Multi-bunch diagnostics will be developed so that the beam quality can be measured and compared with theory. Design will be presented with modeling simulations, and layout plans.

  12. Distributed flow estimation and closed-loop control of an underwater vehicle with a multi-modal artificial lateral line.

    Science.gov (United States)

    DeVries, Levi; Lagor, Francis D; Lei, Hong; Tan, Xiaobo; Paley, Derek A

    2015-03-25

    Bio-inspired sensing modalities enhance the ability of autonomous vehicles to characterize and respond to their environment. This paper concerns the lateral line of cartilaginous and bony fish, which is sensitive to fluid motion and allows fish to sense oncoming flow and the presence of walls or obstacles. The lateral line consists of two types of sensing modalities: canal neuromasts measure approximate pressure gradients, whereas superficial neuromasts measure local flow velocities. By employing an artificial lateral line, the performance of underwater sensing and navigation strategies is improved in dark, cluttered, or murky environments where traditional sensing modalities may be hindered. This paper presents estimation and control strategies enabling an airfoil-shaped unmanned underwater vehicle to assimilate measurements from a bio-inspired, multi-modal artificial lateral line and estimate flow properties for feedback control. We utilize potential flow theory to model the fluid flow past a foil in a uniform flow and in the presence of an upstream obstacle. We derive theoretically justified nonlinear estimation strategies to estimate the free stream flowspeed, angle of attack, and the relative position of an upstream obstacle. The feedback control strategy uses the estimated flow properties to execute bio-inspired behaviors including rheotaxis (the tendency of fish to orient upstream) and station-holding (the tendency of fish to position behind an upstream obstacle). A robotic prototype outfitted with a multi-modal artificial lateral line composed of ionic polymer metal composite and embedded pressure sensors experimentally demonstrates the distributed flow sensing and closed-loop control strategies.

  13. Over-expression of bacterial gamma-glutamylcysteine synthetase (GSH1) in plastids affects photosynthesis, growth and sulphur metabolism in poplar (Populus tremula x Populus alba) dependent on the resulting gamma-glutamylcysteine and glutathione levels.

    Science.gov (United States)

    Herschbach, Cornelia; Rizzini, Luca; Mult, Susanne; Hartmann, Tanja; Busch, Florian; Peuke, Andreas D; Kopriva, Stanislav; Ensminger, Ingo

    2010-07-01

    We compared three transgenic poplar lines over-expressing the bacterial gamma-glutamylcysteine synthetase (GSH1) targeted to plastids. Lines Lggs6 and Lggs12 have two copies, while line Lggs20 has three copies of the transgene. The three lines differ in their expression levels of the transgene and in the accumulation of gamma-glutamylcysteine (gamma-EC) and glutathione (GSH) in leaves, roots and phloem exudates. The lowest transgene expression level was observed in line Lggs6 which showed an increased growth, an enhanced rate of photosynthesis and a decreased excitation pressure (1-qP). The latter typically represents a lower reduction state of the plastoquinone pool, and thereby facilitates electron flow along the electron transport chain. Line Lggs12 showed the highest transgene expression level, highest gamma-EC accumulation in leaves and highest GSH enrichment in phloem exudates and roots. This line also exhibited a reduced growth, and after a prolonged growth of 4.5 months, symptoms of leaf injury. Decreased maximum quantum yield (F(v)/F(m)) indicated down-regulation of photosystem II reaction centre (PSII RC), which correlates with decreased PSII RC protein D1 (PsbA) and diminished light-harvesting complex (Lhcb1). Potential effects of changes in chloroplastic and cytosolic GSH contents on photosynthesis, growth and the whole-plant sulphur nutrition are discussed for each line.

  14. Using wavelet features for analyzing gamma lines

    International Nuclear Information System (INIS)

    Medhat, M.E.; Abdel-hafiez, A.; Hassan, M.F.; Ali, M.A.; Uzhinskii, V.V.

    2004-01-01

    Data processing methods for analyzing gamma ray spectra with symmetric bell-shaped peaks form are considered. In many cases the peak form is symmetrical bell shaped in particular a Gaussian case is the most often used due to many physical reasons. The problem is how to evaluate parameters of such peaks, i.e. their positions, amplitudes and also their half-widths, that is for a single peak and overlapped peaks. Through wavelet features by using Marr wavelet (Mexican Hat) as a correlation method, it could be to estimate the optimal wavelet parameters and to locate peaks in the spectrum. The performance of the proposed method and others shows a better quality of wavelet transform method

  15. Catalog of gamma-rays unplaced in radioactive decay schemes

    International Nuclear Information System (INIS)

    Narita, Tsutomu; Kitao, Kensuke.

    1991-03-01

    A catalog is made for gamma-rays emitted in decay of radioactive nuclides but not placed in their decay schemes. It consists of two tables. In Table 1, the number of these unplaced gamma-ray components by a nuclide is given together with the fraction of total intensity of these gamma-rays to that of all observed gamma-rays. In Table 2, the unplaced gamma-rays are arranged in order of increasing energy. Each line of this table contains the gamma-ray energy, intensity, nuclide identification, and energies and intensities of the most prominent gamma-rays from the decay of the radionuclides. This catalog is a compilation from Evaluated Nuclear Structure Data File (ENSDF) maintained by National Nuclear Data Center at Brookhaven National Laboratory, of at February 1990. (author)

  16. Positron imaging with multiwire proportional chamber-gamma converter hybrid detectors

    International Nuclear Information System (INIS)

    Chu, D.Y.H.

    1976-09-01

    A large area positron camera was developed using multiwire proportional chambers as detectors and electromagnetic delay lines for coordinate readout. Honeycomb structured gamma converters made of lead are coupled to the chambers for efficient gamma detection and good spatial resolution. Two opposing detectors, each having a sensitive area of 48 cm x 48 cm, are operated in coincidence for the detection of annihilation gammas (511 keV) from positron emitters. Detection efficiency of 4.2 percent per detector and spatial resolution of 6 to 7 mm FWHM at the mid-plane were achieved. The present camera operates at a maximum count rate of 24 K counts/min, limited by accidental coincidence. The theory for the gamma converter is presented along with a review of the operation of the multiwire proportional chamber and delay line readout. Calculated gamma converter efficiencies are compared with the measured results using a prototype test chamber. The characteristics of the positron camera system is evaluated, and the performance is shown to be consistent with calculation

  17. Switchable multi-wavelength erbium-doped fiber ring laser based on a tapered in-line Mach–Zehnder interferometer

    Science.gov (United States)

    Zhou, Yuxin; Wang, Xin; Tang, Zijuan; Lou, Shuqin

    2018-05-01

    In this paper, a switchable multi-wavelength erbium-doped fiber ring laser based on a tapered in-line Mach–Zehnder interferometer is proposed. The in-line Mach–Zehnder interferometer is fabricated by splicing a large-core fiber between two segments of single mode fibers, in which the first splicing point is tapered and the second splicing point is connected directly. By carefully rotating the polarization controller, switchable single-, dual-, triple- and quad-wavelength lasing outputs can be obtained with a side mode suppression ratio higher than 50 dB. The maximal peak power difference of multi-wavelength lasing is 3.67 dB, demonstrating a good power equalization performance. Furthermore, the proposed laser is proven to be very stable at room temperature. The wavelength shifts and peak power fluctuations are less than 0.02 nm and 1.3 dB over half an hour. In addition, stable quintuple-wavelength lasing with a side mode suppression ratio higher than 50 dB can also be realized when the filter length is changed.

  18. Study on Scattered Data Points Interpolation Method Based on Multi-line Structured Light

    International Nuclear Information System (INIS)

    Fan, J Y; Wang, F G; W, Y; Zhang, Y L

    2006-01-01

    Aiming at the range image obtained through multi-line structured light, a regional interpolation method is put forward in this paper. This method divides interpolation into two parts according to the memory format of the scattered data, one is interpolation of the data on the stripes, and the other is interpolation of data between the stripes. Trend interpolation method is applied to the data on the stripes, and Gauss wavelet interpolation method is applied to the data between the stripes. Experiments prove regional interpolation method feasible and practical, and it also promotes the speed and precision

  19. Off-line mapping of multi-rate dependent task sets to many-core platforms

    DEFF Research Database (Denmark)

    Puffitsch, Wolfgang; Noulard, Eric; Pagetti, Claire

    2015-01-01

    This paper presents an approach to execute safety-critical applications on multi- and many-core processors in a predictable manner. We investigate three concrete platforms: the Intel Single-chip Cloud Computer, the Texas Instruments TMS320C6678 and the Tilera TILEmpower-Gx36. We define an execution...... model to safely execute dependent periodic task sets on these platforms. The four rules of the execution model entail that an off-line mapping of the application to the platform must be computed. The paper details our approach to automatically compute a valid mapping. Furthermore, we evaluate our...

  20. U and Pu Gamma-Ray Measurements of Spent Fuel Using a Gamma-Ray Mirror Band-Pass Filter

    International Nuclear Information System (INIS)

    Ziock, K.-P.; Kisner, R.; Melin, A.; Patton, B.; Alameda, J.; Brejnhold, N.; Decker, T.; Descalle, M.-A.; Fernandez-Perea, M.; Hill, R.; Ruz Armendariz, J.; Soufli, R.

    2015-01-01

    We report the use of grazing incidence gamma-ray mirrors as narrow band-pass filters for advanced non-destructive analysis of spent nuclear fuel. The mirrors limit radiation reaching an HPGe detector to narrow spectral bands around characteristic emission lines from fissile isotopes in the fuel. Ideally, these emissions could be used to determine the fuel's fissile content, but they are normally masked by the overwhelming radiation emitted by short-lived fission by-products. These latter emissions raise the overall background, making direct observation of the fuel with HPGe detectors virtually impossible. Such observations can only be performed using precise collimators that restrict the detector's field of view to very small solid angles. This results in impracticably long dwell times for safeguards measurements targeting the weak isotopic lines of interest. In a proof-ofconcept experiment, a set of simple flat gamma-ray mirrors was used to observe the atomic florescence lines from U and Pu from a spent nuclear fuel pin. For the measurements, the mirrors were placed at the egress of an access port in a hot cell wall. A coarse collimator in the port restricted radiation from a fuel pin placed in front of the port to fully illuminate the front surface of the mirror assembly (0:5 x 3:8 cm2). The mirrors, consisting of highly polished silicon substrates deposited with WC/SiC multilayer coatings, were successfully used to deflect the lines of interest onto an HPGe detector while the intense primary radiation from the spent fuel was blocked by a lead beam stop. The gamma-ray mirror multilayer coatings used here at ∼100 keV, have been experimentally tested at energies as high as 645 keV, indicating that direct observation of nuclear emission lines from 239Pu should be possible with an appropriately designed optic. (author)

  1. Gamma ray transitions in de-excitation of 252Cf spontaneous fission fragments

    International Nuclear Information System (INIS)

    Khan, N.A.; Rashid, K.; Ahmad, M.; Qureshi, I.E.; Alam, G.D.; Ali, A.; Bhatti, N.; Horsch, F.

    1983-11-01

    Gamma rays in the range from 60 keV to 730 keV have been observed following the spontaneous fission of 252 Cf, with high resolution Ge(Li) detector, full width at half maximum (FWHM) of 700 eV at 122 keV, in coincidence with the two fission fragments observed with surface barrier detectors. A total number of 18, 636, 549 events were recorded over a run period of about 150 hours stretching over three weeks. The events were sorted to generate gamma ray spectra belonging to 2 amu intervals gamma of the fragment masses and 6 MeV intervals of the total kinetic energy released. Some of the prominent gamma lines belonging to various masses of the fission fragments have been identified. For some gamma lines, the intensities have been evaluated as a function of the total kinetic energy of the fission fragments. (authors)

  2. Dynamic gamma knife radiosurgery

    International Nuclear Information System (INIS)

    Luan Shuang; Swanson, Nathan; Chen Zhe; Ma Lijun

    2009-01-01

    Gamma knife has been the treatment of choice for various brain tumors and functional disorders. Current gamma knife radiosurgery is planned in a 'ball-packing' approach and delivered in a 'step-and-shoot' manner, i.e. it aims to 'pack' the different sized spherical high-dose volumes (called 'shots') into a tumor volume. We have developed a dynamic scheme for gamma knife radiosurgery based on the concept of 'dose-painting' to take advantage of the new robotic patient positioning system on the latest Gamma Knife C(TM) and Perfexion(TM) units. In our scheme, the spherical high dose volume created by the gamma knife unit will be viewed as a 3D spherical 'paintbrush', and treatment planning reduces to finding the best route of this 'paintbrush' to 'paint' a 3D tumor volume. Under our dose-painting concept, gamma knife radiosurgery becomes dynamic, where the patient moves continuously under the robotic positioning system. We have implemented a fully automatic dynamic gamma knife radiosurgery treatment planning system, where the inverse planning problem is solved as a traveling salesman problem combined with constrained least-square optimizations. We have also carried out experimental studies of dynamic gamma knife radiosurgery and showed the following. (1) Dynamic gamma knife radiosurgery is ideally suited for fully automatic inverse planning, where high quality radiosurgery plans can be obtained in minutes of computation. (2) Dynamic radiosurgery plans are more conformal than step-and-shoot plans and can maintain a steep dose gradient (around 13% per mm) between the target tumor volume and the surrounding critical structures. (3) It is possible to prescribe multiple isodose lines with dynamic gamma knife radiosurgery, so that the treatment can cover the periphery of the target volume while escalating the dose for high tumor burden regions. (4) With dynamic gamma knife radiosurgery, one can obtain a family of plans representing a tradeoff between the delivery time and

  3. Control system and automation of the spectrum acquisition for a perturbed gamma-gamma angular correlation spectrometer

    International Nuclear Information System (INIS)

    Stachowski, Ademir F.A.; Lapolli, André L.; Carbonari, Artur W.; Saxena, Rajendra N.

    2017-01-01

    This work reports results from the automation of data acquisition for a gamma-gamma perturbed angular correlation (PAC) spectrometer located in the hyperfine interactions laboratory (LIH) of IPEN. A PAC spectrometer comprises usually four scintillation detectors (BaF_3 for example) and carries out time measurements from gamma rays of any two combinations of detectors in coincidence. Gamma rays come from the decay of probe nuclei embedded into the material to be studied. Measurements are generally performed as a function of temperature. The fourth-detectors PAC spectrometer was automated in Java language because it is a multi platform and object oriented programming language, having, therefore, portability and longer lifetime due to the ease of implementation of peripherals. Finally, the software has a friendly and intuitive interface with the user being able to operate the hardware manually or automatically with time acquisitions up to 100 consecutive hours. Before each acquisition, the software sets the temperature, waits for temperature stability and records data in different files. Moreover, the software also saves in a file all information of relevant parameters during acquisition. (author)

  4. Control system and automation of the spectrum acquisition for a perturbed gamma-gamma angular correlation spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Stachowski, Ademir F.A.; Lapolli, André L.; Carbonari, Artur W.; Saxena, Rajendra N., E-mail: alapolli@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2017-11-01

    This work reports results from the automation of data acquisition for a gamma-gamma perturbed angular correlation (PAC) spectrometer located in the hyperfine interactions laboratory (LIH) of IPEN. A PAC spectrometer comprises usually four scintillation detectors (BaF{sub 3} for example) and carries out time measurements from gamma rays of any two combinations of detectors in coincidence. Gamma rays come from the decay of probe nuclei embedded into the material to be studied. Measurements are generally performed as a function of temperature. The fourth-detectors PAC spectrometer was automated in Java language because it is a multi platform and object oriented programming language, having, therefore, portability and longer lifetime due to the ease of implementation of peripherals. Finally, the software has a friendly and intuitive interface with the user being able to operate the hardware manually or automatically with time acquisitions up to 100 consecutive hours. Before each acquisition, the software sets the temperature, waits for temperature stability and records data in different files. Moreover, the software also saves in a file all information of relevant parameters during acquisition. (author)

  5. Radiation breeding researches in gamma field. Results of researches

    International Nuclear Information System (INIS)

    Morishita, Toshikazu

    2006-01-01

    Abstract of radiation breeding researches and outline of gamma field in IRB (Institute of Radiation Breeding) are described. The gamma field is a circular field of 100 m radius with 88.8TBqCo-60 source at the center. The field is surrounded by a shielding dike of 8 m in height. The effects of gamma irradiation on the growing plants, mutant by gamma radiation and plant molecular biological researches using mutant varieties obtained by the gamma field are explained. For examples, Japanese pear, chrysanthemum, Cytisus, Eustoma grandiflorum, Manila grass, tea and rose are reported. The mutant varieties in the gamma field, nine mutant varieties of flower colors in chrysanthemum, evergreen mutant lines in Manila grass, selection of self-compatible mutants in tea plant, and the plants of the gamma field recently are shown. (S.Y.)

  6. The Multi-Messenger Approach to High-Energy Gamma-Ray Sources

    CERN Document Server

    Paredes, Josep M; Torres, Diego F

    2008-01-01

    This book provides a theoretical and observational overview of the state of the art of gamma-ray astrophysics, and their impact and connection with the physics of cosmic rays and neutrinos. With the aim of shedding new and fresh light on the problem of the nature of the gamma-ray sources, particularly those yet unidentified, this book summarizes contributions to a workshop that continues with the series initiated by the meeting held at Tonantzintla in October 2000, and Hong-Kong in May 2004. This books will be of interest for all active researchers in the field of high energy astrophysics and astroparticle physics, as well as for graduate students entering into the subject.

  7. A Multi-Contact, Low Capacitance HPGe Detector for High Rate Gamma Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Cox, Christopher [XIA LLC, Hayward, CA (United States)

    2014-12-04

    The detection, identification and non-destructive assay of special nuclear materials and nuclear fission by-products are critically important activities in support of nuclear non-proliferation programs. Both national and international nuclear safeguard agencies recognize that current accounting methods for spent nuclear fuel are inadequate from a safeguards perspective. Radiation detection and analysis by gamma-ray spectroscopy is a key tool in this field, but no instrument exists that can deliver the required performance (energy resolution and detection sensitivity) in the presence of very high background count rates encountered in the nuclear safeguards arena. The work of this project addresses this critical need by developing a unique gamma-ray detector based on high purity germanium that has the previously unachievable property of operating in the 1 million counts-per-second range while achieving state-of-the-art energy resolution necessary to identify and analyze the isotopes of interest. The technical approach was to design and fabricate a germanium detector with multiple segmented electrodes coupled to multi-channel high rate spectroscopy electronics. Dividing the germanium detector’s signal electrode into smaller sections offers two advantages; firstly, the energy resolution of the detector is potentially improved, and secondly, the detector is able to operate at higher count rates. The design challenges included the following; determining the optimum electrode configuration to meet the stringent energy resolution and count rate requirements; determining the electronic noise (and therefore energy resolution) of the completed system after multiple signals are recombined; designing the germanium crystal housing and vacuum cryostat; and customizing electronics to perform the signal recombination function in real time. In this phase I work, commercial off-the-shelf electrostatic modeling software was used to develop the segmented germanium crystal geometry

  8. Automation system for measurement of gamma-ray spectra of induced activity for multi-element high-volume neutron activation analysis at the IBR-2 reactor of FLNP at JINR

    International Nuclear Information System (INIS)

    Pavlov, S.S.; Dmitriev, A.Yu.; Chepurchenko, I.A.; Frontas'eva, M.V.

    2014-01-01

    The automation system for measurement of induced activity of gamma-ray spectra for multi-element high-volume neutron activation analysis (NAA) was designed, developed and implemented at the IBR-2 reactor. The system consists of three devices of automatic sample changers for three Canberra HPGe detector-based gamma spectrometry systems. Each sample changer consists of two-axis linear positioning module M202A by DriveSet (DriveSet.de) company and disk with 45 slots for containers with samples. Control of automatic sample changer is performed by the Xemo S360U controller by Systec (systec.de) company. Positioning accuracy can reach 0.1 mm. Special software performs automatic changing of samples and measurement of gamma spectra at constant interaction with the NAA database. The system is unique and can be recommended for other laboratories as one of the possible ways of the NAA integrated automation

  9. Vessel Segmentation in Retinal Images Using Multi-scale Line Operator and K-Means Clustering.

    Science.gov (United States)

    Saffarzadeh, Vahid Mohammadi; Osareh, Alireza; Shadgar, Bita

    2014-04-01

    Detecting blood vessels is a vital task in retinal image analysis. The task is more challenging with the presence of bright and dark lesions in retinal images. Here, a method is proposed to detect vessels in both normal and abnormal retinal fundus images based on their linear features. First, the negative impact of bright lesions is reduced by using K-means segmentation in a perceptive space. Then, a multi-scale line operator is utilized to detect vessels while ignoring some of the dark lesions, which have intensity structures different from the line-shaped vessels in the retina. The proposed algorithm is tested on two publicly available STARE and DRIVE databases. The performance of the method is measured by calculating the area under the receiver operating characteristic curve and the segmentation accuracy. The proposed method achieves 0.9483 and 0.9387 localization accuracy against STARE and DRIVE respectively.

  10. Comparison of the multi-drug resistant human hepatocellular carcinoma cell line Bel-7402/ADM model established by three methods

    Directory of Open Access Journals (Sweden)

    Zhong Xingguo

    2010-08-01

    Full Text Available Abstract Background To compare the biological characteristics of three types of human hepatocellular carcinoma multi-drug resistant cell sub-lines Bel-7402/ADM models established by three methods. Methods Established human hepatocellular carcinoma adriamycin (ADM multi-drug resistant cell sub-lines models Bel-7402/ADMV, Bel-7402/ADML and Bel-7402/ADMS by three methods of in vitro concentration gradient increased induction, nude mice liver-implanted induction and subcutaneous-implanted induction respectively. Phase contrast microscopy was used to observe the cells and the MTT (methyl thiazolyl tetrazolium method was used to detect drug resistance of the three different sub-lines of cells. Results The three groups of drug resistant cells, Bel-7402/ADMV, Bel-7402/ADML and Bel-7402/ADMS generated cross-resistance to ADM and CDDP (cis-Diaminedichloroplatinum, but showed a significant difference in resistance to Bel-7402 IC50 value (P V, 46 h (Bel-7402/ADML, and 45 h (Bel-7402/ADMS. The excretion rates of ADM were significantly increased compared with the parent cell (34.14% line and were 81.06% (Bel-7402/ADMV, 66.56% (Bel-7402/ADML and 61.56% (Bel-7402/ADMS. Expression of P-gp and MRP in the three groups of resistant cells was significantly enhanced (P P > 0.05. Conclusions Stable resistance was involved in the resistant cell line model established by the above three methods. Liver implantation was a good simulation of human hepatocellular and proved to be an ideal model with characteristics similar to human hepatocellular biology and the pharmacokinetics of anticancer drugs.

  11. THE BROAD-LINED Type Ic SN 2012ap AND THE NATURE OF RELATIVISTIC SUPERNOVAE LACKING A GAMMA-RAY BURST DETECTION

    Energy Technology Data Exchange (ETDEWEB)

    Milisavljevic, D.; Margutti, R.; Parrent, J. T.; Soderberg, A. M.; Sanders, N. E.; Kamble, A.; Chakraborti, S.; Drout, M. R.; Kirshner, R. P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Fesen, R. A. [Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, NH 03755 (United States); Mazzali, P. [Astrophysics Research Institute, Liverpool John Moores University, Liverpool L3 5RF (United Kingdom); Maeda, K. [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Cenko, S. B. [Astrophysics Science Division, NASA Goddard Space Flight Center, Mail Code 661, Greenbelt, MD 20771 (United States); Silverman, J. M. [University of Texas at Austin, 1 University Station C1400, Austin, TX 78712-0259 (United States); Filippenko, A. V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Pickering, T. E. [Southern African Large Telescope, P.O. Box 9, Observatory 7935, Cape Town (South Africa); Kawabata, K. [Hiroshima Astrophysical Science Center, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Hattori, T. [Subaru Telescope, National Astronomical Observatory of Japan, Hilo, HI 96720 (United States); Hsiao, E. Y. [Carnegie Observatories, Las Campanas Observatory, Colina El Pino, Casilla 601 (Chile); Stritzinger, M. D., E-mail: dmilisav@cfa.harvard.edu [Department of Physics and Astronomy, Aarhus University, Ny Munkegade, DK-8000 Aarhus C (Denmark); and others

    2015-01-20

    We present ultraviolet, optical, and near-infrared observations of SN 2012ap, a broad-lined Type Ic supernova in the galaxy NGC 1729 that produced a relativistic and rapidly decelerating outflow without a gamma-ray burst signature. Photometry and spectroscopy follow the flux evolution from –13 to +272 days past the B-band maximum of –17.4 ± 0.5 mag. The spectra are dominated by Fe II, O I, and Ca II absorption lines at ejecta velocities of v ≈ 20,000 km s{sup –1} that change slowly over time. Other spectral absorption lines are consistent with contributions from photospheric He I, and hydrogen may also be present at higher velocities (v ≳ 27,000 km s{sup –1}). We use these observations to estimate explosion properties and derive a total ejecta mass of ∼2.7 M {sub ☉}, a kinetic energy of ∼1.0 × 10{sup 52} erg, and a {sup 56}Ni mass of 0.1-0.2 M {sub ☉}. Nebular spectra (t > 200 days) exhibit an asymmetric double-peaked [O I] λλ6300, 6364 emission profile that we associate with absorption in the supernova interior, although toroidal ejecta geometry is an alternative explanation. SN 2012ap joins SN 2009bb as another exceptional supernova that shows evidence for a central engine (e.g., black hole accretion or magnetar) capable of launching a non-negligible portion of ejecta to relativistic velocities without a coincident gamma-ray burst detection. Defining attributes of their progenitor systems may be related to notable observed properties including environmental metallicities of Z ≳ Z {sub ☉}, moderate to high levels of host galaxy extinction (E(B – V) > 0.4 mag), detection of high-velocity helium at early epochs, and a high relative flux ratio of [Ca II]/[O I] >1 at nebular epochs. These events support the notion that jet activity at various energy scales may be present in a wide range of supernovae.

  12. The Broad-Lined Type Ic SN 2012ap and the Nature of Relativistic Supernovae Lacking a Gamma-Ray Burst Detection

    Science.gov (United States)

    Milisavljevic, D.; Margutti, R.; Parrent, J. T.; Soderberg, A. M.; Fesen, R. A.; Mazzali, P.; Maeda, K.; Sanders, N. E.; Cenko, S. B.; Silverman, J. M.

    2014-01-01

    We present ultraviolet, optical, and near-infrared observations of SN2012ap, a broad-lined Type Ic supernova in the galaxy NGC 1729 that produced a relativistic and rapidly decelerating outflow without a gamma-ray burst signature. Photometry and spectroscopy follow the flux evolution from -13 to +272 days past the B-band maximum of -17.4 +/- 0.5 mag. The spectra are dominated by Fe II, O I, and Ca II absorption lines at ejecta velocities of v approx. 20,000 km s(exp. -1) that change slowly over time. Other spectral absorption lines are consistent with contributions from photospheric He I, and hydrogen may also be present at higher velocities (v approx. greater than 27,000 km s(exp. -1)). We use these observations to estimate explosion properties and derive a total ejecta mass of 2.7 Solar mass, a kinetic energy of 1.0×1052 erg, and a (56)Ni mass of 0.1-0.2 Solar mass. Nebular spectra (t > 200 d) exhibit an asymmetric double-peaked [O I] lambda lambda 6300, 6364 emission profile that we associate with absorption in the supernova interior, although toroidal ejecta geometry is an alternative explanation. SN2012ap joins SN2009bb as another exceptional supernova that shows evidence for a central engine (e.g., black-hole accretion or magnetar) capable of launching a non-negligible portion of ejecta to relativistic velocities without a coincident gamma-ray burst detection. Defining attributes of their progenitor systems may be related to notable properties including above-average environmental metallicities of Z approx. greater than Solar Z, moderate to high levels of host-galaxy extinction (E(B -V ) > 0.4 mag), detection of high-velocity helium at early epochs, and a high relative flux ratio of [Ca II]/[O I] > 1 at nebular epochs. These events support the notion that jet activity at various energy scales may be present in a wide range of supernovae.

  13. BROAD ABSORPTION LINE VARIABILITY ON MULTI-YEAR TIMESCALES IN A LARGE QUASAR SAMPLE

    Energy Technology Data Exchange (ETDEWEB)

    Filiz Ak, N.; Brandt, W. N.; Schneider, D. P. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Hall, P. B. [Department of Physics and Astronomy, York University, 4700 Keele St., Toronto, Ontario, M3J 1P3 (Canada); Anderson, S. F. [Astronomy Department, University of Washington, Seattle, WA 98195 (United States); Hamann, F. [Department of Astronomy, University of Florida, Gainesville, FL 32611-2055 (United States); Lundgren, B. F. [Department of Astronomy, University of Wisconsin, Madison, WI 53706 (United States); Myers, Adam D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Pâris, I. [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Petitjean, P. [Universite Paris 6, Institut d' Astrophysique de Paris, 75014, Paris (France); Ross, Nicholas P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 92420 (United States); Shen, Yue [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., MS-51, Cambridge, MA 02138 (United States); York, Don, E-mail: nfilizak@astro.psu.edu [The University of Chicago, Department of Astronomy and Astrophysics, Chicago, IL 60637 (United States)

    2013-11-10

    We present a detailed investigation of the variability of 428 C IV and 235 Si IV broad absorption line (BAL) troughs identified in multi-epoch observations of 291 quasars by the Sloan Digital Sky Survey-I/II/III. These observations primarily sample rest-frame timescales of 1-3.7 yr over which significant rearrangement of the BAL wind is expected. We derive a number of observational results on, e.g., the frequency of BAL variability, the velocity range over which BAL variability occurs, the primary observed form of BAL-trough variability, the dependence of BAL variability upon timescale, the frequency of BAL strengthening versus weakening, correlations between BAL variability and BAL-trough profiles, relations between C IV and Si IV BAL variability, coordinated multi-trough variability, and BAL variations as a function of quasar properties. We assess implications of these observational results for quasar winds. Our results support models where most BAL absorption is formed within an order-of-magnitude of the wind-launching radius, although a significant minority of BAL troughs may arise on larger scales. We estimate an average lifetime for a BAL trough along our line-of-sight of a few thousand years. BAL disappearance and emergence events appear to be extremes of general BAL variability, rather than being qualitatively distinct phenomena. We derive the parameters of a random-walk model for BAL EW variability, finding that this model can acceptably describe some key aspects of EW variability. The coordinated trough variability of BAL quasars with multiple troughs suggests that changes in 'shielding gas' may play a significant role in driving general BAL variability.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-09-28

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

  15. Multi-Isotope Process (MIP) Monitor: A Near-Real-Time Monitor For Reprocessing Facilities

    International Nuclear Information System (INIS)

    Schwantes, Jon M.; Douglas, Matthew; Orton, Christopher R.; Fraga, Carlos G.; Christensen, Richard

    2008-01-01

    The threat of protracted diversion of Pu from commercial reprocessing operations is perhaps the greatest concern to national and international agencies tasked with safeguarding these facilities. While it is generally understood that a method for direct monitoring of process on-line and in near-real time (NRT) would be the best defense against protracted diversion scenarios, an effective method with these qualities has yet to be developed. Here, we attempt to bridge this gap by proposing an on-line NRT process monitoring method that should be sensitive to minor alterations in process conditions and compatible with small, easily deployable, detection systems. This Approach is known as the Multi-Isotope Process (MIP) Monitor and involves the determination and recognition of the contaminant pattern within a process stream for a suite of indicator (radioactive) elements present in the spent fuel as a function of process variables. Utilization of a suite of radio-elements, including ones with multiple oxidation states, decreases the likelihood that attempts to divert Pu by altering the ReDox environment within the process would go undetected. In addition, by identifying gamma-emitting indicator isotopes, this Approach might eliminate the need for bulky neutron detection systems, relying instead on small, portable, high-resolution gamma detectors easily deployable throughout the facility

  16. Robotic tool positioning process using a multi-line off-axis laser triangulation sensor

    Science.gov (United States)

    Pinto, T. C.; Matos, G.

    2018-03-01

    Proper positioning of a friction stir welding head for pin insertion, driven by a closed chain robot, is important to ensure quality repair of cracks. A multi-line off-axis laser triangulation sensor was designed to be integrated to the robot, allowing relative measurements of the surface to be repaired. This work describes the sensor characteristics, its evaluation and the measurement process for tool positioning to a surface point of interest. The developed process uses a point of interest image and a measured point cloud to define the translation and rotation for tool positioning. Sensor evaluation and tests are described. Keywords: laser triangulation, 3D measurement, tool positioning, robotics.

  17. Gamma Radiation from Fission Fragments

    International Nuclear Information System (INIS)

    Higbie, Jack

    1969-10-01

    The gamma radiation from the fragments of the thermal neutron fission of 235 U has been investigated, and the preliminary data are presented here with suggestions for further lines of research and some possible interpretations of the data. The data have direct bearing on the fission process and the mode of fragment de-excitation. The parameters measured are the radiation decay curve for the time interval (1 - 7) x 10 -10 sec after fission, the photon yield, the total gamma ray energy yield, and the average photon energy. The last three quantities are measured as a function of the fragment mass

  18. Gamma Radiation from Fission Fragments

    Energy Technology Data Exchange (ETDEWEB)

    Higbie, Jack

    1969-10-15

    The gamma radiation from the fragments of the thermal neutron fission of {sup 235}U has been investigated, and the preliminary data are presented here with suggestions for further lines of research and some possible interpretations of the data. The data have direct bearing on the fission process and the mode of fragment de-excitation. The parameters measured are the radiation decay curve for the time interval (1 - 7) x 10{sup -10} sec after fission, the photon yield, the total gamma ray energy yield, and the average photon energy. The last three quantities are measured as a function of the fragment mass.

  19. Radiosensitivity of Prostate Cancer Cell Lines for Irradiation from Beta Particle-emitting Radionuclide ¹⁷⁷Lu Compared to Alpha Particles and Gamma Rays.

    Science.gov (United States)

    Elgqvist, Jörgen; Timmermand, Oskar Vilhelmsson; Larsson, Erik; Strand, Sven-Erik

    2016-01-01

    The purpose of the present study was to investigate the radiosensitivity of the prostate cancer cell lines LNCaP, DU145, and PC3 when irradiated with beta particles emitted from (177)Lu, and to compare the effect with irradiation using alpha particles or gamma rays. Cells were irradiated with beta particles emitted from (177)Lu, alpha particles from (241)Am, or gamma rays from (137)Cs. A non-specific polyclonal antibody was labeled with (177)Lu and used to irradiate cells in suspension with beta particles. A previously described in-house developed alpha-particle irradiator based on a (241)Am source was used to irradiate cells with alpha particles. External gamma-ray irradiation was achieved using a standard (137)Cs irradiator. Cells were irradiated to absorbed doses equal to 0, 0.5, 1, 2, 4, 6, 8, or 10 Gy. The absorbed doses were calculated as mean absorbed doses. For evaluation of cell survival, the tetrazolium-based WST-1 assay was used. After irradiation, WST-1 was added to the cell solutions, incubated, and then measured for level of absorbance at 450 nm, indicating the live and viable cells. LNCaP, DU145, and PC3 cell lines all had similar patterns of survival for the different radiation types. No significant difference in surviving fractions were observed between cells treated with beta-particle and gamma-ray irradiation, represented for example by the surviving fraction values (mean±SD) at 2, 6, and 10 Gy (SF2, SF6, and SF10) for DU145 after beta-particle irradiation: 0.700±0.090, 0.186±0.050 and 0.056±0.010, respectively. A strong radiosensitivity to alpha particles was observed, with SF2 values of 0.048±0.008, 0.018±0.006 and 0.015±0.005 for LNCaP, DU145, and PC3, respectively. The surviving fractions after irradiation using beta particles or gamma rays did not differ significantly at the absorbed dose levels and dose rates used. Irradiation using alpha particles led to a high level of cell killing. The results show that the beta-particle emitter

  20. Observing with a space-borne gamma-ray telescope: selected results from INTEGRAL

    International Nuclear Information System (INIS)

    Schanne, Stephane

    2006-01-01

    The International Gamma-Ray Astrophysics Laboratory, i.e. the INTEGRAL satellite of ESA, in orbit since about 3 years, performs gamma-ray observations of the sky in the 15 keV to 8 MeV energy range. Thanks to its imager IBIS, and in particular the ISGRI detection plane based on 16384 CdTe pixels, it achieves an excellent angular resolution (12 arcmin) for point source studies with good continuum spectrum sensitivity. Thanks to its spectrometer SPI, based on 19 germanium detectors maintained at 85 K by a cryogenic system, located inside an active BGO veto shield, it achieves excellent spectral resolution of about 2 keV for 1 MeV photons, which permits astrophysical gamma-ray line studies with good narrow-line sensitivity. In this paper we review some goals of gamma-ray astronomy from space and present the INTEGRAL satellite, in particular its instruments ISGRI and SPI. Ground and in-flight calibration results from SPI are presented, before presenting some selected astrophysical results from INTEGRAL. In particular results on point source searches are presented, followed by results on nuclear astrophysics, exemplified by the study of the 1809 keV gamma-ray line from radioactive 26 Al nuclei produced by the ongoing stellar nucleosynthesis in the Galaxy. Finally a review on the study of the positron-electron annihilation in the Galactic center region, producing 511 keV gamma-rays, is presented

  1. On-Line High Dose-rate Gamma Irradiation Test of the Profibus/DP module

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jai Wan; Choi, Young Soo; Kim, Chang Hoi; Koo, In Soo; Hong, Seok Boong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2009-05-15

    The field bus data communication is considered for application in nuclear environments. The nuclear facilities, including nuclear power plants, high radioactivity waste disposals, reprocessing plants and thermonuclear fusion installations can benefit from the unique advantages of the field bus communication network for the smart field instruments and controls. A major problem which arises when dealing with one in these nuclear environments, in special circumstances such as the RCS (reactor coolant system) area, is the presence of high gamma-ray irradiation fields. Radioactive constraints for the DBA(design basis accident) qualification of the RTD transmitter installed in the inside of the RCS pump are typically on the order of 4kGy/h with total doses up to 10kGy. In order to use an industrial field bus communication network as an ad-hoc sensor data link in the vicinity of the RCS area of the nuclear power plant, the robust survivability of these system in such intense gamma-radiation fields therefore needs to be verified. We have conducted high dose-rate (up to 4kGy) gamma irradiation experiments on a profibus/DP communication module. In this paper we describe the evolution of its basic characteristics with high dose-rate gamma irradiation and shortly explain the observed phenomena.

  2. Unattented mode monitoring of high resolution gamma-ray spectra

    International Nuclear Information System (INIS)

    Smith, B.G.R.; Van Dyck, P.; Debraix, P.

    1991-01-01

    An Isotope Monitoring System (IMS) for unattended spectrum acquisition is described. This consists of a simple low cost flexible software package running on a Compaq 80386 and controlling up to 4 Canberra Packard System 100 multi-channel analyzer (MCA) cards. The IMS permits the independent configuration of each of the 4 MCA cards for different monitoring cycles and for different spectrum acquisition cycles each being based upon different trigger criteria. In this way IMS is able to automatically identify events, time tag them, and acquire and store valid spectra corresponding to those event. An additional feature of IMS permits to run a Multigroup Analysis (MGA) software package for the determination of plutonium isotopic compositions in batch mode. One particular application is discussed which consists of 4 high resolution gamma-ray detector systems connected together to the IMS for unattended spectrum acquisition. The off-line batch mode analysis of the spectra using MGA is also discussed

  3. Characterization of the gamma radiation in space and in the atmosphere

    International Nuclear Information System (INIS)

    Lee, M.A.

    1986-05-01

    A characterization of the gamma-ray fields found in space and in the atmosphere is given. Included are values for the energies and intensities of gamma rays as observed in several experiments and reported in the open literature. Characteristics of the diffuse gamma-ray continuum are presented along with a brief discussion of the sources of this radiation. Also given are discrete gamma-ray line energies and intensities which have been observed in space and in the atmosphere. 37 refs., 7 figs., 12 tabs

  4. The measurement of gamma ray induced heating in a mixed neutron and gamma ray environment

    International Nuclear Information System (INIS)

    Chiu, H.K.

    1991-10-01

    The problem of measuring the gamma heating in a mixed DT neutron and gamma ray environment was explored. A new detector technique was developed to make this measurement. Gamma heating measurements were made in a low-Z assembly irradiated with 14-Mev neutrons and (n, n') gammas produced by a Texas Nuclear Model 9400 neutron generator. Heating measurements were made in the mid-line of the lattice using a proportional counter operating in the Continuously-varied Bias-voltage Acquisition mode. The neutron-induced signal was separated from the gamma-induced signal by exploiting the signal rise-time differences inherent to radiations of different linear energy transfer coefficient, which are observable in a proportional counter. The operating limits of this measurement technique were explored by varying the counter position in the low-Z lattice, hence changing the irradiation spectrum observed. The experiment was modelled numerically to help interpret the measured results. The transport of neutrons and gamma rays in the assembly was modelled using the one- dimensional radiation transport code ANISN/PC. The cross-section set used for these calculations was derived from the ENDF/B-V library using the code MC 2 -2 for the case of DT neutrons slowing down in a low-Z material. The calculated neutron and gamma spectra in the slab and the relevant mass-stopping powers were used to construct weighting factors which relate the energy deposition in the counter fill-gas to that in the counter wall and in the surrounding material. The gamma energy deposition at various positions in the lattice is estimated by applying these weighting factors to the measured gamma energy deposition in the counter at those locations

  5. EPR structure of the gamma irradiated alanine spectrum

    International Nuclear Information System (INIS)

    Cabral P, A.; Jimenez D, H.; Urena N, F.; Galindo, S.; Bosch, P.

    1992-03-01

    In this study is shown that the broadened five-line EPR pattern of the gamma irradiated alanine possibly decomposes into a more complex pattern when the recorded spectrum is subject to an operation of deconvolution. The EPR powder spectra of gamma irradiated DL- and L-alanine with and without binders are analysed. In all recorded spectra, each observed line is resolved into an asymmetrical triplet when a Gaussian distribution of 8.2 gauss width is removed, by deconvolution, from the observed spectrum. On the other hand, from a simple fitting analysis carried out on the original data, one encounters that some calculated relations between characteristic parameters, such as intensity ratios, deviate consistently from assumed height ratios. Both, from deconvolution and fitting results, a different structure is suggested for the observed broadened five-line EPR pattern of γ-irradiated powder DL- and L-alanine. (Author)

  6. Evaluation of gamma spectroscopy gauge for uranium-plutonium assay

    International Nuclear Information System (INIS)

    Notea, A.; Segal, Y.

    1975-01-01

    A procedure is presented for the characterization of a gamma passive method for nondestructive analysis of nuclear fuel. The approach provides an organized and systematic way for optimizing the assay system. The key function is the relative resolving power defined as the smallest relative change in the Quantity of radionuclide measured, that may be detected within a certain confidence level. This function is derived for nuclear fuel employing a model based on empirical parameters. The ability to detect changes in fuels of binary and trinary compositions with a 50 cc Ge(Li) at a 1 min counting period is discussed. As an example to a binary composition, an enriched uranium fuel was considered. The 185 keV and 1001 keV gamma lines are used for the assay of 235 U and 238 U respectively. As a trinary composition a plutonium-containing gamma line. The interference of the high energy lines is carefully analyzed, and numerical results are presented. For both cases the range of measurement under specific accuracy demands is determined. The approach described is suitable also for evaluation of other passive as well as active assay methods. (author)

  7. Multi-line split DNA synthesis: a novel combinatorial method to make high quality peptide libraries

    Directory of Open Access Journals (Sweden)

    Ueno Shingo

    2004-09-01

    Full Text Available Abstract Background We developed a method to make a various high quality random peptide libraries for evolutionary protein engineering based on a combinatorial DNA synthesis. Results A split synthesis in codon units was performed with mixtures of bases optimally designed by using a Genetic Algorithm program. It required only standard DNA synthetic reagents and standard DNA synthesizers in three lines. This multi-line split DNA synthesis (MLSDS is simply realized by adding a mix-and-split process to normal DNA synthesis protocol. Superiority of MLSDS method over other methods was shown. We demonstrated the synthesis of oligonucleotide libraries with 1016 diversity, and the construction of a library with random sequence coding 120 amino acids containing few stop codons. Conclusions Owing to the flexibility of the MLSDS method, it will be able to design various "rational" libraries by using bioinformatics databases.

  8. Search for two-{gamma} sum-energy peaks in the decay out of superdeformed bands

    Energy Technology Data Exchange (ETDEWEB)

    Blumenthal, D.; Khoo, T.L.; Lauritsen, T. [and others

    1995-08-01

    The spectrum of {gamma}rays decaying out of the superdeformed (SD) band in {sup 192}Hg has a quasicontinuous distribution. Whereas methods to construct level schemes from discrete lines in coincidence spectra are well established, new techniques must still be developed to extract information from coincidences involving quasicontinuous {gamma}rays. From an experiment using Eurogam, we obtained impressively clean 1- and 2-dimensional {gamma} spectra from pairwise or single gates, respectively, on the transitions of the SD band in {sup 192}Hg. We investigated methods to exploit the 2-dimensional quasicontinuum spectra coincident with the SD band to determine the excitation energy of the SD band above the normal yrast line. No strong peaks were observed in the 2-{gamma} sum spectra; only candidates of peaks at a 2-3 {sigma} level were found. This suggests that 2-{gamma} decay is not the dominant decay branch out of SD bands, consistent with the observed multiplicity of 3.2. We shall next search for peaks in sum-spectra of 3 {gamma}s.

  9. Computer generated multi-color graphics in whole body gamma spectral analysis

    International Nuclear Information System (INIS)

    Phillips, W.G.; Curtis, S.P.; Environmental Protection Agency, Las Vegas, NV)

    1984-01-01

    A medium resolution color graphics terminal (512 x 512 pixels) was appended to a computerized gamma spectrometer for the display of whole body counting data. The color display enhances the ability of a spectroscopist to identify at a glance multicolored spectral regions of interest immediate qualitative interpretation. Spectral data from subjects containing low concentrations of gamma emitters obtained by both NaI(T1) and phoswich detectors are viewed by the method. In addition, software generates a multispectral display by which the gross, background, and net spectra are displayed in color simultaneously on a single screen

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-01-20

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

  11. Very high energy gamma ray astronomy from Hanle

    International Nuclear Information System (INIS)

    Chitnis, Varsha R.

    2015-01-01

    Over a past decade very high energy (VHE) gamma ray astronomy has emerged as a major astronomical discipline. In India, we have a long tradition of experiments in this field. Few years ago, multi-institutional Himalayan Gamma Ray Observatory (HiGRO) collaboration was formed to set up VHE gamma rays experiments at Hanle, a high altitude location in Himalayas. HAGAR, the first phase of this collaboration is operational since 2008. HAGAR has successfully detected VHE gamma ray emission from some of the extragalactic objects like Mrk 421, Mrk 501 as well as galactic sources including Crab nebula/pulsar. Details of HAGAR telescope system and results obtained will be discussed. HiGRO is now gearing up for the next phase, i.e. 21 m diameter MACE telescope, which is being installed at Hanle at present. Details of MACE telescope system and future plans will be discussed. (author)

  12. Gamma ray bursts: Current status of observations and theory

    International Nuclear Information System (INIS)

    Meegan, C.A.

    1990-04-01

    Gamma ray bursts display a wide range of temporal and spectral characteristics, but typically last several seconds and emit most of their energy in a low energy, gamma ray region. The burst sources appear to be isotropically distributed on the sky. Several lines of evidence suggest magnetic neutron stars as sources for bursts. A variety of energy sources and emission mechanisms are proposed

  13. Gamma camera

    International Nuclear Information System (INIS)

    Reiss, K.H.; Kotschak, O.; Conrad, B.

    1976-01-01

    A gamma camera with a simplified setup as compared with the state of engineering is described permitting, apart from good localization, also energy discrimination. Behind the usual vacuum image amplifier a multiwire proportional chamber filled with trifluorine bromium methane is connected in series. Localizing of the signals is achieved by a delay line, energy determination by means of a pulse height discriminator. With the aid of drawings and circuit diagrams, the setup and mode of operation are explained. (ORU) [de

  14. Dynamic gamma knife radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Luan Shuang; Swanson, Nathan; Chen Zhe [Department of Computer Science, University of New Mexico, Albuquerque, NM 87131 (United States); Ma Lijun [Department of Radiation Oncology, University of California San Francisco, San Francisco, CA 94143 (United States)], E-mail: sluan@cs.unm.edu, E-mail: nate@cs.unm.edu, E-mail: zchen@cs.unm.edu, E-mail: lijunma@radonc.ucsf.edu

    2009-03-21

    Gamma knife has been the treatment of choice for various brain tumors and functional disorders. Current gamma knife radiosurgery is planned in a 'ball-packing' approach and delivered in a 'step-and-shoot' manner, i.e. it aims to 'pack' the different sized spherical high-dose volumes (called 'shots') into a tumor volume. We have developed a dynamic scheme for gamma knife radiosurgery based on the concept of 'dose-painting' to take advantage of the new robotic patient positioning system on the latest Gamma Knife C(TM) and Perfexion(TM) units. In our scheme, the spherical high dose volume created by the gamma knife unit will be viewed as a 3D spherical 'paintbrush', and treatment planning reduces to finding the best route of this 'paintbrush' to 'paint' a 3D tumor volume. Under our dose-painting concept, gamma knife radiosurgery becomes dynamic, where the patient moves continuously under the robotic positioning system. We have implemented a fully automatic dynamic gamma knife radiosurgery treatment planning system, where the inverse planning problem is solved as a traveling salesman problem combined with constrained least-square optimizations. We have also carried out experimental studies of dynamic gamma knife radiosurgery and showed the following. (1) Dynamic gamma knife radiosurgery is ideally suited for fully automatic inverse planning, where high quality radiosurgery plans can be obtained in minutes of computation. (2) Dynamic radiosurgery plans are more conformal than step-and-shoot plans and can maintain a steep dose gradient (around 13% per mm) between the target tumor volume and the surrounding critical structures. (3) It is possible to prescribe multiple isodose lines with dynamic gamma knife radiosurgery, so that the treatment can cover the periphery of the target volume while escalating the dose for high tumor burden regions. (4) With dynamic gamma knife radiosurgery, one can

  15. Gamma spectroscopy: from steady beams to radioactive beams

    International Nuclear Information System (INIS)

    Stezowski, O.

    2008-06-01

    The author gives an overview of his research works in the field of gamma spectroscopy. First, he recalls some results of experiments performed for the study of peculiar structures associated with different modes of nucleus rotation, and notably in the case of collective rotation of deformed and even super-deformed nuclei. Then, he details tools and methods used to experimentally determine the level scheme. The main characteristics of steady and radioactive beams are briefly presented, and their complementarities and differences are highlighted. Specific spectrometers and sensors are described. In a last chapter, the author discusses several research projects he is involved in, and more particularly the 'gamma tracking' which is the fundamental principle for gamma multi-sensors of the next generations

  16. Studies of the $\\beta$-decay of Sr nuclei on and near the N=Z Line with a Total Absorption Gamma-ray Spectrometer

    CERN Multimedia

    Marechal, F; Caballero ontanaya, L

    2002-01-01

    In the framework of the investigation of the shapes of the ground states of the parent nucleus, we propose to carry out measurements of the complete Gamow-Teller strength distribution for the $^{76-80}$Sr isotopes, with a new Total Absorption Gamma Spectrometer installed on a new beam line. The results will be compared with theoretical calculations based on the mean field approach. A brief report on the IS370 experiment on $^{72-75}$Kr decay, which was recently performed at ISOLDE, will be given and the performance of the sum spectrometer will be presented.

  17. Physiological characteristics of cucumber seed production plants by presowing laser and gamma irradiation

    International Nuclear Information System (INIS)

    Cholakov, D.; Petkova, V.

    1994-01-01

    Seeds from G-3 maternal line of hybrid cucumber cultivar Pobeda F 1 were treated with helium-neon 632.8 nm laser-exit power 20 mW and gamma-rays ( 60 Co) in a field experiment under conditions suitable for hybrid seed production. The irradiation was carried out a week before sowing and the following variants were investigated: 1. sevenfold laser irradiation; 2. 10 Gy gamma irradiation; 3. combined laser + gamma rays irradiation. Seeds from the parent line were not irradiated. A positive effect of irradiation on the photosynthetic intensity, content of plastid pigments in leaves and activity of catalase and peroxidase has been observed. (author)

  18. Radiosensitivity of lentil beam (Lens culinaris L.) to gamma-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Min Kyu; Ryu, Jaihyunk; Jeong, Sang Wook; Kim, Jin Baek; Kang, Si Young; Kwon, Soon Jae [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2017-02-15

    We examined damages from gamma-irradiation and determined the optimal gamma ray dose for mutation breeding in lentil (Lens culinaris L.) bean. Four individual lines (L-C, L-2, L-8 and L-9), that have remarkable adaptability in South Korea were gamma-irradiated at doses of 50, 70, 100, 200, 300, 400, and 500 Gy. The germination rate of seed decreased as the dose increased over 50 Gy in all lines. However, LD{sub 50} and RD{sub 50} were different among lines. The median lethal doses (LD50) were approximately 127 (L-C), 74 (L-2), 95 (L-8), and 144 (L-9) Gy. The median reduction doses (RD{sub 50}) for plant height, number of leaves, root length, and flash weight were 156, 176, 150, and 180 Gy for L-C, 253, 198, 127, and 142 Gy for L-2, 188, 175, 200, and 190 Gy for L-8, and 162, 210, 224, and 184 for L-9, respectively. The growth characteristics of the M1 generation decreased as the dose increased over 70 Gy. The optimal doses of gamma irradiation for mutation breeding of lentil were determined to be 70 Gy (L-2, L-8) and 100 Gy (L-C, L-9). We performed the comet assay to observe nuclear DNA damage induced by gamma-irradiation. In comet assay, a clear difference was identified over 100 Gy treatments. With increasing doses of gamma-ray in the range of 50 to 500 Gy, the rate of head DNA was decreased significantly from 97.5% to 81.6%. Tail length was consecutively increased from 1.9 μm to 17.4 μm. Our result provides basic information for construction of mutant pools in lentils.

  19. Radiosensitivity of lentil beam (Lens culinaris L.) to gamma-irradiation

    International Nuclear Information System (INIS)

    Lee, Min Kyu; Ryu, Jaihyunk; Jeong, Sang Wook; Kim, Jin Baek; Kang, Si Young; Kwon, Soon Jae

    2017-01-01

    We examined damages from gamma-irradiation and determined the optimal gamma ray dose for mutation breeding in lentil (Lens culinaris L.) bean. Four individual lines (L-C, L-2, L-8 and L-9), that have remarkable adaptability in South Korea were gamma-irradiated at doses of 50, 70, 100, 200, 300, 400, and 500 Gy. The germination rate of seed decreased as the dose increased over 50 Gy in all lines. However, LD_5_0 and RD_5_0 were different among lines. The median lethal doses (LD50) were approximately 127 (L-C), 74 (L-2), 95 (L-8), and 144 (L-9) Gy. The median reduction doses (RD_5_0) for plant height, number of leaves, root length, and flash weight were 156, 176, 150, and 180 Gy for L-C, 253, 198, 127, and 142 Gy for L-2, 188, 175, 200, and 190 Gy for L-8, and 162, 210, 224, and 184 for L-9, respectively. The growth characteristics of the M1 generation decreased as the dose increased over 70 Gy. The optimal doses of gamma irradiation for mutation breeding of lentil were determined to be 70 Gy (L-2, L-8) and 100 Gy (L-C, L-9). We performed the comet assay to observe nuclear DNA damage induced by gamma-irradiation. In comet assay, a clear difference was identified over 100 Gy treatments. With increasing doses of gamma-ray in the range of 50 to 500 Gy, the rate of head DNA was decreased significantly from 97.5% to 81.6%. Tail length was consecutively increased from 1.9 μm to 17.4 μm. Our result provides basic information for construction of mutant pools in lentils

  20. Nuclear structure far above the yrast line

    International Nuclear Information System (INIS)

    Gaardhoeje, J.J.

    1985-01-01

    The phase space available for gamma ray spectroscopic studies has recently been extended significantly with the observation of gamma radiation produced in the decay of highly collective (isovector) giant dipole resonances (GDR), built on excited states of high spin, in nuclei produced in heavy ion induced fusion reactions. These gamma rays are predominantly emitted in competition with particles in the first few steps of the decay of compound systems and constitute an entirely new tool to study nuclei at excitation energies far above the yrast line. Some problems of current central interest are addressed. (Auth.)

  1. Gamma-ray bursts

    CERN Document Server

    Wijers, Ralph A M J; Woosley, Stan

    2012-01-01

    Cosmic gamma ray bursts (GRBs) have fascinated scientists and the public alike since their discovery in the late 1960s. Their story is told here by some of the scientists who participated in their discovery and, after many decades of false starts, solved the problem of their origin. Fourteen chapters by active researchers in the field present a detailed history of the discovery, a comprehensive theoretical description of GRB central engine and emission models, a discussion of GRB host galaxies and a guide to how GRBs can be used as cosmological tools. Observations are grouped into three sets from the satellites CGRO, BeppoSAX and Swift, and followed by a discussion of multi-wavelength observations. This is the first edited volume on GRB astrophysics that presents a fully comprehensive review of the subject. Utilizing the latest research, Gamma-ray Bursts is an essential desktop companion for graduate students and researchers in astrophysics.

  2. On-line and bulk analysis for the resource industries

    International Nuclear Information System (INIS)

    Lim, C.S.; Sowerby, B.D.; Tickner, J.R.; Madsen, I.C.

    2001-01-01

    Nuclear techniques are the basis of many CSIRO on-line and bulk analysis systems that are now widely used in the mineral and energy industries. The continuous analysis and rapid response of these systems have led to improved control of mining, processing and blending operations. This paper reviews recent developments in neutron, gamma-ray and X-ray techniques for on-line and bulk analysis by CSIRO Minerals including neutron techniques for the on-conveyor belt determination of the composition of cement raw meal, the on-line analysis of composition in pyrometallurgical applications, the on-conveyor belt determination of ash in coal, and the rapid and accurate determination of gold in bulk laboratory samples. The paper also discusses a new gamma-ray technique for the on-line determination of ash in coal and the application of X-ray diffraction techniques for the on-line determination of mineralogy in the cement industry

  3. On-line fuel and control rod integrity management in BWRs

    International Nuclear Information System (INIS)

    Larsson, Irina; Sihver, Lembit

    2011-01-01

    Surveillance of fuel and control rod integrity in a BWR core is essential to maintain a safe and reliable operation of a nuclear power plant. An accurate and prompt way to monitor fuel integrity in a reactor core during reactor operation is by using on-line measurements of the gamma emitting noble gas activities in the off-gas system. The integrity of control rods can be efficiently followed by on-line measurements of the helium (He) concentration in the off-gases. This method also gives information about fuel rod failures since He is used as a fill gas in the fuel rods. To survey fuel and control rod integrity during reactor operation, a system consisting of combined gamma and He on-line measurements in the off-gases should be used. Such a system can detect and follow the behavior of fuel and control rod failures. In addition, it can separate fuel failures from control rod failures since fuel rods contain both He and gamma emitting noble gases, while control rods only contain He. Moreover, the system is able to distinguish primary fuel failures from degradation of already existing ones. In this paper we present a combined system for on-line measurements of He and gamma emitting noble gases in the reactor off-gas system and measuring experiences from different BWRs. (author)

  4. THE 2010 VERY HIGH ENERGY {gamma}-RAY FLARE AND 10 YEARS OF MULTI-WAVELENGTH OBSERVATIONS OF M 87

    Energy Technology Data Exchange (ETDEWEB)

    Abramowski, A. [Institut fuer Experimentalphysik, Universitaet Hamburg, Luruper Chaussee 149, D 22761 Hamburg (Germany); Acero, F. [Laboratoire Univers et Particules de Montpellier, Universite Montpellier 2, CNRS/IN2P3, CC 72, Place Eugene Bataillon, F-34095 Montpellier Cedex 5 (France); Aharonian, F.; Bernloehr, K.; Bochow, A. [Max-Planck-Institut fuer Kernphysik, P.O. Box 103980, D 69029 Heidelberg (Germany); Akhperjanian, A. G. [National Academy of Sciences of the Republic of Armenia, 24 Marshall Baghramian Avenue, 0019 Yerevan (Armenia); Anton, G.; Balzer, A. [Physikalisches Institut, Universitaet Erlangen-Nuernberg, Erwin-Rommel-Str. 1, D 91058 Erlangen (Germany); Barnacka, A. [Nicolaus Copernicus Astronomical Center, ul. Bartycka 18, 00-716 Warsaw (Poland); Barres de Almeida, U. [Department of Physics, University of Durham, South Road, Durham DH1 3LE (United Kingdom); Becherini, Y. [Astroparticule et Cosmologie (APC), CNRS, Universite Paris 7 Denis Diderot, 10, rue Alice Domon et Leonie Duquet, F-75205 Paris Cedex 13 (France); Becker, J. [Institut fuer Theoretische Physik, Lehrstuhl IV: Weltraum und Astrophysik, Ruhr-Universitaet Bochum, D 44780 Bochum (Germany); Behera, B. [Landessternwarte, Universitaet Heidelberg, Koenigstuhl, D 69117 Heidelberg (Germany); Birsin, E. [Institut fuer Physik, Humboldt-Universitaet zu Berlin, Newtonstr. 15, D 12489 Berlin (Germany); Biteau, J. [Laboratoire Leprince-Ringuet, Ecole Polytechnique, CNRS/IN2P3, F-91128 Palaiseau (France); Boisson, C. [LUTH, Observatoire de Paris, CNRS, Universite Paris Diderot, 5 Place Jules Janssen, 92190 Meudon (France); Bolmont, J. [LPNHE, Universite Pierre et Marie Curie Paris 6, Universite Denis Diderot Paris 7, CNRS/IN2P3, 4 Place Jussieu, F-75252, Paris Cedex 5 (France); Bordas, P., E-mail: martin.raue@desy.de [Institut fuer Astronomie und Astrophysik, Universitaet Tuebingen, Sand 1, D 72076 Tuebingen (Germany); Collaboration: H.E.S.S. Collaboration; MAGIC Collaboration; VERITAS Collaboration; and others

    2012-02-20

    The giant radio galaxy M 87 with its proximity (16 Mpc), famous jet, and very massive black hole ((3 - 6) Multiplication-Sign 10{sup 9} M{sub Sun }) provides a unique opportunity to investigate the origin of very high energy (VHE; E > 100 GeV) {gamma}-ray emission generated in relativistic outflows and the surroundings of supermassive black holes. M 87 has been established as a VHE {gamma}-ray emitter since 2006. The VHE {gamma}-ray emission displays strong variability on timescales as short as a day. In this paper, results from a joint VHE monitoring campaign on M 87 by the MAGIC and VERITAS instruments in 2010 are reported. During the campaign, a flare at VHE was detected triggering further observations at VHE (H.E.S.S.), X-rays (Chandra), and radio (43 GHz Very Long Baseline Array, VLBA). The excellent sampling of the VHE {gamma}-ray light curve enables one to derive a precise temporal characterization of the flare: the single, isolated flare is well described by a two-sided exponential function with significantly different flux rise and decay times of {tau}{sup rise}{sub d} = (1.69 {+-} 0.30) days and {tau}{sup decay}{sub d} = (0.611 {+-} 0.080) days, respectively. While the overall variability pattern of the 2010 flare appears somewhat different from that of previous VHE flares in 2005 and 2008, they share very similar timescales ({approx}day), peak fluxes ({Phi}{sub >0.35TeV} {approx_equal} (1-3) Multiplication-Sign 10{sup -11} photons cm{sup -2} s{sup -1}), and VHE spectra. VLBA radio observations of 43 GHz of the inner jet regions indicate no enhanced flux in 2010 in contrast to observations in 2008, where an increase of the radio flux of the innermost core regions coincided with a VHE flare. On the other hand, Chandra X-ray observations taken {approx}3 days after the peak of the VHE {gamma}-ray emission reveal an enhanced flux from the core (flux increased by factor {approx}2; variability timescale <2 days). The long-term (2001-2010) multi-wavelength (MWL

  5. Analysis of gamma irradiated pepper constituents, 5

    International Nuclear Information System (INIS)

    Takagi, Kazuko; Okuyama, Tsuneo; Ishikawa, Toshihiro.

    1988-01-01

    Gamma irradiated peppers (10 krad, 100 krad, 1 Mrad) were analyzed by HPLC. The extraction method and HPLC conditions were same as the first report, that is, the extraction from pepper was performed by Automatic Air Hammer and the extracted samples were separated on a reversed phase C 8 column with a concave gradient from 0.1% trifluoro aceticacid (TFA) in water to 75% acetonitrile-0.1% TFA in water for 60 minutes and detected at 210 nm, 280 nm. It is difficult to compare with irradiated and unirradiated pepper constituents by their peak height or area. And the method of multi variant statistically analysis was introduced. The 'peak n area/peak n + 1 area' ratio was calculated by computer. Each peak area was accounted by integrator. The value of these ratio were called 'parameter'. Each chromatogram has 741 parameters calculated with 39 chromatographic peaks. And these parameters were abopted to the multi variant statiscally analysis. Comparison of constituents between irradiated pepper and unirradiated pepper was done by 741 parameters. The correlation of parameters between irradiated and unirradiated was investigated by use of computer. Some parameters of irradiated case were selected as which had no correlation with unirradiated case. That is to say these parameters were thought to be changed with gamma spectrum irradiation. By this method, Coumarin was identified as a changed component with gamma irradiation. (author)

  6. Bidirectional multi-optical line terminals incorporated converged WSN-PON network using M/M/1 queuing

    Science.gov (United States)

    Kumar, Love; Sharma, Vishal; Singh, Amarpal

    2017-12-01

    Wireless Sensor Networks (WSNs) have an assortment of application areas, for instance, civil, military, and video surveillance with restricted power resources and transmission link. To accommodate the massive traffic load in hefty sensor networks is another key issue. Subsequently, there is a necessity to backhaul the sensed information of such networks and prolong the transmission link to access the distinct receivers. Passive Optical Network (PON), a next-generation access technology, comes out as a suitable candidate for the convergence of the sensed data to the core system. The earlier demonstrated work with single-OLT-PON introduces an overloaded buffer akin to video surveillance scenarios. In this paper, to combine the bandwidth potential of PONs with the mobility capability of WSNs, the viability for the convergence of PONs and WSNs incorporating multi-optical line terminals is demonstrated to handle the overloaded OLTs. The existing M/M/1 queue theory with interleaving polling with adaptive cycle time as dynamic bandwidth algorithm is used to shun the probability of packets clash. Further, the proposed multi-sink WSN and multi-OLT PON converged structure is investigated in bidirectional mode analytically and through computer simulations. The observations establish the proposed structure competent to accommodate the colossal data traffic through less time consumption.

  7. Monitoring, controlling and safeguarding radiochemical streams at spent fuel reprocessing facilities with optical and gamma-ray spectroscopic methods

    International Nuclear Information System (INIS)

    Schwantes, J.M.; Bryan, S.A.; Orton, C.R.; Levitskaia, T.G.; Fraga, C.G.

    2013-01-01

    The International Atomic Energy Agency (IAEA) has established international safeguards standards for fissionable material at spent fuel reprocessing plants to ensure that significant quantities of weapons-usable nuclear material are not diverted from these facilities. For large throughput nuclear facilities, it is difficult to satisfy the IAEA safeguards accountancy goal for detection of abrupt diversion. Currently, methods to verify material control and accountancy (MCA) at these facilities require time-consuming and resource intensive destructive assay (DA). Leveraging new on-line non-destructive assay (NDA) process monitoring techniques in conjunction with the traditional and highly precise DA methods may provide an additional measure to nuclear material accountancy which would potentially result in a more timely, cost-effective and resource efficient means for safeguards verification at such facilities. By monitoring process control measurements (e.g. flowrates, temperatures, or concentrations of reagents, products or wastes), abnormal plant operations can be detected. Pacific Northwest National Laboratory (PNNL) is developing on-line NDA process monitoring technologies based upon gamma-ray and optical spectroscopic measurements to potentially reduce the time and resource burden associated with current techniques. The Multi-Isotope Process (MIP) Monitor uses gamma spectroscopy and multivariate analysis to identify off-normal conditions in process streams. The spectroscopic monitor continuously measures chemical compositions of the process streams including actinide metal ions (U, Pu, Np), selected fission products, and major stable flowsheet reagents using UV-Vis, Near IR and Raman spectroscopy. Multi-variate analysis is also applied to the optical measurements in order to quantify concentrations of analytes of interest within a complex array of radiochemical streams. This paper will provide an overview of these methods and reports on-going efforts to develop

  8. Automatic storing of single gamma spectra on magnetic tape. Programs LONGO, DIRE; Automatizacion del almacenamiento en cinta magnetica de espectros gamma directos. Programas LONGO, DIRE

    Energy Technology Data Exchange (ETDEWEB)

    Los Arcos Merino, J M

    1978-07-01

    The program LONGO provides the block size and the block number in a binary file on magnetic tape. It has been applied to analyse the structure of the nine-track magnetic tapes storing single or coincidence gamma spectra files, recorded in octet form by a MULTI-8 minicomputer in the Nuclear Spectrometry Laboratory of J.E.N. Then the program DIRE has been written to transform the single gamma spectra into a new FASTRAND disk file, storing the information in-36 bit words. A copy of this file is obtained on magnetic tape and the single gamma spectra are then available by standard FORTRAN V reading sentences. (Author) 3 refs.

  9. The Improvement of Atomita-4 Rice Variety Through Gamma Rays Irradiation of F1 Seeds from Atomita-4/Ir-64 Crossing

    International Nuclear Information System (INIS)

    Lilik Harsanti; Mugiono

    2004-01-01

    Atom ita-4 rice variety was crossed with IR-64 variety in the greenhouse at the Center for Application of Isotopes and Radiation-Batan, Pasar jumat in the wet season of 1994/1995. F 1 Seeds derived from Atomita-4/IR-64 crossing were irradiated by gamma rays at of 0.2 kGy dose. F 1 seeds were grown to obtain F 2 M 2 seed, and then selection of pedigree were carried out at F 2 generation. Six mutants lines were obtained purified and screened on biotypes 1, 2 and 3 brown plant hopper and bacterial leaf blight resistance by IRRI standard screening methods. The six mutant lines were tested for their potential yield at Pusakanegara and then continued tested in yield multi location test at several locations in Indonesia. Results of the screening test to brown plant hopper showed that two mutant lines Obs-1653/PsJ and Obs-1656/PsJ were resistant to biotype 1, biotype 2 and medium resistant to biotype 3. Obs-1653/PsJ and Obs-1656/PsJ also showed resistance to bacterial leaf blight strain 3 and medium resistance to strain 4. Results in the yield multi location test showed that Obs-1653/PsJ and Obs-1656/PsJ have highest yielding potential compared to IR-64 and Memberamo varieties. Those two mutant lines were released as new varieties under the name Merauke and Kahayan in 2001 and 2003 respectively. (author)

  10. Fluorescent L-radiation and the. gamma. -radiation of ionium

    Energy Technology Data Exchange (ETDEWEB)

    Riou, M

    1949-02-21

    Irene Curie, Compt. rend. 227, 1225(1948), has shown that the ..gamma..-radiation of ionium is accompanied by a soft radiation that can be identified with the fluorescent L-lines of radium. The present author submitted these radiations to a further study, using as a source a ionium--thorium mixture, (100 mg of hydrate), containing 9% ionium. The Geiger--Mueller counters had 5 mg/cm/sup 2/ aluminum ends and were filled with alcohol + xenon at 10-21 cm Hg. The absorption curves in Cu, Mo, and Ag showed that the energy of the soft radiation was about 14 keV. For the separation of lines, the selective absorption was determined in elements from Z = 28 to Z = 53. The results confirmed the attribution of the spectrum to the L-radiation of Ra. Similar measurements on radioactinium revealed the same lines with approximately the same intensities. In both cases a radium isotope is formed: /sub 90/Th/sup 230/(Io) ..-->.. /sub 88/Ra/sup 226/ ..-->.. ..cap alpha.., /sub 90/Th/sup 227/ (RaAc) ..-->.. /sub 88/Ra/sup 223/ (AcX) + ..cap alpha... The identity of the spectra shows that the atomic number of the formed atom alone determines the L-spectrum, and that in both cases the L level is excited as a result of an internal conversion of ..gamma..-lines: the line 68 keV in the case of ionium, eight lines 26-100 keV in that of radioactinium. On the basis of the intensities found, the relative numbers of photons corresponding to the levels L/sub I/, L/sub II/, and L/sub III/ could be calculated; they are L/sub I/:L/sub II/:L/sub III/ = 50:20:26. The ..gamma..-rays of ionium, as determined from the absorption in Cu, Ta, and Pb, are 68 and 200 kev. By assuming that the efficiency of the counters is equal to 1 - exp (-m..mu../rho), (where m is the efficient superficial mass of xenon, and ..mu../rho is the absorption coefficient in xenon), the intensities of the L- and ..gamma..-radiations of ionium can be given in terms of numbers of quanta per 100 disintegrations.

  11. Modulation of interferon-gamma-induced HLA-DR expression on the human keratinocyte cell line SCC-13 by ultraviolet radiation

    International Nuclear Information System (INIS)

    Khan, I.U.; Boehm, K.D.; Elmets, C.A.

    1993-01-01

    Cell surface expression of major histocompatibility determinants on epidermal keratinocytes is a characteristic feature of a number of inflammatory dermatoses and in all likelihood is caused by diffusion of human leukocyte antigen (HLA)-DR-inducing cytokines from cells present in the dermal mononuclear cell infiltrate. Many of these same disorders respond to ultraviolet (UV) radiation phototherapy. Using the human SCC-13 keratinocyte cell line as a model, UV radiation was found to inhibit interferon-gamma-induced HLA-DR expression. Inhibition correlated closely with decreased steady-state levels of HLA-DR mRNA. These findings provide evidence that the therapeutic effect of UV radiation phototherapy may be mediated by its capacity to down-regulate cytokine-induced keratinocyte HLA-DR expression. (Author)

  12. On-Line High Dose-Rate Gamma Ray Irradiation Test of the CCD/CMOS Cameras

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jai Wan; Jeong, Kyung Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    In this paper, test results of gamma ray irradiation to CCD/CMOS cameras are described. From the CAMS (containment atmospheric monitoring system) data of Fukushima Dai-ichi nuclear power plant station, we found out that the gamma ray dose-rate when the hydrogen explosion occurred in nuclear reactors 1{approx}3 is about 160 Gy/h. If assumed that the emergency response robot for the management of severe accident of the nuclear power plant has been sent into the reactor area to grasp the inside situation of reactor building and to take precautionary measures against releasing radioactive materials, the CCD/CMOS cameras, which are loaded with the robot, serve as eye of the emergency response robot. In the case of the Japanese Quince robot system, which was sent to carry out investigating the unit 2 reactor building refueling floor situation, 7 CCD/CMOS cameras are used. 2 CCD cameras of Quince robot are used for the forward and backward monitoring of the surroundings during navigation. And 2 CCD (or CMOS) cameras are used for monitoring the status of front-end and back-end motion mechanics such as flippers and crawlers. A CCD camera with wide field of view optics is used for monitoring the status of the communication (VDSL) cable reel. And another 2 CCD cameras are assigned for reading the indication value of the radiation dosimeter and the instrument. In the preceding assumptions, a major problem which arises when dealing with CCD/CMOS cameras in the severe accident situations of the nuclear power plant is the presence of high dose-rate gamma irradiation fields. In the case of the DBA (design basis accident) situations of the nuclear power plant, in order to use a CCD/CMOS camera as an ad-hoc monitoring unit in the vicinity of high radioactivity structures and components of the nuclear reactor area, a robust survivability of this camera in such intense gamma-radiation fields therefore should be verified. The CCD/CMOS cameras of various types were gamma irradiated at a

  13. Gamma-to-electron magnetic spectrometer (GEMS): An energy-resolved {gamma}-ray diagnostic for the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y.; Herrmann, H. W.; Mack, J. M.; Young, C. S.; Barlow, D. B.; Schillig, J. B.; Sims, J. R. Jr.; Lopez, F. E.; Mares, D.; Oertel, J. A.; Hayes-Sterbenz, A. C. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Hilsabeck, T. J.; Wu, W. [General Atomics, PO Box 85608, San Diego, California 92186 (United States); Moy, K. [National Security Technologies, Special Technologies Laboratory, Santa Barbara, California 93111 (United States); Stoeffl, W. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2012-10-15

    The gamma-to-electron magnetic spectrometer, having better than 5% energy resolution, is proposed to resolve {gamma}-rays in the range of E{sub o}{+-} 20% in single shot, where E{sub o} is the central energy and is tunable from 2 to 25 MeV. Gamma-rays from inertial confinement fusion implosions interact with a thin Compton converter (e.g., beryllium) located at approximately 300 cm from the target chamber center (TCC). Scattered electrons out of the Compton converter enter an electromagnet placed outside the NIF chamber (approximately 600 cm from TCC) where energy selection takes place. The electromagnet provides tunable E{sub o} over a broad range in a compact manner. Energy resolved electrons are measured by an array of quartz Cherenkov converters coupled to photomultipliers. Given 100 detectable electrons in the energy bins of interest, 3 Multiplication-Sign 10{sup 14} minimum deuterium/tritium (DT) neutrons will be required to measure the 4.44 MeV {sup 12}C {gamma}-rays assuming 200 mg/cm{sup 2} plastic ablator areal density and 3 Multiplication-Sign 10{sup 15} minimum DT neutrons to measure the 16.75 MeV DT {gamma}-ray line.

  14. Primary radioactivity standardization and gamma intensities determination of {sup 124}Sb

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-04-21

    A solution containing {sup 124}Sb was primarily standardized by the 4{pi}{beta}-{gamma} coincidence and anticoincidence extrapolation methods in the frame of the EUROMET 907 international comparison organized by Laboratoire National Henri Bequerel (LNHB)/France, in 2007. The main purposes of this exercise are the improvement in the uncertainties on the gamma-ray emission intensities and they clarify the discrepancies verified among the intensity values for many weak gamma rays reported in the literature. In this work the results of the activity obtained were used to determine the absolute and relative gamma-ray intensities using a planar and coaxial HPGe detectors calibrated by {sup 152}Eu and {sup 116m}Ho multi-gamma standard sources covering the energy range from 20 to 1408 keV. Additionally the half-life of {sup 124}Sb was determined following the decay of a solution of {sup 124}Sb contained in a glass ampoule over a period of three half-lives using two 4{pi}{gamma} ionization chambers.

  15. Gamma Radiation-Induced Mutations in Soybeans

    International Nuclear Information System (INIS)

    Smutkupt, S.

    1998-01-01

    The main objective of soybean radiation experiments was to create genetic variability in soybeans of various cultivars, mutants and mutation-derived lines with the aim of producing superior breeding lines with resistance to soybean rust (Phakopsora pachyhrizi Syd.) It took altogether 12 generations over six years after gamma irradiation if soybean seeds to produce the best resistant line (81-1-038) which a variety could be developed from it. This Line 81-1-038 showed a very good specific resistance to soybean rust, Thai race 2 and moderately resistance to Thai race 1. In the rainy season of 1985, Line 81-1-038 out yielded S.J.4 (a mother line) by 868 kg/ha in a yield trail at Suwan Farm, Pak Chong, Nakorn Rajchasima. This soybean rust mutant was later named D oi Kham

  16. Improved amylose content of rice (IR72) induced through gamma radiation

    International Nuclear Information System (INIS)

    Barrida, Adelaida C.; Rivera, Faye G.; Manrique, Mary Jayne C.; Dimaano, Arvin O.; Costimiano, Eduardo C.

    2015-01-01

    In general grain quality and quality preferences vary across rice growing countries and regions. Filipinos preferres translucent, well milled, long grain rice with aroma and minimal broken grains which is soft after cooling. The amylose content of rice starch is a major eating quality factor. The aim of this study is to develop rice mutants with good eating quality and low to intermediate amylose content through induced mutation using gamma radiation. Low to intermediate amylose content in rice were identified and selected among the advance generation lines irradiated with 200 and 300Gy dose of gamma radiation. Screening was done using qualitative method (Iodine staining method). Selected lines were analyzed quantitatively, to determine the percent amylose content. Percent amylose were group to several categories where; 0-6% is waxy, 6-12% is very low, 12-18% is low, 18-24% is intermediate and >25% is high. Results were further confirmed using molecular marker technique by looking at the waxy gene which code for granule bound starch synthase I (GBSSI) and controls amylose content in rice. Among the 30 lines selcted and anaylzes, 2 lines were confirmed to have a gene base mutation with a low to intermediate amylose content. Thus, induced mutation using gamma radiation has successfully improved amylose content in rice (IR72). (author)

  17. Open high-level data formats and software for gamma-ray astronomy

    Science.gov (United States)

    Deil, Christoph; Boisson, Catherine; Kosack, Karl; Perkins, Jeremy; King, Johannes; Eger, Peter; Mayer, Michael; Wood, Matthew; Zabalza, Victor; Knödlseder, Jürgen; Hassan, Tarek; Mohrmann, Lars; Ziegler, Alexander; Khelifi, Bruno; Dorner, Daniela; Maier, Gernot; Pedaletti, Giovanna; Rosado, Jaime; Contreras, José Luis; Lefaucheur, Julien; Brügge, Kai; Servillat, Mathieu; Terrier, Régis; Walter, Roland; Lombardi, Saverio

    2017-01-01

    In gamma-ray astronomy, a variety of data formats and proprietary software have been traditionally used, often developed for one specific mission or experiment. Especially for ground-based imaging atmospheric Cherenkov telescopes (IACTs), data and software are mostly private to the collaborations operating the telescopes. However, there is a general movement in science towards the use of open data and software. In addition, the next-generation IACT instrument, the Cherenkov Telescope Array (CTA), will be operated as an open observatory. We have created a Github organisation at https://github.com/open-gamma-ray-astro where we are developing high-level data format specifications. A public mailing list was set up at https://lists.nasa.gov/mailman/listinfo/open-gamma-ray-astro and a first face-to-face meeting on the IACT high-level data model and formats took place in April 2016 in Meudon (France). This open multi-mission effort will help to accelerate the development of open data formats and open-source software for gamma-ray astronomy, leading to synergies in the development of analysis codes and eventually better scientific results (reproducible, multi-mission). This write-up presents this effort for the first time, explaining the motivation and context, the available resources and process we use, as well as the status and planned next steps for the data format specifications. We hope that it will stimulate feedback and future contributions from the gamma-ray astronomy community.

  18. MERCURE-3, Gamma Attenuation by Line-of-Flight in 3-D Heterogeneous Geometry

    International Nuclear Information System (INIS)

    Devillers, C.; Szondi, Egon J.

    1995-01-01

    1 - Nature of physical problem solved: MERCURE-3/PC performs three- dimensional gamma shielding calculations around extended gamma sources. These may be even non-homogeneous. 2 - Method of solution: The algorithm of the code is the point kernel integration model combined with buildup calculations. The geometry can be described analytically using linear and quadratic surfaces of any type. A standard gamma cross section library is provided with the code. 3 - Restrictions on the complexity of the problem: To make possible the solution of large problems, all the problem size-dependent arrays are declared using symbolic constants. The default values are sufficient for most of the practical problems (e.g. 100 space elements; 100 equations; 300 surface elements; 40 materials; 25 energy groups, etc.); the code uses in this case only 200-250 Kbytes of memory, depending on the compiler used. If the problem is very large, the symbolic constants have to be modified, and the code has to be compiled using the Lahey F77L3 (protected mode) compiler

  19. Multi-turn multi-gap transmission line resonators - Concept, design and first implementation at 4.7T and 7T.

    Science.gov (United States)

    Frass-Kriegl, Roberta; Laistler, Elmar; Hosseinnezhadian, Sajad; Schmid, Albrecht Ingo; Moser, Ewald; Poirier-Quinot, Marie; Darrasse, Luc; Ginefri, Jean-Christophe

    2016-12-01

    A novel design scheme for monolithic transmission line resonators (TLRs) is presented - the multi-turn multi-gap TLR (MTMG-TLR) design. The MTMG-TLR design enables the construction of TLRs with multiple turns and multiple gaps. This presents an additional degree of freedom in tuning self-resonant TLRs, as their resonance frequency is fully determined by the coil geometry (e.g. diameter, number of turns, conductor width, etc.). The novel design is evaluated at 4.7T and 7T by simulations and experiments, where it is demonstrated that MTMG-TLRs can be used for MRI, and that the B 1 distribution of MTMG-TLRs strongly depends on the number and distribution of turns. A comparison to conventional loop coils revealed that the B 1 performance of MTMG-TLRs is comparable to a loop coil with the same mean diameter; however, lower 10g SAR values were found for MTMG-TLRs. The MTMG-TLR design is expected to bring most benefits at high static field, where it allows for independent size and frequency selection, which cannot be achieved with standard TLR design. However, it also enables more accurate geometric optimization at low static field. Thereby, the MTMG-TLR design preserves the intrinsic advantages of TLRs, i.e. mechanical flexibility, high SAR efficiency, mass production, and coil miniaturization. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  20. Sequential multi-nuclide emission rate estimation method based on gamma dose rate measurement for nuclear emergency management

    International Nuclear Information System (INIS)

    Zhang, Xiaole; Raskob, Wolfgang; Landman, Claudia; Trybushnyi, Dmytro; Li, Yu

    2017-01-01

    Highlights: • Sequentially reconstruct multi-nuclide emission using gamma dose rate measurements. • Incorporate a priori ratio of nuclides into the background error covariance matrix. • Sequentially augment and update the estimation and the background error covariance. • Suppress the generation of negative estimations for the sequential method. • Evaluate the new method with twin experiments based on the JRODOS system. - Abstract: In case of a nuclear accident, the source term is typically not known but extremely important for the assessment of the consequences to the affected population. Therefore the assessment of the potential source term is of uppermost importance for emergency response. A fully sequential method, derived from a regularized weighted least square problem, is proposed to reconstruct the emission and composition of a multiple-nuclide release using gamma dose rate measurement. The a priori nuclide ratios are incorporated into the background error covariance (BEC) matrix, which is dynamically augmented and sequentially updated. The negative estimations in the mathematical algorithm are suppressed by utilizing artificial zero-observations (with large uncertainties) to simultaneously update the state vector and BEC. The method is evaluated by twin experiments based on the JRodos system. The results indicate that the new method successfully reconstructs the emission and its uncertainties. Accurate a priori ratio accelerates the analysis process, which obtains satisfactory results with only limited number of measurements, otherwise it needs more measurements to generate reasonable estimations. The suppression of negative estimation effectively improves the performance, especially for the situation with poor a priori information, where it is more prone to the generation of negative values.

  1. Sequential multi-nuclide emission rate estimation method based on gamma dose rate measurement for nuclear emergency management

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiaole, E-mail: zhangxiaole10@outlook.com [Institute for Nuclear and Energy Technologies, Karlsruhe Institute of Technology, Karlsruhe, D-76021 (Germany); Institute of Public Safety Research, Department of Engineering Physics, Tsinghua University, Beijing, 100084 (China); Raskob, Wolfgang; Landman, Claudia; Trybushnyi, Dmytro; Li, Yu [Institute for Nuclear and Energy Technologies, Karlsruhe Institute of Technology, Karlsruhe, D-76021 (Germany)

    2017-03-05

    Highlights: • Sequentially reconstruct multi-nuclide emission using gamma dose rate measurements. • Incorporate a priori ratio of nuclides into the background error covariance matrix. • Sequentially augment and update the estimation and the background error covariance. • Suppress the generation of negative estimations for the sequential method. • Evaluate the new method with twin experiments based on the JRODOS system. - Abstract: In case of a nuclear accident, the source term is typically not known but extremely important for the assessment of the consequences to the affected population. Therefore the assessment of the potential source term is of uppermost importance for emergency response. A fully sequential method, derived from a regularized weighted least square problem, is proposed to reconstruct the emission and composition of a multiple-nuclide release using gamma dose rate measurement. The a priori nuclide ratios are incorporated into the background error covariance (BEC) matrix, which is dynamically augmented and sequentially updated. The negative estimations in the mathematical algorithm are suppressed by utilizing artificial zero-observations (with large uncertainties) to simultaneously update the state vector and BEC. The method is evaluated by twin experiments based on the JRodos system. The results indicate that the new method successfully reconstructs the emission and its uncertainties. Accurate a priori ratio accelerates the analysis process, which obtains satisfactory results with only limited number of measurements, otherwise it needs more measurements to generate reasonable estimations. The suppression of negative estimation effectively improves the performance, especially for the situation with poor a priori information, where it is more prone to the generation of negative values.

  2. MoonBEAM: Gamma-Ray Burst Detectors on SmallSAT

    Science.gov (United States)

    Hui, C. M.; Briggs, M. S.; Goldstein, A. M.; Jenke, P. A.; Kocevski, D.; Wilson-Hodge, C. A.

    2018-01-01

    Moon Burst Energetics All-sky Monitor (MoonBEAM) is a CubeSat concept of deploying gamma-ray detectors in cislunar space to improve localization precision for gamma-ray bursts by utilizing the light travel time difference between a spacecraft in Earth and cislunar orbit. MoonBEAM is designed with high TRL components to be flight ready. This instrument would probe the extreme processes in cosmic collision of compact objects and facilitate multi-messenger time-domain astronomy to explore the end of stellar life cycles and black hole formations.

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

    International Nuclear Information System (INIS)

    Beuermann, K.P.

    1974-01-01

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

  4. Stokes line width

    International Nuclear Information System (INIS)

    Nikiskov, A.I.; Ritus, V.I.

    1993-01-01

    The concept of Stokes line width is introduced for the asymptotic expansions of functions near an essential singularity. Explicit expressions are found for functions (switching functions) that switch on the exponentially small terms for the Dawson integral, Airy function, and the gamma function. A different, more natural representation of a function, not associated with expansion in an asymptotic series, in the form of dominant and recessive terms is obtained by a special division of the contour integral which represents the function into contributions of higher and lower saddle points. This division leads to a narrower, natural Stokes line width and a switching function of an argument that depends on the topology of the lines of steepest descent from the saddle point

  5. Structural investigation on gamma-irradiated polyacrylamide ...

    Indian Academy of Sciences (India)

    Polyacrylamide hydrogels; small-angle neutron scattering; UV–visible spectra; gamma ... dynamic light scattering and electron microscopy techniques and also by equilibrium swelling theory [10,11]. Here, for the first time, we report the effect of γ-irradiation on inhomogeneities and cor- ... The solid lines are guides to the eye.

  6. Linear polarization measurements at H. beta. of early-type emission line stars

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, D; McLean, I S [Glasgow Univ. (UK)

    1976-02-01

    Linear polarization measurements across the H..beta.. emission lines of the stars ..gamma.. Cas, zeta Tau and 48 Per are presented. For the first two stars there is a marked reduction of the polarization at the centre of the line and for ..gamma.. Cas, this varies from night to night. During the H..beta.. observations of zeta Tau, a change of polarization over tens of minutes was indicated in a monitor channel tuned to the continuum on the blue side of H..beta... For the fainter star, 48 Per, the uncertainties of the polarimetry were increased in relation to ..gamma.. Cas and zeta Tau by a factor of about two and at this precision, no differential effects across the line were recorded. Observations of ..cap alpha.. Cyg are also given to demonstrate the reliability of the polarimeter.

  7. Effect of gamma irradiation on nutritional value of dry field beans (Phaseolus vulgaris) and variability in nutritional value of varieties and breeding lines of dry field beans and peas for chicks

    International Nuclear Information System (INIS)

    Reddy, S.J.

    1978-01-01

    Experiments were conducted with day-old broiler type chicks to study the effect of a cobalt-60 source of gamma irradiation and autoclaving on nutritional value of dry field beans (Phaseolus vulgaris). The variability in nutritional value of varieties and breeding lines of dry field beans and peas was also studied. Total protein (N x 6.25) was not changed appreciably by gamma irradiation (21 Mrad cobalt-60) and autoclaving but solubility in water was decreased. In vitro enzymic digestibility of irradiated bean protein was increased by pepsin alone and with a mixture of trypsin, chymotrypsin and peptidase. The nutritional value of all varieties of beans, based on chick growth, was significantly improved by gamma irradiation. The irradiated treatment of beans increased nitrogen retention by chicks and decreased uric acid nitrogen excretion in relation to nitrogen intake

  8. Explicit calculation of multi-fold contour integrals of certain ratios of Euler gamma functions. Pt. 1

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Ivan [Valparaiso Univ. (Chile). Inst. de Fisica y Astronomia; Kniehl, Bernd A. [Hamburg Univ. (Germany). II. Inst. fuer Theoretische Physik; Kondrashuk, Igor [Univ. del Bio-Bio, Chillan (Chile). Dept. de Ciencias Basicas; Notte-Cuello, Eduardo A. [La Serena Univ. (Chile). Dept. de Matematicas; Parra-Ferrada, Ivan [Talca Univ. (Chile). Inst. de Matematica y Fisica; Rojas-Medar, Marko A. [Univ. de Tarapaca, Arica (Chile). Inst. de Alta Investigacion

    2016-12-15

    In this paper we proceed to study properties of Mellin-Barnes (MB) transforms of Usyukina-Davydychev (UD) functions. In our previous papers [Nuclear Physics B 870 (2013) 243], [Nuclear Physics B 876 (2013) 322] we showed that multi-fold Mellin-Barnes (MB) transforms of Usyukina-Davydychev (UD) functions may be reduced to two-fold MB transforms and that the higher-order UD functions were obtained in terms of a differential operator by applying it to a slightly modified first UD function. The result is valid in d=4 dimensions and its analog in d=4-2ε dimensions exits too [Theoretical and Mathematical Physics 177 (2013) 1515]. In [Nuclear Physics B 870 (2013) 243] the chain of recurrent relations for analytically regularized UD functions was obtained implicitly by comparing the left hand side and the right hand side of the diagrammatic relations between the diagrams with different loop orders. In turn, these diagrammatic relations were obtained due to the method of loop reductions for the triangle ladder diagrams proposed in 1983 by Belokurov and Usyukina. Here we reproduce these recurrent relations by calculating explicitly via Barnes lemmas the contour integrals produced by the left hand sides of the diagrammatic relations. In such a way we explicitly calculate a family of multi-fold contour integrals of certain ratios of Euler gamma functions. We make a conjecture that similar results for the contour integrals are valid for a wider family of smooth functions which includes the MB transforms of UD functions.

  9. Comparison of the radiosensitivity of three goldfish cell lines using short term endpoints

    Energy Technology Data Exchange (ETDEWEB)

    Mitani, H. (Tokyo Univ. (Japan). Faculty of Science)

    1984-06-01

    The induction and rejoining of DNA strand breaks after ..gamma..-irradiation in three goldfish (Carassius auratus) cell lines with different sensitivities to the lethal effect of ..gamma..-rays has been studied by the DNA strand separation method using hydroxylapatite chromatography. The induction and rejoining of DNA strand breaks was similar in all cell lines. There was also little difference in the degree of inhibition of DNA synthesis immediately after irradiation. However, the rank orders of the durations of division delay and the radiosensitivities of the three cell lines were the same.

  10. A Gamma Memory Neural Network for System Identification

    Science.gov (United States)

    Motter, Mark A.; Principe, Jose C.

    1992-01-01

    A gamma neural network topology is investigated for a system identification application. A discrete gamma memory structure is used in the input layer, providing delayed values of both the control inputs and the network output to the input layer. The discrete gamma memory structure implements a tapped dispersive delay line, with the amount of dispersion regulated by a single, adaptable parameter. The network is trained using static back propagation, but captures significant features of the system dynamics. The system dynamics identified with the network are the Mach number dynamics of the 16 Foot Transonic Tunnel at NASA Langley Research Center, Hampton, Virginia. The training data spans an operating range of Mach numbers from 0.4 to 1.3.

  11. A multi attribute decision making method for selection of optimal assembly line

    Directory of Open Access Journals (Sweden)

    B. Vijaya Ramnath

    2011-01-01

    Full Text Available With globalization, sweeping technological development, and increasing competition, customers are placing greater demands on manufacturers to increase quality, flexibility, on time delivery of product and less cost. Therefore, manufacturers must develop and maintain a high degree of coherence among competitive priorities, order winning criteria and improvement activities. Thus, the production managers are making an attempt to transform their organization by adopting familiar and beneficial management philosophies like cellular manufacturing (CM, lean manufacturing (LM, green manufacturing (GM, total quality management (TQM, agile manufacturing (AM, and just in time manufacturing (JIT. The main objective of this paper is to propose an optimal assembly method for an engine manufacturer’s assembly line in India. Currently, the Indian manufacturer is following traditional assembly method where the raw materials for assembly are kept along the sideways of conveyor line. It consumes more floor space, more work in process inventory, more operator's walking time and more operator's walking distance per day. In order to reduce the above mentioned wastes, lean kitting assembly is suggested by some managers. Another group of managers suggest JIT assembly as it consumes very less inventory cost compared to other types of assembly processes. Hence, a Multi-attribute decision making model namely analytical hierarchy process (AHP is applied to analyse the alternative assembly methods based on various important factors.

  12. GBM Observations of Terrestrial Gamma-Ray Flashes

    Science.gov (United States)

    Briggs, M. S.; Fishman, G. J.; Connaughton, V.; Bhat, P. N.; Paciesas, W. S.; Preece, R. D.; Wilson-Hodge, C.; Chaplin, V. L.; Kippen, R. M.; vonKienlin, A.; hide

    2010-01-01

    The TGF detection rate of Gamma-ray Burst Monitor (GBM) has been increased twice since launch. The most recent improvement is from a new operating mode in which data for individual photons are down-linked for selected portions of the orbit, enabling a more sensitive ground-based search for TGFs. The new search has increased the TGF detection rate and is finding TGFs more than five times fainter than the TGFs of the previous GBM sample. We summarize the properties of the original GBM TGF sample and compare to the less intense TGFs now being detected. In addition to gamma-ray TGFs, GBM is observing distant TGFs from the propagation of charged particles along geomagnetic field lines. Strong 511 keV annihilation lines have been observed, demonstrating that both electrons and positrons are present in the particle beams. Spectral fits to these electron/positron TGFs will be shown.

  13. Response of STFZ diode as on-line gamma dosimeter in radiation processing

    International Nuclear Information System (INIS)

    Camargo, Fabio de; Goncalves, Josemary A.C.; Pascoalino, Kelly C.; Bueno, Carmen C.; Tuominen, Eija; Tuovinen, Esa; Haerkoenen, Jaakko

    2009-01-01

    In this work, it is presented the results obtained with this rad-hard STFZ silicon diode as a high-dose gamma dosimeter. This device is a p + /n/n + junction diode, made on FZ Si wafer manufactured by Okmetic Oyj., Vantaa, Finland and processed by the Microelectronics Center of Helsinki University of Technology. The results obtained about the photocurrent registered and total charge accumulated on the diode as a function of the total absorbed dose are presented. The diodes' response showed a significant saturation effect for total absorbed doses higher than approximately 15 kGy. To reduce this effect, some STFZ samples have been pre-irradiated with gamma rays at accumulated dose of 700 kGy in order to saturate the trap production in the diode's sensitive volume. (author)

  14. Compact FEL-driven inverse compton scattering gamma-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Placidi, M. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Di Mitri, S., E-mail: simone.dimitri@elettra.eu [Elettra - Sincrotrone Trieste S.C.p.A., 34149 Basovizza, Trieste (Italy); Pellegrini, C. [SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); University of California, Los Angeles, CA 90095 (United States); Penn, G. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2017-05-21

    Many research and applications areas require photon sources capable of producing gamma-ray beams in the multi-MeV energy range with reasonably high fluxes and compact footprints. Besides industrial, nuclear physics and security applications, a considerable interest comes from the possibility to assess the state of conservation of cultural assets like statues, columns etc., via visualization and analysis techniques using high energy photon beams. Computed Tomography scans, widely adopted in medicine at lower photon energies, presently provide high quality three-dimensional imaging in industry and museums. We explore the feasibility of a compact source of quasi-monochromatic, multi-MeV gamma-rays based on Inverse Compton Scattering (ICS) from a high intensity ultra-violet (UV) beam generated in a free-electron laser by the electron beam itself. This scheme introduces a stronger relationship between the energy of the scattered photons and that of the electron beam, resulting in a device much more compact than a classic ICS for a given scattered energy. The same electron beam is used to produce gamma-rays in the 10–20 MeV range and UV radiation in the 10–15 eV range, in a ~4×22 m{sup 2} footprint system.

  15. High Affinity IgE-Fc Receptor alpha and gamma Subunit Interactions

    International Nuclear Information System (INIS)

    Rashid, A.; Housden, J. E. M.; Sabban, S.; Helm, B.

    2014-01-01

    Objective: To explore the relationships between the subunits (alpha, beta and gamma) of the high affinity IgE receptor (Fc and RI) and its ability to mediate transmembrane signaling. Study Design: Experimental study. Place and Duration of Study: Department of Molecular Biology and Biotechnology, University of Sheffield, UK, from 2008 to 2009. Methodology: The approach employed was to create a chimera (human alpha-gamma-gamma) using the extracellular (EC) domain of the human high affinity IgE receptor. The alpha subunit (huFc and RIalpha) of IgE receptor was spliced onto the rodent gamma TM and cytoplasmic domain (CD). This was transfected into the Rat Basophilic Leukemia cell line in order to assess the possibility of selectively activating cells transfected with this single pass construct for antigen induced mediator release. Results: The RBLs cell lines transfected with the huFc and RIalpha/gamma/gamma cDNA constructs were assessed for the cell surface expression of the huFc and RIalpha subunit and the response to the antigenic stimulus by looking for degranulation and intracellular Ca2+ mobilisation. The results obtained showed the absence of huFc and RIalpha subunit expression on the surface of transfected cells as seen by flowcytometric studies, beta-hexosaminidase assays and intracellular calcium mobilisation studies. Conclusion: In the present study the grounds for non-expression of huFc and RIalpha/gamma/gamma cDNA remains elusive but may be due to the fact that the human-rodent chimeric receptors are assembled differently than the endogenous rodent receptors as seen in study in which COS 7 cells were transfected with human/rat chimeric complexes. (author)

  16. A new multi-line cusp magnetic field plasma device (MPD) with variable magnetic field

    Science.gov (United States)

    Patel, A. D.; Sharma, M.; Ramasubramanian, N.; Ganesh, R.; Chattopadhyay, P. K.

    2018-04-01

    A new multi-line cusp magnetic field plasma device consisting of electromagnets with core material has been constructed with a capability to experimentally control the relative volume fractions of magnetized to unmagnetized plasma volume as well as accurate control on the gradient length scales of mean density and temperature profiles. Argon plasma has been produced using a hot tungsten cathode over a wide range of pressures 5 × 10-5 -1 × 10-3 mbar, achieving plasma densities ranging from 109 to 1011 cm-3 and the electron temperature in the range 1-8 eV. The radial profiles of plasma parameters measured along the non-cusp region (in between two consecutive magnets) show a finite region with uniform and quiescent plasma, where the magnetic field is very low such that the ions are unmagnetized. Beyond that region, both plasma species are magnetized and the profiles show gradients both in temperature and density. The electrostatic fluctuation measured using a Langmuir probe radially along the non-cusp region shows less than 1% (δIisat/Iisat physics parameter space relevant to both laboratory multi-scale plasmas and astrophysical plasmas.

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

    International Nuclear Information System (INIS)

    Pettier, J.L.; Thierry, R.

    2001-01-01

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

  18. Multi-detector system approach for unattended uranium enrichment monitoring at gas centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Favalli, A.; Lombardi, M.; MacArthur, D. W.; McCluskey, C.; Moss, C. E.

    2017-01-01

    Improving the quality of safeguards measurements at Gas Centrifuge Enrichment Plants while reducing the inspection effort is an important objective given the number of existing and new plants that need to be safeguarded. A useful tool in many safeguards approaches is the on-line monitoring of enrichment in process pipes. One requirement of such a monitor is a simple, reliable and precise passive measurement of the 186-keV line from 235 U. The other information required is the amount of gas in the pipe, which can be obtained by a transmission or pressure measurement. Here, we describe our research to develop such a passive measurement system. Unfortunately, a complication arises in the interpretation of the gamma measurements, from the contribution of uranium deposits on the wall of the pipe to the 186-keV peak. A multi-detector approach to address this complication is presented where two measurements, one with signal primarily from gas and one with signal primarily from deposits, are performed simultaneously with different detectors and geometries. This allows a correction to be made to the 186-keV peak for the contribution from the deposit. Finally, we present the design of the multi-detector system and the results of the experimental calibration of the proof-of-principle prototype built at LANL.

  19. Multi-detector system approach for unattended uranium enrichment monitoring at gas centrifuge enrichment plants

    Science.gov (United States)

    Favalli, A.; Lombardi, M.; MacArthur, D. W.; McCluskey, C.; Moss, C. E.; Paffett, M. T.; Ianakiev, K. D.

    2018-01-01

    Improving the quality of safeguards measurements at Gas Centrifuge Enrichment Plants while reducing the inspection effort is an important objective given the number of existing and new plants that need to be safeguarded. A useful tool in many safeguards approaches is the on-line monitoring of enrichment in process pipes. One requirement of such a monitor is a simple, reliable and precise passive measurement of the 186-keV line from 235U. The other information required is the amount of gas in the pipe, which can be obtained by a transmission or pressure measurement. We describe our research to develop such a passive measurement system. Unfortunately, a complication arises in the interpretation of the gamma measurements, from the contribution of uranium deposits on the wall of the pipe to the 186-keV peak. A multi-detector approach to address this complication is presented where two measurements, one with signal primarily from gas and one with signal primarily from deposits, are performed simultaneously with different detectors and geometries. This allows a correction to be made to the 186-keV peak for the contribution from the deposit. We present the design of the multi-detector system and the results of the experimental calibration of the proof-of-principle prototype built at LANL.

  20. Gamma-ray solid laser: variety of work nuclei and host matrixes in Mendeleev Table screened with use of system of criteria based on joint GG&RH theory

    Science.gov (United States)

    Karyagin, Stanislav V.

    2001-03-01

    The hosts and nuclei-candidates (mass approximately 46 - 243, transition energy approximately 1 - 200 keV, decay's time 10-7 - 10+2 s) for gamma-laser (GL) realization are represented over Mendeleev Table. The choice of active media (nuclei-candidates, hosts) for GL is based on the joint theory of (gamma) -generation and radiation-heat regime which accounts a big complex of hindrances against GL and thus discards many tentative candidates. Nuclei- candidates are screened at the analyzing of data banks for nuclear transitions. Chosen candidates (approximately 20) could be used due to author's method SPTEN (Soft Prompt Transplantation of Excited Nuclei). The discarded tentative nuclei (approximately 80) with the life-times 10-6 - 10+2 are represented too. All analyzed long-lived (approximately 0.5 - 10+2 s) isomers are turned to be not fit for GL without use of very strong multi-wave Borrman effect even at the supposition of natural line's width. The application of the revealed candidates in two different (gamma) -laser's categories (residential and non- residential) is discussed.

  1. Coaxial Mono-Energetic Gamma Generator for Active Interrogation

    International Nuclear Information System (INIS)

    Ludewigt, Bernhard A.; Antolak, A.J.; Henestroza, E.; Leitner, M.; Leung, K.-N.; Waldron, W.; Wilde, S.; Kwan, J.W.

    2008-01-01

    Compact mono-energetic photon sources are sought for active interrogation systems to detect shielded special nuclear materials in, for example, cargo containers, trucks and other vehicles. A prototype gamma interrogation source has been designed and built that utilizes the 11B(p,gamma)12C reaction to produce 12 MeV gamma-rays which are near the peak of the photofission cross section. In particular, the 11B(p,gamma)12C resonance at 163 kV allows the production of gammas at low proton acceleration voltages, thus keeping the design of a gamma generator comparatively small and simple. A coaxial design has been adopted with a toroidal-shaped plasma chamber surrounding a cylindrical gamma production target. The plasma discharge is driven by a 2 MHz rf-power supply (capable up to 50 kW) using a circular rf-antenna. Permanent magnets embedded in the walls of the plasma chamber generate a multi-cusp field that confines the plasma and allows higher plasma densities and lower gas pressures. About 100 proton beamlets are extracted through a slotted plasma electrode towards the target at the center of the device that is at a negative 180 kV. The target consists of LaB6 tiles that are brazed to a water-cooled cylindrical structure. The generator is designed to operate at 500 Hz with 20 mu s long pulses, and a 1percent duty factor by pulsing the ion source rf-power. A first-generation coaxial gamma source has been built for low duty factor experiments and testing.

  2. Detection of gamma rays using scintillation optical fibers

    International Nuclear Information System (INIS)

    Park, J. W.; Hong, S. B.

    2002-01-01

    Scintillating optical fibers have several advantages over other conventional materials used for radiation detection. We have used glass and plastic scintillating fibers to detect gamma rays emitted from 60 Co and 137 Cs, and beta rays from 90 Sr. The sensors are constructed of single strand or multi-strand fibers of 1 mm diameter. The glass scintillating fiber used contains cerium-activated lithium-silicate as scintillating material and the plastic scintillating fiber used is Bicron model BCF-12. In this paper, we report the pulse-height spectra obtained by both sensor types, and analyze them in the aspect of their usability for radiation detectors. Our investigation suggests that the glass fiber can be used to develop gamma ray detectors which will function in high and low gamma ray flux environments. Use of the sensor for the beta ray detection was not satisfactory. The plastic fiber sensor did not work satisfactorily for the weak gamma sources, but did produce somewhat promising results. The scintillating plastic fiber offers some feasibility as beta ray sensor material

  3. Models of Emission-Line Profiles and Spectral Energy Distributions to Characterize the Multi-Frequency Properties of Active Galactic Nuclei

    Directory of Open Access Journals (Sweden)

    Giovanni La Mura

    2017-11-01

    Full Text Available The spectra of active galactic nuclei (AGNs are often characterized by a wealth of emission lines with different profiles and intensity ratios that lead to a complicated classification. Their electromagnetic radiation spans more than 10 orders of magnitude in frequency. In spite of the differences between various classes, the origin of their activity is attributed to a combination of emitting components, surrounding an accreting supermassive black hole (SMBH, in the unified model. Currently, the execution of sky surveys, with instruments operating at various frequencies, provides the possibility to detect and to investigate the properties of AGNs on very large statistical samples. As a result of the spectroscopic surveys that allow the investigation of many objects, we have the opportunity to place new constraints on the nature and evolution of AGNs. In this contribution, we present the results obtained by working on multi-frequency data, and we discuss their relations with the available optical spectra. We compare our findings with the AGN unified model predictions, and we present a revised technique to select AGNs of different types from other line-emitting objects. We discuss the multi-frequency properties in terms of the innermost structures of the sources.

  4. Multi-Frequency Observations of Gamma-Ray Blazar 1633+382 SG ...

    Indian Academy of Sciences (India)

    Gamma-rays—quasars: 1633+382(4C+38.41)—radio jets— polarization. 1. Introduction. Blazars are the most numerous objects in the γ-ray sky (Abdo et al. 2010). They show dramatic variability across the electromagnetic spectrum (e.g., Jorstad et al. 2010; Marscher et al. 2010). Both these properties (strong γ-ray emission.

  5. Evaluation of a gamma-spectroscopy gauge for uranium-plutonium assay

    International Nuclear Information System (INIS)

    Notea, A.; Segal, Y.

    1976-01-01

    A procedure is presented for the characterization of a gamma passive method for non-destructive analysis of nuclear fuel. The approachh provides an organized and systematic way for optimizing the assay system. The key function is the relative resolving power defined as the smallest relative change in the quantity of radionuclide measured that may be detected within a certain confidence level. This function is derived for nuclear fuel employing a model based on empirical parameters. The ability to detect changes in fuels of binary and trinary compositions with a 50-cm 3 Ge(Li) at a 1-min counting period is discussed. As an example to a binary composition, an enriched uranium fuel was considered. The 185-keV and 1001-keV gamma lines are used for the assay of 235 U and 238 U, respectively. As a trinary composition a plutonium-containing fuel was examined. The plutonium was identified by the 414-keV gamma line. The interference of the high-energy lines is carefully analysed, and numerical results are presented. For both cases the range of measurement under specific accuracy demands is determined. The approac described is suitable also for evaluation of other passive as well as active assay methods. (author)

  6. A high rate gamma spectroscopy system for activation analysis of short lived isomeric transitions

    Energy Technology Data Exchange (ETDEWEB)

    Westphal, G P [Atominstitut, Vienna (Austria)

    1976-07-01

    A high rate spectroscopy system specially suited for measurement of short-lived isomeric transitions is described, which, as part of a fast activation analysis facility at the TRIGA Mark II reactor, provides for automatic recording and immediate evaluation of gamma spectra taken from nuclides activated at stationary or pulsed reactor power. The system consists of a commercial DC-coupled Ge(Li)-detector of 70 cm{sup 3} modified for recycling operation for input rates in excess of 500,000 c/s Co-60, a time variant trapezoidal shaping section and a fast constant dead-time ADC coupled to a programmed multi-channel analyzer. Novel circuits for efficient pile-up rejection and time variant base line restoration extend the concept of gated integration up to count rates of more than 300,000 c/s Co-60. Time-sequenced recording of spectra is performed by a mini computer operated as a front-end processor of a larger laboratory computer, where final data processing takes place. New concepts for very simple and cost-effective implementation of multi-channel analyzers by means of general purpose small computers are described. (author)

  7. Optical telescope BIRT in ORIGIN for gamma ray burst observing

    DEFF Research Database (Denmark)

    Content, Robert; Content, Robert; Sharples, Ray

    2012-01-01

    The ORIGIN concept is a space mission with a gamma ray, an X-ray and an optical telescope to observe the gamma ray bursts at large Z to determine the composition and density of the intergalactic matter in the line of sight. It was an answer to the ESA M3 call for proposal. The optical telescope i...... length. All 3 instruments use the same 2k x 2k detector simultaneously so that telescope pointing and tip-tilt control of a fold mirror permit to place the gamma ray burst on the desired instrument without any other mechanism. © 2012 SPIE....

  8. PC-AT to gamma camera interface ANUGAMI-S

    International Nuclear Information System (INIS)

    Bhattacharya, Sadhana; Gopalakrishnan, K.R.

    1997-01-01

    PC-AT to gamma camera interface is an image acquisition system used in nuclear medicine centres and hospitals. The interface hardware and acquisition software have been designed and developed to meet most of the routine clinical applications using gamma camera. The state of the art design of the interface provides quality improvement in addition to image acquisition, by applying on-line uniformity correction which is very essential for gamma camera applications in nuclear medicine. The improvement in the quality of the image has been achieved by image acquisition in positionally varying and sliding energy window. It supports all acquisition modes viz. static, dynamic and gated acquisition modes with and without uniformity correction. The user interface provides the acquisition in various user selectable frame sizes, orientation and colour palettes. A complete emulation of camera console has been provided along with persistence scope and acquisition parameter display. It is a universal system which provides a modern, cost effective and easily maintainable solution for interfacing any gamma camera to PC or upgradation of analog gamma camera. (author). 4 refs., 3 figs

  9. GRB 081029: A Gamma-Ray Burst with a Multi-Component Afterglow

    Science.gov (United States)

    Holland, Stephen T.; De Pasquale, Massimiliano; Mao, Jirong; Sakamoto, Takanori; Schady, Patricia; Covino, Stefano; Fan, Yi-Zhong; Jin, Zhi-Ping; D'Avanzo, Paolo; Antonelli, Angelo; hide

    2012-01-01

    We present an analysis of the unusual optical light curve of the gamma-ray burst GRB 081029, a long-soft burst with a redshift of z = 3.8479. We combine X-ray and optical observations from the Swift X-Ray Telescope and the Swift Ultra Violet/Optical Telescope with ground-based optical and infrared data obtained using the REM, ROTSE, and CTIO 1.3-m telescopes to construct a detailed data set extending from 86 s to approx.100,000 s after the BAT trigger. Our data covers a wide energy range, from 10 keV to 0.77 eV (1.24 A to 16000 A). The X-ray afterglow shows a shallow initial decay followed by a rapid decay starting at about 18,000 s. The optical and infrared afterglow, however, shows an uncharacteristic rise at about 3000 s that does not correspond to any feature in the X-ray light curve. Our data are not consistent with synchrotron radiation from a jet interacting with an external medium, a two-component jet, or continuous energy injection from the central engine. We find that the optical light curves can be broadly explained by a collision between two ejecta shells within a two-component jet. A growing number of gamma-ray burst afterglows are consistent with complex jets, which suggests that some (or all) gamma-ray burst jets are complex and will require detailed modelling to fully understand them.injection

  10. GRB 081029: A Gamma-Ray Burst with a Multi-Component Afterglow

    Science.gov (United States)

    Holland, Stephen T.; DePasquale, Massimiliano; Mao, Jirong; Sakamoto, Taka; Shady, Patricia; Covino, Stefano; Yi-Zhong, Fan; Zhi-Ping, Jin; D'Avanzo, Paolo; Antonelli, Angelo; hide

    2011-01-01

    We present an analysis of the unusual optical light curve of the gamma-ray burst GRB 081029, a long-soft burst with a redshift of z = 3.8479. We combine X-ray and optical observations from the Swift X-Ray Telescope and the Swift UltraViolet Optical Telescope with ground-based optical and infrared data obtained using the REM and ROTSE telescopes to construct a detailed data set extending from 86 s to approx. 100000 s after the BAT trigger. Our data cover a wide energy range, from 10 keV to 0.77 eV (1.24 A to 16000 A). The X-ray afterglow shows a shallow initial decay followed by a rapid decay starting at about 18000 s. The optical and infrared afterglow, however, shows an uncharacteristic rise at about 5000 s that does not correspond to any feature in the X-ray light curve. Our data are not consistent with synchrotron radiation from a jet interacting with an external medium, a two-component jet, or continuous energy injection from the central engine. We find that the the optical light curves can be broadly explained by a collision between two ejecta shells within a two-component jet. A growing number of gamma-ray burst afterglows are consistent with complex jets, which suggests that some (or all) gamma-ray burst jets are complex and will require detailed modelling to fully understand them.

  11. GRB 081029: A GAMMA-RAY BURST WITH A MULTI-COMPONENT AFTERGLOW

    Energy Technology Data Exchange (ETDEWEB)

    Holland, Stephen T.; Sakamoto, Takanori [Astrophysics Science Division, Code 660.1, 8800 Greenbelt Road, Goddard Space Flight Centre, Greenbelt, MD 20771 (United States); De Pasquale, Massimiliano; Schady, Patricia [Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking RH5 6NT (United Kingdom); Mao, Jirong; Covino, Stefano; Jin, Zhi-Ping; D' Avanzo, Paolo; Chincarini, Guido [INAF-Osservatorio Astronomico di Brera, Via Emilio Bianchi 46, I-23807 Merate (Saint Lucia) (Italy); Fan, Yi-Zhong [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China); Antonelli, Angelo; D' Elia, Valerio; Fiore, Fabrizio [INAF-Osservatorio Astronomico di Roma, Via de Frascati 33, I-00040 Monteporzio Catone (Roma) (Italy); Pandey, Shashi Bhushan [Randall Laboratory of Physics, University of Michigan, 450 Church St, Ann Arbor, MI 48109-1040 (United States); Cobb, Bethany E., E-mail: Stephen.T.Holland@nasa.gov [Department of Physics, The George Washington University, 725 21st St NW, Washington, DC 20052 (United States)

    2012-01-20

    We present an analysis of the unusual optical light curve of the gamma-ray burst GRB 081029, a long-soft burst with a redshift of z = 3.8479. We combine X-ray and optical observations from the Swift X-Ray Telescope and the Swift UltraViolet/Optical Telescope with ground-based optical and infrared data obtained using the REM, ROTSE, and CTIO 1.3 m telescopes to construct a detailed data set extending from 86 s to {approx}100000 s after the BAT trigger. Our data cover a wide energy range from 10 keV to 0.77 eV (1.24 A-16000 A). The X-ray afterglow shows a shallow initial decay followed by a rapid decay starting at about 18000 s. The optical and infrared afterglow, however, shows an uncharacteristic rise at about 3000 s that does not correspond to any feature in the X-ray light curve. Our data are not consistent with synchrotron radiation from a jet interacting with an external medium, a two-component jet, or continuous energy injection from the central engine. We find that the optical light curves can be broadly explained by a collision between two ejecta shells within a two-component jet. A growing number of gamma-ray-burst afterglows are consistent with complex jets, which suggests that some (or all) gamma-ray-burst jets are complex and will require detailed modeling to fully understand them.

  12. Numerical study on determining formation porosity using a boron capture gamma ray technique and MCNP.

    Science.gov (United States)

    Liu, Juntao; Zhang, Feng; Wang, Xinguang; Han, Fei; Yuan, Zhelong

    2014-12-01

    Formation porosity can be determined using the boron capture gamma ray counting ratio with a near to far detector in a pulsed neutron-gamma element logging tool. The thermal neutron distribution, boron capture gamma spectroscopy and porosity response for formations with different water salinity and wellbore diameter characteristics were simulated using the Monte Carlo method. We found that a boron lining improves the signal-to-noise ratio and that the boron capture gamma ray counting ratio has a higher sensitivity for determining porosity than total capture gamma. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Optimal multicasting in a multi-line-rate ethernet-over-WDM network

    Science.gov (United States)

    Harve, Shruthi; Batayneh, Marwan; Mukherjee, Biswanath

    2009-11-01

    Ethernet is the dominant transport technology for Local Area Networks. Efforts are now under way to use carrier-grade Ethernet in backbone networks of different service providers. With the advent of applications such as IPTV and Videoon- Demand, there is need for techniques to route multicast traffic over the Ethernet backbone networks. Here, we address the problem of Routing and Wavelength Assignment (RWA) of a set of multicast requests in a Multi-Line-Rate Ethernet backbone network with the objective of minimizing the cost of setting up the network, in terms of the Service Provider's Capital Expenditure (CAPEX). We present an Auxiliary Graph based heuristic algorithm that routes each multicast request on a light-tree structure, and assigns minimum cost wavelengths along the route. We compare the properties of the algorithm to the optimal solution given by a mathematical model formulated as an Integer Linear Program (ILP), and show that they compare very well. We also find that the algorithm is most cost-effective when the incoming requests are processed in descending order of their bandwidth requirements.

  14. On-line dynamic monitoring automotive exhausts: using BP-ANN for distinguishing multi-components

    Science.gov (United States)

    Zhao, Yudi; Wei, Ruyi; Liu, Xuebin

    2017-10-01

    Remote sensing-Fourier Transform infrared spectroscopy (RS-FTIR) is one of the most important technologies in atmospheric pollutant monitoring. It is very appropriate for on-line dynamic remote sensing monitoring of air pollutants, especially for the automotive exhausts. However, their absorption spectra are often seriously overlapped in the atmospheric infrared window bands, i.e. MWIR (3 5μm). Artificial Neural Network (ANN) is an algorithm based on the theory of the biological neural network, which simplifies the partial differential equation with complex construction. For its preferable performance in nonlinear mapping and fitting, in this paper we utilize Back Propagation-Artificial Neural Network (BP-ANN) to quantitatively analyze the concentrations of four typical industrial automotive exhausts, including CO, NO, NO2 and SO2. We extracted the original data of these automotive exhausts from the HITRAN database, most of which virtually overlapped, and established a mixed multi-component simulation environment. Based on Beer-Lambert Law, concentrations can be retrieved from the absorbance of spectra. Parameters including learning rate, momentum factor, the number of hidden nodes and iterations were obtained when the BP network was trained with 80 groups of input data. By improving these parameters, the network can be optimized to produce necessarily higher precision for the retrieved concentrations. This BP-ANN method proves to be an effective and promising algorithm on dealing with multi-components analysis of automotive exhausts.

  15. Multi-objective optimization algorithms for mixed model assembly line balancing problem with parallel workstations

    Directory of Open Access Journals (Sweden)

    Masoud Rabbani

    2016-12-01

    Full Text Available This paper deals with mixed model assembly line (MMAL balancing problem of type-I. In MMALs several products are made on an assembly line while the similarity of these products is so high. As a result, it is possible to assemble several types of products simultaneously without any additional setup times. The problem has some particular features such as parallel workstations and precedence constraints in dynamic periods in which each period also effects on its next period. The research intends to reduce the number of workstations and maximize the workload smoothness between workstations. Dynamic periods are used to determine all variables in different periods to achieve efficient solutions. A non-dominated sorting genetic algorithm (NSGA-II and multi-objective particle swarm optimization (MOPSO are used to solve the problem. The proposed model is validated with GAMS software for small size problem and the performance of the foregoing algorithms is compared with each other based on some comparison metrics. The NSGA-II outperforms MOPSO with respect to some comparison metrics used in this paper, but in other metrics MOPSO is better than NSGA-II. Finally, conclusion and future research is provided.

  16. The influence of increasing dietary fat or protein on the efficiency of broiler chickens exposed to low levels of gamma-rays

    International Nuclear Information System (INIS)

    Ezzat, I.E.; Ghazalah, A.A.

    2002-01-01

    A total of 400 one-day-old chicks, from hubbard line of meat production type, were used in this study. The chicks were divided into three nutritional groups. The second group was fed on a high protein feed containing 3% protein higher than that of the normal diet (group one). The fat level was increased by 4% in the feed of the third group over the value of the normal diet. Each group was divided again into four subgroup treatments (To, T1, T2, and T3) according to the exposure to gamma rays in a single or multi doses. The aim of this study was to compare between the nutritional types and its combinations with the applied doses of gamma rays on broiler performance. The results can be summarized as follows: The broiler chicks fed on the high fat ration and exposed to 0.25 Gy of gamma-rays four times (group 111, T3) recorded the highest body weight gain along the duration of the experiment. in general, the stimulation effect of the gamma-ray doses applied herein was obvious during the period of rapid growth (0-4 weeks of age) then it was followed by retardation in growth rate. The group of chicks fed on a diet containing high fat (group 111), achieved the crude fiber and nitrogen extract digestibility's. Increase of dietary protein was accompanied by a significant increase in carcass protein, water and ash content. Carcass fat was increased while carcass water was decreased with low level of gamma rays

  17. TEV GAMMA-RAY OBSERVATIONS OF THE GALACTIC CENTER RIDGE BY VERITAS

    Energy Technology Data Exchange (ETDEWEB)

    Archer, A.; Buckley, J. H.; Bugaev, V. [Department of Physics, Washington University, St. Louis, MO 63130 (United States); Benbow, W.; Cerruti, M. [Fred Lawrence Whipple Observatory, Harvard-Smithsonian Center for Astrophysics, Amado, AZ 85645 (United States); Bird, R.; Collins-Hughes, E. [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Buchovecky, M. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States); Byrum, K. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States); Cardenzana, J. V; Eisch, J. D. [Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States); Chen, X. [Institute of Physics and Astronomy, University of Potsdam, D-14476 Potsdam-Golm (Germany); Ciupik, L. [Astronomy Department, Adler Planetarium and Astronomy Museum, Chicago, IL 60605 (United States); Connolly, M. P. [School of Physics, National University of Ireland Galway, University Road, Galway (Ireland); Falcone, A. [Department of Astronomy and Astrophysics, 525 Davey Lab, Pennsylvania State University, University Park, PA 16802 (United States); Feng, Q.; Finley, J. P. [Department of Physics and Astronomy, Purdue University, West Lafayette, IN 47907 (United States); Fleischhack, H. [DESY, Platanenallee 6, D-15738 Zeuthen (Germany); Flinders, A. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Fortson, L., E-mail: asmith44@umd.edu [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); and others

    2016-04-20

    The Galactic Center ridge has been observed extensively in the past by both GeV and TeV gamma-ray instruments revealing a wealth of structure, including a diffuse component and the point sources G0.9+0.1 (a composite supernova remnant) and Sgr A* (believed to be associated with the supermassive black hole located at the center of our Galaxy). Previous very high energy (VHE) gamma-ray observations with the H.E.S.S. experiment have also detected an extended TeV gamma-ray component along the Galactic plane in the >300 GeV gamma-ray regime. Here we report on observations of the Galactic Center ridge from 2010 to 2014 by the VERITAS telescope array in the >2 TeV energy range. From these observations we (1) provide improved measurements of the differential energy spectrum for Sgr A* in the >2 TeV gamma-ray regime, (2) provide a detection in the >2 TeV gamma-ray emission from the composite SNR G0.9+0.1 and an improved determination of its multi-TeV gamma-ray energy spectrum, and (3) report on the detection of VER J1746-289, a localized enhancement of >2 TeV gamma-ray emission along the Galactic plane.

  18. Conceptual design of gamma irradiator (ISG-500) for preservation of farming product

    International Nuclear Information System (INIS)

    S Budihardjo; Dian F Atmoko; Syamsurijjal Ramja; Sutomo; A Suntoro; Pudjijanto MS; Nada Mamada

    2010-01-01

    A conceptual design of gamma irradiator ISG-500 for a preservation of farming product has been done. The design of gamma irradiator are multi purpose with the activity of radiation source used at 2x250 kCi cobalt-60. This gamma irradiator will be built by using local materials, like as for the building structure construction, the mechanical and electrical systems and for the instrumentation and control systems. The sources of radiation that will be used is Co60 pencil types (C 188 - Nordion), concrete structured building according to BAPETEN rule and the numbers of carriers that will be used are 15 carriers. (author)

  19. Automatic storage of single gamma spectra on magnetic tape. Programs Longo, Dire

    International Nuclear Information System (INIS)

    Los Arcos Merino, J.M.

    1978-01-01

    The program Longo provides the block size and the black number in a binary file on magnetic tape. It has been applied to analyse the structure of the nine-track magnetic tapes storing single or coincidence gamma spectra files, recorded in octet form by a Multi-8 minicomputer in the Nuclear Spectrometry Laboratory of J.E.N. Then the program Dire has been written to transform the single gamma spectra into a new Fastrand disk file, storing the information in 36 bit words. A copy of this file is obtained on magnetic tape and the single gamma spectra are then availables by standard Fortran V reading sentences. (author)

  20. Automatic storing of single gamma spectra on magnetic tape. Programs LONGO, DIRE

    International Nuclear Information System (INIS)

    Los Arcos Merino, J. M.

    1978-01-01

    The program LONGO provides the block size and the block number in a binary file on magnetic tape. It has been applied to analyse the structure of the nine-track magnetic tapes storing single or coincidence gamma spectra files, recorded in octet form by a MULTI-8 minicomputer in the Nuclear Spectrometry Laboratory of J.E.N. Then the program DIRE has been written to transform the single gamma spectra into a new FASTRAND disk file, storing the information in-36 bit words. A copy of this file is obtained on magnetic tape and the single gamma spectra are then available by standard FORTRAN V reading sentences. (Author) 3 refs

  1. Modelling plastic scintillator response to gamma rays using light transport incorporated FLUKA code

    Energy Technology Data Exchange (ETDEWEB)

    Ranjbar Kohan, M. [Physics Department, Tafresh University, Tafresh (Iran, Islamic Republic of); Etaati, G.R. [Department of Nuclear Engineering and Physics, Amir Kabir University of Technology, Tehran (Iran, Islamic Republic of); Ghal-Eh, N., E-mail: ghal-eh@du.ac.ir [School of Physics, Damghan University, Damghan (Iran, Islamic Republic of); Safari, M.J. [Department of Energy Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Afarideh, H. [Department of Nuclear Engineering and Physics, Amir Kabir University of Technology, Tehran (Iran, Islamic Republic of); Asadi, E. [Department of Physics, Payam-e-Noor University, Tehran (Iran, Islamic Republic of)

    2012-05-15

    The response function of NE102 plastic scintillator to gamma rays has been simulated using a joint FLUKA+PHOTRACK Monte Carlo code. The multi-purpose particle transport code, FLUKA, has been responsible for gamma transport whilst the light transport code, PHOTRACK, has simulated the transport of scintillation photons through scintillator and lightguide. The simulation results of plastic scintillator with/without light guides of different surface coverings have been successfully verified with experiments. - Highlights: Black-Right-Pointing-Pointer A multi-purpose code (FLUKA) and a light transport code (PHOTRACK) have been linked. Black-Right-Pointing-Pointer The hybrid code has been used to generate the response function of an NE102 scintillator. Black-Right-Pointing-Pointer The simulated response functions exhibit a good agreement with experimental data.

  2. Improvement and validation of isotopic libraries of commercial gamma spectra evaluation packages. Report on task FIN A 955 of Finnish support programme to IAEA safeguards

    Energy Technology Data Exchange (ETDEWEB)

    Nikkinen, M.

    1997-06-01

    The Department of Safeguards at the International Atomic Energy Agency (IAEA) is running gamma spectroscopy analysis with various samples taken at various stages of the nuclear fuel cycle. It was found that the commercial gamma spectra analysis packages available do not include proper gamma-line libraries for the various tasks needed for the safeguards purposes because the libraries of these packages are often incomplete and outdated. New libraries were developed to satisfy the needs in the analysis tasks required for the safeguards purposes. These lines are limited by the number of gamma lines to avoid the problems with too many candidates for a single gamma peak. The work was carried out under the Task FIN A 955 Finnish Support Programme to IAEA Safeguards. (orig.) (18 refs.).

  3. Study of the gamma radiation of ionium

    Energy Technology Data Exchange (ETDEWEB)

    Curie, I

    1949-12-01

    A Geiger counter study has been made of the ..gamma.. radiation of ionium. Eleven quanta of the L radiation of radium were observed for every hundred ..cap alpha.. disintegrations, and three ..gamma.. rays were found with energies of 68, 140, and 240 keV at a rate of 0.85, 0.33, 0.05 quanta, respectively, for 100 disintegrations. It is noted that the radiation spectrum of ionium as a whole is difficult to interpret. In the course of this work, the author calculated the efficiency of a thin-walled aluminum counter, both for the L radiation of radium and for ..gamma.. rays of 68 keV. The author also measured, for soft radiation, the ratio between the efficiency of a thin-walled aluminum counter and that of a similar counter lined with 0.11 mm of lead.

  4. In-core program for on line measurements of neutron, photon and nuclear heating parameters inside Jules Horowitz MTR reactor

    International Nuclear Information System (INIS)

    Lyoussi, A.; Reynard-Carette, C.

    2014-01-01

    Accurate on-line measurements of key parameters inside experimental channels of Material Testing Reactor are necessary to dimension the irradiation devices and consequently to conduct smart experiments on fuels and materials under suitable conditions. In particular the quantification of nuclear heating, a relevant parameter to reach adapted thermal conditions, has to be improved. These works focus on an important collaborative program between CEA and Aix-Marseille University called INCORE (Instrumentation for Nuclear radiations and Calorimetry On-line in Reactor) dedicated to the development of a new measurement methodology to quantify both nuclear heating and accurate radiation flux levels (neutrons and photons). The methodology, which is based on experiments carried out under irradiation conditions with a multi-sensor device (ionization chamber, fission chamber, gamma thermometer, calorimeter, SPND, SPGD) as well as works performed out-of nuclear/radiative environment on a reference sensor used to measure nuclear heating (calorimeter), is presented (authors)

  5. New determinations of gamma-ray line intensities of the E{sub p}=550 and 1747 keV resonances of the {sup 13}C(p,{gamma}){sup 14}N reaction

    Energy Technology Data Exchange (ETDEWEB)

    Kiener, J. E-mail: kiener@csnsm.in2p3.fr; Gros, M.; Tatischeff, V.; Attie, D.; Bailly, I.; Bauchet, A.; Chapuis, C.; Cordier, B.; Deloncle, I.; Porquet, M.G.; Schanne, S.; Sereville, N. de; Tauzin, G

    2004-03-01

    Gamma-ray angular distributions for the resonances at E{sub p}=550 and 1747 keV of the radiative capture reaction {sup 13}C(p,{gamma}){sup 14}N have been measured, using intense proton beams on isotopically pure {sup 13}C targets. Experimental gamma-ray spectra were obtained with three HP-Germanium detectors at four angles for E{sub p}=550 keV and six angles for E{sub p}=1747 keV in the range of 0-90 deg. with respect to the proton beam. From the data, relative intensities for the strongest transitions were extracted with an accuracy of typically 5%, making these resonances new useful gamma-ray standards for efficiency calibration in the energy range from E{sub {gamma}}=1.6-9 MeV. Gamma-ray branching ratios were obtained for several levels of {sup 14}N and are compared with literature values.

  6. Energy–angle correlation of neutrons and gamma-rays emitted from an HEU source

    Energy Technology Data Exchange (ETDEWEB)

    Miloshevsky, G., E-mail: gennady@purdue.edu; Hassanein, A.

    2014-06-01

    Special Nuclear Materials (SNM) yield very unique fission signatures, namely correlated neutrons and gamma-rays. A major challenge is not only to detect, but also to rapidly identify and recognize SNM with certainty. Accounting for particle multiplicity and correlations is one of standard ways to detect SNM. However, many parameter data such as joint distributions of energy, angle, lifetime, and multiplicity of neutrons and gamma-rays can lead to better recognition of SNM signatures in the background radiation noise. These joint distributions are not well understood. The Monte Carlo simulations of the transport of neutrons and gamma-rays produced from spontaneous and interrogation-induced fission of SNM are carried out using the developed MONSOL computer code. The energy spectra of neutrons and gamma-rays from a bare Highly Enriched Uranium (HEU) source are investigated. The energy spectrum of gamma-rays shows spectral lines by which HEU isotopes can be identified, while those of neutrons do not show any characteristic lines. The joint probability density function (JPDF) of the energy–angle association of neutrons and gamma-rays is constructed. Marginal probability density functions (MPDFs) of energy and angle are derived from JPDF. A probabilistic model is developed for the analysis of JPDF and MPDFs. This probabilistic model is used to evaluate mean values, standard deviations, covariance and correlation between the energy and angle of neutrons and gamma-rays emitted from the HEU source. For both neutrons and gamma-rays, it is found that the energy–angle variables are only weakly correlated.

  7. $\\gamma$-$\\gamma$ and $\\gamma$-p events at high energies

    CERN Document Server

    Schuler, Gerhard A.; Gerhard A Schuler; Torbjorn Sjostrand

    1994-01-01

    A real photon has a complicated nature, whereby it may remain unresolved or fluctuate into a vector meson or a perturbative q-qbar pair. Based on this picture, we previously presented a model for gamma-p events that is based on the presence of three main event classes: direct, VMD and anomalous. In gamma-gamma events, a natural generalization gives three-by-three combinations of the nature of the two incoming photons, and thus six distinct event classes. The properties of these classes are constrained by the choices already made, in the gamma-p model, of cut-off procedures and other aspects. It is therefore possible to predict the energy-dependence of the cross section for each of the six components separately. The total cross section thus obtained is in good agreement with data, and also gives support to the idea that a simple factorized ansatz with a pomeron and a reggeon term can be a good approximation. Event properties undergo a logical evolution from p-p to gamma-p to gamma-gamma events, with larger cha...

  8. PC-AT to gamma camera interface Anugami-S

    International Nuclear Information System (INIS)

    Bhattacharya, Sadhana; Sonalkar, S.Y.; Kataria, S.K.

    2000-01-01

    The gamma camera interface ANUGAMI-S is an image acquisition system used in nuclear medicine centres and hospitals. The state of the art design of the interface provides quality improvement in addition to image acquisition, by applying on-line uniformity correction which is very essential for gamma camera applications in nuclear medicine. The improvement in the quality of the image has been achieved by image acquisition in positionally varying and sliding energy window. It supports all acquisition modes viz. static, dynamic and gated acquisition modes with and without uniformity correction. The user interface provides the acquisition in various user selectable parameters with image display and related acquisition parameter display. It is a universal system which provides a modern, cost effective and easily maintainable solution for interfacing any gamma camera to PC or upgradation of analog gamma camera. The paper describes the system details and gated acquisition achieved on the present system. (author)

  9. Stress coarsening of gamma-prime and its influence on creep properties of a single crystal superalloy

    International Nuclear Information System (INIS)

    Pearson, D.D.; Lemkey, F.D.; Kear, B.H.

    1980-01-01

    The effect of stress annealing on the gamma-prime morphology in single crystals of a Ni-13Al-9Mo-2Ta alloy is examined. It is found that a crystal subjected to tensile creep in the 100 line orientation develops platelets, or rafts, of gamma-prime in orientations perpendicular to the applied stress. Due to the large negative gamma/gamma-prime misfit (about 0.7%) in this alloy, the gamma/gamma-prime interfaces feature high-density misfit dislocations. Under a stress of 207 MPa at 1038 C, the rafted gamma-prime structure exhibits a rupture life of over 400 hr as compared with 100 hr for unrafted material

  10. Automatic classification of gammas-gamma coincidence matrices; Clasificacion automatizada de matrices de coincidencias Gamma-Gamma

    Energy Technology Data Exchange (ETDEWEB)

    Los Arcos Merino, J M; Gonzalez, J A

    1978-07-01

    The information obtained during a coincidence experiment, recorded on magnetic tape by a MULTI-8 minicomputer, is transferred to a new tape in 36 bit words, using the program LEC0M8. The classification in two dimensional matrix form is carried out off-line, on a magnetic disk file, by the program CLAFI. On finishing classification one obtains a copy of the coincidence matrix on the second magnetic tape. Both programs are written to be processed in that order with the UNIVAC 1106 computer of J.E.N. (Author) 4 refs.

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

    Science.gov (United States)

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

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

  12. Remote planetary geochemical exploration with the NEAR X-ray/gamma-ray spectrometer

    International Nuclear Information System (INIS)

    Trombka, J.I.; Boynton, W.V.; Brueckner, J.; Squyres, S.; Clark, P.E.; Starr, R.; Evans, L.G.; Floyd, S.R.; McClanahan, T.P.; Goldsten, J.; Mcnutt, R.; Schweitzer, J.S.

    1999-01-01

    The X-ray/gamma-ray spectrometer (XGRS) instrument onboard the Near Earth Asteroid Rendezvous (NEAR) spacecraft will map asteroid 433 Eros in the 0.2 keV to 10 MeV energy region. Measurements of the discrete line X-ray and gamma-ray emissions in this energy domain can be used to obtain both qualitative and quantitative elemental composition maps of the asteroid surface. The NEAR X-ray/gamma-ray spectrometer (XGRS) was turned on for the first time during the week of 7 April 1996. Rendezvous with Eros 433 is expected during December 1998. Observations of solar X-ray spectra during both quiescent and active periods have been made. A gamma-ray transient detection system has been implemented and about three gamma-ray transient events a week have been observed which are associated with either gamma-ray bursts or solar flares

  13. Development of multiphase meter using gamma densitometer concept

    International Nuclear Information System (INIS)

    Babelli, I.M.M.

    1997-01-01

    The ability to accurately predict the void fraction of the different phases flowing in a conduit is of extreme importance to the nuclear and oil industries, among others. Some of the major obstacles in performing accurate measurements result directly from the operating conditions of the system involved. The case study in this paper will focus on the issue of predicting the volumetric fraction in oil transport pipelines. Gamma densitometer utilizes the concept of gamma attenuation in matter where the magnitude of attenuation is directly related to the density of the material through which the gamma ray passes, and to the intensity of the ray itself By calibrating the gamma ray with a variety of known flow geometries, one can extrapolate the findings to cover all ranges of flow regimes present in a large horizontal pipe, typical of an oil transport pipeline. The advantage of using gamma densitometers is that it is a non-intrusive technique, relatively inexpensive and portable. Its main disadvantage is that the collimated beam of the gamma ray will produce a line averaged value and local information can not be obtained. Another disadvantage has to do with the necessity to increase the strength of the gamma source with increase in the thickness and/or density of the pipe wall which will require increased radiation protection and reduces portability

  14. SU-E-T-453: Optimization of Dose Gradient for Gamma Knife Radiosurgery.

    Science.gov (United States)

    Sheth, N; Chen, Y; Yang, J

    2012-06-01

    The goals of stereotactic radiosurgery (SRS) are the ablation of target tissue and sparing of critical normal tissue. We develop tools to aid in the selection of collimation and prescription (Rx) isodose line to optimize the dose gradient for single isocenter intracranial stereotactic radiosurgery (SRS) with GammaKnife 4C utilizing the updated physics data in GammaPlan v10.1. Single isocenter intracranial SRS plans were created to treat the center of a solid water anthropomorphism head phantom for each GammaKnife collimator (4 mm, 8 mm, 14 mm, and 18 mm). The dose gradient, defined as the difference of effective radii of spheres equal to half and full Rx volumes, and Rx treatment volume was analyzed for isodoses from 99% to 20% of Rx. The dosimetric data on Rx volume and dose gradient vs. Rx isodose for each collimator was compiled into an easy to read nomogram as well as plotted graphically. The 4, 8, 14, and 18 mm collimators have the sharpest dose gradient at the 64%, 70%, 76%, and 77% Rx isodose lines, respectively. This corresponds to treating 4.77 mm, 8.86 mm, 14.78 mm, and 18.77 mm diameter targets with dose gradients radii of 1.06 mm, 1.63 mm, 2.54 mm, and 3.17 mm, respectively. We analyzed the dosimetric data for the most recent version of GammaPlan treatment planning software to develop tools that when applied clinically will aid in the selection of a collimator and Rx isodose line for optimal dose gradient and target coverage for single isocenter intracranial SRS with GammaKnife 4C. © 2012 American Association of Physicists in Medicine.

  15. Carborne gamma-ray spectrometry. Calibration and applications

    International Nuclear Information System (INIS)

    Aage, H.K.; Korsbech, U.; Bargholz, K.; Hovgaard, J.

    2006-01-01

    Calibration of carborne gamma-ray spectrometry systems for 137 Cs is carried out with a source successively placed at 791 positions within an area of 34 mx62 m. A computer model supplements the measurements. Hereby a sensitivity map for a surface contamination is generated as well as line and area sensitivities. Another model converts surface sensitivity to sensitivity for a deep contamination. Use of the sensitivity map for a non-homogeneous distribution of 137 Cs is demonstrated. Applications of line sensitivities for special tasks are discussed

  16. Development of an airborne gamma radiation system for snow surveys

    Energy Technology Data Exchange (ETDEWEB)

    Fritzsche, A E [EG and G, Inc., Las Vegas, NV (USA)

    1979-01-01

    An airborne gamma-snow survey system requires detailed design to obtain maximum precision and accuracy. The use of NaI(Te) gamma detectors with a full gamma energy spectrum pulse height analyzer together with a small computer provide a self-contained and flexible system. The dual detector method determines atmospheric radon perturbations in the detection system. Detailed calibration experiments must be performed to determine twenty parameters that describe the physical nature of the system. Multiple high altitude and lake flights are used to obtain background components. Simulation pads, loaded with varying concentrations of /sup 40/K, /sup 232/Th and /sup 23/..gamma..U yield photopeak stripping coefficients and basic system sensitivity. Multiple altitude flights over land lines provide air attenuation coefficients which may converted to water attenuation coefficients.

  17. Contribution to data acquisition software of Eurogram and Diamant multi detectors in an Unix/VXWorks environment

    International Nuclear Information System (INIS)

    Diarra, C.

    1994-06-01

    Questions on nuclear matter, need to have new performant equipments. Eurogram is a 4 PI gamma radiations multi detector and a precious tool in gamma spectroscopy, but it is necessary to use a charged particles detector and in this aim Diamant is an Eurogram partner. These two multi detectors needed special software data acquisition systems. The whole of acquisition control and management is based on sun stations with unix system. 56 figs., 64 refs

  18. Probing the very-high-energy gamma-ray spectral curvature in the blazar PG 1553+113 with the MAGIC telescopes

    CERN Document Server

    Aleksić, J.; Antonelli, L A; Antoranz, P; Babic, A; Bangale, P; Barrio, J A; González, J Becerra; Bednarek, W; Bernardini, E; Biasuzzi, B; Biland, A; Blanch, O; Bonnefoy, S; Bonnoli, G; Borracci, F; Bretz, T; Carmona, E; Carosi, A; Colin, P; Colombo, E; Contreras, J.L; Cortina, J; Covino, S; Da Vela, P; Dazzi, F; De Angelis, A; De Caneva, G; De Lotto, B; Wilhelmi, E de Oña; Mendez, C Delgado; Prester, D Dominis; Dorner, D; Doro, M; Einecke, S; Eisenacher, D; Elsaesser, D; Fidalgo, D; Fonseca, M.V; Font, L; Frantzen, K; Fruck, C; Galindo, D; López, R J García; Garczarczyk, M; Terrats, D Garrido; Gaug, M; Godinović, N; Muñoz, A González; Gozzini, S R; Hadasch, D; Hanabata, Y; Hayashida, M; Herrera, J; Hose, J; Hrupec, D; Idec, W; Kadenius, V; Kellermann, H; Knoetig, M L; Kodani, K; Konno, Y; Krause, J; Kubo, H; Kushida, J; La Barbera, A; Lelas, D; Lewandowska, N; Lindfors, E; Lombardi, S; Longo, F; López, M; López-Coto, R; López-Oramas, A; Lorenz, E; Lozano, I; Makariev, M; Mallot, K; Maneva, G; Mannheim, K; Maraschi, L; Marcote, B; Mariotti, M; Martínez, M; Mazin, D; Menzel, U; Miranda, J M; Mirzoyan, R; Moralejo, A; Munar-Adrover, P; Nakajima, D; Neustroev, V; Niedzwiecki, A; Nilsson, K; Nishijima, K; Noda, K; Orito, R; Overkemping, A; Paiano, S; Palatiello, M; Paneque, D; Paoletti, R; Paredes, J M; Paredes-Fortuny, X; Persic, M; Poutanen, J; Moroni, P G Prada; Prandini, E; Puljak, I; Reinthal, R; Rhode, W; Ribó, M; Rico, J; Garcia, J Rodriguez; Rügamer, S; Saito, T; Saito, K; Satalecka, K; Scalzotto, V; Scapin, V; Schultz, C; Schweizer, T; Sillanpää, A; Sitarek, J; Snidaric, I; Sobczynska, D; Spanier, F; Stamerra, A; Steinbring, T; Storz, J; Strzys, M; Takalo, L; Takami, H; Tavecchio, F; Temnikov, P; Terzić, T; Tescaro, D; Teshima, M; Thaele, J; Tibolla, O; Torres, D F; Toyama, T; Treves, A; Vogler, P; Will, M; Zanin, R; D'Ammando, F; Lähteenmäki, A; Tornikoski, M; Hovatta, T; Readhead, A C S; Max-Moerbeck, W; Richards, J.L

    2015-01-01

    PG 1553+113 is a very-high-energy (VHE, E>100 GeV) gamma-ray emitter classified as a BL Lac object. Its redshift is constrained by intergalactic absorption lines in the range 0.40.2). The observed curvature is compatible with the extragalactic background light (EBL) imprint predicted by the current generation of EBL models assuming a redshift z~0.4. New constraints on the redshift were derived from the VHE spectrum. These constraints are compatible with previous limits and suggest that the source is most likely located around the optical lower limit, z=0.4. Finally, we find that the synchrotron self-Compton (SSC) model gives a satisfactory description of the observed multi-wavelength spectral energy distribution during the flare.

  19. Absolute peak detection efficiencies of a Ge(Li) detector for high gamma-ray energies

    International Nuclear Information System (INIS)

    Katagiri, Masaki

    1985-11-01

    Absolute peak detection efficiencies of a Ge(Li) detector for gamma-rays of 3.5 MeV to 12 MeV were measured using four (p,γ) reactions and a (n,γ) reaction. Two-line-method was used to obtaine peak detection efficiencies. The efficiencies with the both cases are agreed very well. Utilization of (n,γ) reaction is, therefore, effective for measuring these efficiencies, because high energy gamma-rays can be generated easily by using a neutron source. These results were applied to calibration of a gamma-ray standard source, emitting 6.13 MeV gamma-rays, and of intensities of 56 Co standard gamma-ray source. (author)

  20. Cytotoxic activities of amentoflavone against human breast and cervical cancers are mediated by increasing of PTEN expression levels due to peroxisomes proliferate-activated receptor {gamma} activation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eunjung; Shin, Soyoung; Lee, Jeeyoung; Lee, So Jung; Kim, Jinkyoung; Yoon, Doyoung; Kim, Yangmee [Konkuk Univ., Seoul (Korea, Republic of); Woo, Eunrhan [Chosun Univ., Gwangju (Korea, Republic of)

    2012-07-15

    Human peroxisomes proliferate-activated receptor gamma (hPPAR{gamma}) has been implicated in numerous pathologies, including obesity, diabetes, and cancer. Previously, we verified that amentoflavone is an activator of hPPAR{gamma} and probed the molecular basis of its action. In this study, we investigated the mechanism of action of amentoflavone in cancer cells and demonstrated that amentoflavone showed strong cytotoxicity against MCF-7 and HeLa cancer cell lines. We showed that hPPAR{gamma} expression in MCF-7 and HeLa cells is specifically stimulated by amentoflavone, and suggested that amentoflavone-induced cytotoxic activities are mediated by activation of hPPAR{gamma} in these two cancer cell lines. Moreover, amentoflavone increased PTEN levels in these two cancer cell lines, indicating that the cytotoxic activities of amentoflavone are mediated by increasing of PTEN expression levels due to hPPAR{gamma} activation.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-12-15

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

  2. Gamma scanning of full scale HTR fuel elements

    International Nuclear Information System (INIS)

    Harrison, T.A.; Simpson, J.A.H.; Nabielek, H.

    1983-04-01

    Gamma scanning for the determination of burn-up and fission product inventory has been developed at the Dragon Project, suitable for measurements on fuel elements and segments from full-sized integral block elements. This involved the design and construction of a new lead flask with sophisticated collimator design. State-of-the art gamma spectrometric equipment was set up to cope with strong variations of count-rate and high data throughput. Software efforts concentrated on the calculation of the self absorption and absorption corrections in the complicated geometry of multi-hole graphite block segments with a corrugated circumference. The techniques described here are applicable to the non-destructive examination of a wide range of fuel element designs. (author)

  3. An evaluation of measurement uncertainties in the on-line measurement of coal ash content by gamma-ray transmission

    International Nuclear Information System (INIS)

    Wenzhong, Liu; Li, Kong; Tan, Qu; Jingjing, Cheng

    2002-01-01

    In this paper, a significant effect producing systematic errors in the on-line measurement using gamma-ray transmission is revealed. Ash content fluctuations or thickness changes lead to a permanent negative systematic error in the results of the measurements. To study uncertainties in the measurements applicable to time-independent ash content indicators and to investigate the characteristics of the radiation attenuation process, the behavior of the quantity in question is modeled with a stationary Gaussian distribution. A systematic error-producing effect has been found, and a quantitative correction is given to compensate for it. For some other quantities in question that vary in time, a linear model is used to discuss the systematic errors in the case of automated coal gangue separator. Results of experiments that demonstrate different systematic errors for different sampling intervals are presented. The reason for these errors is the nonlinearity of the relationship between the radiation intensity, on the one hand, and the sample thickness and mass attention, on the other

  4. Optics measurements and transfer line matching for the SPS injection of the CERN Multi-Turn Extraction beam

    CERN Document Server

    Benedetto, E; Cettour Cave, S; Follin, F; Gilardoni, S; Giovannozzi, M; Roncarolo, F

    2010-01-01

    Dispersion and beam optics measurements were carried out in the transfer line between the CERN PS and SPS for the new Multi-Turn Extraction beam. Since the extraction conditions of the four islands and the core are different and strongly dependent on the non-linear effects used to split the beam in the transverse plane, a special care was taken during the measurement campaigns. Furthermore, an appropriate strategy was devised to minimize the overall optical mismatch at SPS injection. All this led to a new optical configuration that will be presented in the paper.

  5. Study, simulation and modelling of a gamma photon detector placed on an integral-type eccentric orbit

    International Nuclear Information System (INIS)

    Diallo, N.

    1999-01-01

    Gamma-ray lines are the signature of nuclear reactions and other high-energy processes that take place in the Universe. Their measurement and study provide invaluable information on many important problems in high energy astrophysics, including particle acceleration, physics of compact objects and nucleosynthesis. However the observation of astronomical gamma-ray sources has to be performed above the atmosphere because the Earth's atmosphere is opaque to gamma-rays. Unfortunately at these altitudes, spatial high energy electromagnetic radiation (X and gamma rays) detectors are exposed to intense parasite fluxes of radiation and particles induced by primary galactic cosmic rays. These fluxes as well radiation and secondary particles they generate, constitute a considerable source of background which limits their performances. Our study has been done in the framework of the INTEGRAL mission, a gamma-ray astronomy mission of the European Space Agency. INTEGRAL is devoted to the observation of celestial gamma-ray sources. It consists of two main instruments: an imager IBIS and a high resolution germanium spectrometer SPI (ΔE/E = 1.6 10 -3 at 1.3 MeV). We studied the hadronic component of the SPI background. This component is due to the radioactive decay of unstable nuclides produced by the interactions of cosmic-ray protons with the materials of SPI. It consists of a continuum with gamma ray lines superimposed. To study nuclear processes, Monte Carlo simulations have been performed with the nuclear code TIERCE developed at CEA/DAM. We used the GEANT Monte Carlo code developed at CERN to simulate the germanium detectors response. Background reduction techniques as PSD (Pulse Shape Discrimination) and energetic signatures have been applied in well chosen energy ranges to reduce the background. and improve the SPI sensitivity. With the estimated SPI narrow-line sensitivity level, SPI would be able to detect many gamma ray limes emitted in the active galactic sites

  6. Application of the image calorimeter in the high energy gamma astronomy

    Energy Technology Data Exchange (ETDEWEB)

    Casolino, M.; Sparvoli, R.; Morselli, A.; Picozza, P. [Rome Univ. `Tor Vergata` (Italy). Dip. di Fisica]|[INFN, Sezione Univ. `Tor Vergata`, Rome (Italy); Carlson, P. [Royal Institute of Technology, Stockholm (Sweden); 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

    The capability of registration of the primary high energy cosmic ray gamma emission by a gamma-telescope made of an image calorimeter is shown in this paper. The problem of triggering and off-line identification of primary particles by the analysis of the electromagnetic showers induced in the calorimeter is under consideration. The estimations of the background flux of delayed secondaries induced by nuclear interactions are presented too.

  7. IDENTIFICATION OF NEW GAMMA-RAY BLAZAR CANDIDATES WITH MULTIFREQUENCY ARCHIVAL OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Cowperthwaite, Philip S. [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States); Massaro, F. [SLAC National Laboratory and Kavli Institute for Particle Astrophysics and Cosmology, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); D' Abrusco, R.; Paggi, A.; Smith, Howard A. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Tosti, G., E-mail: pcowpert@umd.edu [Dipartimento di Fisica, Università Degli Studi di Perugia, I-06123 Perugia (Italy)

    2013-11-01

    Blazars are a highly variable, radio-loud subclass of active galactic nuclei. In order to better understand such objects we must be able to easily identify candidate blazars from the growing population of unidentified sources. Working toward this goal, we attempt to identify new gamma-ray blazar candidates from a sample of 102 previously unidentified sources. These sources are selected from The Astronomer's Telegram and the literature on the basis of non-periodic variability and multi-wavelength behavior. We then attempt to associate these objects to an IR counterpart in the Wide-field Infrared Survey Explorer all-sky survey. We are able to identify 16 candidate sources whose IR colors are consistent with those of the blazar population. Of those, 13 sources have IR colors indicative of being gamma-ray emitting blazar candidates. These sources all possess archival multi-wavelength observations that support their blazar-like nature.

  8. Short-term radio variability and parsec-scale structure in A gamma-ray narrow-line Seyfert 1 galaxy 1H 0323+342

    Energy Technology Data Exchange (ETDEWEB)

    Wajima, Kiyoaki [Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Xuhui District, Shanghai 200030 (China); Fujisawa, Kenta [The Research Institute for Time Studies, Yamaguchi University, 1677-1 Yoshida, Yamaguchi, Yamaguchi 753-8511 (Japan); Hayashida, Masaaki [Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8582 (Japan); Isobe, Naoki [The Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa 252-5210 (Japan); Ishida, Takafumi [Graduate School of Science and Engineering, Yamaguchi University, 1677-1 Yoshida, Yamaguchi, Yamaguchi 753-8512 (Japan); Yonekura, Yoshinori, E-mail: kwajima@shao.ac.cn [Center for Astronomy, Ibaraki University, 2-1-1 Bunkyo, Mito, Ibaraki 310-8512 (Japan)

    2014-02-01

    We made simultaneous single-dish and very long baseline interferometer (VLBI) observations of a narrow-line Seyfert 1 galaxy 1H 323+342, showing gamma-ray activity revealed by Fermi/Large Area Telescope observations. We found significant variation of the total flux density at 8 GHz on the timescale of one month by the single-dish monitoring. The total flux density varied by 5.5% in 32 days, which is comparable to the gamma-ray variability timescale, corresponding to the variability brightness temperature of 7.0 × 10{sup 11} K. The source consists of central and southeastern components on the parsec (pc) scale. Only the flux of the central component decreased in the same way as the total flux density, indicating that the short-term radio variability, and probably the gamma-ray-emitting region, is associated with this component. From the VLBI observations, we obtained brightness temperatures of greater than (5.2 ± 0.3) × 10{sup 10} K and derived an equipartition Doppler factor of greater than 1.7, a variability Doppler factor of 2.2, and an 8 GHz radio power of 10{sup 24.6} W Hz{sup –1}. Combining them, we conclude that acceleration of radio jets and creation of high-energy particles are ongoing in the central engine and that the apparent very radio-loud feature of the source is due to the Doppler boosting effect, resulting in the intrinsic radio loudness being an order of magnitude smaller than the observed values. We also conclude that the pc-scale jet represents recurrent activity from the spectral fitting and the estimated kinematic age of pc- and kpc-scale extended components with different position angles.

  9. A gamma-ray tracking detector for molecular imaging

    International Nuclear Information System (INIS)

    Hall, C.J.; Lewis, R.A.; Helsby, W.I.; Nolan, P.; Boston, A.

    2003-01-01

    A design for a gamma-ray detector for molecular imaging is presented. The system is based on solid-state strip detector technology. The advantages of position sensitivity coupled with fine spectral resolution are exploited to produce a tracking detector for use with a variety of isotopes in nuclear medicine. Current design concepts employ both silicon and germanium layers to provide an energy range from 60 keV to >1 MeV. This allows a reference X-ray image to be collected simultaneously with the gamma-ray image providing accurate anatomical registration. The tracking ability of the gamma-ray detector allows ambiguities in the data set to be resolved which would otherwise cause events to be rejected in standard non-tracking system. Efficiency improvements that high solid angle coverage and the use of a higher proportion of events make time resolved imaging and multi-isotope work possible. A modular detector system, designed for viewing small animals has been accepted for funding

  10. Gamma ray NDA assay system for total plutonium and isotopics in plutonium product solutions

    International Nuclear Information System (INIS)

    Cowder, L.R.; Hsue, S.T.; Johnson, S.S.; Parker, J.L.; Russo, P.A.; Sprinkle, J.K.; Asakura, Y.; Fukuda, T.; Kondo, I.

    1979-01-01

    A LASL-designed gamma-ray NDA instrument for assay of total plutonium and isotopics of product solutions at Tokai-Mura is currently installed and operating. The instrument is, optimally, a densitometer that uses radioisotopic sources for total plutonium measurements at the K absorption edge. The measured transmissions of additional gamma-ray lines from the same radioisotopic sources are used to correct for self-attenuation of passive gamma rays from plutonium. The corrected passive data give the plutonium isotopic content of freshly separated to moderately aged solutions. This off-line instrument is fully automated under computer control, with the exception of sample positioning, and operates routinely in a mode designed for measurement control. A one-half percent precision in total plutonium concentration is achieved with a 15-minute measurement

  11. Utilizing experimentally derived multi-channel gamma-ray spectra for the analysis of airborne data

    International Nuclear Information System (INIS)

    Grasty, R.L.

    1982-01-01

    Gamma-ray spectra derived from measurements on radioactive concrete calibration pads using plywood sheets to simulate the attenuation effect of air have been successfully tested on airbone data. Cesium-137 at 662 keV, from atomic weapons tests was found to contribute significantly to the airborne spectrum. By fitting the experimental spectra, above the cesium energy, to airborne data, significant increases in accuracy were obtained for the measurement of uranium and thorium, compared to the standard 3-window method. By including a cesium spectrum is the analysis of gamma-ray data from a survey carried out in Saskatchewan, it was found that background radiation due to atmospheric bismuth-214 could be measured more reliably than by using a constant over-water background. Similar results were obtained by monitoring low energy lead-214 gamma-rays at 352 keV

  12. Characterization of T cell receptor assembly and expression in a Ti gamma delta-positive cell line

    DEFF Research Database (Denmark)

    Kuhlmann, J; Caspar-Bauguil, S; Geisler, C

    1993-01-01

    - variants of the T cell Lyon were induced and found to produce all of the Ti/CD3 components, with the exception of Ti-delta. Biochemical analysis indicated that: (1) Ti-gamma/CD3 gamma, delta, epsilon complexes were formed in the endoplasmic reticulum in the absence of Ti-delta; (2) the CD3-zeta chain did...

  13. Gamma knife radiosurgery for trigeminal neuralgia. Analysis of a multi institutional study

    International Nuclear Information System (INIS)

    Takanashi, Masami; Ozaki, Yoshimaru; Satou, Kenichi; Oikawa, Mitsuteru; Nakamura, Hirohiko; Fukuoka, Seiji

    2013-01-01

    A multi-institutional study was conducted to evaluate the results of gamma knife radiosurgery (GKRS) for the treatment of trigeminal neuralgia. Eleven hundred and thirty-five patients at 39 centers were analyzed. Three hundred and sixty-nine patients had undergone percutaneous nerve block and 173 patients had undergone microvascular decompression (MVD) prior to GKRS. GKRS was performed for 69.4% of patients targeted at the nerve root entry zone (REZ) and for 20.4% of patients targeted at the retrogasserian region (RGR). The target dose of the GKRS used in the current study varied from 70 to 90 Gy (mean: 77.8 Gy). The median follow-up period after GKRS was 21.1 months (range 1 to 125 months). Six hundred and eighty-nine patients (66%) responded with excellent or good control (pain free), 157 (15%) obtained fair control (more than 50% relief), and 192 (19%) experienced treatment failure. After 3 years, 64% of cases were pain free and 80% had more than 50% pain relief. After 4 years, 37 patients underwent additional GKRS, 36 MVD and 36 percutaneous nerve block. Tolerable hypoesthesia or paresthesia occurred in 129 patients (11%), whereas bothersome symptoms developed in 8 patients (1%). But no patient developed deafferentation pain. Nine patients (1%) complained of dry eye, but no other abnormalities of the cornea and conjunctiva were found on ophthalmological examination. Higher maximum radiosurgical dose was associated with a significantly greater factor of complete pain relief (p=0.0101). GKRS is a safe and effective alternative treatment for trigeminal neuralgia, and is a minimally invasive treatment. In addition it provided benefit to a patient population unwilling or unable to undergo more invasive surgical approaches. (author)

  14. Advances in gamma ray resonant scattering and absorption long-lived isomeric nuclear states

    CERN Document Server

    Davydov, Andrey V

    2015-01-01

    This book presents the basics and advanced topics of research of gamma ray physics. It describes measuring of  Fermi surfaces with gamma resonance spectroscopy and the theory of angular distributions of resonantly scattered gamma rays. The dependence of excited-nuclei average lifetime on the shape of the exciting-radiation spectrum and electron binding energies in the spectra of scattered gamma rays is described. Resonant excitation by gamma rays of nuclear isomeric states with long lifetime leads to the emission and absorption lines. In the book, a new gamma spectroscopic method, gravitational gamma spectrometry, is developed. It has a resolution hundred million times higher than the usual Mössbauer spectrometer. Another important topic of this book is resonant scattering of annihilation quanta by nuclei with excited states in connection with positron annihilation. The application of the methods described is to explain the phenomenon of Coulomb fragmentation of gamma-source molecules and resonant scatt...

  15. Attenuation of neutrons and gamma-rays in homogeneous and multilayered shields

    International Nuclear Information System (INIS)

    Abdo, A.E.; Megahid, R.M.

    1997-01-01

    Measurements were carried-out to compare the attenuation properties of homogeneous shields and shields of two layers and three layers for fast neutrons and total gamma-rays. These were performed by measuring the fast neutron and total gamma-ray spectra behind homogeneous shields of magnetite-limonite, ilmenite-ilmenite and magnetite-magnetite concretes. The two layers assembly consists of iron and one of the above mentioned concretes, while the three layers shield consists of water, iron and one of the previously mentioned concretes. All measurements were carried-out using a neutron-gamma spectrometer with stilbene scintillator coupled to a fast photo multi player tube. Separation between pulses of recoil protons and recoil electrons was achieved by a pulse shape discrimination technique. 3 tabs., 10 figs., 13 refs

  16. Human gamma oscillations during slow wave sleep.

    Directory of Open Access Journals (Sweden)

    Mario Valderrama

    Full Text Available Neocortical local field potentials have shown that gamma oscillations occur spontaneously during slow-wave sleep (SWS. At the macroscopic EEG level in the human brain, no evidences were reported so far. In this study, by using simultaneous scalp and intracranial EEG recordings in 20 epileptic subjects, we examined gamma oscillations in cerebral cortex during SWS. We report that gamma oscillations in low (30-50 Hz and high (60-120 Hz frequency bands recurrently emerged in all investigated regions and their amplitudes coincided with specific phases of the cortical slow wave. In most of the cases, multiple oscillatory bursts in different frequency bands from 30 to 120 Hz were correlated with positive peaks of scalp slow waves ("IN-phase" pattern, confirming previous animal findings. In addition, we report another gamma pattern that appears preferentially during the negative phase of the slow wave ("ANTI-phase" pattern. This new pattern presented dominant peaks in the high gamma range and was preferentially expressed in the temporal cortex. Finally, we found that the spatial coherence between cortical sites exhibiting gamma activities was local and fell off quickly when computed between distant sites. Overall, these results provide the first human evidences that gamma oscillations can be observed in macroscopic EEG recordings during sleep. They support the concept that these high-frequency activities might be associated with phasic increases of neural activity during slow oscillations. Such patterned activity in the sleeping brain could play a role in off-line processing of cortical networks.

  17. A Modular Pipelined Processor for High Resolution Gamma-Ray Spectroscopy

    Science.gov (United States)

    Veiga, Alejandro; Grunfeld, Christian

    2016-02-01

    The design of a digital signal processor for gamma-ray applications is presented in which a single ADC input can simultaneously provide temporal and energy characterization of gamma radiation for a wide range of applications. Applying pipelining techniques, the processor is able to manage and synchronize very large volumes of streamed real-time data. Its modular user interface provides a flexible environment for experimental design. The processor can fit in a medium-sized FPGA device operating at ADC sampling frequency, providing an efficient solution for multi-channel applications. Two experiments are presented in order to characterize its temporal and energy resolution.

  18. Unilateral irradiation of pigs in a mixed neutrons+gamma field. Early results

    International Nuclear Information System (INIS)

    Lemaitre, Guy; Maas, Jean.

    1982-08-01

    Pigs (16-20kg) were irradiated with 60 Co gamma or in a mixed field (neutron + gamma from the pulsed reactor SILENE). Pigs were unilaterally exposed by the left side. Each experimental group was composed of twelve animals and one control. Within the dose range explored (reference dose is mid-line tissue dose): 4-9.8 Gy of gamma rays only; 4.6 - 5.7 Gy of neutrons and gamma rays, pigs presented the haematopioetic form of the acute radiation sickness. At 5 Gy mixed field was more harmful than gamma rays only. Therefore the numerical value of neutron RBE (lethality 50 p cent within 30 days) is more than one. Experiments will be carried out in order to determine RBE values more accurately. Bone marrow dose will also be determined [fr

  19. The host galaxy of the gamma-ray narrow-line Seyfert 1 galaxy 1H 0323+342

    Energy Technology Data Exchange (ETDEWEB)

    León Tavares, J.; Chavushyan, V.; Puerari, I.; Patiño-Alvarez, V.; Carramiñana, A.; Carrasco, L.; Guichard, J.; Olguín-Iglesias, A.; Valdes, J. [Instituto Nacional de Astrofísica Óptica y Electrónica (INAOE), Apartado Postal 51 y 216, 72000 Puebla (Mexico); Kotilainen, J. [Finnish Centre for Astronomy with ESO (FINCA), University of Turku, Väisäläntie 20, FI-21500 Piikkiö (Finland); Añorve, C. [Facultad de Ciencias de la Tierra y del Espacio (FACITE) de la Universidad Autónoma de Sinaloa, Blvd. de la Americas y Av. Universitarios S/N, Ciudad Universitaria, C.P. 80010, Culiacán Sinaloa (Mexico); Cruz-González, I. [Instituto de Astronomía, Universidad Nacional Autónoma de México, Ap. 70-264, 04510 DF (Mexico); Antón, S. [Instituto de Astrofísica de Andalucía-CSIC, E-18008 Granada (Spain); Karhunen, K.; Sanghvi, J., E-mail: leon.tavares@inaoep.mx [Tuorla Observatory, Department of Physics and Astronomy, University of Turku, FI-20100 Turku (Finland)

    2014-11-01

    We present optical and near-infrared (NIR) imaging data of the radio-loud, narrow-line Seyfert 1 galaxy 1H 0323+342, which shows intense and variable gamma-ray activity discovered by the Fermi satellite with the Large Area Telescope. Near-infrared and optical images are used to investigate the structural properties of the host galaxy of 1H 0323+342; this together with optical spectroscopy allows us to examine its black hole mass. Based on two-dimensional (2D) multiwavelength surface-brightness modeling, we find that statistically, the best model fit is a combination of a nuclear component and a Sérsic profile (n ∼ 2.8). However, the presence of a disk component (with a small bulge n ∼ 1.2) also remains a possibility and cannot be ruled out with the present data. Although at first glance a spiral-arm-like structure is revealed in our images, a 2D Fourier analysis of the imagery suggests that this structure corresponds to an asymmetric ring, likely associated with a recent violent dynamical interaction. We discuss our results in the context of relativistic jet production and galaxy evolution.

  20. Radiative decay of the eta-, eta'-mesons in the nonlocal quark model. [eta(eta'). --> gamma gamma. ; eta. -->. pi. /sup +/. pi. /sup -/. gamma. ; eta. -->. pi. /sup 0/2. gamma. ; eta'. -->. rho/sup 0/. gamma. ; eta'. -->. omega gamma. ;. pi. /sup 0/. -->. gamma. e/sup +/e/sup -/; eta(eta'). -->. gamma mu. /sup +/. mu. /sup -/

    Energy Technology Data Exchange (ETDEWEB)

    Efimov, G V; Ivanov, M A; Nogovitsyn, E A [Joint Inst. for Nuclear Research, Dubna (USSR)

    1981-07-01

    P..--> gamma gamma.. (P=..pi../sup 0/, eta, eta'), eta..--> pi../sup +/..pi../sup -/..gamma.., eta..--> pi../sup 0/..gamma gamma.., eta/sup 1/..-->..V..gamma.. (V=rho/sup 0/, ..omega..), p..--> gamma..l/sup +/l/sup -/ (p=..pi../sup 0/, eta, eta') radiation decays are studied for testing the applicability of the non-local quark model for description of the experimental data. The Feynman diagrams of these decays are presented, values of the widths of the Veta..--> gamma gamma.., eta..--> pi../sup +/..pi../sup -/..gamma.., eta..--> pi../sup 0/..gamma gamma.., eta'..--> gamma gamma.., eta'..-->..rho/sup 0/..gamma.., eta'..--> omega gamma.. decays are calculated and given in the form of a table. Calculations are carried out for two values of the eta eta'-crossing angle: THETA=-11 deg and -18 deg. Values of invariant amplitudes of these decays are determined for ..pi../sup 0/..--> gamma..e/sup +/e/sup -/, eta..--> gamma mu../sup +/..mu../sup -/, eta'..--> gamma mu../sup +/..mu../sup -/ decays at THETA=-11 deg and -18 deg. The best agreement with the experimental data is noted to take place at THETA=-11 deg, the determined width of the eta..--> pi../sup 0/..gamma gamma.. decays is underestimated as compared with the experimental one.

  1. EPR study on tomatoes before and after gamma-irradiation

    International Nuclear Information System (INIS)

    Aleksieva, K.; Georgieva, L.; Tzvetkova, E.; Yordanov, N.D.

    2009-01-01

    The results from the EPR studies on fresh, air-dried and lyophilized tomato samples before and after gamma-irradiation are reported. Before irradiation fresh and air-dried tomatoes exhibit one singlet EPR line characterized with common g-factor of 2.0048±0.0005, whereas freeze-dried tomato does not show any EPR spectrum. After irradiation, a typical 'cellulose-like' triplet EPR spectrum appears in all samples, attributed to cellulose free radicals, generated by gamma-irradiation. It consists of intense central line with g=2.0048±0.0005 and two weak satellite lines separated ca. 3 mT left and right of it. In air-dried and lyophilized tomatoes the 'cellulose-like' EPR spectrum is superimposed by an additional partly resolved carbohydrate spectrum. Fading measurements of the radiation-induced EPR signals indicate that the intensity of the EPR spectra of air-dried and freeze-dried tomato are reduced to about 50% after 50 days, whereas those of fresh irradiated tomatoes kept at 4 o C fade completely in 15 days. The reported results unambiguously show that the presence of two satellite lines in the EPR 'cellulose-like' spectra of tomato samples can be used for identification of radiation processing.

  2. Time-of-flight spectrometer for the measurement of gamma correlated neutron spectra

    International Nuclear Information System (INIS)

    Andriashin, A.V.; Devkin, B.V.; Lychagin, A.A.; Minko, J.V.; Mironov, A.N.; Nesterenko, V.S.; Sztaricskai, T.; Petoe, G.; Vasvary, L.

    1986-01-01

    A time-of-flight spectrometer for the measurement of gamma correlated neutron spectra from (n,xnγ) reactions is described. The operation and the main parameters are discussed. The resolution in the neutron channel is 2.2 ns/m at the 150 keV neutron energy threshold. A simultaneous measurement of the time-of-flight and amplitude distributions makes it possible to study gamma correlated neutron spectra as well as the prompt gamma spectra in coincidence with selected energy neutrons. In order to test the spectrometer, measurements of the neutron spectrum in coincidence with the 846 keV gamma line of 56 Fe were carried out at an incident neutron energy of 14.1 MeV. (Auth.)

  3. Gamma multi-detectors and nuclear structure studies: search for superdeformed structures in {sup 147}Gd and {sup 144}Gd isotopes using Crystal Castle; simulation calculations for EUROGAM multi-detector definition; Multidetecteurs gamma et etudes de structure nucleaire: recherche avec le Chateau de Cristal de structures superdeformees dans les isotopes {sup 147}Gd et {sup 144}Gd; calculs de simulation pour la definition du multidetecteur EUROGAM

    Energy Technology Data Exchange (ETDEWEB)

    France, G de

    1992-12-31

    Computer simulations have been used for the calculation of the new generation of 4 {pi}{gamma} multi-detectors (Castle Crystal) of EUROGAM system (phase I and II). Two superdeformed bands (I and II), comprising 16 and 13 transitions respectively, have been described for {sup 147}Gd nucleus during the {sup 122}Sn({sup 30}Si,5n) fusion-evaporation reaction in a 155 MeV bombardment energy. Dynamic inertia momentum similarities and gamma transition energy similarities have been observed between band I and {sup 148}Gd nucleus and between band II and {sup 146}Gd nucleus, respectively. These similarities can be related to a pseudo-spin symmetry. Calculations suggest the existence of an octupolar susceptibility in this mass region. {sup 144}Gd nucleus has been studied using {sup 120}Sn({sup 29}Si,5n) fusion-evaporation reaction in a 155 MeV bombardment energy and using {sup 100}Mo({sup 48}Ti,4n) reactions in a 200 MeV bombardment energy. {gamma}-{gamma} coincidences have revealed the existence of a 58 keV width valley in the matrix representation compatible with theoretical predictions. In spite of the evidence for about ten transitions during these experiments, no superdeformed structure has been demonstrated for {sup 144}Gd nucleus. (J.S.). 87 refs., 57 figs., 41 tabs.

  4. Multi-National Banknote Classification Based on Visible-light Line Sensor and Convolutional Neural Network.

    Science.gov (United States)

    Pham, Tuyen Danh; Lee, Dong Eun; Park, Kang Ryoung

    2017-07-08

    Automatic recognition of banknotes is applied in payment facilities, such as automated teller machines (ATMs) and banknote counters. Besides the popular approaches that focus on studying the methods applied to various individual types of currencies, there have been studies conducted on simultaneous classification of banknotes from multiple countries. However, their methods were conducted with limited numbers of banknote images, national currencies, and denominations. To address this issue, we propose a multi-national banknote classification method based on visible-light banknote images captured by a one-dimensional line sensor and classified by a convolutional neural network (CNN) considering the size information of each denomination. Experiments conducted on the combined banknote image database of six countries with 62 denominations gave a classification accuracy of 100%, and results show that our proposed algorithm outperforms previous methods.

  5. Brevion: the new small-scale industrial gamma irradiator

    International Nuclear Information System (INIS)

    McKinney, Dan; Perrins, Robert; Gibson, Wayne; Levesque, Daniel

    2002-01-01

    The economical processing of low-volume products has been a challenge to the gamma industry since inception, influencing customers to send their products to contractors or choose alternative technologies. With the introduction of the Brevion irradiator (patent pending), economical gamma processing of low annual volume product lines is now possible. This innovative design is specifically targeted at plants processing product volumes of up to 20,000 m 3 /yr. Brevion provides good cobalt efficiency and good dose uniformity, thus processing these volumes efficiently and economically. The Brevion facility has the distinct advantage of a low capital cost, compared to medium-sized automatic tote plants, while maintaining similar performance. Lead-time for the construction phase is also considerably shorter, resulting in significantly lower start-up costs. Companies with low-volume product lines can now achieve the control provided by in-house processing, and eliminate transportation time and costs associated with shipping products off-site

  6. Topics in Astrophysical X-Ray and Gamma Ray Spectroscopy. Ph.D. Thesis - Maryland Univ.

    Science.gov (United States)

    Bussard, R. W.

    1978-01-01

    A number of topics relating to astrophysical observations that have already been made or are currently planned of spectral features, mostly emission lines, in the X-ray and gamma ray region of the electromagnetic spectrum are investigated. These topics include: the production of characteristic X-ray and gamma ray lines by nonthermal ions, spectral features induced by processes occurring in strong magnetic fields, and the positron annihilation line at 0.5 MeV. The rate of X-ray production at 6.8 keV by the 2p to 1s transition in fast hydrogen- and helium-like iron ions, following both electron capture to excited levels and collisional excitation is calculated. The cross section for electron-ion Coulomb collisions in strong fields is also calculated.

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

    Science.gov (United States)

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

    1987-12-15

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

  8. Selection of gamma-ray induced salt tolerant rice mutants by in vitro mutagenesis

    International Nuclear Information System (INIS)

    Kim, Dong Sub; Chun, Jae Beom; Lee, Kyung Jun; Kim, Jin Baek; Kim, Sang Hoon; Yun, Song Jong; Kang, Si Yong

    2010-01-01

    The present study had been performed to select the salt tolerant rice mutant lines through an in vivo and in vitro mutagenesis with a gamma-ray. The physiological responses such as MDA and chlorophyll of the selected salt mutant lines were investigated under salt stress. For the selection of the salt tolerant rice mutants by in vitro mutagenesis with gamma-ray, we conducted a second selection procedure with 1,500 mutant lines induced from the original cv. Dongan (wild-type, WT): Ist, selection under a nutrient solution with 171 mM NaCI: 2nd, selection under in vitro conditions. Based on a growth comparison of the entries, out of mutant lines, the putative 2 salt tolerant rice mutant lines, ST-495 and ST-532, were selected. The 2 ST-lines had a lower malonaldehyde (MDA) contents than wild-type (WT) during salt stress. The survival rate of the WT, ST-495 and ST-532 were 36.6%, 70% and 50% in 171 mM NaCI, respectively. The chlorophyll and carotenoid contents were decreased more in a WT plant than the two selected mutant lines. These rice mutant lines will be released for cultivation at the reclaimed land and used as a control plot for genetic research about salt tolerance

  9. Selection of gamma-ray induced salt tolerant rice mutants by in vitro mutagenesis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Sub; Chun, Jae Beom; Lee, Kyung Jun; Kim, Jin Baek; Kim, Sang Hoon; Yun, Song Jong; Kang, Si Yong [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2010-06-15

    The present study had been performed to select the salt tolerant rice mutant lines through an in vivo and in vitro mutagenesis with a gamma-ray. The physiological responses such as MDA and chlorophyll of the selected salt mutant lines were investigated under salt stress. For the selection of the salt tolerant rice mutants by in vitro mutagenesis with gamma-ray, we conducted a second selection procedure with 1,500 mutant lines induced from the original cv. Dongan (wild-type, WT): Ist, selection under a nutrient solution with 171 mM NaCI: 2nd, selection under in vitro conditions. Based on a growth comparison of the entries, out of mutant lines, the putative 2 salt tolerant rice mutant lines, ST-495 and ST-532, were selected. The 2 ST-lines had a lower malonaldehyde (MDA) contents than wild-type (WT) during salt stress. The survival rate of the WT, ST-495 and ST-532 were 36.6%, 70% and 50% in 171 mM NaCI, respectively. The chlorophyll and carotenoid contents were decreased more in a WT plant than the two selected mutant lines. These rice mutant lines will be released for cultivation at the reclaimed land and used as a control plot for genetic research about salt tolerance.

  10. Software programmable multi-mode interface for nuclear-medical imaging

    International Nuclear Information System (INIS)

    Zubal, I.G.; Rowe, R.W.; Bizais, Y.J.C.; Bennett, G.W.; Brill, A.B.

    1982-01-01

    An innovative multi-port interface allows gamma camera events (spatial coordinates and energy) to be acquired concurrently with a sampling of physiological patient data. The versatility of the interface permits all conventional static, dynamic, and tomographic imaging modes, in addition to multi-hole coded aperture acquisition. The acquired list mode data may be analyzed or gated on the basis of various camera, isotopic, or physiological parameters

  11. Software Product Lines for Multi-Cloud Microservices-Based Applications

    OpenAIRE

    Sousa , Gustavo; Rudametkin , Walter; Duchien , Laurence

    2016-01-01

    International audience; Multi-cloud computing is the use of resources and services from multiple independent cloud providers. It is used to avoid vendor lock-in, comply with location regulations, and optimize reliability, performance and costs. Microservices is an architectural style becoming increasingly used in cloud computing as it allows for better resources usage. However, building multi-cloud systems is a very complex and time consuming task, which calls for automation and supporting to...

  12. Twelve Years of Education and Public Outreach with the Fermi Gamma-ray Space Telescope

    Science.gov (United States)

    Cominsky, Lynn R.; McLin, K. M.; Simonnet, A.; Fermi E/PO Team

    2013-04-01

    During the past twelve years, NASA's Fermi Gamma-ray Space Telescope has supported a wide range of Education and Public Outreach (E/PO) activities, targeting K-14 students and the general public. The purpose of the Fermi E/PO program is to increase student and public understanding of the science of the high-energy Universe, through inspiring, engaging and educational activities linked to the mission’s science objectives. The E/PO program has additional more general goals, including increasing the diversity of students in the Science, Technology, Engineering and Mathematics (STEM) pipeline, and increasing public awareness and understanding of Fermi science and technology. Fermi's multi-faceted E/PO program includes elements in each major outcome category: ● Higher Education: Fermi E/PO promotes STEM careers through the use of NASA data including research experiences for students and teachers (Global Telescope Network), education through STEM curriculum development projects (Cosmology curriculum) and through enrichment activities (Large Area Telescope simulator). ● Elementary and Secondary education: Fermi E/PO links the science objectives of the Fermi mission to well-tested, customer-focused and NASA-approved standards-aligned classroom materials (Black Hole Resources, Active Galaxy Education Unit and Pop-up book, TOPS guides, Supernova Education Unit). These materials have been distributed through (Educator Ambassador and on-line) teacher training workshops and through programs involving under-represented students (after-school clubs and Astro 4 Girls). ● Informal education and public outreach: Fermi E/PO engages the public in sharing the experience of exploration and discovery through high-leverage multi-media experiences (Black Holes planetarium and PBS NOVA shows), through popular websites (Gamma-ray Burst Skymap, Epo's Chronicles), social media (Facebook, MySpace), interactive web-based activities (Space Mysteries, Einstein@Home) and activities by

  13. Quantifying the benefits of ultrahigh energy resolution for Gamma-ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Drury, Owen B.; Terracol, Stephane F.; Friedrich, Stephan [Advanced Detector Group, Lawrence Livermore National Laboratory, L-270, Livermore CA 94550 (United States)

    2005-03-01

    Cryogenic Gamma-ray spectrometers operating at temperatures of {proportional_to}0.1 K provide an order of magnitude better energy resolution than conventional germanium detectors. Ultra-high energy resolution improves the accuracy of non-destructive analysis of nuclear materials, since a better separation of lines reduces statistical errors as well as systematic errors from background subtraction and efficiency correction. We are developing cryogenic Gamma-spectrometers based on bulk tin absorbers and superconducting molybdenum-copper sensors for nuclear forensics and non-proliferation applications. Here we quantify the improvements in accuracy for isotope analysis with cryogenic detectors in terms of detector performance for different cases of line separation, line intensity ratios and background levels. Precise measurements of isotope ratios are crucial in the context of nuclear attribution, since they provide signatures of composition, age, origin, intended purpose and processing history of illicit nuclear materials. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  14. S100A7 (Psoriasin), highly expressed in Ductal Carcinoma In Situ (DCIS), is regulated by IFN-gamma in mammary epithelial cells

    International Nuclear Information System (INIS)

    Petersson, Stina; Bylander, Anna; Yhr, Maria; Enerbäck, Charlotta

    2007-01-01

    The aim of the present work was to explore signal transduction pathways used in the regulation of S100A7 (psoriasin). Members of the S100 gene family participate in many important cellular functions. Psoriasin, S100A8 (calgranulin A) and S100A9 (calgranulin B) are expressed in ductal carcinoma in situ (DCIS), as well as in the hyperproliferative skin disease, psoriasis. In the latter condition, a disturbance in the STAT pathway has recently been reported. This pathway is implicated in the regulation of IFN-gamma, widely recognized as a key cytokine in psoriasis. IFN-gamma also exerts anti-tumor action in a number of tumor cell types, including breast cancer. We therefore examined the effect of IFN-gamma and STAT-signaling on the psoriasin expression. We established a TAC2 mouse mammary epithelial cell line with tetracycline-inducible psoriasin expression (Tet-Off). Viability in cell culture was estimated using MTS assay. Protein and gene expression were evaluated by Western blotting and quantitative real-time PCR. Statistical analyses were assessed using a one-tailed, paired t-test. We report the downregulation of psoriasin by IFN-gamma in the MDA-MB-468 breast cancer cell line, as well as the downregulation of psoriasin induced by anoikis in cell lines derived from different epithelial tissues. In contrast, IFN-gamma had no suppressive effect on calgranulin A or calgranulin B. IFN-gamma is an important activator of the STAT1 pathway and we confirmed an active signaling pathway in the cell lines that responded to IFN-gamma treatment. In contrast, in the SUM190 breast carcinoma cell line, IFN-gamma did not suppress the expression of endogenous psoriasin. Moreover, a reduced phosphorylation of the STAT1 protein was observed. We showed that IFN-gamma treatment and the inhibition of the transcription factor NFkappaB had a synergistic effect on psoriasin levels. Finally, in TAC2 cells with tetracycline-induced psoriasin expression, we observed the increased viability of

  15. Application of gamma-spectrometry to post irradiation examination

    International Nuclear Information System (INIS)

    Kim, S.K.; Huh, Y.H.; Park, K.J.

    1982-01-01

    A areat variety of nuclear gamma rays emitted from fission and activation products of spent nuclear fuel contains much information that can be elicited without affecting the integrity of the fuel elements. In the present work, a versatile code CAERI was developed which locates peaks and calculates their areas for X-rays as well as gamma rays using elegant features of some widely used programs for gamma ray peak fitting. CAERI coded in FORTRAN used infinite series approximation more accurate than other workers' various, simple, piecewise series approximations for evaluation of the Voigt function which represents the X-ray peak with nonneglible natural line width. CAERI can handle even a complex multiplet consisting of peaks from X-rays and rays in arbitrary mixture, which one often encounters in the isotopic analysis of heavy elements such as U and Pu. (Author)

  16. Study, simulation and modelling of a gamma photon detector placed on an integral-type eccentric orbit; Etude, simulation et modelisation d'un detecteur de photons gamma place sur une orbite excentrique de type integral

    Energy Technology Data Exchange (ETDEWEB)

    Diallo, N

    1999-07-01

    Gamma-ray lines are the signature of nuclear reactions and other high-energy processes that take place in the Universe. Their measurement and study provide invaluable information on many important problems in high energy astrophysics, including particle acceleration, physics of compact objects and nucleosynthesis. However the observation of astronomical gamma-ray sources has to be performed above the atmosphere because the Earth's atmosphere is opaque to gamma-rays. Unfortunately at these altitudes, spatial high energy electromagnetic radiation (X and gamma rays) detectors are exposed to intense parasite fluxes of radiation and particles induced by primary galactic cosmic rays. These fluxes as well radiation and secondary particles they generate, constitute a considerable source of background which limits their performances. Our study has been done in the framework of the INTEGRAL mission, a gamma-ray astronomy mission of the European Space Agency. INTEGRAL is devoted to the observation of celestial gamma-ray sources. It consists of two main instruments: an imager IBIS and a high resolution germanium spectrometer SPI ({delta}E/E = 1.6 10{sup -3} at 1.3 MeV). We studied the hadronic component of the SPI background. This component is due to the radioactive decay of unstable nuclides produced by the interactions of cosmic-ray protons with the materials of SPI. It consists of a continuum with gamma ray lines superimposed. To study nuclear processes, Monte Carlo simulations have been performed with the nuclear code TIERCE developed at CEA/DAM. We used the GEANT Monte Carlo code developed at CERN to simulate the germanium detectors response. Background reduction techniques as PSD (Pulse Shape Discrimination) and energetic signatures have been applied in well chosen energy ranges to reduce the background. and improve the SPI sensitivity. With the estimated SPI narrow-line sensitivity level, SPI would be able to detect many gamma ray limes emitted in the active

  17. COMPTEL gamma-ray observations of the C4 solar flare on 20 January 2000

    International Nuclear Information System (INIS)

    Young, C.A.; Arndt, M.B.; Bennett, K.; Winkler, C.; Connors, A.; Debrunner, H.; Diehl, R.; Rank, G.; Schoenfelder, V.; McConnell, M.; Miller, R.S.; Ryan, J.M.

    2001-01-01

    The 'Pre-SMM' (Vestrand and Miller 1998) picture of gamma-ray line (GRL) flares was that they are relatively rare events. This picture was quickly put in question with the launch of the Solar Maximum Mission (SMM). Over 100 GRL flares were seen with sizes ranging from very large GOES class events (X12) down to moderately small events (M2). It was argued by some (Bai 1986) that this was still consistent with the idea that GRL events are rare. Others, however, argued the opposite (Vestrand 1988; Cliver, Crosby and Dennis 1994), stating that the lower end of this distribution was just a function of SMM's sensitivity. They stated that the launch of the Compton Gamma-ray Observatory (CGRO) would in fact continue this distribution to show even smaller GRL flares. In response to a BACODINE cosmic gamma-ray burst alert, COMPtonTELescope on the CGRO recorded gamma rays above 1 MeV from the C4 flare at 0221 UT 20 January 2000. This event, though at the limits of COMPTEL's sensitivity, clearly shows a nuclear line excess above the continuum. Using new spectroscopy techniques we were able to resolve individual lines. This has allowed us to make a basic comparison of this event with the GRL flare distribution from SMM and also compare this flare with a well-observed large GRL flare seen by OSSE

  18. The multi-step prompt particle emission from fission fragments

    International Nuclear Information System (INIS)

    Zhivopistsev, A.; Oprea, C.; Oprea, I.

    2003-01-01

    The purpose of this work is the study of non-equilibrium high-energy gamma emission from 252 Cf. In the framework of the formalism of statistical multi-step compound processes in nuclear reactions. A relation was found between the shape of the high-energy part of the gamma spectrum and different mechanisms of excitation of the fission fragments. Agreement with experimental data for different groups of fission fragments was obtained. The analysis of the experimental high-energy part of gamma spectra yields information about the mechanism of excitation of fission fragments. The influence of dissipation of the deformation excess on intrinsic excitation of fission fragments was studied. (authors)

  19. Coupling of RELAP5-3D and GAMMA codes for Nuclear Hydrogen System Analysis

    International Nuclear Information System (INIS)

    Jin, Hyung Gon

    2007-02-01

    RELAP5-3D is one of the most important system analysis codes in nuclear field, which has been developed for best-estimate transient simulation of light water reactor coolant systems during postulated accidents. The GAMMA code is a multi-dimensional multi-component mixture analysis code with the complete set of chemical reaction models which is developed for safety analysis of HTGR (High Temperature Gas Cooled Reactor) air-ingress. The two codes, RELAP5-3D and GAMMA, are coupled to be used for nuclear-hydrogen system analysis, which requires the capability of the analysis of multi-component gas mixture and two-phase flow. In order to couple the two codes, 4 steps are needed. Before coupling, the GAMMA code was transformed into DLL (dynamic link liberally) from executive type and RELAP5-3D was recompiled into Compaq Visual Fortran environments for our debugging purpose. As the second step, two programs - RELAP5-3D and GAMMA codes - must be synchronized in terms of time and time step. Based on that time coupling, the coupled code can calculate simultaneously. Time-step coupling had been accomplished successfully and it is tested by using a simple test input. As a next step, source-term coupling was done and it was also tested in two different test inputs. The fist case is a simple test condition, which has no chemical reaction. And the other test set is the chemical reaction model, including four non-condensable gas species, which are He, O2, CO, CO2. Finally, in order to analyze combined cycle system, heat-flux coupling has been made and a simple heat exchanger model was demonstrated

  20. Induction of Genetic Variation with Recurrent Gamma Radiation in Centipedegrass (Eremochloa ophiuroides)

    International Nuclear Information System (INIS)

    Lim Keun- Bal; Rim Yong-Woo

    1998-01-01

    Centipedegrass (Eremochloa ophiuroides) is a popular lawn grass in the southeastern USA. It has a naturally light green color and grows well on a wide range of soil types. Studies show limited morphological variation present in centipedegrass germplasm. To obtain the high morphological variation, plants were established from the irradiated seed at 10 Kr, allowed to interpollinate and harvested bulk seed, and then irradiated again for the next cycles. Morphological characteristics were measured in the 5 genetic varition lines (TC201:cv. Common and non irradiated, TC202:4th cycles, TC241:6th cycles, TC306:8th cycles, and TC318:5th cycles) induced by recurrent gamma radiation. The ranges of variation of recurrently radiated centipedegrass lines TC202, TC241, and TC306 except TC318(TifBlair) for the stolons per plant, total stolon length per plant, longest stolon length, leaf length and width at top-most exposed internode were wider than those of non-irradiated line (TC201). Recurrent gamma radiation was very effective to enlarge the ranges of variation of morphological characteristics in reproductive organ like stolons of centipedegrass. The effect of quantity of gamma ray irradiation cycles on the means and ranges of variation in the morphological characteristics of centipedegrass was not regularly tended

  1. Achieving Higher Accuracy in the Gamma-Ray Spectrocopic Assay of Holdup

    International Nuclear Information System (INIS)

    Russo, P.A.; Wenz, T.R.; Smith, S.E.; Harris, J.F.

    2000-01-01

    Gamma-ray spectroscopy is an important technique for the measurement of quantities of nuclear material holdup in processing equipment. Because the equipment in large facilities dedicated to uranium isotopic enrichment, uranium/plutonium scrap recovery or various stages of fuel fabrication is extensive, the total holdup may be large by its distribution alone, even if deposit thicknesses are small. Good accountability practices require unbiased measurements with uncertainties that are as small as possible. This paper describes new procedures for use with traditional holdup analysis methods based on gamma-ray spectroscopy. The procedures address the two sources of bias inherent in traditional gamma-ray measurements of holdup. Holdup measurements are performed with collimated, shielded gamma-ray detectors. The measurement distance is chosen to simplify the deposit geometry to that of a point, line or area. The quantitative holdup result is based on the net count rate of a representative gamma ray. This rate is corrected for contributions from room background and for attenuation by the process equipment. Traditional holdup measurements assume that the width of the point or line deposit is very small compared to the measurement distance, and that the self-attenuation effects can be neglected. Because each point or line deposit has a finite width and because self-attenuation affects all measurements, bias is incurred in both assumptions. In both cases the bias is negative, explaining the systematically low results of gamma-ray holdup measurements. The new procedures correct for bias that arises from both the finite-source effects and the gamma-ray self-attenuation. The procedures used to correct for both of these effects apply to the generalized geometries. One common empirical parameter is used for both corrections. It self-consistently limits the total error incurred (from uncertain knowledge of this parameter) in the combined correction process, so that it is

  2. QCL seeded, ns-pulse, multi-line, CO2 laser oscillator for laser-produced-plasma extreme-UV source

    Science.gov (United States)

    Nowak, Krzysztof Michał; Suganuma, Takashi; Kurosawa, Yoshiaki; Ohta, Takeshi; Kawasuji, Yasufumi; Nakarai, Hiroaki; Saitou, Takashi; Fujimoto, Junichi; Mizoguchi, Hakaru; Sumitani, Akira; Endo, Akira

    2017-01-01

    Successful merger of state-of-the-art, semiconductor quantum-cascade lasers (QCL), with the mature CO2 laser technology, resulted in a delivery of highly-desired qualities of CO2 laser output that were not available previously without much effort. These qualities, such as multi-line operation, excellent spectro-temporal stability and pulse waveform control, became available from a single device of moderate complexity. This paper describes the operation principle and the unique properties of the solid{state seeded CO2 laser, invented for an application in laser-produced-plasma (LPP), extreme-UV (EUV) light source.

  3. Analysis of ({sup 7}F{sub 0}){gamma}{sub 1g}{yields}({sup 5}D{sub 2}){gamma}{sub 5g}, {gamma}{sub 3g} and ({sup 7}F{sub 0}){gamma}{sub 1g}{yields}({sup 5}L{sub 6}){gamma}{sub 1g}, a{gamma}{sub 5g} two-photon absorption spectra of Cs{sub 2}NaYF{sub 6}:Eu{sup 3+}

    Energy Technology Data Exchange (ETDEWEB)

    Ning Lixin; Wang Dianyuan; Xia Shangda [Structure Research Laboratory, Academica Sinica, Department of Physics, University of Science and Technology of China, Heifei, Anhui (China); Thorne, Jonathan R.G. [Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford (United Kingdom); Tanner, Peter A. [Department of Biology and Chemistry, City University of Hong Kong, Kowloon (China)

    2002-04-15

    The direct calculation of transition line strengths and relative intensities is presented for two intraconfigurational two-photon absorption (TPA) transitions of Eu{sup 3+} in the cubic Cs{sub 2}NaYF{sub 6} host. Crystal field wavefunctions were utilized for the initial and final f{sup N}-electron states and various approaches were used in constructing all the 4f{sup N-1} 5d{sup 1} intermediate-state wavefunctions. The calculated relative intensities of the ({sup 7}F{sub 0}) {gamma}{sub 1g}{yields}({sup 5}D{sub 2}){gamma}{sub 5g}, {gamma}{sub 3g} TPA transitions are in reasonable agreement with experiment. The neglect of J-mixing in the initial state has only a small effect upon the calculation, whereas the neglect of spin-orbit couplings within the initial and terminal states drastically reduces the calculated transition linestrengths, but does not markedly change the intensity ratios. In the case of the ({sup 7}F{sub 0}){gamma}{sub 1g}{yields}({sup 5}L{sub 6}){gamma}{sub 1g}, a{gamma}{sub 5g} transitions, serious discrepancies between experiment and theory are found if the intermediate states are constructed from a 4f{sup 5} core comprising free ion states and the 5d{sup 1} crystal field states. Satisfactory agreement is, however, found when the 4f{sup 5} crystal field states are utilized in constructing the intermediate states. The contributions to the transition moment have been evaluated for various Hamiltonian terms and the results are discussed. (author)

  4. Rat embryo cells immortalized with transfected oncogenes are transformed by gamma irradiation.

    Science.gov (United States)

    Endlich, B; Salavati, R; Sullivan, T; Ling, C C

    1992-12-01

    Cesium-137 gamma rays were used to transform rat embryo cells (REC) which were first transfected with activated c-myc or c-Ha-ras oncogenes to produce immortal cell lines (REC:myc and REC:ras). When exposed to 6 Gy of 137Cs gamma rays, some cells became morphologically transformed with focus formation frequencies of approximately 3 x 10(-4) for REC:myc and approximately 1 x 10(-4) for REC:ras, respectively. Cells isolated from foci of gamma-ray-transformed REC:myc (REC:myc:gamma) formed anchorage-independent colonies and were tumorigenic in nude mice, but foci from gamma-ray-transformed REC:ras (REC:ras:gamma) did not exhibit either of these criteria of transformation. Similar to the results with gamma irradiation, we observed a sequence-dependent phenomenon when myc and ras were transfected into REC, one at a time. REC immortalized by ras transfection were not converted to a tumorigenic phenotype by secondary transfection with myc, but REC transfected with myc were very susceptible to transformation by subsequent ras transfection. This suggests that myc-immortalized cells are more permissive to transformation via secondary treatments. In sequentially transfected REC, myc expression was high whether it was transfected first or second, whereas ras expression was highest when the ras gene was transfected secondarily into myc-containing REC. Molecular analysis of REC:ras:gamma transformants showed no alterations in structure of the transfected ras or of the endogenous ras, myc, p53, or fos genes. The expression of ras and p53 was increased in some isolates of REC:ras:gamma, but myc and fos expression were not affected. Similarly, REC:myc:gamma transformants did not demonstrate rearrangement or amplification of the transfected or the endogenous myc genes, or of the potentially cooperating Ha-, Ki-, or N-ras genes. Northern hybridization analysis revealed increased expression of N-ras in two isolates, REC:myc:gamma 33 and gamma 41, but no alterations in the expression

  5. 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

  6. Two-quantum Doppler-free induced gamma emission

    International Nuclear Information System (INIS)

    Zadernovsky, A.A.

    1999-01-01

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

  7. Amdel on-line analyser at Rooiberg Tin Limited

    International Nuclear Information System (INIS)

    Owen, T.V.

    1987-01-01

    An Amdel on line analysis system was installed on the 'A' mine tin flotation plant at Rooiberg in April 1984. The motivation for the installation was made on account of the large variations in the feed grade to the plant and the resulting need for rapid operational adjustments to control concentrate grades thereby maximising the financial returns. An 'on-line' analyser system presented itself as a suitable alternative to the existing control method of smaller laboratory x-ray fluorescence analysers. On the system as installed at Rooiberg, two probes were fitted in each analysis zone, viz a density probe using high energy gamma radiation from a Cesium 127 source and a specific element absorption probe using low energy gamma radiation from a Americium 241 source. The signals as received from the probes are fed to a line receiver unit in the control room where a micro computer is doing the processing and prints out the information as required. Several advantages of this type of installation were gained at Rooiberg Tin Limited

  8. BROAD ABSORPTION LINE DISAPPEARANCE ON MULTI-YEAR TIMESCALES IN A LARGE QUASAR SAMPLE

    Energy Technology Data Exchange (ETDEWEB)

    Filiz Ak, N.; Brandt, W. N.; Schneider, D. P. [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Hall, P. B. [Department of Physics and Astronomy, York University, 4700 Keele St., Toronto, Ontario M3J 1P3 (Canada); Anderson, S. F.; Gibson, R. R. [Astronomy Department, University of Washington, Seattle, WA 98195 (United States); Lundgren, B. F. [Department of Physics, Yale University, New Haven, CT 06511 (United States); Myers, A. D. [Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071 (United States); Petitjean, P. [Institut d' Astrophysique de Paris, Universite Paris 6, F-75014, Paris (France); Ross, Nicholas P. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 92420 (United States); Shen Yue [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-51, Cambridge, MA 02138 (United States); York, D. G. [Department of Astronomy and Astrophysics, and Enrico Fermi Institute, University of Chicago, 5640 S. Ellis Ave., Chicago, IL 60637 (United States); Bizyaev, D.; Brinkmann, J.; Malanushenko, E.; Oravetz, D. J.; Pan, K.; Simmons, A. E. [Apache Point Observatory, P.O. Box 59, Sunspot, NM 88349-0059 (United States); Weaver, B. A., E-mail: nfilizak@astro.psu.edu [Center for Cosmology and Particle Physics, New York University, New York, NY 10003 (United States)

    2012-10-01

    We present 21 examples of C IV broad absorption line (BAL) trough disappearance in 19 quasars selected from systematic multi-epoch observations of 582 bright BAL quasars (1.9 < z < 4.5) by the Sloan Digital Sky Survey-I/II (SDSS-I/II) and SDSS-III. The observations span 1.1-3.9 yr rest-frame timescales, longer than have been sampled in many previous BAL variability studies. On these timescales, Almost-Equal-To 2.3% of C IV BAL troughs disappear and Almost-Equal-To 3.3% of BAL quasars show a disappearing trough. These observed frequencies suggest that many C IV BAL absorbers spend on average at most a century along our line of sight to their quasar. Ten of the 19 BAL quasars showing C IV BAL disappearance have apparently transformed from BAL to non-BAL quasars; these are the first reported examples of such transformations. The BAL troughs that disappear tend to be those with small-to-moderate equivalent widths, relatively shallow depths, and high outflow velocities. Other non-disappearing C IV BALs in those nine objects having multiple troughs tend to weaken when one of them disappears, indicating a connection between the disappearing and non-disappearing troughs, even for velocity separations as large as 10,000-15,000 km s{sup -1}. We discuss possible origins of this connection including disk-wind rotation and changes in shielding gas.

  9. Time Domain Astronomy with Fermi GBM in the Multi-messenger Era

    Science.gov (United States)

    Wilson-Hodge, Colleen A.; Fermi GBM team, GBM-LIGO team

    2018-01-01

    As the Multi-Messenger era begins with detections of gravitational waves with LIGO/Virgo and neutrinos with IceCube, the Fermi Gamma-ray Burst Monitor (GBM) provides context observations of gamma-ray transients between 8 keV and 40 MeV. Fermi GBM has a wide field of view, high uptime, and both in-orbit triggering and high time resolution continuous data enabling offline searches for weaker transients. GBM detects numerous gamma-ray bursts (GRBs), soft gamma-ray repeaters, X-ray bursters, solar flares and terrestrial gamma-ray flashes. Longer timescale transients, predominantly in our galaxy so far, are detected using the Earth occultation technique and epoch-folding for periodic sources. The GBM team has developed two ground-based searches to enhance detections of faint transients, especially short GRBs. The targeted search uses the time and location of an event detected with another instrument to coherently search the GBM data, increasing the sensitivity to a transient. The untargeted search agnostically searches the GBM data for all directions and times to find weaker transients. This search finds about 80 short GRBs per year, adding to the 40 per year triggered on-orbit. With its large field of view, high duty cycle and increasingly sophisticated detection methods, Fermi GBM is expected to have a major role in the Multi-Messenger era.

  10. Time-of-flight spectrometer for the measurement of gamma correlated neutron spectra

    International Nuclear Information System (INIS)

    Andryashin, A.V.; Devlein, B.V.; Lychagin, A.A.; Minko, Y.V.; Mironov, A.N.; Nesterenko, V.S.

    1986-01-01

    A time-of-flight spectrometer for the measurement of gamma correlated neutron spectra form (n,xnγ) reactions is described. The operation and the main parameters are discussed. The resolution in the neutron channel is 2.2 ns/m at the 150 keV neutron energy threshold. A simultaneous measurement of the time-of-flight and amplitude distributions makes it possible to study gamma correlated neutron spectra as well as the prompt gamma spectra in coincidence with selected energy neutrons. In order to test the spectrometer, measurements of the neutron spectrum in coincidence with the 846 keV gamma line of 56 Fe were carried out at an incident neutron energy of 14.1 MeV. (author). 3 figs., 6 refs

  11. Electron and positron contributions to the displacement per atom profile in bulk multi-walled carbon nanotube material irradiated with gamma rays; Aporte de electrones y positrones al perfil de desplazamientos atomicos en materiales masivos de nanotubos de carbono de paredes multiples irradiados con rayos gamma

    Energy Technology Data Exchange (ETDEWEB)

    Leyva Fabelo, Antonio; Pinnera Hernandez, Ibrahin; Leyva Pernia, Diana, E-mail: aleyva@ceaden.edu.cu [Centro de Aplicaciones Tecnologicas y Desarrollo Nuclear (CEADEN), La Habana (Cuba); others, and

    2013-07-01

    The electron and positron contributions to the effective atom displacement cross-section in multi-walled carbon nanotube bulk materials exposed to gamma rays were calculated. The physical properties and the displacement threshold energy value reported in literature for this material were taken into account. Then, using the mathematical simulation of photon and particle transport in matter, the electron and positron energy flux distributions within the irradiated object were also calculated. Finally, considering both results, the atom displacement damage profiles inside the analyzed bulk carbon nanotube material were determined. The individual contribution from each type of secondary particles generated by the photon interactions was specified. An increasing behavior of the displacement cross-sections for all the studied particles energy range was observed. The particles minimum kinetic energy values that make probabilistically possible the single and multiple atom displacement processes were determined. The positrons contribution importance to the total number of point defects generated during the interaction of gamma rays with the studied materials was confirmed.

  12. MoonBEAM: A Beyond Earth-Orbit Gamma-Ray Burst Detector for Gravitational-Wave Astronomy

    Science.gov (United States)

    Hui, C. M.; Briggs, M. S.; Goldstein, A. M.; Jenke, P. A.; Kocevski, D.; Wilson-Hodge, C. A.

    2018-01-01

    Moon Burst Energetics All-sky Monitor (MoonBEAM) is a CubeSat concept of deploying gamma-ray detectors in cislunar space to improve localization precision for gamma-ray bursts by utilizing the light travel time difference between different orbits. We present here a gamma-ray SmallSat concept in Earth-Moon L3 halo orbit that is capable of rapid response and provide a timing baseline for localization improvement when partnered with an Earth-orbit instrument. Such an instrument would probe the extreme processes in cosmic collision of compact objects and facilitate multi-messenger time-domain astronomy to explore the end of stellar life cycles and black hole formations.

  13. Search for Doppler-shifted gamma-ray emission from SS 433 using the SMM spectrometer

    International Nuclear Information System (INIS)

    Geldzahler, B.J.; Share, G.H.; Kinzer, R.L.; Magura, J.; Chupp, E.L.

    1989-01-01

    Data accumulated from 1980 to 1983 with the Gamma Ray Spectrometer aboard NASA's Solar Maximum Mission (SMM) satellite were searched for evidence of red and blue Doppler-shifted 1.37 MeV Mg-24 nuclear lines from SS 433. The SMM data base covers 270 days when SS 433 was in the field of view and includes periods of radio flaring and quiescence. No evidence was found for Doppler-shifted line emission in any of the spectra. The range of 3-sigma upper limits for individual 9 day integration periods was 0.0008-0.0023 photons/sq cm per sec for the blue beam, encompassing the reported about 1.5 MeV line, and 0.0008-0.002 photons/sq cm per sec for the red beam, encompassing the reported about 1.2 MeV line; the average 3-sigma upper limit in each beam for shifted about 1.37 MeV lines is 0.0015 photons/sq cm per sec for single 9 day integrations. The 3-sigma upper limit on 1.37 MeV gamma-ray emission over 23 9-day integration intervals for the red beam and 28 intervals for the blue beam is 0.0002 photons/sq cm per sec. These new limits from SMM can be reconciled with the HEAO 3 results only if SS 433 emits gamma radiation at or above the SMM sensitivity limit on rare occasions due to variable physical conditions in the system. 19 refs

  14. Search for Doppler-shifted gamma-ray emission from SS 433 using the SMM spectrometer

    Science.gov (United States)

    Geldzahler, B. J.; Share, G. H.; Kinzer, R. L.; Magura, J.; Chupp, E. L.

    1989-01-01

    Data accumulated from 1980 to 1983 with the Gamma Ray Spectrometer aboard NASA's Solar Maximum Mission (SMM) satellite were searched for evidence of red and blue Doppler-shifted 1.37 MeV Mg-24 nuclear lines from SS 433. The SMM data base covers 270 days when SS 433 was in the field of view and includes periods of radio flaring and quiescence. No evidence was found for Doppler-shifted line emission in any of the spectra. The range of 3-sigma upper limits for individual 9 day integration periods was 0.0008-0.0023 photons/sq cm per sec for the blue beam, encompassing the reported about 1.5 MeV line, and 0.0008-0.002 photons/sq cm per sec for the red beam, encompassing the reported about 1.2 MeV line; the average 3-sigma upper limit in each beam for shifted about 1.37 MeV lines is 0.0015 photons/sq cm per sec for single 9 day integrations. The 3-sigma upper limit on 1.37 MeV gamma-ray emission over 23 9-day integration intervals for the red beam and 28 intervals for the blue beam is 0.0002 photons/sq cm per sec. These new limits from SMM can be reconciled with the HEAO 3 results only if SS 433 emits gamma radiation at or above the SMM sensitivity limit on rare occasions due to variable physical conditions in the system.

  15. HCP to FCT + precipitate transformations in lamellar gamma-titanium aluminide alloys

    Science.gov (United States)

    Karadge, Mallikarjun Baburao

    Fully lamellar gamma-TiAl [alpha2(HCP) + gamma(FCT)] based alloys are potential structural materials for aerospace engine applications. Lamellar structure stabilization and additional strengthening mechanisms are major issues in the ongoing development of titanium aluminides due to the microstructural instability resulting from decomposition of the strengthening alpha 2 phase. This work addresses characterization of multi-component TiAl systems to identify the mechanism of lamellar structure refinement and assess the effects of light element additions (C and Si) on creep deformation behavior. Transmission electron microscopy studies directly confirmed for the first time that, fine lamellar structure is formed by the nucleation and growth of a large number of basal stacking faults on the 1/6 dislocations cross slipping repeatedly into and out of basal planes. This lamellar structure can be tailored by modifying jog heights through chemistry and thermal processing. alpha 2 → gamma transformation during heating (investigated by differential scanning calorimetry and X-ray diffraction) is a two step process involving the formation of a novel disordered FCC gamma' TiAl [with a(gamma') = c(gamma)] as an intermediate phase followed by ordering. Addition of carbon and silicon induced Ti2AlC H-type carbide precipitation inside the alpha2 lath and Ti 5(Al,Si)3 zeta-type silicide precipitation at the alpha 2/gamma interface. The H-carbides preserve alpha2/gamma type interfaces, while zeta-silicide precipitates restrict ledge growth and interfacial sliding enabling strong resistance to creep deformation.

  16. Skyshine spectra of gamma rays

    International Nuclear Information System (INIS)

    Swarup, Janardan

    1980-01-01

    A study of the spectra of gamma photons back-scattered in vertical direction by infinite air above ground (skyshine) is presented. The source for these measurements is a 650 Ci Cobalt-60 point-source and the skyshine spectra are reported for distances from 150 m to 325 m from the source, measured with a 5 cm x 5 cm NaI(Tl) detector collimated with collimators of 12 mm and 20 mm diameter and 5 cm length. These continuous spectra are unfolded with Gold's iterative technique. The photon-spectra so obtained have a distinct line at 72 keV due to multiply-scattered photons. This is an energy where photoelectric and Compton cross-sections for multiply-scattered photons balance each other. The intensity of the line(I) decreases exponentially with distance (d) from the source obeying a relation of the type I = Isub(o)esup(-μd) where μ is called as ''Multiply-Scatter Coefficient'', a constant of the medium which is air in these measurements. This relationship is explained in terms of a halo around the source comprising of multiply-scattered gamma photons, Isub(0) being the intensity of these scattered photons at the location of cobalt-source. A fraction called as ''Back-scattered Fraction'', the ratio of Isub(0) to the number of original photons from the cobalt-source entering the infinite air, is also calculated. It is shown that with a properly calibrated detector system, this fraction can be used to determine the strength of a large gamma source, viz. a nuclear explosion in air, and for mineral prospecting. These conclusions are general and can be applied to any other infinite medium. Some forward-scatter (transmission) spectra of cobalt-60 source through 10 cm of Pb and 2.5 cm of Al are also reported. (auth.)

  17. Verification of Gamma-ray Sensitivity for BF3 Neutron Detection System

    International Nuclear Information System (INIS)

    Choi, Yu Sun; Cho, Jin Bok; Lyou, Seok Jean

    2016-01-01

    The BF3(Boron Tri-Fluorides) gas filled neutron detector(hereafter BF3 Detector) is commonly used for nuclear reactor’s startup channel due to its relatively high neutron efficiency and good discrimination against gamma-ray backgrounds. In order to measure how much this gamma-ray will affect on BF3 neutron detector performance in view of gamma noise discrimination, Multi-Channel Analyzer(MCA) is utilized for spectrum based signal analysis. The pre-test of BF3 Detector should be performed in an area where the ionization does not exceed 2.5 micro Gy/Hr(Ref.1). In this paper, the discrimination level (Voltage Unit) is verified by experimentally measurement if that discrimination level is acceptable within the criteria or not before installation. The maximum discrimination level, so called LLD, is determined by experimentally measurement. This BF3 Detector (LND20372) is insensitive under 540 micro Gy/Hr of gamma ray and 0.3V of LLD could cut off a background and gamma induced signal in a laboratory. MCA could be a convenient tool for spectrum analysis of signals that induced from gamma ray and a time saving tool rather than oscilloscope investigation due to its function to integrate all input signals at a sudden duration

  18. Effect of single and combined treatment with gamma rays and some chemical mutagens in rice

    International Nuclear Information System (INIS)

    Lyong Van Hin; Mekhandzhiev, A.; Murzova, P.; Chilikov, I.

    1991-01-01

    Dry rice seeds of 3 cvs and 2 lines have been irradiated (Co 60 , 10 krad) and treated with 0.0012% sodium azide (NaN 3 ) and 0.2% ethylmethanesulfonate (EMS) in definite combinations. It is found that chlorophyll mutations are less frequent after single gamma irradiation. Sodium azide produces a higher percentage of mutations than EMS. Highest mutation frequency has been observed following combined treatment with gamma rays and chemical mutagens. The combined treatment has resulted in a considerably higher mutation effect than the theoretically expected one in the lines Nora and Mega, and in cv. Krasnodarski 424. Highest mutation spectrum has been found in cv. Krasnodarski 424 and in Nora line following combined treatment. 1 tab., 5 figs., 20 refs

  19. Multi-step lining-up correction of the CLIC trajectory

    CERN Document Server

    D'Amico, T E

    1999-01-01

    In the CLIC main linac it is very important to minimise the trajectory excursion and consequently the emittance dilution in order to obtain the required luminosity. Several algorithms have been proposed and lately the ballistic method has proved to be very effective. The trajectory correction method described hereafter retains the main advantages of the latter while adding some interesting features. It is based on the separation of the unknown variables like the quadrupole misalignments, the offset and slope of the injection straight line and the misalignments of the beam position monitors (BPM). This is achieved by referring the trajectory relatively to the injection line and not to the average pre-alignment line and by using two trajectories each corresponding to slightly different quadrupole strengths. A reference straight line is then derived onto which the beam is bent by a kick obtained by moving the first quadrupole. The other quadrupoles are then aligned on that line. The quality of the correction dep...

  20. Manufacturing lines under surplus-based control : multiple products and bounded buffers

    NARCIS (Netherlands)

    Starkov, K.; Pogromskiy, A.Y.; Adan, I.J.B.F.

    2015-01-01

    Challenged by the scheduling complexity for production flow processes in industrial facilities, we study the performance of multi-product producing lines. We analyse the performance of multi-product lines that consist a number of machines and bounded buffers with preselected base stock levels. It is

  1. Formation properties from high resolution neutron activation gamma-ray spectra

    International Nuclear Information System (INIS)

    Mellor, D.W.; Underwood, M.C.

    1985-01-01

    A neutron activation logging tool has been developed comprising a Five Curie /sup 241/ Am-Be neutron source and a large n-type hyper-pure germanium gamma-ray detector. The tool maintains a constant temperature cryogenic environment for periods in excess of twenty hours. No liquid nitrogen or other consumable material is used in the operating or recharging stages. A large calibration tank in simulated well-bore geometry has been constructed with sand bodies saturated with oil and low salinity water (14,000 ppm NaCl). In the water zone prompt neutron capture gamma-rays from silicon, hydrogen and chlorine were prominent; gamma-rays from inelastic scattering on oxygen and silicon were detected. No gamma-rays arising from inelastic scattering on carbon were detected. These data have been interpreted to yield the porosity, fluid saturations, salinity and matrix composition. In the oil zone, gamma-rays arising from inelastic scattering on oxygen, silicon and carbon were detected. The intensity of the carbon line was very poor, and inadequate for quantitative purposes

  2. Capture Gamma-Ray Libraries for Nuclear Applications

    International Nuclear Information System (INIS)

    Sleaford, B.W.; Firestone, Richard B.; Summers, N.; Escher, J.; Hurst, A.; Krticka, M.; Basunia, S.; Molnar, G.; Belgya, T.; Revay, Z.; Choi, H.D.

    2010-01-01

    The neutron capture reaction is useful in identifying and analyzing the gamma-ray spectrum from an unknown assembly as it gives unambiguous information on its composition. This can be done passively or actively where an external neutron source is used to probe an unknown assembly. There are known capture gamma-ray data gaps in the ENDF libraries used by transport codes for various nuclear applications. The Evaluated Gamma-ray Activation file (EGAF) is a new thermal neutron capture database of discrete line spectra and cross sections for over 260 isotopes that was developed as part of an IAEA Coordinated Research Project. EGAF has been used to improve the capture gamma production in ENDF libraries. For medium to heavy nuclei the quasi continuum contribution to the gamma cascades is not experimentally resolved. The continuum contains up to 90% of all the decay energy an is modeled here with the statistical nuclear structure code DICEBOX. This code also provides a consistency check of the level scheme nuclear structure evaluation. The calculated continuum is of sufficient accuracy to include in the ENDF libraries. This analysis also determines new total thermal capture cross sections and provides an improved RIPL database. For higher energy neutron capture there is less experimental data available making benchmarking of the modeling codes more difficult. We use CASINO, a version of DICEBOX that is modified for this purpose. This can be used to simulate the neutron capture at incident neutron energies up to 20 MeV to improve the gamma-ray spectrum in neutron data libraries used for transport modelling of unknown assemblies.

  3. Peroxisome proliferator-activated receptor gamma coactivator-1 alpha acts as a tumor suppressor in hepatocellular carcinoma.

    Science.gov (United States)

    Liu, Rui; Zhang, Haiyang; Zhang, Yan; Li, Shuang; Wang, Xinyi; Wang, Xia; Wang, Cheng; Liu, Bin; Zen, Ke; Zhang, Chen-Yu; Zhang, Chunni; Ba, Yi

    2017-04-01

    Peroxisome proliferator-activated receptor gamma coactivator-1 alpha plays a crucial role in regulating the biosynthesis of mitochondria, which is closely linked to the energy metabolism in various tumors. This study investigated the regulatory role of peroxisome proliferator-activated receptor gamma coactivator-1 alpha in the pathogenesis of hepatocellular carcinoma. In this study, the changes of peroxisome proliferator-activated receptor gamma coactivator-1 alpha messenger RNA levels between normal human liver and hepatocellular carcinoma tissue were examined by quantitative reverse transcription polymerase chain reaction. Knockdown of peroxisome proliferator-activated receptor gamma coactivator-1 alpha was conducted by RNA interference in the human liver cell line L02, while overexpression of peroxisome proliferator-activated receptor gamma coactivator-1 alpha was conducted by adenovirus encoding peroxisome proliferator-activated receptor gamma coactivator-1 alpha complementary DNA in the human hepatocarcinoma cell line HepG2. Cellular morphological changes were observed via optical and electron microscopy. Cellular apoptosis was determined by Hoechst 33258 staining. In addition, the expression levels of 21,400 genes in tissues and cells were detected by microarray. It was shown that peroxisome proliferator-activated receptor gamma coactivator-1 alpha expression was significantly downregulated in hepatocellular carcinoma compared with normal liver tissues. After knockdown of peroxisome proliferator-activated receptor gamma coactivator-1 alpha expression in L02 cells, cells reverted to immature and dedifferentiated morphology exhibiting cancerous tendency. Apoptosis occurred in the HepG2 cells after transfection by adenovirus encoding peroxisome proliferator-activated receptor gamma coactivator-1 alpha. Microarray analysis showed consistent results. The results suggest that peroxisome proliferator-activated receptor gamma coactivator-1 alpha acts as a tumor

  4. Further development of a cosmic veto gamma-spectrometer

    International Nuclear Information System (INIS)

    Burnett, J.L.; Davies, A.V.; McLarty, J.L.

    2013-01-01

    The Comprehensive Nuclear-Test-Ban Treaty (CTBT) is supported by a network of certified laboratories that perform high-resolution gamma-spectrometry on global air filter samples for the identification of 85 radionuclides. At the UK CTBT Radionuclide Laboratory (GBL15), a novel cosmic veto gamma-spectrometer has been developed to improve the sensitivity of measurements for treaty compliance. The system consists of plastic scintillation plates operated in time-stamp mode to detect coincident cosmic-ray interactions within an HPGe gamma-spectrometer. This provides a mean background reduction of 75.2 % with MDA improvements of 45.6 %. The CTBT requirement for a 140 Ba MDA is achievable after 1.5 days counting compared to 5-7 days using conventional systems. The system does not require dedicated coincidence electronics, and remains easily configurable with dual acquisition of unsuppressed and suppressed spectra. Performance has been significantly improved by complete processing of the cosmic-ray spectrum (0-25 MeV) combined with the Canberra Lynx TM multi-channel analyser. The improved sensitivity has been demonstrated for a CTBT air filter sample collected after the Fukushima incident. (author)

  5. Time evolution of gamma rays from supernova remnants

    Science.gov (United States)

    Gaggero, Daniele; Zandanel, Fabio; Cristofari, Pierre; Gabici, Stefano

    2018-04-01

    We present a systematic phenomenological study focused on the time evolution of the non-thermal radiation - from radio waves to gamma rays - emitted by typical supernova remnants via hadronic and leptonic mechanisms, for two classes of progenitors: thermonuclear and core-collapse. To this aim, we develop a numerical tool designed to model the evolution of the cosmic ray spectrum inside a supernova remnant, and compute the associated multi-wavelength emission. We demonstrate the potential of this tool in the context of future population studies based on large collection of high-energy gamma-ray data. We discuss and explore the relevant parameter space involved in the problem, and focus in particular on their impact on the maximum energy of accelerated particles, in order to study the effectiveness and duration of the PeVatron phase. We outline the crucial role of the ambient medium through which the shock propagates during the remnant evolution. In particular, we point out the role of dense clumps in creating a significant hardening in the hadronic gamma-ray spectrum.

  6. Heterogeneity within populations of recombinant Chinese hamster ovary cells expressing human interferon-gamma.

    Science.gov (United States)

    Coppen, S R; Newsam, R; Bull, A T; Baines, A J

    1995-04-20

    The Chinese hamster ovary (CHO) cell line has great commercial importance in the production of recombinant human proteins, especially those for therapeutic use. Much attention has been paid to CHO cell population physiology in order to define factors affecting product fidelity and yield. Such studies have revealed that recombinant proteins, including human interferon-gamma (IFN-gamma), can be heterogeneous both in glycosylation and in proteolytic processing. The type of heterogeneity observed depends on the growth physiology of the cell population, although the relationship between them is complex. In this article we report results of a cytological study of the CHO320 line which expresses recombinant human IFN-gamma. When grown in suspension culture, this cell line exhibited three types of heterogeneity: (1) heterogeneity of the production of IFN-gamma within the cell population, (2) heterogeneity of the number of nuclei and mitotic spindles in dividing cells, and (3) heterogeneity of cellular environment. The last of these arises from cell aggregates which form in suspension culture: Some cells are exposed to the culture medium; others are fully enclosed within the mass with little or no direct access to the medium. Thus, live cells producing IFN-gamma are heterogeneous in their environment, with variable access to O(2) and nutrients. Within the aggregates, it appears that live cells proliferate on a dead cell mass. The layer of live cells can be several cells deep. Specific cell-cell attachments are observed between the living cells in these aggregates. Two proteins, known to be required for the formation of certain types of intercellular junctions, spectrin and vinculin, have been localized to the regions of cell-cell contact. The aggregation of the cells appears to be an active process requiring protein synthesis. (c) 1995 John Wiley & Sons, Inc.

  7. The evaluation of radiation level and dose of workers in Guangzhou metro line 1

    International Nuclear Information System (INIS)

    Zhang Lin; Hu Canyun; Meng Xiaolian; He Zhan

    2006-01-01

    Objective: To find out the level of radiation and effective dose of workers in Guangzhou Metro line 1. Methods: In metro stations, external Gamma-ray exposure rates were obtained by FD-71A radiance measurer, 222 Rn and 220 Rn concentrations were obtained by using Rn-Tn solid state nuclear track detectors developed by The National Institute for Radiological Protection and Nuclear Safety, Chinese Centre for Disease Control. The annual Effective dose from Gamma, 222 Rn and 220 Rn were calculated. Results: The external Gamma-ray exposure average rate is 17.74 x 10 -8 Gy/h. The average concentration of 222 Rn is 59.8 Bq/m 3 . The average concentration of 220 Rn is 32.1 Bq/m 3 . The total annual effective dose from Gamma, 222 Rn and 220 Rn is 2.878 mSv/a. Conclusion: In the stations of Guangzhou in metro line 1, no more effective radiation dose to the workers has measured. (authors)

  8. Determination of gamma radiation lethal dose (LD50) and resveratrol cytotoxicity level in tumor cells line

    International Nuclear Information System (INIS)

    Magalhaes, Vanessa D.; Rogero, Sizue O.; Rogero, Jose R.; Cruz, Aurea S.

    2011-01-01

    Cancer is a disease with high incidence and it is considered a worldwide public health problem. Resveratrol is a polyphenol occurring naturally in a wide variety of plants according to response of ultraviolet radiation (UV) exposition or according to mechanical stress resulting of pathogens or chemical and physical agents. This polyphenol possesses a pharmacological activity of carcinogenesis inhibition in multiple levels. It also protects cells by scavenging the free radicals which are considered toxic products. These free radicals are formed of natural process of cell aging and also by incidence of ionizing radiation in the organism. Thus, resveratrol is considered as a cell radioprotector. On the other hand, in some elevated concentrations resveratrol may be considered as a radiosensitizing. The aim of this work was the determination of radiation lethal dose (LD 50 ) and also verifies the cytotoxicity level of resveratrol in tumor cells line: muco epidermoid pulmonary carcinoma cells (NCI-H292) and rhabdomyosarcoma cells (RD). The cytotoxicity test was performed by neutral red uptake assay. The results of resveratrol IC 50% in NCI-H292 cells was 192μM and in RD cells was 128μM; and RD cells gamma radiation LD 50 was 435Gy. (author)

  9. Improvement and Validation of an Aerosol Deposition Model in the GAMMA-FP, a Fission Product Analysis Module for VHTRs

    International Nuclear Information System (INIS)

    Yoon, Churl; Lim, Hong Sik

    2013-01-01

    GAMMA-FP (GAs Multicomponent Mixture Analysis-Fission Products module), consists of gaseous and aerosol fission product analysis modules. The aerosol FP module adopts a multi-component and multi-sectional aerosol analysis model that has been developed based on the MAEROS model. For the first work of FP module development, the MAEROS model has been implemented and examined against some analytic solutions and experimental data by Yoo et al. An aerosol transport model was developed and implemented in the GAMMA-FP code, and verified. In this study, the aerosol deposition model in the GAMMA-FP code was improved by adopting recent achievements, and was validated against an experimental data available. The aerosol deposition model in the GAMMA-FP code has been improved and successfully validated against the STORM SR-11 deposition test. The simulation with the improved deposition model predicted the matched results with the experimental data well. For future studies, the aerosol deposition model by flow irregularities will be implemented and validated against the TRANSAT bend effect test

  10. Improvement and Validation of an Aerosol Deposition Model in the GAMMA-FP, a Fission Product Analysis Module for VHTRs

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Churl; Lim, Hong Sik [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    GAMMA-FP (GAs Multicomponent Mixture Analysis-Fission Products module), consists of gaseous and aerosol fission product analysis modules. The aerosol FP module adopts a multi-component and multi-sectional aerosol analysis model that has been developed based on the MAEROS model. For the first work of FP module development, the MAEROS model has been implemented and examined against some analytic solutions and experimental data by Yoo et al. An aerosol transport model was developed and implemented in the GAMMA-FP code, and verified. In this study, the aerosol deposition model in the GAMMA-FP code was improved by adopting recent achievements, and was validated against an experimental data available. The aerosol deposition model in the GAMMA-FP code has been improved and successfully validated against the STORM SR-11 deposition test. The simulation with the improved deposition model predicted the matched results with the experimental data well. For future studies, the aerosol deposition model by flow irregularities will be implemented and validated against the TRANSAT bend effect test.

  11. Gamma irradiation facilities for radiation tolerance assessment of components and systems at SCK.CEN

    International Nuclear Information System (INIS)

    Coenen, S.; Decreton, M.

    1999-01-01

    This paper presents the different gamma irradiation facilities available at SCK-CEN (Mol, Belgium). With gamma dose rates ranging from 1 Gy/h up to 50 kGy/h, extensive environmental control and on-line instrumentation possibilities, they offer ideal test environments for the radiation tolerance assessment of components and systems for many applications where radiation tolerance is a concern. (authors)

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

    Science.gov (United States)

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

    2014-01-01

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

  13. Automatic classification of gammas-gamma coincidence matrices

    International Nuclear Information System (INIS)

    Los Arcos Merino, J. M.; Gonzalez, J. A.

    1978-01-01

    The information obtained during a coincidence experiment, recorded on magnetic tape by a MULTI-8 minicomputer, is transferred to a new tape in 36 bit words, using the program LEC0M8. The classification in two dimensional matrix form is carried out off-line, on a magnetic disk file, by the program CLAFI. On finishing classification one obtains a copy of the coincidence matrix on the second magnetic tape. Both programs are written to be processed in that order with the UNIVAC 1106 computer of J.E.N. (Author) 4 refs

  14. Automatic classification of gamma-gamma coincidence matrices

    International Nuclear Information System (INIS)

    Los Arcos Merino, J.M.; Gonzalez Gonzalez, J.A.

    1978-01-01

    The information obtained during a coincidence experiment, recorded on magnetic tape by a Multi-8 minicomputer, is transferred to a new tape in 36 bit words, using the program Lecom8. The classification in two dimensional matrix form is carried out off-line, on a magnetic disk file, by the program Clafi. On finishing classification one obtains a copy of the coincidence matrix on the second magnetic tape. Both programs are written to be processed in that order with the Univac 1106 computer of J.E.N. (author)

  15. Gamma spectra pictures using a digital plotter. Program MONO

    International Nuclear Information System (INIS)

    Los Arcos Merino, J.M.

    1978-01-01

    The program MONO has been written for a CALCOMP-936 digital plotter operating off- -line with a UMI VAC 1106 computer, to obtain graphic representations of single gamma spectra stored on magnetic tape. It allows to plot the whole spectrum or only a part, as well as to draw a given spectrum on the same or different picture than the previous one. Ten representation scales are available and at up nine comment lines can be written in a graphic. (Author) 4 refs

  16. On Gamma Ray Instrument On-Board Data Processing Real-Time Computational Algorithm for Cosmic Ray Rejection

    Science.gov (United States)

    Kizhner, Semion; Hunter, Stanley D.; Hanu, Andrei R.; Sheets, Teresa B.

    2016-01-01

    Richard O. Duda and Peter E. Hart of Stanford Research Institute in [1] described the recurring problem in computer image processing as the detection of straight lines in digitized images. The problem is to detect the presence of groups of collinear or almost collinear figure points. It is clear that the problem can be solved to any desired degree of accuracy by testing the lines formed by all pairs of points. However, the computation required for n=NxM points image is approximately proportional to n2 or O(n2), becoming prohibitive for large images or when data processing cadence time is in milliseconds. Rosenfeld in [2] described an ingenious method due to Hough [3] for replacing the original problem of finding collinear points by a mathematically equivalent problem of finding concurrent lines. This method involves transforming each of the figure points into a straight line in a parameter space. Hough chose to use the familiar slope-intercept parameters, and thus his parameter space was the two-dimensional slope-intercept plane. A parallel Hough transform running on multi-core processors was elaborated in [4]. There are many other proposed methods of solving a similar problem, such as sampling-up-the-ramp algorithm (SUTR) [5] and algorithms involving artificial swarm intelligence techniques [6]. However, all state-of-the-art algorithms lack in real time performance. Namely, they are slow for large images that require performance cadence of a few dozens of milliseconds (50ms). This problem arises in spaceflight applications such as near real-time analysis of gamma ray measurements contaminated by overwhelming amount of traces of cosmic rays (CR). Future spaceflight instruments such as the Advanced Energetic Pair Telescope instrument (AdEPT) [7-9] for cosmos gamma ray survey employ large detector readout planes registering multitudes of cosmic ray interference events and sparse science gamma ray event traces' projections. The AdEPT science of interest is in the

  17. Interpretation of the radioactive background observed in the OSO-7 gamma ray monitor

    International Nuclear Information System (INIS)

    Dyer, C.S.

    1975-01-01

    Application of a spallation activation calculation to the OSO-7 gamma-ray monitor background shows that major line features and about 30% of the continuum can be understood as activation of the central detector crystal by trapped protons. Weaker line features arise from activation of materials unshielded by the anticoincidence cup, while the remaining continuum and annihilation line would seem to come largely continuum and annihilation line would seem to come largely from electron-photon cascades originating in the spacecraft. (orig.) [de

  18. Determination of organic-matter content of Appalachian Devonian shales from gamma-ray logs

    International Nuclear Information System (INIS)

    Schmoker, J.W.

    1981-01-01

    The organic-matter content of the Devonian shale of the Appalachian basin is important for assessing the natural-gas resources of these rocks, and patterns of organic-matter distribution convey information on sedimentary processes and depositional environment. In most of the western part of the Appalachian basin the organic-matter content of the Devonian shale can be estimated from gamma-ray wire-line logs using the equation: phi 0 = (γ/sub B/ - γ)/1.378A, where phi 0 is the organic-matter content of the shale (fractional volume), γ the gamma-ray intensity (API units), γ/sub B/ the gamma-ray intensity if no organic matter is present (API units), and A the slope of the crossplot of gamma-ray intensity and formation density (API units/(g/cm 3 )). Organic-matter contents estimated using this equation are compared with organic-matter contents determined from direct laboratory analyses of organic carbon for 74 intervals of varying thickness from 12 widely separated wells. The organic-matter content of these intervals ranges from near zero to about 20% by volume. The gamma-ray intensity of the Cleveland Member of the Ohio Shale and the lower part of the Olentangy Shale is anomalously low compared to other Devonian shales of similar richness, so that organic-matter content computed for each of these units from gamma-ray logs is likely to be too low. Wire-line methods for estimating organic-matter content have the advantages of economy, readily available sources of data, and continuous sampling of the vertically heterogenous shale section. The gamma-ray log, in particular, is commonly run in the Devonian shale, its response characteristics are well known, and the cumulative pool of gamma-ray logs forms a large and geographically broad data base. The quantitative computation of organic-matter content from gamma-ray logs should be of practical value in studies of the Appalachian Devonian shale. 16 figures

  19. Evaluation of gamma irradiation of teas

    Energy Technology Data Exchange (ETDEWEB)

    Gerolis, Luanai G.L.; Lameiras, Fernando S.; Menezes, Maria A.B.C.; Leal, Alexandre S., E-mail: luanaigraz@yahoo.com.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Krambrock, Klaus, E-mail: klaus@fisica.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Fisica. Lab. de Ressonancia Paramagnetica Eletronica

    2013-07-01

    There is a growing interest in the determination of non-essential traces elements in agroindustrial products. The continuous ingestion and accumulation in the organism of such elements, that may be toxic, can cause hazards to the human health in the long term. Reliable analytical techniques are necessary to monitor such products, including teas. In this work, the neutron activation technique is being employed to determine the trace elements in teas, due to its high sensibility and the possibility to perform a multi-elementary analysis. The gamma irradiation of teas is also being studied, because the shelf life can be extended and no chemical product is added to the teas. There is a concern related to the formation of free radicals in the teas, which is being accessed with electronic paramagnetic resonance. The results of the gamma irradiation up to 20 kGy of Camelia sinensis, Ilex paraguariensis, and Matricaria recutita are presented. (author)

  20. Evaluation of gamma irradiation of teas

    International Nuclear Information System (INIS)

    Gerolis, Luanai G.L.; Lameiras, Fernando S.; Menezes, Maria A.B.C.; Leal, Alexandre S.; Krambrock, Klaus

    2013-01-01

    There is a growing interest in the determination of non-essential traces elements in agroindustrial products. The continuous ingestion and accumulation in the organism of such elements, that may be toxic, can cause hazards to the human health in the long term. Reliable analytical techniques are necessary to monitor such products, including teas. In this work, the neutron activation technique is being employed to determine the trace elements in teas, due to its high sensibility and the possibility to perform a multi-elementary analysis. The gamma irradiation of teas is also being studied, because the shelf life can be extended and no chemical product is added to the teas. There is a concern related to the formation of free radicals in the teas, which is being accessed with electronic paramagnetic resonance. The results of the gamma irradiation up to 20 kGy of Camelia sinensis, Ilex paraguariensis, and Matricaria recutita are presented. (author)

  1. Spectroscopy high above the yrast line in rare earth nuclei

    International Nuclear Information System (INIS)

    Ramsoey, T.

    1990-01-01

    The particle-gamma coincidence technique presented in this work has proved to be a powerful tool in the study of nuclear structure. The most important feature is the ability to select well-defined excitation regions of entry states in a narrow spin window. The author has focused on the gamma-decay of low- lying descrete states and the gross structure properties in the region far above the yrast line. 6 refs., 5 figs

  2. Irradiated KHYG-1 retains cytotoxicity: potential for adoptive immunotherapy with a natural killer cell line.

    Science.gov (United States)

    Suck, G; Branch, D R; Keating, A

    2006-05-01

    To evaluate gamma-irradiation on KHYG-1, a highly cytotoxic natural killer (NK) cell line and potential candidate for cancer immunotherapy. The NK cell line KHYG-1 was irradiated at 1 gray (Gy) to 50 Gy with gamma-irradiation, and evaluated for cell proliferation, cell survival, and cytotoxicity against tumor targets. We showed that a dose of at least 10 Gy was sufficient to inhibit proliferation of KHYG-1 within the first day but not its cytolytic activity. While 50 Gy had an apoptotic effect in the first hours after irradiation, the killing of K562 and HL60 targets was not different from non-irradiated cells but was reduced for the Ph + myeloid leukemia lines, EM-2 and EM-3. gamma-irradiation (at least 10 Gy) of KHYG-1 inhibits cell proliferation but does not diminish its enhanced cytolytic activity against several tumor targets. This study suggests that KHYG-1 may be a feasible immunotherapeutic agent in the treatment of cancers.

  3. MULTI-WAVELENGTH OBSERVATIONS OF THE FLARING GAMMA-RAY BLAZAR 3C 66A IN 2008 OCTOBER

    International Nuclear Information System (INIS)

    Abdo, A. A.; Ackermann, M.; Ajello, M.; Bechtol, K.; Berenji, B.; Blandford, R. D.; Borgland, A. W.; Bouvier, A.; Buehler, R.; Baldini, L.; Bellazzini, R.; Bregeon, J.; Brez, A.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Buson, S.; Bonamente, E.; Brigida, M.; Bruel, P.

    2011-01-01

    The BL Lacertae object 3C 66A was detected in a flaring state by the Fermi Large Area Telescope (LAT) and VERITAS in 2008 October. In addition to these gamma-ray observations, F-GAMMA, GASP-WEBT, PAIRITEL, MDM, ATOM, Swift, and Chandra provided radio to X-ray coverage. The available light curves show variability and, in particular, correlated flares are observed in the optical and Fermi-LAT gamma-ray band. The resulting spectral energy distribution can be well fitted using standard leptonic models with and without an external radiation field for inverse Compton scattering. It is found, however, that only the model with an external radiation field can accommodate the intra-night variability observed at optical wavelengths.

  4. Gamma irradiation on canola seeds affects herbivore-plant and host-parasitoid interactions

    International Nuclear Information System (INIS)

    Akandeh, M.; Kocheili, F.; Rasekh, A.; Soufbaf, M.

    2017-01-01

    As an agricultural modernization, gamma irradiation is an important method for enhancing crop yield and quality. Nevertheless, its use can alter other plant traits such as nutrition and resistance to different biotic/abiotic stresses that consequently affect plant-insect interactions. A tritrophic system was utilized based on two canola mutant lines produced through gamma irradiation (RGS 8-1 and Talaye 8-3). Plutella xylostella (L.), as a worldwide pest of Brassicaceae and Cotesia vestalis (Holiday) as a key biocontrol agent of P. xylostella were examined for the potential indirect effects of canola seed irradiation on the experimental insects' performance when acting on the respective mutant lines. This study showed that physical mutation did not affect plant nitrogen and herbivore-damaged total phenolics; however, phenolic compounds showed greater concentration in damaged leaves than undamaged leaves of both mutant and control plants. The relative growth rate and pupal weight of P. xylostella reared on RGS 8-1 were significantly higher than those reared on the control RGS. There was no significant difference by performance parameters of the parasitoid, C. vestalis, including total pre-oviposition period, adult longevity, adult fresh body weight of males and females, pupal weight, forewing area, and total longevity of both sexes on tested canola cultivars in comparison with their mutant lines. Life table parameters of C. vestalis on mutant lines of both cultivars, RGS and Talaye, were not significantly different from their control treatments. Comprehensive studies should be conducted to find out the mechanisms under which gamma rays affect plant-insect interactions. (author)

  5. Gamma irradiation on canola seeds affects herbivore-plant and host-parasitoid interactions

    Energy Technology Data Exchange (ETDEWEB)

    Akandeh, M.; Kocheili, F.; Rasekh, A. [Dept. of Entomology, Shahid Chamran Univ of Ahvaz (Iran, Islamic Republic of); Soufbaf, M., E-mail: msoufbaf@nrcam.org [Agricultural, Medical and Industrial Research School, Karaj (Iran, Islamic Republic of)

    2017-06-15

    As an agricultural modernization, gamma irradiation is an important method for enhancing crop yield and quality. Nevertheless, its use can alter other plant traits such as nutrition and resistance to different biotic/abiotic stresses that consequently affect plant-insect interactions. A tritrophic system was utilized based on two canola mutant lines produced through gamma irradiation (RGS 8-1 and Talaye 8-3). Plutella xylostella (L.), as a worldwide pest of Brassicaceae and Cotesia vestalis (Holiday) as a key biocontrol agent of P. xylostella were examined for the potential indirect effects of canola seed irradiation on the experimental insects' performance when acting on the respective mutant lines. This study showed that physical mutation did not affect plant nitrogen and herbivore-damaged total phenolics; however, phenolic compounds showed greater concentration in damaged leaves than undamaged leaves of both mutant and control plants. The relative growth rate and pupal weight of P. xylostella reared on RGS 8-1 were significantly higher than those reared on the control RGS. There was no significant difference by performance parameters of the parasitoid, C. vestalis, including total pre-oviposition period, adult longevity, adult fresh body weight of males and females, pupal weight, forewing area, and total longevity of both sexes on tested canola cultivars in comparison with their mutant lines. Life table parameters of C. vestalis on mutant lines of both cultivars, RGS and Talaye, were not significantly different from their control treatments. Comprehensive studies should be conducted to find out the mechanisms under which gamma rays affect plant-insect interactions. (author)

  6. Study on the Effects of Sample Density on Gamma Spectrometry System Measurement Efficiency at Radiochemistry and Environment Laboratory

    International Nuclear Information System (INIS)

    Wo, Y.M.; Dainee Nor Fardzila Ahmad Tugi; Khairul Nizam Razali

    2015-01-01

    The effects of sample density on the measurement efficiency of the gamma spectrometry system were studied by using four sets multi nuclide standard sources of various densities between 0.3 - 1.4 g/ ml. The study was conducted on seven unit 25 % coaxial HPGe detector gamma spectrometry systems in Radiochemistry and Environment Laboratory (RAS). Difference on efficiency against gamma emitting radionuclides energy and measurement systems were compared and discussed. Correction factor for self absorption caused by difference in sample matrix density of the gamma systems were estimated. The correction factors are to be used in quantification of radionuclides concentration in various densities of service and research samples in RAS. (author)

  7. Application of the similitude principle to gamma-gamma density measurements; Application du principe de similitude a la mesure gamma-gamma de densite

    Energy Technology Data Exchange (ETDEWEB)

    Czubek, J A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires. Departement d' Electronique Generale, Service d' Electronique Industrielle; Institut de Recherches Nucleaires, Dep. VI, Cracow (Poland)

    1966-07-01

    The work presented here deals with the problem of the application of the similitude principle to rock density measurements by the gamma-gamma method. A formula is presented which makes it possible to transform results of gamma-gamma measurements carried out on models in order to make them suitable for comparison with results obtained under actual field conditions. Both the space coordinates and the densities are transformed. This transformation makes it possible to obtain a calibration curve as a function of the density for a gamma-gamma probe using only a single model of given density. The influence has also been studied of the chemical composition on the results obtained from gamma-gamma measurements. A method has been developed for estimating the equivalent Z parameter of the medium; the possibility of completely eliminating the influence of the chemical composition of the medium on the measurement results has been studied. (author) [French] L'etude presentee ci-dessous traite le probleme de l'application du principe de similitude aux mesures de densite des roches par la methode gamma-gamma. Nous indiquons une formule qui permet de transformer les resultats des mesures gamma-gamma effectuees sur les modeles pour les comparer aux resultats obtenus dans les conditions reelles sur le terrain. On transforme les coordonnees spatiales ainsi que les densites. Cette transformation donne la possibilite d'obtenir une courbe d'etalonnage (en fonction de la densite) pour une sonde gamma-gamma en utilisant un seul modele de densite donnee. On a etudie aussi l'influence de la composition chimique sur les resultats obtenus des mesures gamma-gamma. On a etabli une methode d'estimation du parametre Z equivalent du milieu, ainsi que la possibilite d'eliminer completement l'influence de la composition chimique du milieu sur les resultats des mesures de densite. (auteur)

  8. Enhanced release of bone morphogenetic proteins from demineralized bone matrix by gamma irradiation

    International Nuclear Information System (INIS)

    Sung, Nak-Yun; Choi, Jong-il

    2015-01-01

    Gamma irradiation is a useful method for sterilizing demineralized bone matrix (DBM), but its effect on the osteoinductivity of DBM is still controversial. In this study, the osteoinductive activity of gamma-irradiated DBM was examined using a mouse myoblastic cell line (C2C12). DBM was extracted from adult bovine bone and was irradiated at a dose of 25 kGy using a 60 cobalt gamma-irradiator. Cell proliferation with DBM was not affected by gamma-irradiation, but alkaline phosphatase and osteocalcin productions were significantly increased in C2C12 cell groups treated with gamma-irradiated DBM. It was reasoned that bone morphogenetic proteins were more efficiently released from gamma-irradiated DBM than from the non-irradiated control. This result suggests the effectiveness of radiation sterilization of bone implants - Highlights: • Demineralized bone matrix (DBM) was gamma-irradiated for sterilization. • Irradiated DBM had higher alkaline phosphatase and osteocalcin production. • It was reasoned the more released bone morphogenetic proteins by irradiation. • This result supports the application of radiation sterilization for bone implants

  9. Failure to synthesize the CD3-gamma chain. Consequences for T cell antigen receptor assembly, processing, and expression

    DEFF Research Database (Denmark)

    Geisler, C

    1992-01-01

    surface expression of the Ti/CD3 complex. Transfection of the wild-type CD3-gamma gene into JGN reconstituted expression of functional Ti/CD3 complexes, and analysis of T cell lines producing different amounts of CD3-gamma indicated that CD3-gamma and CD3-delta competed for the binding to CD3-epsilon.......The TCR consists of the Ti alpha beta heterodimer and the associated CD3 chains, CD3 gamma delta epsilon zeta 2 or zeta eta. The structural relationships between the subunits of the Ti/CD3 complex are still not fully understood. To explore the roles of the individual CD3 chains for the assembly......, intracellular processing, and expression of the TCR, mutants of the T cell line Jurkat were isolated. One variant, JGN, was found to produce all the Ti/CD3 components with the exception of CD3-gamma. The results indicate that: 1) the tetrameric form (Ti alpha beta-CD3 delta epsilon) of the Ti/CD3 complex...

  10. Study of multi-quasiparticle band structures in 197Tl using α beam

    International Nuclear Information System (INIS)

    Mukherjee, G.; Nandi, S.; Pai, H.

    2016-01-01

    Study of the multi-quasiparticle (qp) states and the band structures built on them in the neutron deficient Tl nuclei in A ∼ 190 mass region provides useful information on particle-hole interaction in the heavy nuclei. In order to investigate the multi-qp band structures we have studied the excited states in 197 Tl by gamma ray spectroscopy

  11. Gamma radiation in space and in the atmosphere; Rayonnement gamma dans l'espace et dans l'atmosphere

    Energy Technology Data Exchange (ETDEWEB)

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

    1966-07-01

    We have shown that the {gamma} radiation existing in the atmosphere is caused mainly by the Bremsstrahlung of the electrons of the electromagnetic cascades ({approx} 50 per cent of the measured radiation), by the 511 keV radiation produced by the annihilation of positrons created in cascades (8 per cent of the measured intensity) and by the Compton {gamma} degradation of this line (30 per cent of the measured intensity). The rest, slightly over 10 per cent, must be attributed to secondary causes such as the nuclear de-excitation {gamma} to the internal Bremsstrahlung of charged particles created in nuclear stars, and to charged particles crossing our detector, since the latter was not fitted with a device for rejecting these particles. Experiments carried out in rockets at Colomb-Bechar confirm these results and have made it possible to detect and measure a primary {gamma} radiation having an intensity of {approx} 2 {gamma} cm{sup 2} s{sup -1} above 100 keV. The primary spectrum obeys an approximate E{sup -2} law. (author) [French] Nous avons montre que le rayonnement {gamma} existant dans l'atmosphere est provoque principalement por le bremsstrohlung des electrons des cascades electromagnetiques ({approx} 50 pour cent du rayonnement mesure), au rayonnement 511 keV provoque par l'annihilation des positrons crees dans les cascades (8 pour cent de l'intensite mesuree) et aux {gamma} de degradation Compton de cette raie (30 pour cent de l'intensite mesuree). Le reste, soit un peu plus de 10 pour cent, doit etre attribue a des causes secondaires telles que les {gamma} de desexcitation nucleaire, le bremsstrahlung interne des particules chargees creees dans les etoiles nucleaires, et aux particules chargees traversant notre detecteur car celui-ci ne comportait pas de dispositif de rejet de ces particules. Les experiences faites en fusees a Colomb-Bechar ont confirme ces resultats et permis de detecter et mesurer un rayonnement {gamma} primaire dont l

  12. Selection of mutants of capsicum annuum induced by gamma ray

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y. I.; Lee, Y. B. [Korea Atomic Energy Research Institute, Taejeon (Korea, Republic of); Lee, E. K. [Chungnam National Univ., Taejeon (Korea, Republic of)

    1998-06-01

    For induction and selection of mutations of Capsicum annuum L., dry seeds of pure lines No.1 and No.2 were irradiated with gamma ray of 150Gy, 200Gy and 250Gy. Various mutants were selected such as showing early maturity, short plant height, long fruit and chlorophyll mutations. Mutation frequency of No.1 line was 3.4% in the dose of 150Gy, while the frequency of No.2 line was 2.7% in the dose of 250Gy. For selection of resistant mutant to amino acid analog, the optimum concentration of 5-methyltryptophan (5-MT) and S-(2-aminoethyl)-L-cysteine were 25 ppm and 30 ppm, respectively. Four resistant mutant lines to 5-MT were selected among 400 mutant lines.

  13. Gamma-ray production cross-sections for the interactions of 14.9 MeV neutrons with Si, Cu, Nb and Pb

    International Nuclear Information System (INIS)

    Fan Guoying

    1991-12-01

    Gamma rays produced in the interactions of 14.9 MeV neutrons with Si, Cu, Nb and Pb targets were studied. The neutron beam was produced with the T(d,n)He reaction using 300 KeV Cockroft-Walton accelerator. Absolute neutron flux was determined by the associated particle technique. The time-of-flight technique was used to reduce the background. The FWHM of neutron pulses was 1.5 ns. A Ge(Li) detector was used for gamma-ray detection. 39 gamma lines for Si, 39 gamma lines for Cu, 79 for Nb and 39 for Pb were detected. Most of these gamma rays were emitted in (n,γ), (n,n') and (n,2n) reactions. The measurements were made at 40 deg. C, 55 deg. C, 125 deg. C and 140 deg. C relative to the incident neutron beam. The results are presented in the form of the data tables. 9 refs, 11 figs, 19 tabs

  14. Overactivation of phospholipase C-gamma1 renders platelet-derived growth factor beta-receptor-expressing cells independent of the phosphatidylinositol 3-kinase pathway for chemotaxis

    DEFF Research Database (Denmark)

    Rönnstrand, L; Siegbahn, A; Rorsman, C

    1999-01-01

    ., Siegbahn, A. , Rorsman, C., Engström, U., Wernstedt, C., Heldin, C.-H., and Rönnstrand, L. (1996) EMBO J. 15, 5299-5313). Here we show that the increased chemotaxis correlates with increased activation of phospholipase C-gamma1 (PLC-gamma1), measured as inositol-1,4, 5-trisphosphate release. By two......-dimensional phosphopeptide mapping, the increase in phosphorylation of PLC-gamma1 was shown not to be selective for any site, rather a general increase in phosphorylation of PLC-gamma1 was seen. Specific inhibitors of protein kinase C, bisindolylmaleimide (GF109203X), and phosphatidylinositol 3-kinase (PI3-kinase), LY294002......, did not affect the activation of PLC-gamma1. To assess whether increased activation of PLC-gamma1 is the cause of the hyperchemotactic behavior of the Y934F mutant cell line, we constructed cell lines expressing either wild-type or a catalytically compromised version of PLC-gamma1 under a tetracycline...

  15. Calculation method for gamma dose rates from Gaussian puffs

    Energy Technology Data Exchange (ETDEWEB)

    Thykier-Nielsen, S; Deme, S; Lang, E

    1995-06-01

    The Lagrangian puff models are widely used for calculation of the dispersion of releases to the atmosphere. Basic output from such models is concentration of material in the air and on the ground. The most simple method for calculation of the gamma dose from the concentration of airborne activity is based on the semi-infinite cloud model. This method is however only applicable for puffs with large dispersion parameters, i.e. for receptors far away from the release point. The exact calculation of the cloud dose using volume integral requires large computer time usually exceeding what is available for real time calculations. The volume integral for gamma doses could be approximated by using the semi-infinite cloud model combined with correction factors. This type of calculation procedure is very fast, but usually the accuracy is poor because only a few of the relevant parameters are considered. A multi-parameter method for calculation of gamma doses is described here. This method uses precalculated values of the gamma dose rates as a function of E{sub {gamma}}, {sigma}{sub y}, the asymmetry factor - {sigma}{sub y}/{sigma}{sub z}, the height of puff center - H and the distance from puff center R{sub xy}. To accelerate the calculations the release energy, for each significant radionuclide in each energy group, has been calculated and tabulated. Based on the precalculated values and suitable interpolation procedure the calculation of gamma doses needs only short computing time and it is almost independent of the number of radionuclides considered. (au) 2 tabs., 15 ills., 12 refs.

  16. Geological interpretation of an airborne gamma-ray spectrometer survey of the Hearne Lake area, Northwest Territories

    International Nuclear Information System (INIS)

    Newton, A.R.; Slaney, V.R.

    1978-01-01

    This study shows how large volumes of airborne data can be displayed in a simple format which provides both mapping and exploration geologists with information not easily obtained from the original data. Eleven lines or part-lines from a gamma-ray survey of the Hearne Lake area were chosen as test lines, and airphotos were used to identify outcrops of each rock type and the distribution of overburden, swamp and water along each line. Geological maps were used to locate the test lines and to provide a listing of the rock types in the area. With this information, it was possible to calculate the average radioelement characteristics of each rock type and to group the rock signatures into a number of rock classes. The techniques described are most usefully applied to those areas where the outcrop is extensive, where some form of geological map already exists, where there are airphotos at scales of 1:30,000 or larger, and where the gamma-ray survey lines are less than 2.5 km apart

  17. TESTING THE POSSIBLE INTRINSIC ORIGIN OF THE EXCESS VERY STRONG Mg II ABSORBERS ALONG GAMMA-RAY BURST LINES-OF-SIGHT

    International Nuclear Information System (INIS)

    Cucchiara, A.; Jones, T.; Charlton, J. C.; Fox, D. B.; Einsig, D.; Narayanan, A.

    2009-01-01

    The startling discovery by Prochter et al. that the frequency of very strong (W r (2796)>1 A) Mg II absorbers along gamma-ray burst (GRB) lines of sight ([dN/dz] GRB = 0.90) is more than three times the frequency along quasar lines of sight ([dN/dz] QSO = 0.24), over similar redshift ranges, has yet to be understood. In particular, explanations appealing to dust antibias in quasar samples, partial covering of the quasar sources, and gravitational-lensing amplification of the GRBs have all been carefully examined and found wanting. We therefore reconsider the possibility that the excess of very strong Mg II absorbers toward GRBs is intrinsic either to the GRBs themselves or to their immediate environment, and associated with bulk outflows with velocities as large as v max ∼ 0.3c. In order to examine this hypothesis, we accumulate a sample of 27 W r (2796)>1 A absorption systems found toward 81 quasars, and compare their properties to those of 8 W r (2796) > 1 A absorption systems found toward six GRBs; all systems have been observed at high spectral resolution (R = 45, 000) using the Ultraviolet and Visual Echelle Spectrograph on the Very Large Telescope. We make multiple comparisons of the absorber properties across the two populations, testing for differences in metallicity, ionization state, abundance patterns, dust abundance, kinematics, and phase structure. We find no significant differences between the two absorber populations using any of these metrics, implying that, if the excess of absorbers along GRB lines of sight are indeed intrinsic, they must be produced by a process which has strong similarities to the processes yielding strong Mg II systems associated with intervening galaxies. Although this may seem a priori unlikely, given the high outflow velocities required for any intrinsic model, we note that the same conclusion was reached, recently, with respect to the narrow absorption line systems seen in some quasars.

  18. Cytotoxic potential and chromatogram profile of sarang semut tuber (Myrmecodia Pendans Merr. & Perry) after gamma irradiation

    International Nuclear Information System (INIS)

    Ermin Katrin Winarno; Susanto; Hendig Winarno; Siva Fauziah

    2015-01-01

    Sarang semut tuber (Myrmecodia pendans Merr. & Perry) has cytotoxic activity. Preservation efforts of sarang semut tuber was performed with gamma irradiation. The research purposed to study the effect of gamma on cytotoxic activity against leukemia L1210 cell lines and chromatogram profiles of sarang semut tuber (Myrmecodia pendans Merr. & Perry). The dried sarang semut tuber were gamma irradiated with a variety of doses of 5; 7.5; 10; and 15 kGy. The experiments were performed with two replicates for each dose. Then samples were macerated with solvent by gradient polarity with n-hexane, ethyl acetate, and ethanol. Extracts were tested against the leukemia L1210 cell lines. From the results obtained showed that the ethanol extract was the most active against leukemia L1210 cell lines (IC50 9.88 μg/ml) compared with n-heksan (IC50 23.44 μg/ml) and ethyl acetate extract (IC50 17.32 μg/ml). Ethanol extracts were fractionated by column chromatography, the result were obtained 7 fractions. Based on the cytotoxic activity test for each fraction, the fraction 1 had the highest activity (IC50 ≤ 3.23 μg/ml). The identifications of ethanol extract and fraction 1 by CLT-densitometry showed that the spots area increased and decreased after gamma irradiation. The chromatogram profile of fraction 1 showed that the major peak area decreased after irradiation. The maximum irradiation dose without damaging the cytotoxic activity of sarang semut tuber againts leukemia L1210 cell lines was 5 kGy. (author)

  19. Neutron and gamma sensitivities of self-powered detectors: Monte Carlo modelling

    Energy Technology Data Exchange (ETDEWEB)

    Vermeeren, Ludo [SCK-CEN, Nuclear Research Centre, Boeretang 200, B-2400 Mol, (Belgium)

    2015-07-01

    This paper deals with the development of a detailed Monte Carlo approach for the calculation of the absolute neutron sensitivity of SPNDs, which makes use of the MCNP code. We will explain the calculation approach, including the activation and beta emission steps, the gamma-electron interactions, the charge deposition in the various detector parts and the effect of the space charge field in the insulator. The model can also be applied for the calculation of the gamma sensitivity of self-powered detectors and for the radiation-induced currents in signal cables. The model yields detailed information on the various contributions to the sensor currents, with distinct response times. Results for the neutron sensitivity of various types of SPNDs are in excellent agreement with experimental data obtained at the BR2 research reactor. For typical neutron to gamma flux ratios, the calculated gamma induced SPND currents are significantly lower than the neutron induced currents. The gamma sensitivity depends very strongly upon the immediate detector surroundings and on the gamma spectrum. Our calculation method opens the way to a reliable on-line determination of the absolute in-pile thermal neutron flux. (authors)

  20. Gamma ray energy tracking in GRETINA

    Science.gov (United States)

    Lee, I. Y.

    2011-10-01

    The next generation of stable and exotic beam accelerators will provide physics opportunities to study nuclei farther away from the line of stability. However, these experiments will be more demanding on instrumentation performance. These come from the lower production rate for more exotic beams, worse beam impurities, and large beam velocity from the fragmentation and inverse reactions. Gamma-ray spectroscopy will be one of the most effective tools to study exotic nuclei. However, to fully exploit the physics reach provided by these new facilities, better gamma-ray detector will be needed. In the last 10 years, a new concept, gamma-ray energy tracking array, was developed. Tracking arrays will increase the detection sensitivity by factors of several hundred compared to current arrays used in nuclear physics research. Particularly, the capability of reconstructing the position of the interaction with millimeters resolution is needed to correct the Doppler broadening of gamma rays emitted from high velocity nuclei. GRETINA is a gamma-ray tracking array which uses 28 Ge crystals, each with 36 segments, to cover ¼ of the 4 π of the 4 π solid angle. The gamma ray tracking technique requires detailed pulse shape information from each of the segments. These pulses are digitized using 14-bit 100 MHz flash ADCs, and digital signal analysis algorithms implemented in the on-board FPGAs provides energy, time and selection of pulse traces. A digital trigger system, provided flexible trigger functions including a fast trigger output, and also allows complicated trigger decisions to be made up to 20 microseconds. Further analyzed, carried out in a computer cluster, determine the energy, time, and three-dimensional positions of all gamma-ray interactions in the array. This information is then utilized, together with the characteristics of Compton scattering and pair-production processes, to track the scattering sequences of the gamma rays. GRETINA construction is completed in

  1. The progress of neutron induced prompt gamma analysis technique in 1988-2002

    International Nuclear Information System (INIS)

    Liu Yuren; Jing Shiwei

    2003-01-01

    The new development of the neutron induced prompt gamma-ray analysis (NIPGA) technology in 1988-2002 are described. The pulse fast-thermal neutron activation analysis method, which utilizes the inelastic reaction and capture reaction jointly is employed to measure the elemental content in the material more efficiently. The lifetime of the neutron generator is more than 10000 h and the capability of HPGe, TeZeCd and MCA (multi-channel analyser) reaches the high level. At the same time, Monte Carlo Library least-square method is used to solve the nonlinearity problem in the PGNAA (Prompt Gamma Neutron Activation Analysis)

  2. Searches for Particle Dark Matter with gamma-rays.

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    In this contribution I review the present status and discuss some prospects for indirect detection of dark matter with gamma-rays. Thanks to the Fermi Large Area Telescope, searches in gamma-rays have reached sensitivities that allow to probe the most interesting parameter space of the weakly interacting massive particles (WIMP) paradigm. This gain in sensitivity is naturally accompanied by a number of detection claims or indications, the most recent being the claim of a line feature at a dark matter particle mass of ∼ 130 GeV at the Galactic Centre, a claim which requires confirmation from the Fermi-LAT collaboration and other experiments, for example HESS II or the planned Gamma-400 satellite. Predictions for the next generation air Cherenkov telescope, Cherenkov Telescope Array (CTA), together with forecasts on future Fermi-LAT constraints arrive at the exciting possibility that the cosmological benchmark cross-section could be probed from masses of a few GeV to a few TeV. Consequently, non-detection wou...

  3. Einstein@Home discovers a radio-quiet gamma-ray millisecond pulsar.

    Science.gov (United States)

    Clark, Colin J; Pletsch, Holger J; Wu, Jason; Guillemot, Lucas; Kerr, Matthew; Johnson, Tyrel J; Camilo, Fernando; Salvetti, David; Allen, Bruce; Anderson, David; Aulbert, Carsten; Beer, Christian; Bock, Oliver; Cuéllar, Andres; Eggenstein, Heinz-Bernd; Fehrmann, Henning; Kramer, Michael; Kwang, Shawn A; Machenschalk, Bernd; Nieder, Lars; Ackermann, Markus; Ajello, Marco; Baldini, Luca; Ballet, Jean; Barbiellini, Guido; Bastieri, Denis; Bellazzini, Ronaldo; Bissaldi, Elisabetta; Blandford, Roger D; Bloom, Elliott D; Bonino, Raffaella; Bottacini, Eugenio; Brandt, Terri J; Bregeon, Johan; Bruel, Philippe; Buehler, Rolf; Burnett, Toby H; Buson, Sara; Cameron, Rob A; Caputo, Regina; Caraveo, Patrizia A; Cavazzuti, Elisabetta; Cecchi, Claudia; Charles, Eric; Chekhtman, Alexandre; Ciprini, Stefano; Cominsky, Lynn R; Costantin, Denise; Cutini, Sara; D'Ammando, Filippo; De Luca, Andrea; Desiante, Rachele; Di Venere, Leonardo; Di Mauro, Mattia; Di Lalla, Niccolò; Digel, Seth W; Favuzzi, Cecilia; Ferrara, Elizabeth C; Franckowiak, Anna; Fukazawa, Yasushi; Funk, Stefan; Fusco, Piergiorgio; Gargano, Fabio; Gasparrini, Dario; Giglietto, Nico; Giordano, Francesco; Giroletti, Marcello; Gomez-Vargas, Germán A; Green, David; Grenier, Isabelle A; Guiriec, Sylvain; Harding, Alice K; Hewitt, John W; Horan, Deirdre; Jóhannesson, Guðlaugur; Kensei, Shiki; Kuss, Michael; La Mura, Giovanni; Larsson, Stefan; Latronico, Luca; Li, Jian; Longo, Francesco; Loparco, Francesco; Lovellette, Michael N; Lubrano, Pasquale; Magill, Jeffrey D; Maldera, Simone; Manfreda, Alberto; Mazziotta, Mario N; McEnery, Julie E; Michelson, Peter F; Mirabal, Nestor; Mitthumsiri, Warit; Mizuno, Tsunefumi; Monzani, Maria Elena; Morselli, Aldo; Moskalenko, Igor V; Nuss, Eric; Ohsugi, Takashi; Omodei, Nicola; Orienti, Monica; Orlando, Elena; Palatiello, Michele; Paliya, Vaidehi S; de Palma, Francesco; Paneque, David; Perkins, Jeremy S; Persic, Massimo; Pesce-Rollins, Melissa; Porter, Troy A; Principe, Giacomo; Rainò, Silvia; Rando, Riccardo; Ray, Paul S; Razzano, Massimiliano; Reimer, Anita; Reimer, Olaf; Romani, Roger W; Saz Parkinson, Pablo M; Sgrò, Carmelo; Siskind, Eric J; Smith, David A; Spada, Francesca; Spandre, Gloria; Spinelli, Paolo; Thayer, Jana B; Thompson, David J; Torres, Diego F; Troja, Eleonora; Vianello, Giacomo; Wood, Kent; Wood, Matthew

    2018-02-01

    Millisecond pulsars (MSPs) are old neutron stars that spin hundreds of times per second and appear to pulsate as their emission beams cross our line of sight. To date, radio pulsations have been detected from all rotation-powered MSPs. In an attempt to discover radio-quiet gamma-ray MSPs, we used the aggregated power from the computers of tens of thousands of volunteers participating in the Einstein@Home distributed computing project to search for pulsations from unidentified gamma-ray sources in Fermi Large Area Telescope data. This survey discovered two isolated MSPs, one of which is the only known rotation-powered MSP to remain undetected in radio observations. These gamma-ray MSPs were discovered in completely blind searches without prior constraints from other observations, raising hopes for detecting MSPs from a predicted Galactic bulge population.

  4. Japanese VLBI Network Observations of a Gamma-Ray Narrow ...

    Indian Academy of Sciences (India)

    J. Astrophys. Astr. (2014) 35, 215–218 c Indian Academy of Sciences. Japanese VLBI Network Observations of a Gamma-Ray. Narrow-Line Seyfert 1 Galaxy 1H 0323+342. Kiyoaki Wajima1,∗. , Kenta Fujisawa2, Masaaki Hayashida3. & Naoki Isobe4. 1Shanghai Astronomical Observatory, Chinese Academy of Sciences,.

  5. Development of aerial gamma radiation survey system III

    International Nuclear Information System (INIS)

    Nagaoka, Toshi; Sakamoto, Ryuichi; Saito, Kimiaki; Tsutsumi, Masahiro; Moriuchi, Shigeru; Miyasaka, Satoshi.

    1985-01-01

    An aerial gamma-ray survey system using a helicopter has been developed since 1980 in order to perform quick gamma-ray survey covering a wide area. To form a line in the chain of the development, a series of flight measurements were conducted in Watarase reservoir, Tochigi prefecture, in which artificial gamma-ray fields were realized using 60 Co (100 and 400 mCi) and 137 Cs (100 and 300 mCi) point sources located on the ground. For the purpose of obtaining gamma-ray pulse height spectra in the field, 6 sets of NaI(Tl) scientillation detectors were prepared. These sets of detectors consist of ones for evaluation with high accuracy as the standard, for intercomparison with other authors' results, and for practical use. Two sets of them were boarded for each flight considering the exposure rate level and detector's sensitivity. The flight measurements were performed in a space of 20 m to 500 m in altitude, and 0 m to 500 m in horizontal distance from the source. The experimental results of the spatial gamma-ray distribution for each gamma-ray field satisfactorily agreed with calculational results by Monte Carlo method. Throughout this experiment, characteristics of this survey system and detectors were clarified, and versatile data processing and analysis code was completed. Also, a method for subtraction of background exposure rate in a field including artificial radiation component was discussed using energy band information, and the coefficients for this method were determined. These data obtained are expected to be used as widely applicable data not only for the interpretation of measured value, but also for analysis of environmental gamma-ray field. (author)

  6. Electron-nuclear. gamma. transition spectrum of a nucleus in a multicharged atomic ion

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, L N; Letokhov, V S

    1987-08-01

    The nuclear emission of absorption spectrum of an atom possesses a set of electron satelites which are due to an alternation of the state of the electron shell. It is shown that the mechanism of formation of the satellites might be different for neutral atoms and high-charge ions. In the first case (loose electron shell) a ''shaking'' of the shell resulting from the interaction between the nucleus and ..gamma.. quantum is predominant. In the second case (rigid electron shell) the mechanism involves a direct interaction between the ..gamma.. quantum and electrons. The second mechanism is important in the case of dipole nuclear transitions and dominates at ..gamma.. quantum energies gamma.. quantum emission and absorption lines are not overlapped by the Doppler contour of the ..gamma.. line.

  7. Upgrade of the JET gamma-ray cameras

    International Nuclear Information System (INIS)

    Soare, S.; Curuia, M.; Anghel, M.; Constantin, M.; David, E.; Craciunescu, T.; Falie, D.; Pantea, A.; Tiseanu, I.; Kiptily, V.; Prior, P.; Edlington, T.; Griph, S.; Krivchenkov, Y.; Loughlin, M.; Popovichev, S.; Riccardo, V; Syme, B.; Thompson, V.; Lengar, I.; Murari, A.; Bonheure, G.; Le Guern, F.

    2007-01-01

    Full text: The JET gamma-ray camera diagnostics have already provided valuable information on the gamma-ray imaging of fast ion in JET plasmas. The applicability of gamma-ray imaging to high performance deuterium and deuterium-tritium JET discharges is strongly dependent on the fulfilment of rather strict requirements for the characterisation of the neutron and gamma-ray radiation fields. These requirements have to be satisfied within very stringent boundary conditions for the design, such as the requirement of minimum impact on the co-existing neutron camera diagnostics. The JET Gamma-Ray Cameras (GRC) upgrade project deals with these issues with particular emphasis on the design of appropriate neutron/gamma-ray filters ('neutron attenuators'). Several design versions have been developed and evaluated for the JET GRC neutron attenuators at the conceptual design level. The main design parameter was the neutron attenuation factor. The two design solutions, that have been finally chosen and developed at the level of scheme design, consist of: a) one quasi-crescent shaped neutron attenuator (for the horizontal camera) and b) two quasi-trapezoid shaped neutron attenuators (for the vertical one). The second design solution has different attenuation lengths: a short version, to be used together with the horizontal attenuator for deuterium discharges, and a long version to be used for high performance deuterium and DT discharges. Various neutron-attenuating materials have been considered (lithium hydride with natural isotopic composition and 6 Li enriched, light and heavy water, polyethylene). Pure light water was finally chosen as the attenuating material for the JET gamma-ray cameras. The neutron attenuators will be steered in and out of the detector line-of-sight by means of an electro-pneumatic steering and control system. The MCNP code was used for neutron and gamma ray transport in order to evaluate the effect of the neutron attenuators on the neutron field of the

  8. Radiation sensitivity of Merkel cell carcinoma cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, J.H.; Ramsay, J.R.; Birrell, G.W. [Queensland Institute of Medical Research (Australia)] [and others

    1995-07-30

    Merkel cell carcinoma (MCC), being a small cell carcinoma, would be expected to be sensitive to radiation. Clinical analysis of patients at our center, especially those with macroscopic disease, would suggest the response is quite variable. We have recently established a number of MCC cell lines from patients prior to radiotherapy, and for the first time are in a position to determine their sensitivity under controlled conditions. Some of the MCC lines grew as suspension cultures and could not be single cell cloned; therefore, it was not possible to use clonogenic survival for all cell lines. A tetrazolium based (MTT) assay was used for these lines, to estimate cell growth after {gamma} irradiation. Control experiments were conducted on lymphoblastoid cell lines (LCL) and the adherent MCC line, MCC13, to demonstrate that the two assays were comparable under the conditions used. We have examined cell lines from MCC, small cell lung cancer (SCLC), malignant melanomas, Epstein Barr virus (EBV) transformed lymphocytes (LCL), and skin fibroblasts for their sensitivity to {gamma} irradiation using both clonogenic cell survival and MTT assays. The results show that the tumor cell lines have a range of sensitivities, with melanoma being more resistant (surviving fraction at 2 Gy (SF2) 0.57 and 0.56) than the small cell carcinoma lines, MCC (SF2 range 0.21-0.45, mean SF2 0.30, n = 8) and SCLC (SF2 0.31). Fibroblasts were the most sensitive (SF2 0.13-0.20, mean 0.16, n = 5). The MTT assay, when compared to clonogenic assay for the MCC13 adherent line and the LCL, gave comparable results under the conditions used. Both assays gave a range of SF2 values for the MCC cell lines, suggesting that these cancers would give a heterogeneous response in vivo. The results with the two derivative clones of MCC14 (SF2 for MCC14/1 0.38, MCC14/2 0.45) would further suggest that some of them may develop resistance during clonogenic evolution. 25 refs., 3 figs., 1 tab.

  9. Sesame mutation induction: Improvement of non-shattering capsule by using gamma rays and EMS

    International Nuclear Information System (INIS)

    Wongyai, W.; Saengkaewsook, W.; Veerawudh, J.

    2001-01-01

    Improvement of non-shattering capsule by using gamma rays and EMS in the Kasetsart University Sesame Breeding Project has been carried out since November 1994. Seed treatments with gamma rays (500 Gy) and EMS (0.5 and 1.0%, 4 hrs) were used. Growth characteristics, delayed shattering and shatter resistance of capsule were investigated in M 2 through M 8 lines. The seed yield of thirty promising M 7 lines was evaluated in April 1997 at Suwan Farm, Pakchong, Nakorn Ratchasima. Most of the tested lines gave higher seed yields than the check variety, MK 60. M 6026 gave the highest seed yield (1,477 kg/ha). All the tested mutant lines had a longer period of growth during flowering (GF). However, three promising lines had a shorter flowering period (FP) and a degree of stem termination (DST) when they were planted both in April and August 1997. Based on the criteria of determinate growth studied, these mutant lines would be classified as having a determinate growth habit. Delayed shattering and shatter resistant capsule were obtained. It is noted that the promising mutant lines were obtained from EMS treatment. Thus, the study of these mutant lines revealed that the improvement of sesame by mutation breeding for reduced seed losses before or during the harvest can be successful. (author)

  10. A novel method for quantitative geosteering using azimuthal gamma-ray logging

    International Nuclear Information System (INIS)

    Yuan, Chao; Zhou, Cancan; Zhang, Feng; Hu, Song; Li, Chaoliu

    2015-01-01

    A novel method for quantitative geosteering by using azimuthal gamma-ray logging is proposed. Real-time up and bottom gamma-ray logs when a logging tool travels through a boundary surface with different relative dip angles are simulated with the Monte Carlo method. Study results show that response points of up and bottom gamma-ray logs when the logging tool moves towards a highly radioactive formation can be used to predict the relative dip angle, and then the distance from the drilling bit to the boundary surface is calculated. - Highlights: • A new method is proposed for geosteering by using azimuthal gamma-ray logging. • The new method can quantitatively determine the distance from the drilling bit to the boundary surface while the traditional geosteering method can only qualitatively guide the drilling bit in reservoirs. • The response points of real-time upper and lower gamma line when the logging tool meets high radioactive formation are used to predict the relative dip angles, and then the distance from the drilling bit to the boundary surface is calculated

  11. Line broadening analysis of implosion core conditions at Z using argon K-shell spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Burris-Mog, T.J. [Department of Physics, University of Nevada, Reno, NV 89557 (United States)]. E-mail: burris@physics.unr.edu; Mancini, R.C. [Sandia National Laboratories, Albuquerque, NM 87185 (United States); Bailey, J.E. [Sandia National Laboratories, Albuquerque, NM 87185 (United States); Chandler, G.A. [Sandia National Laboratories, Albuquerque, NM 87185 (United States); Rochau, G. [Sandia National Laboratories, Albuquerque, NM 87185 (United States); Dunham, G. [Sandia National Laboratories, Albuquerque, NM 87185 (United States); Lake, P.W. [Sandia National Laboratories, Albuquerque, NM 87185 (United States); Peterson, K. [Sandia National Laboratories, Albuquerque, NM 87185 (United States); Slutz, S.A. [Sandia National Laboratories, Albuquerque, NM 87185 (United States); Mehlhorn, T.A. [Sandia National Laboratories, Albuquerque, NM 87185 (United States); Golovkin, I.E. [Prism Computational Sciences, Madison, WI 53703 (United States); MacFarlane, J.J. [Prism Computational Sciences, Madison, WI 53703 (United States)

    2006-05-15

    We report on spectral line broadening analysis of Ar K-shell lines from argon-doped implosion cores driven by a dynamic hohlraum z-pinch. The observed Ar spectra include emissions from the resonance series in H- and He-like Ar ions, i.e., Ly{alpha}, Ly{beta} and Ly{gamma}, and He{alpha}, He{beta}, He{gamma} and He{delta} lines, respectively. The analysis accounts for opacity and Stark broadening to determine electron density, N{sub e}, and areal-density, N{delta}R, values for the ground state populations of H- and He-like Ar ions. Furthermore, these results are combined with the ratio of H- and He-like ground state populations to extract the electron temperature, T{sub e}.

  12. GAMMA RAYS FROM TYPE Ia SUPERNOVA SN 2014J

    International Nuclear Information System (INIS)

    Churazov, E.; Sunyaev, R.; Grebenev, S.; Isern, J.; Bikmaev, I.; Bravo, E.; Chugai, N.; Jean, P.; Knödlseder, J.; Lebrun, F.; Kuulkers, E.

    2015-01-01

    The whole set of INTEGRAL observations of Type Ia supernova SN 2014J, covering the period 19–162 days after the explosion, has been analyzed. For spectral fitting the data are split into early and late periods covering days 19–35 and 50–162, respectively, optimized for 56 Ni and 56 Co lines. As expected for the early period, much of the gamma-ray signal is confined to energies below ∼200 keV, while for the late period it is strongest above 400 keV. In particular, in the late period, 56 Co lines at 847 and 1248 keV are detected at 4.7σ and 4.3σ, respectively. The light curves in several representative energy bands are calculated for the entire period. The resulting spectra and light curves are compared with a subset of models. We confirm our previous finding that the gamma-ray data are broadly consistent with the expectations for canonical one-dimensional models, such as delayed detonation or deflagration models for a near-Chandrasekhar mass white dwarf. Late optical spectra (day 136 after the explosion) show rather symmetric Co and Fe line profiles, suggesting that, unless the viewing angle is special, the distribution of radioactive elements is symmetric in the ejecta

  13. Compton suppression gamma ray spectrometry

    International Nuclear Information System (INIS)

    Landsberger, S.; Iskander, F.Y.; Niset, M.; Heydorn, K.

    2002-01-01

    In the past decade there have been many studies to use Compton suppression methods in routine neutron activation analysis as well as in the traditional role of low level gamma ray counting of environmental samples. On a separate path there have been many new PC based software packages that have been developed to enhance photopeak fitting. Although the newer PC based algorithms have had significant improvements, they still suffer from being effectively used in weak gamma ray lines in natural samples or in neutron activated samples that have very high Compton backgrounds. We have completed a series of experiments to show the usefulness of Compton suppression. As well we have shown the pitfalls when using Compton suppression methods for high counting deadtimes as in the case of neutron activated samples. We have also investigated if counting statistics are the same both suppressed and normal modes. Results are presented in four separate experiments. (author)

  14. Multi-TeV gamma ray and cosmic ray astrophysics with TAIGA

    Energy Technology Data Exchange (ETDEWEB)

    Tluczykont, Martin [Hamburg Univ. (Germany). Institut fuer Experimentalphysik; Collaboration: TAIGA Kollaboration

    2016-07-01

    The very high energy gamma-ray regime is the key to several questions in high energy astrophysics, the most prominent being the search for the origin of cosmic rays. Observations of gamma rays up to several 100 TeV are particularly important to spectrally resolve the cutoff regime of the long-sought Pevatrons, the accelerators of PeV cosmic rays. TAIGA is an international collaboration that has, in the past 3 years, installed the air Cherenkov timing array HiSCORE on an area of 0.25 square-km, and are currently installing a first 4m diameter imaging air Cherenkov telescope (IACT), to be operated in parallel with the timing array. Our aim is to combine the timing and imaging techniques on a large scale in order to optimize the air Cherenkov detection technique for energies above 10 TeV and up to several 100 TeV. Simulations show a clear potential of the planned hybrid event reconstruction, especially in the energy regime from 10 TeV to 100 TeV. The TAIGA experiment will be complemented by scintillator based particle detectors for a measurement of the muon content of the air shower at higher energies. The status of our experiment and the planned 1 square-km stage of TAIGA are discussed.

  15. Multi-scale strategies for dealing with moving contact lines

    Science.gov (United States)

    Smith, Edward R.; Theodorakis, Panagiotis; Craster, Richard V.; Matar, Omar K.

    2017-11-01

    Molecular dynamics (MD) has great potential to elucidate the dynamics of the moving contact line. As a more fundamental model, it can provide a priori results for fluid-liquid interfaces, surface tension, viscosity, phase change, and near wall stick-slip behaviour which typically show very good agreement to experimental results. However, modelling contact line motion combines all this complexity in a single problem. In this talk, MD simulations of the contact line are compared to the experimental results obtained from studying the dynamics of a sheared liquid bridge. The static contact angles are correctly matched to the experimental data for a range of different electro-wetting results. The moving contact line results are then compared for each of these electro-wetting values. Despite qualitative agreement, there are notable differences between the simulation and experiments. Many MD simulation have studied contact lines, and the sheared liquid bridge, so it is of interest to review the limitations of this setup in light of this discrepancy. A number of factors are discussed, including the inter-molecular interaction model, molecular-scale surface roughness, model of electro-wetting and, perhaps most importantly, the limited system sizes possible using MD simulation. EPSRC, UK, MEMPHIS program Grant (EP/K003976/1), RAEng Research Chair (OKM).

  16. GRB 161219B / SN 2016jca: A low-redshift gamma-ray burst supernova powered by radioactive heating

    DEFF Research Database (Denmark)

    Cano, Z.; Izzo, L.; De Ugarte Postigo, A.

    2017-01-01

    Since the first discovery of a broad-lined type Ic supernova (SN) with a long-duration gamma-ray burst (GRB) in 1998, fewer than fifty gamma-ray burst supernovae (GRB-SNe) have been discovered. The intermediate-luminosity Swift GRB 161219B and its associated supernova SN 2016jca, which occurred a...

  17. Photoneutron cross sections measurements in 9Be, 13C e 17O with thermal neutron capture gamma-rays

    International Nuclear Information System (INIS)

    Semmler, Renato

    2006-01-01

    Photoneutron cross sections measurements of 9 Be, 13 C and 17 O have been obtained in the energy interval between 1,6 and 10,8 MeV, using neutron capture gamma-rays with high resolution in energy (3 a 21 eV), produced by 21 target materials, placed inside a tangential beam port, near the core of the IPEN/CNEN-SP IEA-R1 (5 MW) research reactor. The samples have been irradiated inside a 4π geometry neutron detector system 'Long Counter', 520,5 cm away from the capture target. The capture gamma-ray flux was determined by means of the analysis of the gamma spectrum obtained by using a Ge(Li) solid-state detector (EG and G ORTEC, 25 cm 3 , 5%), previously calibrated with capture gamma-rays from a standard target of Nitrogen (Melamine). The neutron photoproduction cross section has been measured for each target capture gamma-ray spectrum (compound cross section). A inversion matrix methodology to solve inversion problems for unfolding the set of experimental compound cross sections, was used in order to obtain the cross sections at specific excitation energy values (principal gamma line energies of the capture targets). The cross sections obtained at the energy values of the principal gamma lines were compared with experimental data reported by other authors, with have employed different gamma-ray sources. A good agreement was observed among the experimental data in this work with reported in the literature. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-10-01

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

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

    Science.gov (United States)

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

    2017-10-01

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

  20. The advantage of using the henry straight line in {gamma} spectrometry (1963); Interet de l'utilisation de la droite de henry en spectrometrie {gamma} (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1963-07-01

    The Henry construction is a convenient way to interpret the total absorption peaks in gamma spectrometry by exploiting their statistical significance. It is so possible to determine graphically, and accurately, such values as: - position of the peak - resolution, etc. The main practical applications are considered. (author) [French] La construction de la droite de Henry fournit un moyen commode d'interpreter les pics d'absorption totale en spectrometrie gamma en exploitant leur signification statistique, il est ainsi possible de determiner graphiquement, avec precision, des notions telles que: - position du pic - resolution, etc. Les principales applications pratiques sont envisagees. (auteur)

  1. Analysis of a gamma-ray spectrum by using a standard spectrum

    International Nuclear Information System (INIS)

    Tasaka, Kanji

    1975-06-01

    The standard spectrum method has been extended to take into account the energy dependence of a standard spectrum. The method analyses the observed gamma-ray spectrum by the least-square method, using an interpolated standard spectrum for expressing the line shape and a linear function for the background continuum. The interpolated standard spectrum is defined for each fitting interval by interpolating several standard spectra, which are derived directly from the observed spectra of single photopeaks each corresponding to the incident monochromatic gamma-rays by subtracting the background and smoothing the data. (author)

  2. Pharmacological evidences for DFK167-sensitive presenilin-independent gamma-secretase-like activity.

    Science.gov (United States)

    Sevalle, Jean; Ayral, Erwan; Hernandez, Jean-François; Martinez, Jean; Checler, Frédéric

    2009-07-01

    Amyloid-beta (Abeta) peptides production is thought to be a key event in the neurodegenerative process ultimately leading to Alzheimer's disease (AD) pathology. A bulk of studies concur to propose that the C-terminal moiety of Abeta is released from its precursor beta-amyloid precursor protein by a high molecular weight enzymatic complex referred to as gamma-secretase, that is composed of at least, nicastrin (NCT), Aph-1, Pen-2, and presenilins (PS) 1 or 2. They are thought to harbor the gamma-secretase catalytic activity. However, several lines of evidence suggest that additional gamma-secretase-like activities could potentially contribute to Abeta production. By means of a quenched fluorimetric substrate (JMV2660) mimicking the beta-amyloid precursor protein sequence targeted by gamma-secretase, we first show that as expected, this probe allows monitoring of an activity detectable in several cell systems including the neuronal cell line telencephalon specific murine neurons (TSM1). This activity is reduced by DFK167, N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (DAPT), and LY68458, three inhibitors known to functionally interact with PS. Interestingly, JMV2660 but not the unrelated peptide JMV2692, inhibits Abeta production in an in vitrogamma-secretase assay as expected from a putative substrate competitor. This activity is enhanced by PS1 and PS2 mutations known to be responsible for familial forms of AD and reduced by aspartyl mutations inactivating PS or in cells devoid of PS or NCT. However, we clearly establish that residual JMV2660-hydrolysing activity could be recovered in PS- and NCT-deficient fibroblasts and that this activity remained inhibited by DFK167. Overall, our study describes the presence of a proteolytic activity displaying gamma-secretase-like properties but independent of PS and still blocked by DFK167, suggesting that the PS-dependent complex could not be the unique gamma-secretase activity responsible for Abeta

  3. Optimization and verification of image reconstruction for a Compton camera towards application as an on-line monitor for particle therapy

    Science.gov (United States)

    Taya, T.; Kataoka, J.; Kishimoto, A.; Tagawa, L.; Mochizuki, S.; Toshito, T.; Kimura, M.; Nagao, Y.; Kurita, K.; Yamaguchi, M.; Kawachi, N.

    2017-07-01

    Particle therapy is an advanced cancer therapy that uses a feature known as the Bragg peak, in which particle beams suddenly lose their energy near the end of their range. The Bragg peak enables particle beams to damage tumors effectively. To achieve precise therapy, the demand for accurate and quantitative imaging of the beam irradiation region or dosage during therapy has increased. The most common method of particle range verification is imaging of annihilation gamma rays by positron emission tomography. Not only 511-keV gamma rays but also prompt gamma rays are generated during therapy; therefore, the Compton camera is expected to be used as an on-line monitor for particle therapy, as it can image these gamma rays in real time. Proton therapy, one of the most common particle therapies, uses a proton beam of approximately 200 MeV, which has a range of ~ 25 cm in water. As gamma rays are emitted along the path of the proton beam, quantitative evaluation of the reconstructed images of diffuse sources becomes crucial, but it is far from being fully developed for Compton camera imaging at present. In this study, we first quantitatively evaluated reconstructed Compton camera images of uniformly distributed diffuse sources, and then confirmed that our Compton camera obtained 3 %(1 σ) and 5 %(1 σ) uniformity for line and plane sources, respectively. Based on this quantitative study, we demonstrated on-line gamma imaging during proton irradiation. Through these studies, we show that the Compton camera is suitable for future use as an on-line monitor for particle therapy.

  4. Young supernova remnants and INTEGRAL: "4"4Ti lines and non-thermal emission

    International Nuclear Information System (INIS)

    Renaud, M.

    2006-10-01

    This thesis deals with the search for and the study of young galactic supernova remnants using the observations performed by IBIS/ISGRI, one of the two main coded-mask instruments onboard the european gamma-ray satellite INTEGRAL. This research is based on i) the study of gamma-ray lines coming from the radioactive decay of "4"4Ti, a short-lived nucleus (τ∼ 86 y) exclusively produced during the first stages of stellar explosions, and ii) the study of the nonthermal continuum mechanisms which take place inside the young supernova remnants. I separate the manuscript in four main parts. The first one presents an overview of supernovae from an observational and theoretical point of view. The second part describes the INTEGRAL satellite with its instruments, the techniques used for analyzing the data collected by IBIS/ISGRI, and my personal investigations concerning different developments such as: the spectral calibration of the IBIS/ISGRI instrument, the correction of noisy pixels on the camera, the creation of background maps, and the development of an alternative pipeline useful for dealing with a large amount of data. I also present a method for imaging extended sources with a coded-mask instrument such as IBIS/ISGRI, and its first application on the Coma Cluster. The results obtained on historical supernova remnants like Cas A, Tycho, RXJ0852-4622 (Vela Junior) are presented in the third part. The first chapter of the last part is devoted to the study of the detectability of supernovae in the optical domain with a model of the interstellar extinction. The second chapter reports on the search for missing and hidden young supernova remnants in the Milky Way with the IBIS/ISGRI galactic plane survey through the "4"4Sc gamma-ray lines as well as with a multi-wavelength approach, from the radio domain (VLA) to the new observational window at TeV energies (HESS). I also discuss the constraints on the supernova rate and the "4"4Ti production in core-collapse supernovae

  5. AN INDEPENDENT MEASUREMENT OF THE INCIDENCE OF Mg II ABSORBERS ALONG GAMMA-RAY BURST SIGHT LINES: THE END OF THE MYSTERY?

    International Nuclear Information System (INIS)

    Cucchiara, A.; Prochaska, J. X.; Zhu, G.; Ménard, B.; Fynbo, J. P. U.; Fox, D. B.; Chen, H.-W.; Cooksey, K. L.; Cenko, S. B.; Bloom, J. S.; Perley, D.; Berger, E.; Chornock, R.; Tanvir, N. R.; D'Elia, V.; Lopez, S.; De Jaeger, T.

    2013-01-01

    In 2006, Prochter et al. reported a statistically significant enhancement of very strong Mg II absorption systems intervening the sight lines to gamma-ray bursts (GRBs) relative to the incidence of such absorption along quasar sight lines. This counterintuitive result has inspired a diverse set of astrophysical explanations (e.g., dust, gravitational lensing) but none of these has obviously resolved the puzzle. Using the largest set of GRB afterglow spectra available, we reexamine the purported enhancement. In an independent sample of GRB spectra with a survey path three times larger than Prochter et al., we measure the incidence per unit redshift of ≥1 Å rest-frame equivalent width Mg II absorbers at z ≈ 1 to be l(z) = 0.18 ± 0.06. This is fully consistent with current estimates for the incidence of such absorbers along quasar sight lines. Therefore, we do not confirm the original enhancement and suggest those results suffered from a statistical fluke. Signatures of the original result do remain in our full sample (l(z) shows an ≈1.5 enhancement over l(z) QSO ), but the statistical significance now lies at ≈90% c.l. Restricting our analysis to the subset of high-resolution spectra of GRB afterglows (which overlaps substantially with Prochter et al.), we still reproduce a statistically significant enhancement of Mg II absorption. The reason for this excess, if real, is still unclear since there is no connection between the rapid afterglow follow-up process with echelle (or echellette) spectrographs and the detectability of strong Mg II doublets. Only a larger sample of such high-resolution data will shed some light on this matter

  6. Genomic prediction based on data from three layer lines using non-linear regression models.

    Science.gov (United States)

    Huang, Heyun; Windig, Jack J; Vereijken, Addie; Calus, Mario P L

    2014-11-06

    Most studies on genomic prediction with reference populations that include multiple lines or breeds have used linear models. Data heterogeneity due to using multiple populations may conflict with model assumptions used in linear regression methods. In an attempt to alleviate potential discrepancies between assumptions of linear models and multi-population data, two types of alternative models were used: (1) a multi-trait genomic best linear unbiased prediction (GBLUP) model that modelled trait by line combinations as separate but correlated traits and (2) non-linear models based on kernel learning. These models were compared to conventional linear models for genomic prediction for two lines of brown layer hens (B1 and B2) and one line of white hens (W1). The three lines each had 1004 to 1023 training and 238 to 240 validation animals. Prediction accuracy was evaluated by estimating the correlation between observed phenotypes and predicted breeding values. When the training dataset included only data from the evaluated line, non-linear models yielded at best a similar accuracy as linear models. In some cases, when adding a distantly related line, the linear models showed a slight decrease in performance, while non-linear models generally showed no change in accuracy. When only information from a closely related line was used for training, linear models and non-linear radial basis function (RBF) kernel models performed similarly. The multi-trait GBLUP model took advantage of the estimated genetic correlations between the lines. Combining linear and non-linear models improved the accuracy of multi-line genomic prediction. Linear models and non-linear RBF models performed very similarly for genomic prediction, despite the expectation that non-linear models could deal better with the heterogeneous multi-population data. This heterogeneity of the data can be overcome by modelling trait by line combinations as separate but correlated traits, which avoids the occasional

  7. Gamma ray emission from pulsars

    International Nuclear Information System (INIS)

    Salvati, M.; Massaro, E.

    1978-01-01

    A model for the production of gamma rays in a pulsar environment is presented, together with numerical computations fitted to the observations of PSR 0833-45. It is assumed that the primary particles are accelerated close to the star surface and then injected along the open field lines, which cause them to emit curvature radiation. The equation describing the particles' braking is integrated exactly up to the first order in the pulsar rotational frequency, and the transfer problem for the curvature photons is solved with the aberration, the Doppler shif, and the pair production absorption being taken into account. The latter effect is due not only to the transverse component of the magnetic field, but also to the electric field induced by the rotation. The synchrotron radiation emitted by the secondary particles is also included, subject to the 'on-the-spot' approximation. It is found that the observed gamma rays originate in the innermost regions of the magnetosphere, where the open lines' bundle is narrow and the geometrical beaming is effective. As shown by the computed pulse profiles, the duty cycle turns out to be equal to a few percent, comparable to the one of PSR 0833-45. The averaged spectra indicate that a substantial fraction of the primary photons do outlive the interaction with the magnetisphere; furthermore, the agreement in shape with the observational curves suggests that the acceleration output is fiarly close to a monoenergetic beam of particles. (orig.) [de

  8. Assembly and calibration of a new experimental apparatus for production and utilization of capture gamma rays

    International Nuclear Information System (INIS)

    Semmler, R.

    1993-01-01

    A new experimental apparatus has been mounted at the tangential beam tube B H 4/12 of the IPEN IEA-R1 (2 MW) reactor, for production and utilization of capture gamma rays. In this type of experiment, monochromatic gamma radiation, with energy resolution of about 10 eV, is produced by thermal neutron capture in several materials placed near the reactor core. By changing the target material it was possible to obtain up to 30 gamma lines in the 5 to 11 MeV energy range and so, the present experimental arrangement may be considered as an excellent gamma ray source for photonuclear reactions studies in low excitation energies. (author)

  9. An Overview of the Current Understanding of Gamma-Ray Bursts in the Fermi Era

    Science.gov (United States)

    Bhat, P. N.; Guiriec, Sylvain

    2011-01-01

    Gamma-ray bursts are the most luminous explosions in the Universe, and their origin as well as mechanism are the focus of intense research and debate. More than three decades since their serendipitous discovery, followed by several breakthroughs from space-borne and ground-based observations, they remain one of the most interesting astrophysical phenomena yet to be completely understood. Since the launch of Fermi with its unprecedented energy band width spanning seven decades, the study of gamma-ray burst research has entered a new phase. Here we review the current theoretical understanding and observational highlights of gamma-ray burst astronomy and point out some of the potential promises of multi-wavelength observations in view of the upcoming ground based observational facilities .

  10. Forward treatment planning techniques to reduce the normalization effect in Gamma Knife radiosurgery.

    Science.gov (United States)

    Cheng, Hao-Wen; Lo, Wei-Lun; Kuo, Chun-Yuan; Su, Yu-Kai; Tsai, Jo-Ting; Lin, Jia-Wei; Wang, Yu-Jen; Pan, David Hung-Chi

    2017-11-01

    In Gamma Knife forward treatment planning, normalization effect may be observed when multiple shots are used for treating large lesions. This effect can reduce the proportion of coverage of high-value isodose lines within targets. The aim of this study was to evaluate the performance of forward treatment planning techniques using the Leksell Gamma Knife for the normalization effect reduction. We adjusted the shot positions and weightings to optimize the dose distribution and reduce the overlap of high-value isodose lines from each shot, thereby mitigating the normalization effect during treatment planning. The new collimation system, Leksell Gamma Knife Perfexion, which contains eight movable sectors, provides an additional means to reduce the normalization effect by using composite shots. We propose different techniques in forward treatment planning that can reduce the normalization effect. Reducing the normalization effect increases the coverage proportion of higher isodose lines within targets, making the high-dose region within targets more uniform and increasing the mean dose to targets. Because of the increase in the mean dose to the target after reducing the normalization effect, we can set the prescribed marginal dose at a higher isodose level and reduce the maximum dose, thereby lowering the risk of complications. © 2017 Shuang Ho Hospital-Taipei Medical University. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

  11. Effect of gamma irradiation on the microstructure and post-mortem anaerobic metabolism of bovine muscle

    International Nuclear Information System (INIS)

    Yook, H.-S.; Lee, J.-W.; Lee, K.-H.; Kim, M.-K.; Song, C.-W.; Byun, M.-W.

    2001-01-01

    Experiments were performed to study the effect of gamma irradiation on morphological properties and post-mortem metabolism in bovine M. sternomandibularis with special reference to ultrastructure, shear force, pH and ATP breakdown. The shortening of sarcomere was not observed in gamma-irradiated muscle, however, the disappearance of M-line and of A- and I-bands was perceptible. During cold storage, the destruction of muscle bundles was faster in the gamma-irradiated muscle than in the non-irradiated with a dose-dependent manner. The same is true for the post mortem pH drop and ATP breakdown. So, experimental results confirmed that the anaerobic metabolism and morphological properties are noticeably affected by gamma irradiation in beef

  12. Dose Rate of Environmental Gamma Radiation in Java Island

    International Nuclear Information System (INIS)

    Gatot Suhariyono; Buchori; Dadong Iskandar

    2007-01-01

    The dose rate Monitoring of environmental gamma radiation at some locations in Java Island in the year 2005 / 2006 has been carried out. The dose rate measurement of gamma radiation is carried out by using the peripheral of Portable Gamma of Ray Spectrometer with detector of NaI(Tl), Merck Exploranium, Model GR-130- MINISPEC, while to determine its geographic position is used by the GPS (Global Positioning System), made in German corporation of GPS III Plus type. The division of measurement region was conducted by dividing Java Island become 66 parts with same distance, except in Jepara area that will built PLTN (Nuclear Energy Power), distance between measurement points is more closed. The results of dose rate measurement are in 66 locations in Java Island the range of (19.24 ± 4.05) nSv/hour until (150.78 ± 12.26) nSv/hour with mean (51.93 ± 36.53) nSv/h. The lowest dose rate was in location of Garut, while highest dose rate was in Ujung Lemah Abang, Jepara location. The data can be used for base line data of dose rate of environmental gamma radiation in Indonesia, specially in Java Island. The mean level of gamma radiation in Java monitoring area (0.46 mSv / year) was still lower than worldwide average effective dose rate of terrestrial gamma rays 0.5 mSv / year (report of UNSCEAR, 2000). (author)

  13. Many faces of compact objects: distance, optical extinction and multi-wavelength behaviour

    International Nuclear Information System (INIS)

    Corbel, Stephane

    1999-01-01

    This thesis is devoted to a multi-wavelength study of accretion-ejection phenomena around compact stars (black holes and neutron stars). The first part of this manuscript describes problems related to the determination of the distance and the optical extinction to compact objects - fundamental parameters for the evaluation of the energy budget of these systems. To this end, the structure and the dynamics of the Galaxy are studied by observations of the atomic and molecular gas along the line of sight to compact stars. This method leads to the first evaluation of the distance to two Soft Gamma Repeaters: SGR 1806-20 and SGR 1627-41. We then draw some conclusions on the nature of these sources of recurrent gamma-ray bursts. The above method is then applied to two X-ray binaries: Cir X-1 and GX 339-4. In the second part of this thesis, we present a multi-wavelength study of the Galactic black hole candidate GX 339-4. We first discuss the characteristics of the radio emission from GX 339-4. In 1998, GX 339-4 underwent a transition to a soft-high X-ray state and observations in three wavelength regimes (radio, soft and hard X-rays) revealed new patterns of behaviour. This allowed us to constrain the region of origin of the radio emission (a compact jet) in GX 339-4 and allowed a better understanding of the physical coupling between accretion and ejection in GX 339-4. An analogy with the black hole candidate Cyg X-1 is then presented. Finally, these results are discussed in the context of micro-quasars and active galactic nuclei in order to gain a deeper insight into the accretion-ejection coupling around compact objects. (author) [fr

  14. Determination of gamma radiation lethal dose (LD{sub 50}) and resveratrol cytotoxicity level in tumor cells line

    Energy Technology Data Exchange (ETDEWEB)

    Magalhaes, Vanessa D.; Rogero, Sizue O.; Rogero, Jose R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Cruz, Aurea S. [Instituto Adolfo Lutz (IAL-SP) Secao de Culturas Celulares, SP (Brazil)

    2011-07-01

    Cancer is a disease with high incidence and it is considered a worldwide public health problem. Resveratrol is a polyphenol occurring naturally in a wide variety of plants according to response of ultraviolet radiation (UV) exposition or according to mechanical stress resulting of pathogens or chemical and physical agents. This polyphenol possesses a pharmacological activity of carcinogenesis inhibition in multiple levels. It also protects cells by scavenging the free radicals which are considered toxic products. These free radicals are formed of natural process of cell aging and also by incidence of ionizing radiation in the organism. Thus, resveratrol is considered as a cell radioprotector. On the other hand, in some elevated concentrations resveratrol may be considered as a radiosensitizing. The aim of this work was the determination of radiation lethal dose (LD{sub 50}) and also verifies the cytotoxicity level of resveratrol in tumor cells line: muco epidermoid pulmonary carcinoma cells (NCI-H292) and rhabdomyosarcoma cells (RD). The cytotoxicity test was performed by neutral red uptake assay. The results of resveratrol IC{sub 50%} in NCI-H292 cells was 192{mu}M and in RD cells was 128{mu}M; and RD cells gamma radiation LD{sub 50} was 435Gy. (author)

  15. Measurement of neutron and gamma-ray production double differential cross section at KEK

    International Nuclear Information System (INIS)

    Ishibashi, Kenji

    1995-01-01

    High energy nuclear radiations were measured for 0.8-3.0 GeV proton induced reactions at KEK. The measurement was carried out to overcome the problems arising from the use of secondary beam line of a quite low incident beam intensity. Digital pulse shape discrimination method was applicable to separation between high energy neutrons and gamma-rays. By the use of a number of scintillators, cross sections were obtained for production of neutrons and gamma-rays. (author)

  16. Einstein@Home discovers a radio-quiet gamma-ray millisecond pulsar

    Science.gov (United States)

    Clark, Colin J.; Pletsch, Holger J.; Wu, Jason; Guillemot, Lucas; Kerr, Matthew; Johnson, Tyrel J.; Camilo, Fernando; Salvetti, David; Allen, Bruce; Anderson, David; Aulbert, Carsten; Beer, Christian; Bock, Oliver; Cuéllar, Andres; Eggenstein, Heinz-Bernd; Fehrmann, Henning; Kramer, Michael; Kwang, Shawn A.; Machenschalk, Bernd; Nieder, Lars; Ackermann, Markus; Ajello, Marco; Baldini, Luca; Ballet, Jean; Barbiellini, Guido; Bastieri, Denis; Bellazzini, Ronaldo; Bissaldi, Elisabetta; Blandford, Roger D.; Bloom, Elliott D.; Bonino, Raffaella; Bottacini, Eugenio; Brandt, Terri J.; Bregeon, Johan; Bruel, Philippe; Buehler, Rolf; Burnett, Toby H.; Buson, Sara; Cameron, Rob A.; Caputo, Regina; Caraveo, Patrizia A.; Cavazzuti, Elisabetta; Cecchi, Claudia; Charles, Eric; Chekhtman, Alexandre; Ciprini, Stefano; Cominsky, Lynn R.; Costantin, Denise; Cutini, Sara; D’Ammando, Filippo; De Luca, Andrea; Desiante, Rachele; Di Venere, Leonardo; Di Mauro, Mattia; Di Lalla, Niccolò; Digel, Seth W.; Favuzzi, Cecilia; Ferrara, Elizabeth C.; Franckowiak, Anna; Fukazawa, Yasushi; Funk, Stefan; Fusco, Piergiorgio; Gargano, Fabio; Gasparrini, Dario; Giglietto, Nico; Giordano, Francesco; Giroletti, Marcello; Gomez-Vargas, Germán A.; Green, David; Grenier, Isabelle A.; Guiriec, Sylvain; Harding, Alice K.; Hewitt, John W.; Horan, Deirdre; Jóhannesson, Guðlaugur; Kensei, Shiki; Kuss, Michael; La Mura, Giovanni; Larsson, Stefan; Latronico, Luca; Li, Jian; Longo, Francesco; Loparco, Francesco; Lovellette, Michael N.; Lubrano, Pasquale; Magill, Jeffrey D.; Maldera, Simone; Manfreda, Alberto; Mazziotta, Mario N.; McEnery, Julie E.; Michelson, Peter F.; Mirabal, Nestor; Mitthumsiri, Warit; Mizuno, Tsunefumi; Monzani, Maria Elena; Morselli, Aldo; Moskalenko, Igor V.; Nuss, Eric; Ohsugi, Takashi; Omodei, Nicola; Orienti, Monica; Orlando, Elena; Palatiello, Michele; Paliya, Vaidehi S.; de Palma, Francesco; Paneque, David; Perkins, Jeremy S.; Persic, Massimo; Pesce-Rollins, Melissa; Porter, Troy A.; Principe, Giacomo; Rainò, Silvia; Rando, Riccardo; Ray, Paul S.; Razzano, Massimiliano; Reimer, Anita; Reimer, Olaf; Romani, Roger W.; Saz Parkinson, Pablo M.; Sgrò, Carmelo; Siskind, Eric J.; Smith, David A.; Spada, Francesca; Spandre, Gloria; Spinelli, Paolo; Thayer, Jana B.; Thompson, David J.; Torres, Diego F.; Troja, Eleonora; Vianello, Giacomo; Wood, Kent; Wood, Matthew

    2018-01-01

    Millisecond pulsars (MSPs) are old neutron stars that spin hundreds of times per second and appear to pulsate as their emission beams cross our line of sight. To date, radio pulsations have been detected from all rotation-powered MSPs. In an attempt to discover radio-quiet gamma-ray MSPs, we used the aggregated power from the computers of tens of thousands of volunteers participating in the Einstein@Home distributed computing project to search for pulsations from unidentified gamma-ray sources in Fermi Large Area Telescope data. This survey discovered two isolated MSPs, one of which is the only known rotation-powered MSP to remain undetected in radio observations. These gamma-ray MSPs were discovered in completely blind searches without prior constraints from other observations, raising hopes for detecting MSPs from a predicted Galactic bulge population. PMID:29503868

  17. Development of ultrahigh energy resolution gamma spectrometers for nuclear safeguards

    International Nuclear Information System (INIS)

    Drury, O.B.; Velazquez, M.; Dreyer, J.G.; Friedrich, S.

    2009-01-01

    We are developing superconducting ultrahigh resolution gamma-detectors for non-destructive analysis (NDA) of nuclear materials, and specifically for spent fuel characterization in nuclear safeguards. The detectors offer an energy resolution below 100 eV FWHM at 100 keV, and can therefore significantly increase the precision of NDA at low energies where line overlap affects the errors of the measurement when using germanium detectors. They also increase the peak-to-background ratio and thus improve the detection limits for weak gamma emissions from the fissile Pu and U isotopes at low energy in the presence of an intense Compton background from the fission products in spent fuel. Here we demonstrate high energy resolution and high peak-to-background ratio of our superconducting Gamma detectors, and discuss their relevance for measuring actinides in spent nuclear fuel. (author)

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

    International Nuclear Information System (INIS)

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

    2013-01-01

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

  19. Observing broad-absorption line quasars with Spectrum-Rontgen-Gamma

    DEFF Research Database (Denmark)

    Singh, K.P.; Schnopper, H.W.; Westergaard, Niels Jørgen Stenfeldt

    1998-01-01

    Broad-absorption line quasars are found to have extremely weak soft X-ray emission when compared with other optically selected quasars. In the only example of PHL 5200 for which a detailed X-ray spectrum has been obtained with ASCA, strong absorption in the source appears to be responsible...

  20. Multichannel CdZnTe Gamma Ray Spectrometer

    International Nuclear Information System (INIS)

    Doty, F.P.; Lingren, C. L.; Apotovsky, B. A.; Brunsch, J.; Butler, J. F.; Collins, T.; Conwell, R.L.; Friesenhahn, S.; Gormley, J.; Pi, B.; Zhao, S.; Augustine, F.L.; Bennet, B. A.; Cross, E.; James, R. B.

    1998-01-01

    A 3 cm 3 multichannel gamma spectrometer for DOE applications is under development by Digirad Corporation. The device is based on a position sensitive detector packaged in a compact multi-chip module (MCM) with integrated readout circuitry. The modular, multichannel design will enable identification and quantitative analysis of radionuclides in extended sources, or sources containing low levels of activity. The MCM approach has the advantages that the modules are designed for imaging applications, and the sensitivity can be arbitrarily increased by increasing the number of pixels, i.e. adding modules to the instrument. For a high sensitivity probe, the outputs for each pixel can be corrected for gain and offset variations, and summed digitally. Single pixel results obtained with discrete low noise readout indicate energy resolution of 3 keV can be approached with currently available CdZnTe. The energy resolution demonstrated to date with MCMs for 511 keV gamma rays is 10 keV