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Sample records for proton-induced spallation reactions

  1. Investigation of GeV proton-induced spallation reactions

    International Nuclear Information System (INIS)

    Hilscher, D.; Herbach, C.-M.; Jahnke, U.

    2003-01-01

    A reliable and precise modeling of GeV proton-induced spallation reactions is indispensable for the design of the spallation module and the target station of future accelerator driven hybrid reactors (ADS) or spallation neutron sources (ESS), in particular, to provide precise predictions for the neutron production, the radiation damage of materials (window), and the production of radioactivity ( 3 H, 7 Be etc.) in the target medium. Detailed experimental nuclear data are needed for sensitive validations and improvements of the models, whose predictive power is strongly dependent on the correct physical description of the three main stages of a spallation reaction: (i) the Intra-Nuclear-Cascade (INC) with the fast heating of the target nucleus, (ii) the de-excitation due to pre-equilibrium emission including the possibility of multi-fragmentation, and (iii) the statistical decay of thermally excited nuclei by evaporation of light particles and fission in the case of heavy nuclei. Key experimental data for this endeavour are absolute production cross sections and energy spectra for neutrons and light charged-particles (LCPs), emission of composite particles prior and post to the attainment of an equilibrated system, distribution of excitation energies deposited in the nuclei after the INC, and fission probabilities. The correlations of these quantities are particularly important to detect and identify possible deficiencies of the theoretical modeling of the various stages of a spallation reaction. Systematic measurements of such data are furthermore needed over large ranges of target nuclei and incident proton energies. Such data has been measured with the NESSI detector. An overview of new and previous results will be given. (authors)

  2. Fragment mass distribution of proton-induced spallation reaction with intermediate energy

    International Nuclear Information System (INIS)

    Fan Sheng; Ye Yanlin; Xu Chuncheng; Chen Tao; Sobolevsky, N.M.

    2000-01-01

    The test of part benchmark of SHIELD code is finished. The fragment cross section and mass distribution and excitation function of the residual nuclei from proton-induced spallation reaction on thin Pb target with intermediate energy have been calculated by SHIELD code. And the results are in good agreement with measured data. The fragment mass distribution of the residual nuclei from proton-induced spallation reaction on thick Pb target with incident energy 1.6 GeV have been simulated

  3. The future plan for the applications of RI produced in the proton-induced spallation-reaction

    Energy Technology Data Exchange (ETDEWEB)

    Ikezoe, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-07-01

    A plan of research facilities (transmutations of minor actinides and neutron scattering for material and life sciences) has been proposed in JAERI. This plan is based on a proton lineac with an energy of 1.5 GeV and a beam current of several mA. Among these facilities, we are planning to accelerate neutron-rich radioactive nuclei (RI) produced in the fission and spallation reactions of thorium or uranium bombarded by the intense high energy proton beams. The RI produced in an ion source are separated by a high resolution isotope separator and their charge states are changed to be negative to inject into the existing tandem-booster accelerator. Main purpose of this plan is to study the nuclear and chemical properties of neutron rich transactinium elements not yet synthesized and the nuclear structures of neutron rich nuclei far from the nuclear stability line. (author)

  4. Spallation reactions; Reactions de spallation

    Energy Technology Data Exchange (ETDEWEB)

    Cugon, J.

    1996-12-31

    Spallation reactions dominate the interactions of hadrons with nuclei in the GeV range (from {approx} 0.1 to {approx} 10 GeV). They correspond to a sometimes important ejection of light particles leaving most of the time a residue of mass commensurate with the target mass. The main features of the experimental data are briefly reviewed. The most successful theoretical model, namely the intranuclear cascade + evaporation model, is presented. Its physical content, results and possible improvements are critically discussed. Alternative approaches are shortly reviewed. (author). 84 refs.

  5. Helium production for 0.8-2.5 GeV proton induced spallation reactions, damage induced in metallic window materials

    International Nuclear Information System (INIS)

    Hilscher, D.; Herbach, C.-M.; Jahnke, U.; Tishchenko, V.; Enke, M.; Filges, D.; Goldenbaum, F.; Neef, R.-D.; Nuenighoff, K.; Paul, N.; Schaal, H.; Sterzenbach, G.; Letourneau, A.; Boehm, A.; Galin, J.; Lott, B.; Peghaire, A.; Pienkowski, L.

    2001-01-01

    Production cross-sections for neutrons and charged particles as well as excitation energy distributions in spallation reactions were measured recently by the NESSI-collaboration and have been employed to test different intra nuclear cascade models and the subsequent evaporation. The INCL/GEMINI code, which describes best the experimental data has been employed to calculate the damage cross-sections in Fe and Ta as well as the He/dpa ratio as a function of proton energy. For the same amount of neutron production in a typical target of a spallation neutron source the proton beam induced radiation damage in an Fe window is shown to decrease almost linearly with proton energy. For heavier materials such as Ta a similar decrease of the radiation damage is found only for energies above about 3 GeV

  6. Spallation reactions: calculations

    International Nuclear Information System (INIS)

    Bertini, H.W.

    1975-01-01

    Current methods for calculating spallation reactions over various energy ranges are described and evaluated. Recent semiempirical fits to existing data will probably yield the most accurate predictions for these reactions in general. However, if the products in question have binding energies appreciably different from their isotropic neighbors and if the cross section is approximately 30 mb or larger, then the intranuclear-cascade-evaporation approach is probably better suited. (6 tables, 12 figures, 34 references) (U.S.)

  7. Analysis for mass distribution of proton-induced reactions in intermediate energy range

    CERN Document Server

    Xiao Yu Heng

    2002-01-01

    The mass and charge distribution of residual products produced in the spallation reactions needs to be studied, because it can provide useful information for the disposal of nuclear waste and residual radioactivity generated by the spallation neutron target system. In present work, the Many State Dynamical Model (MSDM) is based on the Cascade-Exciton Model (CEM). The authors use it to investigate the mass distribution of Nb, Au and Pb proton-induced reactions in energy range from 100 MeV to 3 GeV. The agreement between the MSDM simulations and the measured data is good in this energy range, and deviations mainly show up in the mass range of 90 - 150 for the high energy proton incident upon Au and Pb

  8. Analysis for fragmentation products of proton-induced reactions on Pb with energy up to GeV

    International Nuclear Information System (INIS)

    Fan Sheng; Li Zhuxia; Zhao Zhixiang; Ding Dazhao

    2002-01-01

    The mass and charge distribution of residual products produced in the spallation reaction needs to be studied because it can provide useful information for the disposal of nuclear and the radiation damage in the spallation target. The mass and charge distribution of the spallation products is studied by using quantum molecular dynamic (QMD) models. The simulation results are well agreed with the experimental data of the spallation fragment and empirical formula. However, QMD model does not include the fission process; the calculations can not reproduce the fission fragment. The fission model is introduced into QMD model to investigate the fragment products from proton-induced reactions on Pb. The results are in good agreement with the experimental data

  9. Photonuclear spallation reactions in Cu

    International Nuclear Information System (INIS)

    Shibata, S.; Imamura, M.; Miyachi, T.

    1986-06-01

    Formation yields of 24 radioactive nuclides by the interaction of bremsstrahlung in the maximum end-point energies of 100 MeV - 1 GeV with Cu have been measured by direct γ-ray counting of irradiated targets. The yields in the mass range of 42 to 60 except for 60 Cu were analysed by non-linear least-squares fit to construct the mass yield and charge dispersion curves in spallation reactions. From the parameter values obtained, the energy dependence of the slope of the mass yield curve and the relationship between target N/Z and the most probable product N/Z were investigated in comparison with the results of proton, α and heavy ion-induced spallations of Cu. The characteristics of photon-induced spallations are discussed. (author)

  10. Spallation reactions - physics and applications

    International Nuclear Information System (INIS)

    Kelic, A.; Ricciardi, M.; Schmidt, K-H.

    2009-01-01

    Spallation reactions have become an ideal tool for studying the equation of state and thermal instabilities of nuclear matter. In astrophysics, the interactions of cosmic rays with the interstellar medium have to be understood in detail for deducing their original composition and their production mechanisms. Renewed interest in spallation reactions with protons around 1 GeV came up recently with the developments of spallation neutron sources. The project of an accelerator-driven system (ADS) as a technological solution for incinerating the radioactive waste even intensified the efforts for better understanding the physics involved in the spallation process. Experiments on spallation reactions were performed for determining the production cross sections and properties of particles, fragments and heavy residues. Traditional experiments on heavy residues, performed in direct kinematics, were limited to the direct observation of long-lived radioactive nuclides and did not provide detailed information on the kinematics of the reaction. Therefore, an innovative experimental method has been developed, based on inverse kinematics, which allowed to identify all reaction residues in-flight, using the high resolution magnetic spectrometer FRS of GSL Darmstadt. It also gives direct access to the reaction kinematics. An experimental campaign has been carried out in a Europe-wide collaboration, investigating the spallation of several nuclei ranging from 56 Fe to 238 U Complementary experiments were performed with a full-acceptance detection system, yielding total fission cross sections. Recently, another detection system using the large acceptance ALADIN dipole and the LAND neutron detector was introduced to measure light particles in coincidence with the heavy residues. Another intense activity was dedicated to developing codes, which cover nuclear reactions occurring in an ADS. The first phase of the reaction is successfully described by a sequence of quasi-free nucleon

  11. Spallation reactions studied with 4-detector arrays

    Indian Academy of Sciences (India)

    Recently there has been a renewed interest in the study of spallation reactions in basic nuclear physics as well as in potential applications. Spallation reactions induced by light projectiles (protons, antiprotons, pions, etc.) in the GeV range allow the formation of hot nuclei which do not suffer the collective excitations ...

  12. A sistematical study of spallation reaction

    International Nuclear Information System (INIS)

    Foshina, M.

    1982-01-01

    A four-parameter semi-empirical formulae is proposed to calculate photo-spallation cross sections. This formulae is deduced starting from a nuclear model considered as a particle mixture without differences among them and the spallation phenomenous is considered as sucessive nucleon emission ruled by determined probability law. The formulae parameters are obtained from photo-spallation yields experimentally determined and available in literature. A variation study of the values of different parameters with the mass number of the 'seed' nucleus and incident energy is made. A parallel study for the spallation reactions induced by protons of a sampling of 720 data is also presented. (L.C.) [pt

  13. Production of Actinium-225 via High Energy Proton Induced Spallation of Thorium-232

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, James T.; Nolen, Jerry; Vandergrift, George; Gomes, Itacil; Kroc, Tom; Horwitz, Phil; McAlister, Dan; Bowers, Del; Sullivan, Vivian; Greene, John

    2011-12-30

    The science of cancer research is currently expanding its use of alpha particle emitting radioisotopes. Coupled with the discovery and proliferation of molecular species that seek out and attach to tumors, new therapy and diagnostics are being developed to enhance the treatment of cancer and other diseases. This latest technology is commonly referred to as Alpha Immunotherapy (AIT). Actinium-225/Bismuth-213 is a parent/daughter alpha-emitting radioisotope pair that is highly sought after because of the potential for treating numerous diseases and its ability to be chemically compatible with many known and widely used carrier molecules (such as monoclonal antibodies and proteins/peptides). Unfortunately, the worldwide supply of actinium-225 is limited to about 1,000mCi annually and most of that is currently spoken for, thus limiting the ability of this radioisotope pair to enter into research and subsequently clinical trials. The route proposed herein utilizes high energy protons to produce actinium-225 via spallation of a thorium-232 target. As part of previous R and D efforts carried out at Argonne National Laboratory recently in support of the proposed US FRIB facility, it was shown that a very effective production mechanism for actinium-225 is spallation of thorium-232 by high energy proton beams. The base-line simulation for the production rate of actinium-225 by this reaction mechanism is 8E12 atoms per second at 200 MeV proton beam energy with 50 g/cm2 thorium target and 100 kW beam power. An irradiation of one actinium-225 half-life (10 days) produces {approx}100 Ci of actinium-225. For a given beam current the reaction cross section increases slightly with energy to about 400 MeV and then decreases slightly for beam energies in the several GeV regime. The object of this effort is to refine the simulations at proton beam energies of 400 MeV and above up to about 8 GeV. Once completed, the simulations will be experimentally verified using 400 MeV and 8 Ge

  14. Cross-sections of spallation residues produced in Proton –Induced reactions

    International Nuclear Information System (INIS)

    Al-Haydari, A.; Khan, A.A.; Abdul Ganai, A.; Hassan, G.S.

    2013-01-01

    The recent available GSI data for proton-induced spallation reactions by using inverse kinematics at different energies are analyzed for different reactions in terms of the percolation model together with the intranuclear cascade model (MCAS). The simulation results obtained for the cross sections of production of light ions and isotopes as a function of mass and charge number is calculated. Results of calculations are in good agreement with experiment

  15. Production of noble gas isotopes by proton-induced reactions on bismuth

    International Nuclear Information System (INIS)

    Leya, I.; David, J.-C.; Leray, S.; Wieler, R.; Michel, R.

    2008-01-01

    We measured integral thin target cross sections for the proton-induced production of He-, Ne-, Ar-, Kr- and Xe-isotopes from bismuth (Bi) from the respective reaction thresholds up to 2.6 GeV. Here we present 275 cross sections for 23 nuclear reactions. The production of noble gas isotopes from Bi is of special importance for design studies of accelerator driven systems (EA/ADS) and nuclear spallation sources. For experiments with proton energies above 200 MeV the mini-stack approach was used instead of the stacked-foil technique in order to minimise the influences of secondary particles on the residual nuclide production. Comparing the cross sections for Bi to the data published recently for Pb indicates that for 4 He the cross sections for Bi below 200 MeV are up to a factor of 2-3 higher than the Pb data, which can be explained by the production of α-decaying Po-isotopes from Bi but not from Pb. Some of the cross sections for the production of 21 Ne from Bi are affected by recoil effects from neighboured Al-foils, which compromises a study of a possible lowering of the effective Coulomb-barrier. The differences in the excitation functions between Pb and Bi for Kr- and Xe-isotopes can be explained by energy-dependent higher fission cross sections for Bi compared to Pb. The experimental data are compared to results from the theoretical nuclear model codes INCL4/ABLA and TALYS. The INCL4/ABLA system describes the cross sections for the production of 4 He-, Kr- and Xe-isotopes reasonably well, i.e. mostly within a factor of a few. In contrast, the model completely fails describing 21 Ne, 22 Ne, 36 Ar and 38 Ar, which are produced via spallation and/or multifragmentation. The TALYS code is only able to accurately predict reaction thresholds. The absolute values are either significantly over- or underestimated. Consequently, the comparison of measured and modelled thin target cross sections clearly indicates that experimental data are still needed because the

  16. Nucleon and composite-particle production in spallation reactions studied with the multi-purpose detector NESSI

    International Nuclear Information System (INIS)

    Herbach, C.M.; Hilscher, D.; Jahnke, U.; Tishchenko, V.G.; Galin, J.; Lott, B.; Letourneau, A.; Peghaire, A.; Filges, D.; Goldenbaum, F.; Nuenighoff, K.; Schaal, H.; Sterzenbach, G.; Wohlmuther, M.; Pienkowski, L.; Kostecke, D.; Schroeder, W.U.; Toke, J.

    2003-01-01

    NESSI, a 4π-detector for neutrons and charged particles, was used in studies of proton-induced spallation reactions at the COSY facility. Due to the high detection efficiency of NESSI for particles evaporated from excited nuclei, measured particle multiplicities provide event-by-event information on the nuclear excitation energy. Data obtained for proton-induced reactions on thin targets ranging from Al to U and proton energies from 0.8 to 2.5 GeV are compared with model predictions. (orig.)

  17. Production of residual nuclides by proton-induced reactions on target W at the energy of 72 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Miah, Moazzem Hossain [Univ. of Chittagong, Dept. of Physics, Chittagong (Bangladesh); Kuhnhenn, Jochen; Herpers, Ulrich [Univ. of Cologne, Dept. of Nuclear Chemistry, Cologne (Germany); Michel, Rolf [University of Hannover, Centre for Radiation Protection and Radioecology (Germany); Kubik, Peter [Paul Scherrer Inst., c/o Institute for Particle Physics, ETH Hoenggerberg, Zuerich (Switzerland)

    2002-08-01

    Investigations of cross-sections for residual nuclide production on the target element W by proton-induced reactions were performed by irradiating the target with 72 MeV protons using the cyclotron facilities at Paul-Scherrer Institute, Zurich, Switzerland. Residual nuclides were measured by gamma-spectrometry of HpGe detectors calibrated with standard gamma sources. The measured data contains 104 individual cross-sections for 20 identified nuclides in the proton energies between 52.5 - 68.9 MeV. These nuclear data is important in the study of spallation neutron source and in accelerator driven technologies such as waste transmutation and energy amplification. The present data are compared with the shape of the excitation functions of earlier only one measurement at higher energies and they are in good agreement to each other. (author)

  18. Differential production cross sections of multiply charged fragments in 800 MeV proton-induced spallation of carbon, aluminum, and nickel

    International Nuclear Information System (INIS)

    Luckstead, S.C.

    1978-09-01

    Differential production cross sections for multiply charged fragments from 800-MeV proton-induced spallation of 12 C, 27 Al, and natural Ni were measured at 30 and 90 degrees. The ion fragments were identified by use of time-of-flight, ΔE--E detector telescope capable of complete particle identification for energies as low as .25 MeV/nucleon. The very short ranges of the particles of interest required the construction of very thin detectors with minimal deadlayer material. The time-pick-off detectors and gas ionization chamber developed are unique, and represent the state-of-the-art in fast timing for time-of-flight measurements and in construction of thin detectors. The resolutions achieved allowed the cross sections of 3 He, 4 He, 6 Li, 7 Li, 7 Be, 9 Be, 10 Be, 10 B, 11 B, 11 C, 12 C, and 13 C to be determined, along with those of nitrogen and oxygen without isotope separation. The cross sections were found to have weak angular dependence. Consequently, pseudo cross sections were calculated from the 90 0 data by integrating the differential cross sections from 0 to 25 MeV for each product and multiplying by 4π. Pseudo theoretical cross sections were similarly calculated from theoretical differential cross sections. These differential cross sections were calculated by use of a Monte Carlo computer code which incorporated the cascade-evaporation model of high-energy nuclear reactions. Implications are drawn for modifications of the model. The results suggest reducing the transparency of the struck nucleus to pions produced in the cascade stage of the reaction model in order that a higher excitation energy be left for the evaporation stage. Also, there is some evidence that evaporations of nuclear aggregates more massive than 4 He occur. Inclusion of such evaporations should improve the model. 82 figures, 1 table

  19. Status of experimental data of proton-induced reactions for intermediate-energy nuclear data evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Yukinobu; Kawano, Toshihiko [Kyushu Univ., Fukuoka (Japan); Yamano, Naoki; Fukahori, Tokio

    1998-11-01

    The present status of experimental data of proton-induced reactions is reviewed, with particular attention to total reaction cross section, elastic and inelastic scattering cross section, double-differential particle production cross section, isotope production cross section, and activation cross section. (author)

  20. Light nuclides produced in the proton-induced spallation of {sup 238}U at 1 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Ricciardi, M.V.; Armbruster, P. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Benlliure, J. [Universidad de Santiago de Compostela (ES)] [and others

    2005-09-01

    The production of light and intermediate-mass nuclides formed in the reaction {sup 1}H+{sup 238}U at 1 GeV was measured at the fragment separator (FRS) at GSI, Darmstadt. The experiment was performed in inverse kinematics, shooting a 1 A GeV {sup 238}U beam on a thin liquid-hydrogen target. 254 isotopes of all elements in the range 7{<=}Z{<=}37 were unambiguously identified, and the velocity distributions of the produced nuclides were determined with high precision. The results show that the nuclides are produced in a very asymmetric binary decay of heavy nuclei originating from the spallation of uranium. All the features of the produced nuclides merge with the characteristics of the fission products as their mass increases. (orig.)

  1. Multi-criteria comparative evaluation of spallation reaction models

    Science.gov (United States)

    Andrianov, Andrey; Andrianova, Olga; Konobeev, Alexandr; Korovin, Yury; Kuptsov, Ilya

    2017-09-01

    This paper presents an approach to a comparative evaluation of the predictive ability of spallation reaction models based on widely used, well-proven multiple-criteria decision analysis methods (MAVT/MAUT, AHP, TOPSIS, PROMETHEE) and the results of such a comparison for 17 spallation reaction models in the presence of the interaction of high-energy protons with natPb.

  2. Production cross sections of proton-induced reactions on yttrium

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Sung-Chul; Song, Tae-Yung; Lee, Young-Ouk [Nuclear Data Center, Korea Atomic Energy Research Institute, Daejeon 34057 (Korea, Republic of); Kim, Guinyun, E-mail: gnkim@knu.ac.kr [Department of Physics, Kyungpook National University, Daegu 41566 (Korea, Republic of)

    2017-05-01

    The production cross sections of residual radionuclides such as {sup 86,88,89g}Zr, {sup 86g,87m,87g,88}Y, {sup 83g,85g}Sr, and {sup 83,84g}Rb in the {sup 89}Y(p,x) reaction were measured using a stacked-foil activation and offline γ-ray spectrometric technique with proton energies of 57 MeV and 69 MeV at the 100 MeV proton linac in the Korea Multi-purpose Accelerator Complex (KOMAC), Gyeongju, Korea. The induced activities of the activated samples were measured using a high purity germanium (HPGe) detector, and the proton flux was determined using the {sup nat}Cu(p,x){sup 62}Zn reaction. The measured data was compared with other experimental data and the data from the TENLD-2015 library based on the TALYS code. The present results are generally lower than those in literature, but are found to be in agreement with the shape of the excitation functions. The integral yields for the thick target using the measured cross sections are given.

  3. Proton induced nuclear reactions on natural antimony up to 17 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Elbinawi, Alaa; Al-abyad, Mogahed; Hassan, Khaled F. [Atomic Energy Authority, Cairo (Egypt). Cyclotron Facility; Abd-Elmageed, Karima E. [Benha Univ. (Egypt). Dept. of Physics; Ditroi, Ferenc [Hungarian Academy of Sciences, Debrecen (Hungary). Inst. for Nuclear Research (ATOMKI)

    2016-08-01

    The activation cross sections of proton induced reactions on {sup nat}Sb target leading to the formation of the radioisotopes {sup 121m,g,123m}Te were measured. The experimental excitation functions were compared with the theoretical model calculations using the codes EMPIRE-3.1 and TALYS-1.4. The integral yields of the three radionuclides were calculated and the possibility of their production is discussed.

  4. Experimental cross-sections for proton-induced nuclear reactions on Mo-nat

    Czech Academy of Sciences Publication Activity Database

    Červenák, Jaroslav; Lebeda, Ondřej

    2016-01-01

    Roč. 380, AUG (2016), s. 32-49 ISSN 0168-583X R&D Projects: GA MŠk(CZ) LM2011019 Institutional support: RVO:61389005 Keywords : cross-sections * excitation functions * proton-induced nuclear reactions * natural molybdenum * Mo-99 * Tc-99m * Tc96m+g * Tc-95m * thick target yields * U-120M cyclotron Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.109, year: 2016

  5. Mass formula dependence of calculated spallation reaction product distributions

    International Nuclear Information System (INIS)

    Nishida, Takahiko; Nakahara, Yasuaki

    1990-01-01

    A new version of the spallation reaction simulation code NUCLEUS was developed by incorporating Uno and Yamada's mass formula. This version was used to calculate the distribution of products from the spallation of uranium nuclei by high-energy protons. The dependence of the distributions on the mass formula was examined by comparing the results with those from the original version, which is based on Cameron's mass formula and the mass table compiled by Wapstra et al. As regards the fission component of spallation products, the new version reproduces the reaction product data obtained from thin foil experiments much better, especially on the neutron excess side. (orig.) [de

  6. Remeasurement and compilation of excitation function of proton induced reactions on iron for activation techniques

    International Nuclear Information System (INIS)

    Takacs, S.; Vasvary, L.; Tarkanyi, F.

    1994-01-01

    Excitation functions of proton induced reactions on nat Fe(p, xn) 56 Co have been remeasured in the energy region up to 18 MeV using stacked foil technique and standard high resolution gamma-ray spectrometry at the Debrecen MGC-20E cyclotron. Compilation of the available data measured between 1959 and 1993 has been made. The corresponding excitation functions have been reviewed, critical comparison of all the available data was done to obtain the most accurate data set. The feasibility of the evaluated data set was checked by reproducing experimental calibration curves for TLA by calculation. (orig.)

  7. Proton induced nuclear reactions on cadmium up 17 MeV

    International Nuclear Information System (INIS)

    Al-Abyad, M.

    2012-01-01

    The cross-sections of proton induced reactions on nat Cd targets was studied in the energy range from threshold up to 17 MeV, using a stacked-foil irradiation technique and classical gamma-spectroscopy. We measured the formation cross-sections of the radioisotopes 109g,110m,110,111g,113m,114m,115m,116m In The obtained excitation functions were compared with the earlier published data and the theoretical model calculations by the codes ALICE-IPPE, EMPIRE and TALYS .

  8. From the HINDAS Project: Excitation Functions for Residual Nuclide Production by Proton-Induced Reactions

    International Nuclear Information System (INIS)

    Michel, R.; Gloris, M.; Protoschill, J.; Uosif, M.A.M.; Weug, M.; Herpers, U.; Kuhnhenn, J.; Kubik, P.-W.; Schumann, D.; Synal, H.-A.; Weinreich, R.; Leya, I.; David, J.C.; Leray, S.; Duijvestijn, M.; Koning, A.; Kelic, A.; Schmidt, K.H.; Cugnon, J.

    2005-01-01

    A survey is given about efforts undertaken during the HINDAS project to investigate the energy dependence of residual nuclide production by proton-induced reactions from thresholds up to 2.6 GeV. For proton-induced reactions, our experiments aimed to further develop and complete the cross-section database that was established by our collaboration in recent years. It was extended to the heavy-target elements Ta, W, Pb, and Bi for energies up to 2.6 GeV. In addition, new measurements for the target element iron were performed up to 2.6 GeV and for natural uranium for energies from 21 MeV to 69 MeV. For the target element lead, a comprehensive set of excitation functions published recently was completed by AMS-measurements of cross sections for the production of the long-lived radionuclides Be-10, Al-26, Cl-36, and I-129 and by mass spectrometric measurements for stable and radioactive rare gas isotopes of He, Ne, Ar, Kr, and Xe. Comprehensive tests of the nuclear-reaction codes TALYS and INCL4+ABLA, which were developed within the HINDAS project, were performed with the new experimental results over the entire energy range

  9. Validation of MC models of spallation reactions in thin and thick targets in the GeV range

    International Nuclear Information System (INIS)

    Goldenbaum, F.; Filges, D.; Neef, R.D.; Nuenighoff, K.; Paul, N.; Schaal, H.; Sterzenbach, G.; Tietze, A.; Wohlmuther, M.; Galin, J.; Letourneau, A.; Lott, B.; Peghaire, A.; Pienkowski, L.

    2001-01-01

    In the framework of new projects of intense spallation neutron sources an extensive experimental and theoretical effort is devoted to the precise prediction and optimization of the targets and shielding in terms of reaction cross sections, hadronic interaction lengths and usable neutrons produced in proton induced spallation reactions. Strong constraints on Monte-Carlo high energy transport codes are put by a measurement campaign of the NESSI (neutron scintillator and silicon detector) collaboration. While the predictive power of inter- and intra-nuclear cascade models coupled to evaporation codes and transport systems is excellent as far as neutron production in thick targets is concerned, there are considerable discrepancies not only between experiments and models, but also among the different codes themselves when regarding charged particle production in thin targets. In the current contribution a representative validation will be executed and possible deficiencies within the codes are elaborated. (orig.)

  10. Excitation functions of radionuclides produced by proton induced reactions on gadolinium targets

    International Nuclear Information System (INIS)

    Challana, M.B.; Comsana, M.N.H.; Moawadb, G.S.; Abou-Zeid, M.A.

    2008-01-01

    Cross section study for proton induced reaction on natural Gadolinium targets were performed. Excitation functions for the reactions n atGd(p,x) 152m+g , 154m,154g Tb from threshold up to E p = 18 MeV have been measured employing the stacked foil activation technique, and using high resolution HPGe gamma spectrometry. Utilizing the simultaneous measurement of the excitation function of n atCu(p,x) 62 Zn, n atCu(p,x) 63 Zn, and n atCu(p,x) 65 Zn as monitor reactions. The theoretical analysis of the excitation functions has been done employing both ALICE-91 and EMPIRE-II codes. In general, theoretical calculations agree well with the experimental data. A significant contribution of pre-equilibrium component has been observed at these energies

  11. Experimental studies on excitation functions of the proton-induced activation reactions on silver

    International Nuclear Information System (INIS)

    Uddin, M.S.; Hagiwara, M.; Baba, M.; Tarkanyi, F.; Ditroi, F.

    2005-01-01

    Excitation functions were measured for the production of 106m,105 Ag, 103,101,100 Pd, 105,102,101m,100,99 Rh and 97 Ru via proton-induced activation reactions on natural silver using a stacked foil technique in the energy range 11-80 MeV. The residual activity measurements were carried out nondestructively by the high-resolution HPGe γ-ray spectroscopy. Thick target integral yields were deduced using the measured cross-sections from the respective threshold energies of the investigated reactions up to 80 MeV. The present work gives new results for the investigated radionuclides. The data in MENDL-2P deduced with the theoretical model code ALICE-IPPE are consistent in shape with the measured values, but show disagreement in magnitude

  12. Development of a system of measuring double-differential cross sections for proton-induced reactions

    Energy Technology Data Exchange (ETDEWEB)

    Harada, M.; Watanabe, Y.; Sato, K. [Kyushu Univ., Fukuoka (Japan); Meigo, S.

    1997-03-01

    We report the present status of a counter telescope and a data acquisition system which are being developed for the measurement of double-differential cross sections of all light-charged particles emitted from proton-induced reactions on {sup 12}C at incident energies less than 90 MeV. The counter telescope consists of an active collimator made of a plastic scintillator, two thin silicon {Delta}E-detectors and a CsI(Tl) E-detectors with photo-diode readout. Signals from each detector are processed using the data acquisition system consisting of the front-end electronics (CAMAC) and two computers connected with the ethernet LAN: a personal computer as the data collector and server, and a UNIX workstation as the monitor and analyzer. (author)

  13. The isolation of 139Ce after production by a proton-induced nuclear reaction on praseodymium

    International Nuclear Information System (INIS)

    Van der Walt, T.N.; Vermeulen, C.

    2004-01-01

    A method, based on anion exchange chromatography, is presented for the isolation of 139 Ce after production by a proton-induced nuclear reaction on a thick praseodymium target. After bombardment the target is dissolved in nitric acid and 139 Ce oxidised to the Ce(IV) oxidation state with bromic acid. 139 Ce is then separated form the praseodymium by anion exchange chromatography on a Ag MP-1 resin column in a nitric acid - bromic acid mixture. 139 Ce is sorbed onto the resin column and praseodymium eluted with the acid mixture. The bromic acid is washed out of the column with nitric acid and 139 Ce finally eluted with dilute nitric acid containing sulphur dioxide

  14. Spallation reactions and energy deposition in heavy target materials comparison of measurements and MC-calculations

    International Nuclear Information System (INIS)

    Filges, D.; Enke, M.; Galin, J.

    2001-01-01

    A renascence of interest for energetic proton induced production of neutrons originates recently by the inception of new projects for target stations of intense spallation neutron sources (like the planned European Spallation Source ESS), accelerator-driven nuclear reactors, nuclear waste transmutation and also the application for radioactive beams. Here we verify the predictive power of transport codes currently on the market by confronting observables and quantities of interest with an exhaustive matrix of benchmark data essentially coming from two experiments being performed at the Cooler Synchrotron COSY at Juelich. Program packages like HERMES, LCS or MCNPX master the prevision of reaction cross sections, hadronic interaction lengths, averaged neutron multiplicities and neutron multiplicity distributions in thick and thin(!) targets for a wide spectrum of incident proton energies, geometrical shapes and materials of the target. While also the observables related to the energy deposition in thick targets are in a good agreement with the model predictions, the production cross section measurements however for light charged particles on thin targets point out that problems exist within these models. (author)

  15. Experimental determination of proton induced reaction cross sections on {sup nat}Ni near threshold energy

    Energy Technology Data Exchange (ETDEWEB)

    Uddin, Md. Shuza [Atomic Energy Research Establishment, Dhaka (Bangladesh). Tandem Accelerator Facilities; Forschungszentrum Juelich GmbH (Germany). Inst. fuer Neurowissenschaften und Medizin, INM-5: Nuklearchemie; Chakraborty, Animesh Kumer [Atomic Energy Research Establishment, Dhaka (Bangladesh). Tandem Accelerator Facilities; Chittagong University of Engineering and Technology (Bangladesh). Dept. of Physics; Spellerberg, Stefan; Spahn, Ingo; Qaim, Syed M. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Neurowissenschaften und Medizin, INM-5: Nuklearchemie; Shariff, Md. Asad; Das, Sopan [Atomic Energy Research Establishment, Dhaka (Bangladesh). Tandem Accelerator Facilities; Rashid, Md. Abdur [Chittagong University of Engineering and Technology (Bangladesh). Dept. of Physics

    2016-08-01

    A newly developed facility at the 3 MV Tandem Accelerator at Dhaka for measurement of proton induced reaction cross sections in the energy region below 5 MeV is outlined and tests for the beam characterization are described. The results were validated by comparison with the well-known excitation function of the {sup 64}Ni(p, n){sup 64}Cu reaction. Excitation functions of the reactions {sup nat}Ni(p, x){sup 60,61}Cu, {sup nat}Ni(p, x){sup 55,57,58m+g}Co and {sup nat}Ni(p, x){sup 57}Ni were also measured from threshold to 16 MeV using the stacked-foil technique, whereby irradiations were performed with 5 MeV protons available at the Tandem Accelerator and 16.7 MeV protons at the BC 1710 cyclotron at Juelich, Germany. The radioactivity was measured using HPGe γ-ray detectors. A few results are new, the others strengthen the database. In particular, the results of the reaction {sup nat}Ni(p, x){sup 61}Cu below 3 MeV could serve as beam monitor.

  16. Percolation-fission model study of the fragment mass distribution for the 1 GeV proton induced reaction

    International Nuclear Information System (INIS)

    Katsuma, Masahiko; Kobayashi, Hiroshi; Sawada, Tetsuo; Sasa, Toshinobu

    2005-01-01

    The 1 GeV proton induced reaction on 208 Pb targets is analyzed by using the percolation model combined with the Atchison fission model. The fragment mass distribution and the isotopic production cross sections obtained from our model are compared with the experimental data. The trends of the fragment mass distribution for the 1 GeV proton induced reaction can be reproduced by our calculation in some degree. The order of magnitude for the calculated isotopic production cross sections at the calculated peak positions is similar to that of the experimental peak values. The calculated peak positions of the isotopic production cross sections are shifted to the heavier region than those of the experimental data. (author)

  17. Production of He-, Ne-, Ar-, Kr-, and Xe-isotopes by proton-induced reactions on lead

    International Nuclear Information System (INIS)

    Leya, I.; Michel, R.

    2003-01-01

    We measured integral thin target cross sections for the proton-induced production of He-, Ne-, Ar-, Kr-, and Xe-isotopes from lead from the respective reaction thresholds up to 2.6 GeV. The production of noble gas isotopes in lead by proton-induced reactions is of special importance for design studies of accelerator driven systems and energy amplifiers. In order to minimise the influences of secondary particles on the production of residual nuclides a new Mini-Stack approach was used instead of the well-known stacked-foil techniques for all experiments with proton energies above 200 MeV. With some exceptions our database for the proton-induced production of noble gas isotopes from lead is consistent and nearly complete. In contradistinction to the production of He from Al and Fe, where the cross sections obtained by thin-target irradiation experiments are up to a factor of 2 higher than the NESSI data, both datasets agree for the He production from lead. (orig.)

  18. Cross sections and thermonuclear reaction rates of proton-induced reactions on 37Cl

    International Nuclear Information System (INIS)

    Weber, R.O.; Tingwell, C.I.W.; Mitchell, L.W.; Sevior, M.E.; Sargood, D.G.

    1984-01-01

    The yields of γ-rays from the reactions of 37 Cl(p,γ) 38 Ar and 37 Cl(p,αγ) 34 S have been measured as a of bombarding energy over the ranges 0.65 - 2.15 MeV and 1.25 -2.15 MeV respectively, and the yield of neutrons from 37 Cl(p,n) 37 Ar from threshold to 2.50 MeV. The results are compared with global statistical-model calculations and thermonuclear reaction rates are calculated for the temperature range 5 x 10 8 - 10 10 K. The significance of these thermonuclear reaction rates for stellar nucleosynthesis calculations is discussed

  19. Light particle production in spallation reactions induced by protons of 0.8-2.5 GeV incident kinetic energy

    International Nuclear Information System (INIS)

    Herbach, Claus-Michael; Enke, Michael; Boehm, Andreas

    2002-01-01

    Absolute production cross sections have been measured simultaneously for neutrons and light charged particles in 0.8-2.5 GeV proton induced spallation reactions for a series of target nuclei from aluminum up to uranium. The high detection efficiency both for neutral and charged evaporative particles provides an event-wise access to the amount of projectile energy dissipated into nuclear excitation. Various intra nuclear cascade plus evaporation models have been confronted with the experimental data showing large discrepancies for hydrogen and helium production. (author)

  20. Investigation of coulomb and pairing effects using new developed empirical formulas for proton-induced reaction cross sections

    International Nuclear Information System (INIS)

    Tel, E.; Aydin, E. G.; Aydin, A.; Kaplan, A.; Boeluekdemir, M. H.; Okuducu, S.

    2010-01-01

    We have investigated Coulomb and pairing effects by using new empirical formulas including the new coefficients for (p, α) at 17.9 MeV, (p, np) at 22.3 MeV, and (p, nα) at 24.8 and 28.5 MeV energies. A new formula is obtained by adjusting Levkovskii's original asymmetry parameter formula and also Tel et al. formula for proton-induced reactions. The new coefficients by using least-squares fitting method for the reactions are determined. In addition, the findings of the present study are compared with the available experimental data.

  1. High-energy nuclear reaction mechanisms - fission, fragmentation and spallation

    International Nuclear Information System (INIS)

    Kaufman, S.B.

    1987-01-01

    Measurements of the correlations in kinetic energy, mass, charge, and angle of coincident fragments formed in high-energy nuclear reactions have helped to characterize the processes of fission, fragmentation and spallation. For example, fission or fission-like two-body breakup mechanisms result in a strong angular correlation between two heavy fragments; in addition, the momentum transfer in the reaction can be deduced from the correlation. Another example is the multiplicity of light charged particles associated with a given heavy fragment, which is a measure of the violence of the collision, thus distinguishing between central and peripheral collisions. A summary of what has been learned about these processes from such studies will be given, along with some suggestions for further experiments

  2. Constraining statistical-model parameters using fusion and spallation reactions

    Directory of Open Access Journals (Sweden)

    Charity Robert J.

    2011-10-01

    Full Text Available The de-excitation of compound nuclei has been successfully described for several decades by means of statistical models. However, such models involve a large number of free parameters and ingredients that are often underconstrained by experimental data. We show how the degeneracy of the model ingredients can be partially lifted by studying different entrance channels for de-excitation, which populate different regions of the parameter space of the compound nucleus. Fusion reactions, in particular, play an important role in this strategy because they fix three out of four of the compound-nucleus parameters (mass, charge and total excitation energy. The present work focuses on fission and intermediate-mass-fragment emission cross sections. We prove how equivalent parameter sets for fusion-fission reactions can be resolved using another entrance channel, namely spallation reactions. Intermediate-mass-fragment emission can be constrained in a similar way. An interpretation of the best-fit IMF barriers in terms of the Wigner energies of the nascent fragments is discussed.

  3. Cross Sections for the Production of Residual Nuclides by Proton-Induced Reactions with Uranium at Medium Energies

    International Nuclear Information System (INIS)

    Issa, S.A.M.; Michel, R.; Uosif, M.A.M.; Issa, S.A.M.; Flamentc, J.L.; David, J.C.; Leray, S.

    2009-01-01

    The production of residual nuclides by proton-induced reactions on uranium is investigated using activated targets from irradiation experiments at Saturne II synchrocyclotron at the Laboratory National Saturne/Saclay. These investigations contribute to the European research project NUDATRA within the IP EUROTRANS in which the feasibility of accelerator-driven transmutation of nuclear waste is evaluated. Experimental cross sections are derived from gamma-spectrometric measurements. A total of 1894 cross-section was deter-mined covering 44 residual nuclides in the energy range from 211 MeV to 2530 MeV. The experimental data together with those of earlier work of our group are discussed in the context of theoretical excitation functions calculated by the newly developed INCL4 + ABLA and the TALYS codes

  4. Heavy ion and proton-induced single event multiple upset

    International Nuclear Information System (INIS)

    Reed, R.A.; Carts, M.A.; Marshall, P.W.

    1997-01-01

    Individual ionizing heavy ion events are shown to cause two or more adjacent memory cells to change logic states in a high density CMOS SRAM. A majority of the upsets produced by normally incident heavy ions are due to single-particle events that causes a single cell to upset. However, for grazing angles a majority of the upsets produced by heavy-ion irradiation are due to single-particle events that cause two or more cells to change logic states. Experimental evidence of a single proton-induced spallation reaction that causes two adjacent memory cells to change logic states is presented. Results from a dual volume Monte-Carlo simulation code for proton-induced single-event multiple upsets are within a factor of three of experimental data for protons at normal incidence and 70 degrees

  5. Dissertation: Precompound Emission of Energetic Light Fragments in Spallation Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Kerby, Leslie Marie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-08-04

    Emission of light fragments (LF) from nuclear reactions is an open question. Different reaction mechanisms contribute to their production; the relative roles of each, and how they change with incident energy, mass number of the target, and the type and emission energy of the fragments is not completely understood. None of the available models are able to accurately predict emission of LF from arbitrary reactions. However, the ability to describe production of LF (especially at energies ≳ 30 MeV) from many reactions is important for different applications, such as cosmic-ray-induced Single Event Upsets (SEUs), radiation protection, and cancer therapy with proton and heavy-ion beams, to name just a few. The Cascade-Exciton Model (CEM) version 03.03 and the Los Alamos version of the Quark-Gluon String Model (LAQGSM) version 03.03 event generators in Monte Carlo N-Particle Transport Code version 6 (MCNP6) describe quite well the spectra of fragments with sizes up to ⁴He across a broad range of target masses and incident energies (up to ~ 5 GeV for CEM and up to ~ 1 TeV/A for LAQGSM). However, they do not predict the high energy tails of LF spectra heavier than ⁴He well. Most LF with energies above several tens of MeV are emitted during the precompound stage of a reaction. The current versions of the CEM and LAQGSM event generators do not account for precompound emission of LF larger than ⁴He. The aim of our work is to extend the precompound model in them to include such processes, leading to an increase of predictive power of LF-production in MCNP6. This entails upgrading the Modified Exciton Model currently used at the preequilibrium stage in CEM and LAQGSM. It also includes expansion and examination of the coalescence and Fermi break-up models used in the precompound stages of spallation reactions within CEM and LAQGSM. Extending our models to include emission of fragments heavier than ⁴He at the precompound stage has indeed provided results that have much

  6. Proton-induced knockout reactions with netron-rich oxygen isotopes at R{sup 3}B

    Energy Technology Data Exchange (ETDEWEB)

    Atar, Leyla [IKP, TU Darmstadt (Germany); GSI (Germany); Collaboration: R3B-Collaboration

    2014-07-01

    Proton-induced knockout reactions are one of the main goal of the experimental program at the future R{sup 3}B (Reactions with Relativistic Radioactive Beams) Experiment at FAIR. It allows us to obtain spectroscopic information about valence and deeply bound single-nucleon states and to study their evolution over a large variation in isospin. Recent studies have shown that the occupancies of loosely bound valence nucleons in neutron- or proton-rich nuclei have a spectroscopic factor close to unity, whereas single-particle strength for deeply bound nucleons is suppressed in isospin asymmetric systems compared to the predictions of the many-body shell model. Further experimental and theoretical studies are needed for a qualitative and quantitative understanding. For this aim a series of measurements have been performed on the complete oxygen isotopic chain using the existing experimental setup LAND/R{sup 3}B at GSI. We present the main scientific goals, the concepts of the experiment and the preliminary results.

  7. New excitation functions for proton induced reactions on natural titanium, nickel and copper up to 70 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Garrido, E. [SUBATECH, Ecole des Mines de Nantes, Université de Nantes, CNRS/IN2P3, Nantes (France); Duchemin, C., E-mail: Charlotte.Duchemin@subatech.in2p3.fr [SUBATECH, Ecole des Mines de Nantes, Université de Nantes, CNRS/IN2P3, Nantes (France); Guertin, A. [SUBATECH, Ecole des Mines de Nantes, Université de Nantes, CNRS/IN2P3, Nantes (France); Haddad, F.; Michel, N. [SUBATECH, Ecole des Mines de Nantes, Université de Nantes, CNRS/IN2P3, Nantes (France); GIP Arronax, 1 rue Aronnax, 44817 Saint-Herblain (France); Métivier, V. [SUBATECH, Ecole des Mines de Nantes, Université de Nantes, CNRS/IN2P3, Nantes (France)

    2016-09-15

    Highlights: • Natural titanium, nickel and copper targets. • 70 MeV ARRONAX cyclotron proton beam. • Stacked-foil technique and monitor reactions. • Experimental cross section values. • TALYS code version 1.6. - Abstract: New excitation functions for proton induced nuclear reactions on natural titanium, nickel and copper were measured, using the stacked-foil technique and gamma spectrometry, up to 70 MeV. The experimental cross sections were measured using the Ti-nat(p,x) V-48, Ni-nat(p,x) Ni-57 and Cu-nat(p,x) Zn-62,Co-56 monitor reactions recommended by the International Atomic Energy Agency (IAEA), depending on the investigated energy range. Data have been extracted for the Ti-nat(p,x) Sc-43,44m,46,47,48, V-48, K-42,43, Ni-nat(p,x) Ni-56,57, Co-55,56,57,58, Mn-52,54, Cu-nat(p,x) Cu-61,64, Ni-57, Co-56,57,58,60, Zn-62,65, Mn-54 reactions. Our results are discussed and compared to the existing ones as well as with the TALYS code version 1.6 calculations using default models. Our experimental data are in overall good agreement with the literature. TALYS is able to reproduce, in most cases, the experimental trend. Our new experimental results allow to expand our knowledge on these excitation functions, to confirm the existing trends and to give additional values on a large energy range. This work is in line with the new Coordinated Research Project (CRP) launched by the IAEA to expand the database of monitor reactions.

  8. Theoretical modeling of yields for proton-induced reactions on natural and enriched molybdenum targets.

    Science.gov (United States)

    Celler, A; Hou, X; Bénard, F; Ruth, T

    2011-09-07

    Recent acute shortage of medical radioisotopes prompted investigations into alternative methods of production and the use of a cyclotron and ¹⁰⁰Mo(p,2n)(99m)Tc reaction has been considered. In this context, the production yields of (99m)Tc and various other radioactive and stable isotopes which will be created in the process have to be investigated, as these may affect the diagnostic outcome and radiation dosimetry in human studies. Reaction conditions (beam and target characteristics, and irradiation and cooling times) need to be optimized in order to maximize the amount of (99m)Tc and minimize impurities. Although ultimately careful experimental verification of these conditions must be performed, theoretical calculations can provide the initial guidance allowing for extensive investigations at little cost. We report the results of theoretically determined reaction yields for (99m)Tc and other radioactive isotopes created when natural and enriched molybdenum targets are irradiated by protons. The cross-section calculations were performed using a computer program EMPIRE for the proton energy range 6-30 MeV. A computer graphical user interface for automatic calculation of production yields taking into account various reaction channels leading to the same final product has been created. The proposed approach allows us to theoretically estimate the amount of (99m)Tc and its ratio relative to (99g)Tc and other radioisotopes which must be considered reaction contaminants, potentially contributing to additional patient dose in diagnostic studies.

  9. Theoretical study of cross sections of proton-induced reactions on cobalt

    Directory of Open Access Journals (Sweden)

    Mustafa Yiğit

    2018-04-01

    Full Text Available Nuclear fusion may be among the strongest sustainable ways to replace fossil fuels because it does not contribute to acid rain or global warming. In this context, activated cobalt materials in corrosion products for fusion energy are significant in determination of dose levels during maintenance after a coolant leak in a nuclear fusion reactor. Therefore, cross-section studies on cobalt material are very important for fusion reactor design. In this article, the excitation functions of some nuclear reaction channels induced by proton particles on 59Co structural material were predicted using different models. The nuclear level densities were calculated using different choices of available level density models in ALICE/ASH code. Finally, the newly calculated cross sections for the investigated nuclear reactions are compared with the experimental values and TENDL data based on TALYS nuclear code. Keywords: Cobalt, Nuclear Structural Materials, Reaction Cross Section, TENDL Database

  10. Nuclear bremsstrahlung in proton induced reactions at 190 MeV (first experiments at AGOR)

    NARCIS (Netherlands)

    Wilschut, HW

    1998-01-01

    An overview is given of the first experiments with the new KVI cyclotron AGOR. First experiments have focused on nuclear bremsstrahlung in few-and many-body reactions. A classical introduction to nuclear bremsstrahlung is given. First results on coherent bremsstrahlung are discussed.

  11. Fragment production in 12-GeV proton-induced reactions

    International Nuclear Information System (INIS)

    Hirata, Yuichi; Ohnishi, Akira; Ohtsuka, Naohiko; Nara, Yasushi; Niida, Koji; Chiba, Satoshi; Takada, Hiroshi

    2000-01-01

    We study mass and angular distribution of Intermediate Mass Fragment (IMF) produced from p(12 GeV)+ 197 Au reaction by using JAM cascade model combined with percolation model. Although the mass distribution of IMF is well reproduced, the experimentally observed sideward peak of IMF angular distribution is not explained within present JAM + percolation model. (author)

  12. Theoretical modeling of yields for proton-induced reactions on natural and enriched molybdenum targets

    Energy Technology Data Exchange (ETDEWEB)

    Celler, A; Hou, X [University of British Columbia, Vancouver, BC, Canada, (Canada); Benard, F; Ruth, T, E-mail: aceller@physics.ubc.ca, E-mail: xinchi@phas.ubc.ca, E-mail: fbenard@bccrc.ca, E-mail: truth@triumf.ca [BC Cancer Agency, Vancouver, BC (Canada)

    2011-09-07

    Recent acute shortage of medical radioisotopes prompted investigations into alternative methods of production and the use of a cyclotron and {sup 100}Mo(p,2n){sup 99m}Tc reaction has been considered. In this context, the production yields of {sup 99m}Tc and various other radioactive and stable isotopes which will be created in the process have to be investigated, as these may affect the diagnostic outcome and radiation dosimetry in human studies. Reaction conditions (beam and target characteristics, and irradiation and cooling times) need to be optimized in order to maximize the amount of {sup 99m}Tc and minimize impurities. Although ultimately careful experimental verification of these conditions must be performed, theoretical calculations can provide the initial guidance allowing for extensive investigations at little cost. We report the results of theoretically determined reaction yields for {sup 99m}Tc and other radioactive isotopes created when natural and enriched molybdenum targets are irradiated by protons. The cross-section calculations were performed using a computer program EMPIRE for the proton energy range 6-30 MeV. A computer graphical user interface for automatic calculation of production yields taking into account various reaction channels leading to the same final product has been created. The proposed approach allows us to theoretically estimate the amount of {sup 99m}Tc and its ratio relative to {sup 99g}Tc and other radioisotopes which must be considered reaction contaminants, potentially contributing to additional patient dose in diagnostic studies.

  13. Analysis of the proton-induced reactions at 150 MeV - 24 GeV by high energy nuclear reaction code JAM

    International Nuclear Information System (INIS)

    Niita, Koji; Nara, Yasushi; Takada, Hiroshi; Nakashima, Hiroshi; Chiba, Satoshi; Ikeda, Yujiro

    1999-09-01

    We are developing a nucleon-meson transport code NMTC/JAM, which is an upgraded version of NMTC/JAERI. NMTC/JAM implements the high energy nuclear reaction code JAM for the infra-nuclear cascade part. By using JAM, the upper limits of the incident energies in NMTC/JAERI, 3.5 GeV for nucleons and 2.5 GeV for mesons, are increased drastically up to several hundreds GeV. We have modified the original JAM code in order to estimate the residual nucleus and its excitation energy for nucleon or pion induced reactions by assuming a simple model for target nucleus. As a result, we have succeeded in lowering the applicable energies of JAM down to about 150 MeV. In this report, we describe the main components of JAM code, which should be implemented in NMTC/JAM, and compare the results calculated by JAM code with the experimental data and with those by LAHET2.7 code for proton induced reactions from 150 MeV to several 10 GeV. It has been found that the results of JAM can reproduce quite well the experimental double differential cross sections of neutrons and pions emitted from the proton induced reactions from 150 MeV to several 10 GeV. On the other hand, the results of LAHET2.7 show the strange behavior of the angular distribution of nucleons and pions from the reactions above 4 GeV. (author)

  14. New calculations of cyclotron production cross sections of some positron emitting radioisotopes in proton induced reactions

    International Nuclear Information System (INIS)

    Tel, E.; Aydin, E.G.; Kaplan, A.; Aydin, A.

    2009-01-01

    In this study, new calculations on the excitation functions of 13 C(p, n) 13 N, 14 N (p, α) 11 C, 15 N(p, n) 15 O, 16 O(p, α) 13 N, 18 O(p, n) 18 F, 62 Ni(p, n) 62 Cu, 68 Zn(p, n) 68 Ga and 72 Ge(p, n) 72 As reactions have been carried out in the 5-40 MeV incident proton energy range. In these calculations, the pre-equilibrium and equilibrium effects have been investigated. The pre-equilibrium calculations involve hybrid model, geometry dependent hybrid model, the cascade exciton model and full exciton model. Equilibrium effects were calculated according to Weisskopf-Ewing model. The calculated results have been compared with experimental data taken from literature. (author)

  15. Theoretical calculations of the reaction cross-sections for proton-induced reactions on natural copper using ALICE-IPPE code

    International Nuclear Information System (INIS)

    Alharbi, A.A.; Azzam, A.

    2012-01-01

    A theoretical study of the nuclear-reaction cross sections for proton-induced reactions on 63 Cu and 65 Cu was performed in the proton energy range from threshold values up to 50 MeV. The produced nuclei were different isotopes of Zn, Cu, Ni, Co and Mn, some of which have important applications. The reaction cross-section calculations were performed using the ALICE-IPPE code, which depends on the pre-equilibrium compound nucleus model. This code is suitable for the studied energy and isotopic mass ranges. Approximately 14 excitation functions for the different reactions have been constructed from the calculated cross-section values. The excitation function curves for the proton reactions with natural copper targets have been constructed from those for enriched targets using the natural abundance of the copper isotopes. Comparisons between the calculated excitation functions with those previously experimentally measured are given whenever the experimental values were available. Some statistical parameters were introduced to control the quality of the fitting between both the experimental and the theoretical calculated cross-section values. - Highlights: ► We performed reaction cross section calculations using ALICE-IPPE code. ► We constructed 14 excitation functions for nat Cu(p,xn)Zn,Cu,Ni,Co,Mn reactions. ► The available experimental data were fitted to the performed ALICE-IPPE calculations. ► Statistical parameters were introduced to control the quality of the fitting. ► The code failed to fit the experimental data for reactions with large nucleon emissions.

  16. Evaluation of the transmutation of transuranic using neutrons spectrum from the spallation reaction

    Energy Technology Data Exchange (ETDEWEB)

    Gilberti, Mauricio; Pereira, Claubia, E-mail: mgilber@eletronuclear.gov.br [Eletrobras Termonuclear S.A. (ELETRONUCLEAR), Angra dos Reis, RJ (Brazil); Veloso, Maria A. Fortini, E-mail: claubia@nuclear.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizante, MG (Brazil). Dept. de Engenharia Nuclear

    2013-07-01

    The transmutation of transuranic was analyzed by simulating the neutron flux from different spallation sources across arrays of fissile material with isotopic composition PWR reprocessing. A simplified model of Accelerator-Driven Systems (ADS) containing target, moderator graphite, lead-bismuth coolant or sodium coolant, is used. The simulation was made using the particles transport code MCNPX 2.6.0 which allowed to evaluate the rate of transmutation of actinides (Np, Pu, Am, and Cm) at different locations in the system. The objective of the study is to evaluate which the behavior and influences the spectrum of the spallation in the transmutation without the contribution or interference of multiplier, medium subcritical, which would add the contribution of fission neutrons generated, thus interfering in the analysis. The arrangement enable to infer the influence of hardened neutron flux from the spallation reaction in the transmutation, the results show that this is independent of the target material chosen, and the spectrum of spallation has a negligible importance compared to the influence of moderation and scattering generated by the coolant or moderator used. (author)

  17. Evaluation of the transmutation of transuranic using neutrons spectrum from the spallation reaction

    International Nuclear Information System (INIS)

    Gilberti, Mauricio; Pereira, Claubia; Veloso, Maria A. Fortini

    2013-01-01

    The transmutation of transuranic was analyzed by simulating the neutron flux from different spallation sources across arrays of fissile material with isotopic composition PWR reprocessing. A simplified model of Accelerator-Driven Systems (ADS) containing target, moderator graphite, lead-bismuth coolant or sodium coolant, is used. The simulation was made using the particles transport code MCNPX 2.6.0 which allowed to evaluate the rate of transmutation of actinides (Np, Pu, Am, and Cm) at different locations in the system. The objective of the study is to evaluate which the behavior and influences the spectrum of the spallation in the transmutation without the contribution or interference of multiplier, medium subcritical, which would add the contribution of fission neutrons generated, thus interfering in the analysis. The arrangement enable to infer the influence of hardened neutron flux from the spallation reaction in the transmutation, the results show that this is independent of the target material chosen, and the spectrum of spallation has a negligible importance compared to the influence of moderation and scattering generated by the coolant or moderator used. (author)

  18. Study of the spallation residues in the reaction Au (800 MeV/nucleon) + p

    International Nuclear Information System (INIS)

    Mustapha, Brahim

    1999-01-01

    As a neutron source, the spallation reaction is of importance for different fields of research and for a possible hybrid reactor. The study of spallation residues, their cross sections and their energetic properties, is necessary for such applications and for a better understanding of this process. Several studies of spallation products were done using spectroscopic methods. Only radioactive nuclides were detected. Aiming at a more precise measurement, covering the whole range of spallation residues, this study was done using the reverse kinematics method. A liquid hydrogen target was irradiated by an 800 MeV/nucleon gold beam. The produced nuclei were detected in flight before any radioactive decay with about 10% precision. Independent cross section were then obtained. Velocity distributions were completely reconstructed. In their present forms, the theoretical calculations based upon the two-step model, 'intra-nuclear cascade' + 'evaporation', are unable to reproduce the whole set of experimental aspects. An inter-comparison using different INC/EVA combinations permitted to identify the more significant points in these calculations. The important behaviour of this codes were examined. Due to compensation effects between both steps, cascade and evaporation, this study did not lead to a definite conclusion. (author)

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

    International Nuclear Information System (INIS)

    Iga, Kiminori; Ishibashi, Kenji; Shigyo, Nobuhiro

    1996-01-01

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

  20. A model for consecutive spallation and fragmentation reactions in inverse kinematics at relativistic energies

    International Nuclear Information System (INIS)

    Napolitani, P.; Tassan-Got, L.; Bernas, M.; Armbruster, P.

    2003-04-01

    Secondary reactions induced by relativistic beams in inverse kinematics in a thick target are relevant in several fields of experimental physics and technology, like secondary radioactive beams, production of exotic nuclei close to the proton drip line, and cross-section measurements for applications of spallation reactions for energy production and incineration of nuclear wastes. A general mathematical formulation is presented and successively applied as a tool to disentangle the primary reaction yields from the secondary production in the measurement of fission of a 238 U projectile impinging on a proton target at the energy of 1 A GeV. (orig.)

  1. Studies of short-lived products of spallation fission reactions at TRIUMF

    CERN Document Server

    Bischoff, G; D'Auria, J M; Dautet, H; Lee, J K P; Pate, B D; Wiesehahn, W

    1976-01-01

    The gas-jet recoil transport technique has been used to transport products from spallation and fission reactions from a target chamber to a shielded location for nuclear spectroscopic studies. These involve X- beta - gamma coincidence measurements and (shortly) time- of-flight mass spectroscopy. It has been deduced that the proton beam at present intensities has no appreciable effect on the ability of ethylene and other cluster-producing gases to transport radioactivity. Preliminary results will be presented for shortlived fission products from uranium, and for spallation products of iodine and argon. The latter were obtained from the bombardment of gas and aerosol targets mixed with the transporting gas in the target chamber, which appears to be a generally useful technique.

  2. Measurement of the spallation reaction 56Fe+p in inverse kinematics

    International Nuclear Information System (INIS)

    Boehmer, M.

    2006-01-01

    In this work the spallation reaction 56 Fe+p was investigated in inverse kinematics with regard to complete identification of the heavy residues. A ring imaging Cerenkov counter was used for velocity measurements in the experimental setup located at GSI in Darmstadt. A new fast readout electronic was developed and has been operated successfully in the experiment. Momentum reconstruction was carried out with the ALADiN spectrometer and a new software package written for this purpose. Cross sections and velocity distributions for more than 100 mass separated isotopes could be extracted from the dataset and compared with empirical models and other spallation experiments. The experiences gained in this experiment will be used for systematic improvements in the setup of the new spectrometer R3B at FAIR. (orig.)

  3. Excitation functions of proton induced nuclear reactions on {sup nat}Fe up to 16 MeV, with emphasis on radiochemical determination of low cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Uddin, Md. Shuza [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Neurowissenschaften und Medizin (INM), Nuklearchemie (INM-5); Atomic Energy Research Establishment, Dhaka (Bangladesh). Tandem Accelerator Facilities; Chakraborty, Animesh Kumer [Chittagong Univ. of Engineering and Technology (Bangladesh). Dept. of Physics; Atomic Energy Research Establishment, Dhaka (Bangladesh). Tandem Accelerator Facilities; Spellerberg, Stefan; Spahn, Ingo; Qaim, Syed M. [Forschungszentrum Juelich GmbH (Germany). Inst. fuer Neurowissenschaften und Medizin (INM), Nuklearchemie (INM-5); Shariff, Md. Asad [Atomic Energy Research Establishment, Dhaka (Bangladesh). Tandem Accelerator Facilities; Rashid, Md. Abdur [Chittagong Univ. of Engineering and Technology (Bangladesh). Dept. of Physics

    2017-07-01

    Excitation functions for the formation of the radionuclides {sup 56}Co, {sup 57}Co, {sup 58m+g}Co and {sup 54}Mn via proton induced reactions on natural iron target were measured from their respective thresholds up to 16 MeV using the stacked-foil activation technique and HPGe detector γ-ray spectroscopy. In the threshold energy range, the low cross sections for {sup 54}Mn were measured radiochemically. All the measured values were compared with available experimental data and with theoretical calculations reproduced in TENDL-2015 nuclear data library. New data for the formation of {sup 57}Co, {sup 58}Co and {sup 54}Mn were obtained near their reaction thresholds. Other data obtained strengthen the database. Polynomial fittings of the data measured in this work as well as of all data sets (including the present data) were performed. The present data appear to be closer to theoretical calculations than the literature data.

  4. Production of Energetic Light Fragments in Spallation Reactions

    Directory of Open Access Journals (Sweden)

    Mashnik Stepan G.

    2014-03-01

    Full Text Available Different reaction mechanisms contribute to the production of light fragments (LF from nuclear reactions. Available models cannot accurately predict emission of LF from arbitrary reactions. However, the emission of LF is important formany applications, such as cosmic-ray-induced single event upsets, radiation protection, and cancer therapy with proton and heavy-ion beams, to name just a few. The cascade-exciton model (CEM and the Los Alamos version of the quark-gluon string model (LAQGSM, as implemented in the CEM03.03 and LAQGSM03.03 event generators used in the Los Alamos Monte Carlo transport code MCNP6, describe quite well the spectra of fragments with sizes up to 4He across a broad range of target masses and incident energies. However, they do not predict high-energy tails for LF heavier than 4He. The standard versions of CEM and LAQGSM do not account for preequilibrium emission of LF larger than 4He. The aim of our work is to extend the preequilibrium model to include such processes. We do this by including the emission of fragments heavier than 4He at the preequilibrium stage, and using an improved version of the Fermi Break-up model, providing improved agreement with various experimental data.

  5. New findings on the onset of thermal disassembly in spallation reactions

    International Nuclear Information System (INIS)

    Napolitani, P.

    2004-09-01

    Thermal multifragmentation is the process of multi body disassembly of a hot nucleus when the excitation is almost purely thermal i.e. dynamical effects like compression (characteristic of ion-ion collisions at Fermi energy) are negligible. Suited reactions are proton induced collision or ion-ion abrasion at relativistic incident energy. Thus we measured four systems at FRS (Fragment separator, GSI, Darmstadt) in inverse kinematics: Fe 56 +p, Fe 56 +Ti(nat), Xe 136 +p, Xe 136 +Ti(nat) a 1 A*GeV. The inverse kinematics allows to observe all particles without any threshold in energy. This is a great advantage compared to experiments in direct kinematics, because only in inverse kinematics it is possible to obtain complete velocity spectra (without a hole for low velocities) for fully identified isotopes. The complex shape of the velocity spectra allows to identify the different deexcitation channels and it clearly shows the transition from a chaotic-dominated process (Gaussian cloud in velocity space) to a direct Coulomb- (or eventually expansion-) dominated process (shell of a sphere in velocity space). Different possible descriptions of the reaction process are discussed, based either on asymmetric fission or multifragmentation. The resulting physical picture is especially interesting for the Fe 56 +p, and Xe 136 +p systems: proton induced collisions could result in the split of the system in two or more fragments due to a fast break-up process. In this case, the configuration of the break-up partition is very asymmetric. The discussion will be extended to other characteristics, like the restoring of nuclear structure features in the isotopic production and the temperature dependence of the isotopic composition of the residues. (author)

  6. Activation cross-section measurements of some proton induced reactions on Ni, Co and Mo for proton activation analysis (PAA) purposes

    International Nuclear Information System (INIS)

    Alharbi, A.A.; Alzahrani, J.; Azzam, A.; Nuclear Research Center, Cairo

    2011-01-01

    The experimental proton induced reaction cross sections on some elements of the Havar alloy were measured using the activation method and the well established stacked-foil technique combined with high resolution gamma-ray spectroscopy. They included the reactions nat Ni(p,x) 57 Ni, nat Co(p,x) 58(m+g) Co and nat Mo(p,x) 94g,95g,96(m+g) Tc, the aim being to obtain reliable data in the proton energy range up to 26 MeV for some important reactions to be used in the proton activation analysis of steel or other alloys. Irradiations were performed using the CS-30 Cyclotron at KFSH and RC, Riyadh, Saudi Arabia. The activity measurements were carried out in PNU laboratories, Riyadh, Saudi Arabia. The experimental excitation functions for the investigated reactions were constructed and compared with the performed computed theoretical nuclear model calculations using two different codes: ALICE-IPPE and TALYS. A comparison between our measured cross-section values and the available published data is also presented, with a view to checking the consistency of the reported experimental work from various laboratories.

  7. Excitation functions of proton-induced reactions on natural Nd in the 10-30 MeV energy range, and production of radionuclides relevant for double-beta decay

    Czech Academy of Sciences Publication Activity Database

    Lebeda, Ondřej; Lozza, V.; Schrock, P.; Štursa, Jan; Zuber, K.

    2012-01-01

    Roč. 89, č. 4 (2012), 049905/1-049905/12 ISSN 0556-2813 R&D Projects: GA MŠk LA09013 Institutional research plan: CEZ:AV0Z10480505 Keywords : proton-induced reactions * radionuclides Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 3.715, year: 2012

  8. Spallation reactions in shock waves at supernova explosions and related problems

    Energy Technology Data Exchange (ETDEWEB)

    Ustinova, G. K., E-mail: ustinova@dubna.net.ru [RAS, V.I. Vernadsky Institute of Geochemistry and Analytical Chemistry (Russian Federation)

    2013-05-15

    The isotopic anomalies of some extinct radionuclides testify to the outburst of a nearby supernova just before the collapse of the protosolar nebula, and to the fact that the supernova was Sn Ia, i.e. the carbon-detonation supernova. A key role of spallation reactions in the formation of isotopic anomalies in the primordial matter of the Solar System is revealed. It is conditioned by the diffusive acceleration of particles in the explosive shock waves, which leads to the amplification of rigidity of the energy spectrum of particles and its enrichment with heavier ions. The quantitative calculations of such isotopic anomalies of many elements are presented. It is well-grounded that the anomalous Xe-HL in meteoritic nanodiamonds was formed simultaneously with nanodiamonds themselves during the shock wave propagation at the Sn Ia explosion. The possible effects of shock wave fractionation of noble gases in the atmosphere of planets are considered. The origin of light elements Li, Be and B in spallation reactions, predicted by Fowler in the middle of the last century, is argued. All the investigated isotopic anomalies give the evidence for the extremely high magnetohydrodynamics (MHD) conditions at the initial stage of free expansion of the explosive shock wave from Sn Ia, which can be essential in solution of the problem of origin of cosmic rays. The specific iron-enriched matter of Sn Ia and its MHD-separation in turbulent processes must be taking into account in the models of origin of the Solar System.

  9. Design of an experimental device dedicated to the measurement of spallation reactions; Mise au point d'un dispositif experimental pour des mesures exclusives des reactions de spallation

    Energy Technology Data Exchange (ETDEWEB)

    Lafriakh, A

    2005-12-15

    Spallation mechanisms are not yet completely understood, especially because of the difficulty of experimentally disentangling the effects of the different steps of the reaction. In order to understand these mechanisms, we have developed a new experimental device able to perform inclusive measurements. We propose a detection system based on a combination of ionization chambers and proportional counters and on a wall of plastic scintillators to measure light charged particles. In particular the detection of light charged particles is described in detail. In order to validate our device, we have compared our preliminary results obtained on the Fe{sup 56} + p system at 1 GeV/u with inclusive measurements previously obtained at the FRS spectrometer of the GSI facility. A comparison of charge differential cross section shows reasonable agreement. However, our new device allowed extension of those measurements down to Z = 1 and Z = 2. These cross sections are important for material damage studies. Taking into account our error brackets, the evolution of mean longitudinal velocities with respect to residue masses is comparable to that obtained at the FRS. These first results, although preliminary, allow us to validate our experimental device. It is now possible to exploit the strong points of our exclusive measurements, namely correlations between different measured observables. Finally, experimental problems encountered will be taken into account in the future experimental programs, in order to ensure the best measurements conditions.

  10. An update on measurements of helium-production reactions with a spallation neutron source

    International Nuclear Information System (INIS)

    Haight, R.C.; Bateman, F.B.; Chadwick, M.B.

    1995-01-01

    This report gives the status, updated since the last Research Coordination Meeting, of alpha-particle production cross sections, emission spectra and angular distributions which we are measuring at the spallation source of fast neutrons at the Los Alamos Meson Physics Facility (LAMPF). Detectors at angles of 30, 60, 90 and 135 degrees are used to identify alpha particles, measure their energy spectra, and indicate the time-of-flight, and hence the energy, of the neutrons inducing the reaction. The useful neutron energy ranges from less than 1 MeV to approximately 50 MeV for the present experimental setup. Targets under study at present include C, N, 0, 27 Al, Si, 51 V, 56 Fe, 59 CO, 58,60 Ni, 89 Y and 93 Nb. Data for 59 Co have been re-analyzed. The results illustrate the capabilities of the approach, agreement with literature values, and comparisons with nuclear reaction model calculations

  11. Improvement of spallation reaction simulation codes NMTC/JAERI and NUCLEUS

    International Nuclear Information System (INIS)

    Nishida, T.; Takada, H.; Kanno, I.; Nakahara, Y.

    1990-01-01

    To make evaluations of theoretical models for nuclear spallation reaction, simulation codes are modified and a new mass formula is used to improve the accuracy of Monte Carlo calculations. The following conclusions are made from analyses of calculated distributions of nuclear spallation products. A difference is found between the Cameron's old and the Uno and Yamada's new mass formula, which is due to the difference in the method used to fit their shell energy terms to measured data for selected nuclei and in data themselves. For nuclides with an atomic number larger than 70, mass excesses calculated by the Camerons's mass formula are greater than those by the Uno and Yamada's one, whereas the reverse tendency is seen for ones with atomic numbers smaller than 70. Analysis shows that the distributions of produced nuclei have patterns that appear natural from a physical point of view when artificial restrictions are removed in counting the nuclide production events. The new mass formula can reproduce fairly well the experimental product yield distributions, especially in the neutron excess side. It is also found that the old mass formula gives lower estimations for the number of produced nuclei than the new one, especially in the nuclide region far from the beta stable line. (N.K.)

  12. High energy nuclear reactions ('Spallation') and their application in calculation of the Acceleration Driven Systems (ADS)

    International Nuclear Information System (INIS)

    Rossi, Pedro Carlos Russo

    2011-01-01

    This work presents a study of high energy nuclear reactions which are fundamental to dene the source term in accelerator driven systems. These nuclear reactions, also known as spallation, consist in the interaction of high energetic hadrons with nucleons in the atomic nucleus. The phenomenology of these reactions consist in two step. In the rst, the proton interacts through multiple scattering in a process called intra-nuclear cascade. It is followed by a step in which the excited nucleus, coming from the intranuclear cascade, could either, evaporates particles to achieve a moderate energy state or fission. This process is known as competition between evaporation and fission. In this work the main nuclear models, Bertini and Cugnon are reviewed, since these models are fundamental for design purposes of the source term in ADS, due to lack of evaluated nuclear data for these reactions. The implementation and validation of the calculation methods for the design of the source is carried out to implement the methodology of source design using the program MCNPX (Monte Carlo N-Particle eXtended), devoted to calculation of transport of these particles and the validation performed by an international cooperation together with a Coordinated Research Project (CRP) of the International Atomic Energy Agency and available jobs, in order to qualify the calculations on nuclear reactions and the de-excitation channels involved, providing a state of the art of design and methodology for calculating external sources of spallation for source driven systems. The CRISP, is a brazilian code for the phenomenological description of the reactions involved and the models implemented in the code were reviewed and improved to continue the qualification process. Due to failure of the main models in describing the production of light nuclides, the multifragmentation reaction model was studied. Because the discrepancies in the calculations of production of these nuclides are attributes to the

  13. New findings on the onset of thermal disassembly in spallation reactions; Nouvelles approches pour l'etude de la multifragmentation thermique dans la spallation

    Energy Technology Data Exchange (ETDEWEB)

    Napolitani, P

    2004-09-15

    Thermal multifragmentation is the process of multi body disassembly of a hot nucleus when the excitation is almost purely thermal i.e. dynamical effects like compression (characteristic of ion-ion collisions at Fermi energy) are negligible. Suited reactions are proton induced collision or ion-ion abrasion at relativistic incident energy. Thus we measured four systems at FRS (Fragment separator, GSI, Darmstadt) in inverse kinematics: Fe{sup 56}+p, Fe{sup 56}+Ti(nat), Xe{sup 136}+p, Xe{sup 136}+Ti(nat) a 1 A*GeV. The inverse kinematics allows to observe all particles without any threshold in energy. This is a great advantage compared to experiments in direct kinematics, because only in inverse kinematics it is possible to obtain complete velocity spectra (without a hole for low velocities) for fully identified isotopes. The complex shape of the velocity spectra allows to identify the different deexcitation channels and it clearly shows the transition from a chaotic-dominated process (Gaussian cloud in velocity space) to a direct Coulomb- (or eventually expansion-) dominated process (shell of a sphere in velocity space). Different possible descriptions of the reaction process are discussed, based either on asymmetric fission or multifragmentation. The resulting physical picture is especially interesting for the Fe{sup 56}+p, and Xe{sup 136}+p systems: proton induced collisions could result in the split of the system in two or more fragments due to a fast break-up process. In this case, the configuration of the break-up partition is very asymmetric. The discussion will be extended to other characteristics, like the restoring of nuclear structure features in the isotopic production and the temperature dependence of the isotopic composition of the residues. (author)

  14. Neutron-induced transmutation reactions in Np-237, Pu-238, and Pu-239 at the massive natural uranium spallation target

    Czech Academy of Sciences Publication Activity Database

    Závorka, L.; Adam, Jindřich; Baldin, A. A.; Čaloun, Pavel; Chilap, V. V.; Furman, W.; Kadykov, M. G.; Khushvaktov, J.; Pronskikh, V. S.; Solnyshkin, A. A.; Sotnikov, V.; Stegailov, V. I.; Suchopár, Martin; Tsoupko-Sitnikov, V. M.; Tyutyunnikov, S. I.; Voronko, V.; Vrzalová, Jitka

    2015-01-01

    Roč. 349, APR (2015), s. 31-38 ISSN 0168-583X R&D Projects: GA MŠk LG14004 Institutional support: RVO:61389005 Keywords : ADS * spent nuclear fuel * transmutation reaction * spallation neutrons Subject RIV: BG - Nuclear , Atomic and Molecular Physics, Colliders Impact factor: 1.389, year: 2015

  15. Status of helium-production reaction studies with a spallation neutron source

    International Nuclear Information System (INIS)

    Haight, R.C.; Bateman, F.B.; Chadwick, M.B.

    1994-01-01

    Alpha--particle production cross sections and spectra are being measured at the spallation source of fast neutrons at the Los Alamos Meson Physics Facility (LAMPF). Detectors at angles of 30, 60, 90 and 135 degree are used to identify alpha particles, measure their energy spectra, and indicate the time-of-flight, and hence the energy, of the neutrons inducing the reaction. The useful neutron energy ranges from less than 1 MeV to approximately 50 MeV for the present experimental setup. Targets under study at present include C, N, O, 27 Al, Si, 51 V, 56 Fe, 59 Co, 58,60 Ni, 89 Y and 93 Nb. Results for 59 Co illustrate the capabilities of the approach

  16. Modelling of the spallation reaction: analysis and testing of nuclear models

    International Nuclear Information System (INIS)

    Toccoli, C.

    2000-01-01

    The spallation reaction is considered as a 2-step process. First a very quick stage (10 -22 , 10 -29 s) which corresponds to the individual interaction between the incident projectile and nucleons, this interaction is followed by a series of nucleon-nucleon collisions (intranuclear cascade) during which fast particles are emitted, the nucleus is left in a strongly excited level. Secondly a slower stage (10 -18 , 10 -19 s) during which the nucleus is expected to de-excite completely. This de-excitation is performed by evaporation of light particles (n, p, d, t, 3 He, 4 He) or/and fission or/and fragmentation. The HETC code has been designed to simulate spallation reactions, this simulation is based on the 2-steps process and on several models of intranuclear cascades (Bertini model, Cugnon model, Helder Duarte model), the evaporation model relies on the statistical theory of Weiskopf-Ewing. The purpose of this work is to evaluate the ability of the HETC code to predict experimental results. A methodology about the comparison of relevant experimental data with results of calculation is presented and a preliminary estimation of the systematic error of the HETC code is proposed. The main problem of cascade models originates in the difficulty of simulating inelastic nucleon-nucleon collisions, the emission of pions is over-estimated and corresponding differential spectra are badly reproduced. The inaccuracy of cascade models has a great impact to determine the excited level of the nucleus at the end of the first step and indirectly on the distribution of final residual nuclei. The test of the evaporation model has shown that the emission of high energy light particles is under-estimated. (A.C.)

  17. Excitation functions for the formation of some short-lived products in proton-induced reactions on silver

    OpenAIRE

    Uddin, M. S.; Baba, M.; Hagiwara, M.; Latif, S. K. A.; Qaim, S. M.

    2008-01-01

    Excitation functions of the Ag-nat(p, xn)Cd-104,Cd-105 and Ag-nat(p, pxn) Ag-103,Ag-104m.g,Ag- 1049 reactions were measured for the first time over the proton energy range of 32 to about 60 MeV. The data were compared with the results of precompound-hybrid model calculations, whereby only partial agreement was obtained. The contribution of the Ag-103 precursor decay to the total formation of the therapeutic radionuclide Pd-103 in proton activation of silver was estimated: it amounted to about...

  18. Excitation functions for the formation of some short-lived products in proton-induced reactions on silver

    International Nuclear Information System (INIS)

    Uddin, M.S.; Latif, S.K.A.; Baba, M.; Hagiwara, M.; Qaim, S.M.

    2008-01-01

    Excitation functions of the nat Ag(p, xn) 104, 105 Cd and nat Ag(p, pxn) 103, 104m,g, 104g Ag reactions were measured for the first time over the proton energy range of 32 to about 60 MeV. The data were compared with the results of precompound-hybrid model calculations, whereby only partial agreement was obtained. The contribution of the 103 Ag precursor decay to the total formation of the therapeutic radionuclide 103 Pd in proton activation of silver was estimated: it amounted to about 70%. The various possible routes for the production of 103 Pd were also considered: the nat Ag(p, x) 103 Pd and 103 Rh(p, n) 103 Pd processes were found to be most interesting. Despite its somewhat lower yield, the latter process is preferred because it can be applied at a low-energy cyclotron. (orig.)

  19. Study of the excited levels of 11C and 12C by the analysis of protons induced reactions

    International Nuclear Information System (INIS)

    Rihet, Y.

    1984-07-01

    The present work is a study of 11 and 12 C excited states by reactions of non polarised protons on 10 B and 11 B. R-matrix analysis of the 10 B excitation curves in the range E p = 0 to 8 MeV was used to establish parameters of 41 levels in 11 C. Isobaric multiplets of T = 1/2 and T = 3/2 states in A = 11 nuclei are deduced. Analysis of 11 B excitation curves in the E p = 0.5 to 7.4 MeV range led to parameter values of 60 levels in 12 C. T = 1 states in A = 12 isobaric nuclei are discussed [fr

  20. Monte Carlo FLUKA code simulation for study of {sup 68}Ga production by direct proton-induced reaction

    Energy Technology Data Exchange (ETDEWEB)

    Mokhtari Oranj, Leila; Kakavand, Tayeb [Physics Faculty, Zanjan University, P.O. Box 451-313, Zanjan (Iran, Islamic Republic of); Sadeghi, Mahdi, E-mail: msadeghi@nrcam.org [Agricultural, Medical and Industrial Research School, Nuclear Science and Technology Research Institute, P.O. Box 31485-498, Karaj (Iran, Islamic Republic of); Aboudzadeh Rovias, Mohammadreza [Agricultural, Medical and Industrial Research School, Nuclear Science and Technology Research Institute, P.O. Box 31485-498, Karaj (Iran, Islamic Republic of)

    2012-06-11

    {sup 68}Ga is an important radionuclide for positron emission tomography. {sup 68}Ga can be produced by the {sup 68}Zn(p,n){sup 68}Ga reaction in a common biomedical cyclotrons. To facilitate optimization of target design and study activation of materials, Monte Carlo code can be used to simulate the irradiation of the target materials with charged hadrons. In this paper, FLUKA code simulation was employed to prototype a Zn target for the production of {sup 68}Ga by proton irradiation. Furthermore, the experimental data were compared with the estimated values for the thick target yield produced in the irradiation time according to FLUKA code. In conclusion, FLUKA code can be used for estimation of the production yield.

  1. On the nucleon effective mass role to the high energy proton spallation reactions

    Energy Technology Data Exchange (ETDEWEB)

    Santos, B.M., E-mail: biank_ce@if.uff.br [Instituto de Física, Universidade Federal Fluminense, Av. Gal. Milton Tavares de Souza, 24210-346 Niterói, RJ (Brazil); Instituto Militar de Engenharia, Praça General Tibúrcio 80, 22290-270 Rio de Janeiro, RJ (Brazil); Pinheiro, A.R.C. [Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150, 22290-180 Rio de Janeiro, RJ (Brazil); Universidade Federal do Acre, BR 364 km 04, 69920-900 Rio Branco, AC (Brazil); Gonçalves, M. [Comissão Nacional de Energia Nuclear, Rua General Severiano 90, 22290-901 Rio de Janeiro, RJ (Brazil); Duarte, S.B. [Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150, 22290-180 Rio de Janeiro, RJ (Brazil); Cabral, R.G. [Instituto Militar de Engenharia, Praça General Tibúrcio 80, 22290-270 Rio de Janeiro, RJ (Brazil)

    2016-04-15

    We explore the effect of the nucleon effective mass to the dynamic evolution of the rapid phase of proton–nucleus spallation reactions. The analysis of the relaxation time for the non-equilibrium phase is studied by variations in the effective mass parameter. We determine the final excitation energy of the hot residual nucleus at the end of cascade phase and the de-excitation of the nuclear system is carried out considering the competition of particle evaporation and fission processes. It was shown that the excitation energy depends of the hot compound residual nucleus at the end of the rapid phase on the changing effective mass. The multiplicity of particles was also analyzed in cascade and evaporation phase of the reaction. The use of nucleon effective mass during cascade phase can be considered as an effect of the many-body nuclear interactions not included explicitly in a treatment to the nucleon–nucleon interaction inside the nucleus. This procedure represents a more realistic scenario to obtain the neutron multiplicity generated in this reaction, which is a benchmark for the calculation of the neutronic in the ADS reactors.

  2. Study of the spallation residues in the reaction Au (800 MeV/nucleon) + p; Etude des residus de spallation dans la reaction Au (800 MeV par nucleon) + p

    Energy Technology Data Exchange (ETDEWEB)

    Mustapha, Brahim [Inst. de Physique Nucleaire, Paris-11 Univ., 91 - Orsay (France)

    1999-09-09

    As a neutron source, the spallation reaction is of importance for different fields of research and for a possible hybrid reactor. The study of spallation residues, their cross sections and their energetic properties, is necessary for such applications and for a better understanding of this process. Several studies of spallation products were done using spectroscopic methods. Only radioactive nuclides were detected. Aiming at a more precise measurement, covering the whole range of spallation residues, this study was done using the reverse kinematics method. A liquid hydrogen target was irradiated by an 800 MeV/nucleon gold beam. The produced nuclei were detected in flight before any radioactive decay with about 10% precision. Independent cross section were then obtained. Velocity distributions were completely reconstructed. In their present forms, the theoretical calculations based upon the two-step model, 'intra-nuclear cascade' + 'evaporation', are unable to reproduce the whole set of experimental aspects. An inter-comparison using different INC/EVA combinations permitted to identify the more significant points in these calculations. The important behaviour of this codes were examined. Due to compensation effects between both steps, cascade and evaporation, this study did not lead to a definite conclusion. (author)

  3. An update on measurements of helium-production reactions with a spallation neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Haight, R.C.; Bateman, F.B.; Chadwick, M.B. [and others

    1995-10-01

    This report gives the status, updated since the last Research Coordination Meeting, of alpha-particle production cross sections, emission spectra and angular distributions which we are measuring at the spallation source of fast neutrons at the Los Alamos Meson Physics Facility (LAMPF). Detectors at angles of 30, 60, 90 and 135{degrees} are used to identify alpha particles, measure their energy spectra, and indicate the time-of-flight, and hence the energy, of the neutrons inducing the reaction. The useful neutron energy ranges from less than 1 MeV to approximately 50 MeV for the present experimental setup. Targets under study at present include C, N, 0, {sup 27}Al, Si, {sup 51}V, {sup 56}Fe, {sup 59}CO, {sup 58,60}Ni, {sup 89}Y and {sup 93}Nb. Data for {sup 59}Co have been re-analyzed. The results illustrate the capabilities of the approach, agreement with literature values, and comparisons with nuclear reaction model calculations.

  4. Modelling of the spallation reaction: analysis and testing of nuclear models; Simulation de la spallation: analyse et test des modeles nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Toccoli, C

    2000-04-03

    The spallation reaction is considered as a 2-step process. First a very quick stage (10{sup -22}, 10{sup -29} s) which corresponds to the individual interaction between the incident projectile and nucleons, this interaction is followed by a series of nucleon-nucleon collisions (intranuclear cascade) during which fast particles are emitted, the nucleus is left in a strongly excited level. Secondly a slower stage (10{sup -18}, 10{sup -19} s) during which the nucleus is expected to de-excite completely. This de-excitation is performed by evaporation of light particles (n, p, d, t, {sup 3}He, {sup 4}He) or/and fission or/and fragmentation. The HETC code has been designed to simulate spallation reactions, this simulation is based on the 2-steps process and on several models of intranuclear cascades (Bertini model, Cugnon model, Helder Duarte model), the evaporation model relies on the statistical theory of Weiskopf-Ewing. The purpose of this work is to evaluate the ability of the HETC code to predict experimental results. A methodology about the comparison of relevant experimental data with results of calculation is presented and a preliminary estimation of the systematic error of the HETC code is proposed. The main problem of cascade models originates in the difficulty of simulating inelastic nucleon-nucleon collisions, the emission of pions is over-estimated and corresponding differential spectra are badly reproduced. The inaccuracy of cascade models has a great impact to determine the excited level of the nucleus at the end of the first step and indirectly on the distribution of final residual nuclei. The test of the evaporation model has shown that the emission of high energy light particles is under-estimated. (A.C.)

  5. Joint ICTP-IAEA advanced workshop on model codes for spallation reactions

    International Nuclear Information System (INIS)

    Filges, D.; Leray, S.; Yariv, Y.; Mengoni, A.; Stanculescu, A.; Mank, G.

    2008-08-01

    The International Atomic Energy Agency (IAEA) and the Abdus Salam International Centre for Theoretical Physics (ICTP) organised an expert meeting at the ICTP from 4 to 8 February 2008 to discuss model codes for spallation reactions. These nuclear reactions play an important role in a wide domain of applications ranging from neutron sources for condensed matter and material studies, transmutation of nuclear waste and rare isotope production to astrophysics, simulation of detector set-ups in nuclear and particle physics experiments, and radiation protection near accelerators or in space. The simulation tools developed for these domains use nuclear model codes to compute the production yields and characteristics of all the particles and nuclei generated in these reactions. These codes are generally Monte-Carlo implementations of Intra-Nuclear Cascade (INC) or Quantum Molecular Dynamics (QMD) models, followed by de-excitation (principally evaporation/fission) models. Experts have discussed in depth the physics contained within the different models in order to understand their strengths and weaknesses. Such codes need to be validated against experimental data in order to determine their accuracy and reliability with respect to all forms of application. Agreement was reached during the course of the workshop to organise an international benchmark of the different models developed by different groups around the world. The specifications of the benchmark, including the set of selected experimental data to be compared to the models, were also defined during the workshop. The benchmark will be organised under the auspices of the IAEA in 2008, and the first results will be discussed at the next Accelerator Applications Conference (AccApp'09) to be held in Vienna in May 2009. (author)

  6. Spallation reaction study for fission products in nuclear waste: Cross section measurements for {sup 137}Cs and {sup 90}Sr on proton and deuteron

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H., E-mail: wanghe@ribf.riken.jp [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Otsu, H.; Sakurai, H.; Ahn, D.S. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Aikawa, M. [Faculty of Science, Hokkaido University, Sapporo 060-0810 (Japan); Doornenbal, P.; Fukuda, N.; Isobe, T. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Kawakami, S. [Department of Applied Physics, University of Miyazaki, Miyazaki 889-2192 (Japan); Koyama, S. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan); Kubo, T.; Kubono, S.; Lorusso, G. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Maeda, Y. [Department of Applied Physics, University of Miyazaki, Miyazaki 889-2192 (Japan); Makinaga, A. [Graduate School of Medicine, Hokkaido University, North-14, West-5, Kita-ku, Sapporo 060-8648 (Japan); Momiyama, S. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan); Nakano, K. [Department of Advanced Energy Engineering Science, Kyushu University, Kasuga, Fukuoka 816-8580 (Japan); Niikura, M. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan); Shiga, Y. [Department of Physics, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima, Tokyo 171-8501 (Japan); RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Söderström, P.-A. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); and others

    2016-03-10

    We have studied spallation reactions for the fission products {sup 137}Cs and {sup 90}Sr for the purpose of nuclear waste transmutation. The spallation cross sections on the proton and deuteron were obtained in inverse kinematics for the first time using secondary beams of {sup 137}Cs and {sup 90}Sr at 185 MeV/nucleon at the RIKEN Radioactive Isotope Beam Factory. The target dependence has been investigated systematically, and the cross-section differences between the proton and deuteron are found to be larger for lighter spallation products. The experimental data are compared with the PHITS calculation, which includes cascade and evaporation processes. Our results suggest that both proton- and deuteron-induced spallation reactions are promising mechanisms for the transmutation of radioactive fission products.

  7. Spallation: understanding for predicting !?

    International Nuclear Information System (INIS)

    David, J.-C.

    2012-01-01

    This HDR report summarizes about ten years spent around spallation reaction modelling. Spallation reactions are defined as interaction of a light particle, say a nucleon, and a nucleus at an incident energy from 100 MeV up to 2-3 GeV. These reactions are divided in two steps. A first and fast phase, direct reactions also called intranuclear cascade, following by a slower phase, deexcitation of the remnant nucleus. Using the combination of INCL4, the intranuclear cascade model developed by the group, and the deexcitation code Abla from GSI, as a connecting thread, the multi-faceted spallation is presented. Chapter one deals with physics and codes, then different types of benchmarks are addressed, followed by several domains where spallation modelling plays a role, and finally, taking advantage of what has been said previously and of what can be read in the literature, new developments are suggested. (author) [fr

  8. Cross-sections of spallation residues produced in 1A GeV 208Pb on proton reactions

    International Nuclear Information System (INIS)

    Wlazlo, W.; Uniwersytet Jagiellonski, Cracow; Enqvist, T.; Armbruster, P.

    2000-02-01

    Spallation residues produced in 1 GeV per nucleon 208 Pb on proton reactions have been studied using the fragment separator facility at GSI. Isotopic production cross-sections of elements from 61 Pm to 82 Pb have been measured down to 0.1 mb with a high accuracy. The recoil kinetic energies of the produced fragments were also determined. The obtained cross-sections agree with most of the few existing gamma-spectroscopy data. Data are compared with different intranuclear-cascade and evaporation-fission models. Drastic deviations were found for a standard code used in technical applications. (orig.)

  9. Extension of the energy range of the experimental activation cross-sections data of longer-lived products of proton induced nuclear reactions on dysprosium up to 65MeV.

    Science.gov (United States)

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

    2015-04-01

    Activation cross-sections data of longer-lived products of proton induced nuclear reactions on dysprosium were extended up to 65MeV by using stacked foil irradiation and gamma spectrometry experimental methods. Experimental cross-sections data for the formation of the radionuclides (159)Dy, (157)Dy, (155)Dy, (161)Tb, (160)Tb, (156)Tb, (155)Tb, (154m2)Tb, (154m1)Tb, (154g)Tb, (153)Tb, (152)Tb and (151)Tb are reported in the 36-65MeV energy range, and compared with an old dataset from 1964. The experimental data were also compared with the results of cross section calculations of the ALICE and EMPIRE nuclear model codes and of the TALYS nuclear reaction model code as listed in the latest on-line libraries TENDL 2013. Copyright © 2015. Published by Elsevier Ltd.

  10. Spallation reaction study for fission products in nuclear waste: Cross section measurements for 137Cs, 90Sr and 107Pd on proton and deuteron

    Directory of Open Access Journals (Sweden)

    Wang He

    2017-01-01

    Full Text Available Spallation reactions for the long-lived fission products 137Cs, 90Sr and 107Pd have been studied for the purpose of nuclear waste transmutation. The cross sections on the proton- and deuteron-induced spallation were obtained in inverse kinematics at the RIKEN Radioactive Isotope Beam Factory. Both the target and energy dependences of cross sections have been investigated systematically. and the cross-section differences between the proton and deuteron are found to be larger for lighter fragments. The experimental data are compared with the SPACS semi-empirical parameterization and the PHITS calculations including both the intra-nuclear cascade and evaporation processes.

  11. Application of on-line HPLC-ICP-MS for the determination of the nuclide abundances of lanthanides produced via spallation reactions in an irradiated tantalum target of a spallation neutron source

    International Nuclear Information System (INIS)

    Kerl, W.; Becker, J.S.; Dietze, H.J.

    1998-01-01

    An analytical procedure has been developed for the determination of spallation nuclides in an irradiated tantalum target using HPLC coupled on-line to ICP-MS after dissolution and separation of the tantalum matrix. Pieces of tantalum were taken from different locations of the irradiated tantalum target which had been used as the target material in a spallation neutron source. Tantalum was dissolved in a HNO 3 /HF mixture and the tantalum matrix was separated by liquid-liquid extraction so that only the spallation nuclides were left in the sample solutions. The major fraction of the spallation nuclides in the tantalum target are lanthanide metals in the μg g -1 concentration range determined in the present study. Additional reaction products are formed by the irradiation of trace impurities in the original tantalum target. The nuclide abundances of the lanthanide metals measured in the tantalum target differ significantly from the natural isotopic composition so that a lot of isobaric interferences of long-lived radionuclides and stable isotopes in the mass spectrum are to be expected. Therefore, all the lanthanide metals had to be separated chemically prior to their mass spectrometric determination. The separation of all rare earth elements was performed by ion chromatography on-line to ICP-MS. The nuclide abundances of each lanthanide were determined using a sensitive double-focusing sector field inductively coupled plasma mass spectrometer. The nuclide abundances of the lanthanides in the irradiated tantalum target calculated theoretically and the experimental results obtained by on-line HPLC-ICP-MS proved to be in good agreement. (orig.)

  12. Spallation production of neutron deficient radioisotopes in North America

    International Nuclear Information System (INIS)

    Jamriska, D.J.; Peterson, E.J.; Carty, J.

    1997-01-01

    The US Department of Energy produces a number of neutron deficient radioisotopes by high energy proton induced spallation reactions in accelerators at Los Alamos National Laboratory in New Mexico and Brookhaven National Laboratory in New York. Research isotopes are also recovered from targets irradiated at TRIUMF in British Columbia, Canada. The radioisotopes recovered are distributed for use in nuclear medicine, environmental research, physics research, and industry worldwide. In addition to the main product line of Sr-82 from either Mo or Rb targets, Cu-67 from ZnO targets, and Ge-68 and RbBr targets, these irradiation facilities also produce some unique isotopes in quantities not available from any other source such as Al-26, Mg-28, Si-32, Ti-44, Fe-52, Gd-148, and Hg-194. The authors will describe the accelerator irradiation facilities at the Los Alamos and Brookhaven National Laboratories. The high level radiochemical processing facilities at Los Alamos and brief chemical processes will be described

  13. Calculations of the main free path on neutron emission cross-section for spallation reaction of target and fuel nuclei

    International Nuclear Information System (INIS)

    Tel, E.; Kisoglu, H. F.; Topaksu, A. K.; Aydin, A.; Kaplan, A.

    2007-01-01

    There are several new technological application fields of fast neutrons such as accelerator-driven incineration/ transmutation of the long-lived radioactive nuclear wastes (in particular transuranium nuclides) to short-lived or stable isotopes by secondary spallation neutrons produced by high-intensity, intermediate-energy, charged-particle beams, prolonged planetary space missions, shielding for particle accelerators. Especially, accelerator driven subcritical systems (ADS) can be used for fission energy production and /or nuclear waste transmutation as well as in the intermediate-energy accelerator driven neutron sources, ions and neutrons with energies beyond 20 MeV, the upper limit of exiting data files that produced for fusion and fission applications. In these systems, the neutron scattering cross sections and emission differential data are very important for reactor neutronics calculations. The transition rate calculation involves the introduction of the parameter of mean free path determines the mean free path of the nucleon in the nuclear matter. This parameter allows an increase in mean free path, with simulation of effect, which is not considered in the calculations, such as conservation of parity and angular momentum in intra nuclear transitions. In this study, we have investigated the multiple preequilibrium matrix element constant from internal transition for Uranium, Thorium, (n,xn) neutron emission spectra. The neutron-emission spectra produced by (n,xn) reactions on nuclei of some target (for spallation) have been calculated. In the calculations, we have used the geometry dependent hybrid model and the cascade exciton model including the effects of the preequilibrium. The pre-equilibrium direct effects have been examined by using full exciton model. All calculated results have been compared with the experimental data. The obtained results have been discussed and compared with the available experimental data and found agreement with each other

  14. Analysis of the spallation residues and the associated particles in the reaction Fe+p at 1 GeV per nucleon

    International Nuclear Information System (INIS)

    Le Gentil, E.

    2006-09-01

    SPALADIN is a new type of spallation experiment that has been carried out at the GSI accelerator facility (Germany) in order to improve the modelling of the spallation reaction. This experiment is based on the coincidence measurement in inverse kinematics of the spallation residues and the de-excitation fragments. This work presents the analysis of Fe 56 + p reaction at 1 GeV per nucleon. Results on cross-sections and heavy residue velocity spectra are compared to previous data and enabled us to characterize the setup. Most of the element production cross-sections have been obtained with an uncertainty below 10 per cent. In the particular case of helium, its production cross-section has been measured to be σ(1 GeV) = (598 ± 67) mb. The knowledge of this cross-section is important to assess the irradiation damage undergone by the window separating the accelerator from the target. The study of the de-excitation of the pre-fragment shows that the evaporation of light particles (Z ≤ 2) is the main way of de-excitation whatever the collision centrality. However, the de-excitation through the emission of intermediate mass fragments is observed in 5% of the events and most of these events correspond to a very asymmetric binary breaking. The velocity distributions of light residues (with regards to the mass of the projectile) show a significant disagreement with the average velocities predicted by spallation codes. (A.C.)

  15. Excitation functions and yields of proton induced reactions at intermediate energies leading to important diagnostics radioisotopes of 52Fe, 77Br, 82Rb, 97Ru, 111In, 123I, 127Xe, 128Cs, 178Ta and 201Tl

    International Nuclear Information System (INIS)

    Rurarz, E.

    1994-01-01

    This report describes investigations of the excitation functions of the proton induced reactions on 14 targets (Mn, Co, Br, Rb, 99 Tc, 113 Cd, 114 Cd, Cd, I, Cs, Ta, 206,207,208 Pb) leading directly or indirectly to the formation of radionuclides 52 Fe, 77 Br, 82 Rb, 97 Ru, 111 In, 123 I, 127 Xe, 128 Cs, 178 Ta and 201 Tl frequently used in diagnostic procedures of nuclear medicine. The measurements of the excitation functions were made over a wide proton energy range from the reaction threshold up to 100 MeV using the stacked foil (or pellet) technique. Small energy steps were used to allow for accurate determination of the structure of excitation functions. For 97 Ru, 111 In and 127 Xe formation with protons, new reaction channels and targets were used and data concerning this method are published for the first time. The data for 52 Fe, 77 Br, 82 Rb, 123 I, 128 Cs and 201 Tl obtained in the present work for the E p =70-100 MeV region are also published for the first time. The measured excitation functions for the formation of desired (and undesired) radionuclides (altogether 28 excitation functions) are compared with the theoretical ones calculated on the basis of a hybrid model of nuclear reactions in the form of the Overlaid Alice computer code. In order to determine the contribution of the competitive reaction channels to the purity of the produced, desired radionuclide, the excitation functions of the accompanying reactions were also calculated. The 122 calculated excitation functions for the possible contaminant are given in the present work. The comparison of experimental excitation functions with the results of model calculations showed satisfactory agreement, especially if one considers, that no parameter adjustment for individual reaction products was undertaken. From the measured excitation functions the production yields for 28 radionuclides mentioned above have been determined (author). 262 refs, 65 figs, 34 tabs

  16. Thermal features of spallation window targets

    International Nuclear Information System (INIS)

    Martinez-Val, J. M.; Sordo, F.; Leon, P. T.

    2007-01-01

    Subcritical nuclear reactors have been proposed for a number of applications, from energy production to fertile-to-fissile conversion, and to transmutation of long-lived radio nuclei into stable or much shorter-lived nuclei. The main advantage of subcritical reactors is their large reactivity margin for not to attain prompt-supercritical power surges. On the contrary, subcritical reactors present some economic drawbacks and technical complexities that deserve suitable attention in the Research and Development phase. Namely, they need a very intense neutron source in order to keep the neutron flux and the reactor power at the required level. The most intense neutron source seems to be based on the proton-induced (or deuteron-induced) spallation reaction in heavy nuclei targets, which present very demanding thermal features that must be properly limited. Those limits pose upper bounds to the neutron yield of the target. In turn, the limits depend on the features of the impinging particle beam and the material composition and geometry of the target. Although the potential design window for spallation targets is rather wide, the analysis presented in this paper identifies specific topics that must properly be covered in the detailed project of a spallation source, in order to avoid unacceptable temperatures and mechanical stresses in the most critical parts of the source. In this paper, some calculations are reported on solid targets (water cooled or helium cooled) and molten metals targets. It is seen that thermal-hydraulic and mechanical calculations of spallation targets are fundamental elements in the coherent design of this type of very intense neutron sources. This coherence implies the need of a suitable trade-off among the relevant beam parameters (proton energy, total intensity and cross-section shape) and the features of the target (structural materials, coolant characteristics and target geometry). The goal of maximizing the neutron yield has to be checked

  17. Excitation functions of proton induced reactions on {sup nat}Fe in the energy region up to 45 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kwangsoo [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Khandaker, Mayeen Uddin [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Naik, Haladhara [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Radiochemistry Division, Bhabha Atomic Research Center, Trombay, Mumbai 400085 (India); Kim, Guinyun, E-mail: gnkim@knu.ac.kr [Department of Physics, Kyungpook National University, Daegu 702-701 (Korea, Republic of)

    2014-03-01

    The excitation functions of various reaction products such as {sup 55,56,57}Co, {sup 52}Fe, {sup 52,54}Mn, and {sup 51}Cr in the {sup nat}Fe(p, x) reactions were measured by the stacked-foil activation technique in the energy range between their respective reaction threshold and 45 MeV at the MC-50 cyclotron of the Korean Institute of Radiological and Medical Sciences, Korea. The present experimental data were compared with the existing literature data. It was found that excitation function of {sup 56,57}Co and {sup 51}Cr from the {sup nat}Fe(p, x) reaction are in agreement with the literature data. However, the cross-sections for {sup nat}Fe(p, x){sup 52}Fe reactions are lower and those for {sup nat}Fe(p, x){sup 52}Mn and {sup nat}Fe(p, x){sup 54}Mn reactions are higher than the literature data. The reaction cross-sections of the above mentioned reaction products were also compared with those from the TENDL-2012 library based on the TALYS-1.4 program as a function of proton energy, which was reproduced the trend of the excitation functions of the experimental {sup nat}Fe(p, x) reaction cross-section. The integral yields for thick target of the investigated radionuclides were calculated from the excitation function.

  18. Evaluation of proton induced reactions on sup 1 sup 0 sup 0 Mo. New cross sections for production of sup 9 sup 9 sup m Tc and sup 9 sup 9 Mo

    CERN Document Server

    Takács, S; Tarkanyi, F; Hermanne, A; Sonck, M

    2003-01-01

    The use of the sup 9 sup 9 Mo -> sup 9 sup 9 sup m Tc generator in nuclear medicine is well established world wide. The production of the sup 9 sup 9 Mo (T sub 1 sub / sub 2 = 66 h) parent as a fission product of sup 2 sup 3 sup 5 U is largely based on the use of reactor technology. From the early 1990's accelerator based production methods to provide either direct produced sup 9 sup 9 sup m Tc or the parent sup 9 sup 9 Mo, were studied and suggested as potential alternatives to the reactor based production of sup 9 sup 9 Mo. A possible pathway for the charged particle production of sup 9 sup 9 sup m Tc and sup 9 sup 9 Mo is irradiation of molybdenum metal with protons via the reaction sup 1 sup 0 sup 0 Mo(p,2n) sup 9 sup 9 sup m Tc and sup 1 sup 0 sup 0 Mo(p,pn) sup 9 sup 9 Mo, respectively. The earlier published excitation functions show large differences in their maximum that result in large differences in the calculated yields. Study the excitation function for these proton-induced reactions was decided. ...

  19. Design of an experimental device dedicated to the measurement of spallation reactions; Mise au point d'un dispositif experimental pour des mesures exclusives des reactions de spallation

    Energy Technology Data Exchange (ETDEWEB)

    Lafriakh, A

    2005-12-15

    Spallation mechanisms are not yet completely understood, especially because of the difficulty of experimentally disentangling the effects of the different steps of the reaction. In order to understand these mechanisms, we have developed a new experimental device able to perform inclusive measurements. We propose a detection system based on a combination of ionization chambers and proportional counters and on a wall of plastic scintillators to measure light charged particles. In particular the detection of light charged particles is described in detail. In order to validate our device, we have compared our preliminary results obtained on the Fe{sup 56} + p system at 1 GeV/u with inclusive measurements previously obtained at the FRS spectrometer of the GSI facility. A comparison of charge differential cross section shows reasonable agreement. However, our new device allowed extension of those measurements down to Z = 1 and Z = 2. These cross sections are important for material damage studies. Taking into account our error brackets, the evolution of mean longitudinal velocities with respect to residue masses is comparable to that obtained at the FRS. These first results, although preliminary, allow us to validate our experimental device. It is now possible to exploit the strong points of our exclusive measurements, namely correlations between different measured observables. Finally, experimental problems encountered will be taken into account in the future experimental programs, in order to ensure the best measurements conditions.

  20. Isotopic production cross-sections and recoil velocities of spallation-fission fragments in the reaction 238U(1A GeV)+e

    CERN Document Server

    Pereira, J; Wlazlo, W; Benlliure, J; Casarejos, E; Armbruster, P; Bernas, M; Enqvist, T; Legrain, R; Leray, S; Rejmund, F; Mustapha, B; Schmidt, K.-H; Stéphan, C; Taïeb, J; Tassan-Got, L; Volant, C; Boudard, A; Czajkowski, S; 10.1103/PhysRevC.75.014602

    2007-01-01

    Fission fragments of 1A GeV 238U nuclei interacting with a deuterium target have been investigatedwith the Fragment Separator (FRS) at GSI (Darmstadt) by measuring their isotopicproduction cross-sections and recoil velocities. The results, along with those obtained recently forspallation-evaporation fragments, provide a comprehensive analysis of the spallation nuclear productionsin the reaction 238U(1A GeV)+d. Details about experiment performance, data reductionand results will be presented.

  1. Hadron correlations in nuclear reactions with production of cumulative protons induced by π- mesons with momentum of 6.0 GeV/c

    International Nuclear Information System (INIS)

    Bayukov, Yu.D.; Vlasov, A.V.; Gavrilov, V.B.

    1981-01-01

    Hardonic correlations were investigated in reactions with the proton backward production induced by 6.0-GeV/c π - mesons on nuclei Be, C, Al, Cu, Cd, Pb, U. The studied correlations indicate an essential role of multiple interactions of the incident particle in production of cumulative protons [ru

  2. Optimization of $^{178m2}$/Hf isomer production in spallation reactions at projectile energies up to 100 MeV using STAPRE and ALICE code simulations

    CERN Document Server

    Kirischuk, V I; Khomenkov, V P; Strilchuk, N V; Zheltonozhskij, V A

    2004-01-01

    /sup 178m2/Hf isomer production in different spallation reactions with protons, alpha particles and neutrons at projectile energies up to 100 MeV has been analyzed using both STAPRE and ALICE code simulations. The STAPRE code was used to calculate the isomeric ratios, while the ALICE code was used to simulate the excitation functions of the respective ground states. A number of spallation reactions have been compared taking into account not only /sup 178m2 /Hf isomer productivity but also, first, the isomeric ratios calculated by the STAPRE code; second, the accumulation of the most undesirable Hf isotopes and isomers, such as /sup 172/Hf, /sup 175 /Hf, and /sup 179m/Hf; and, third, the production of other admixtures and by-products that could degrade the quality of the produced /sup 178m2/Hf isomer sources, including all stable Hf isotopes as well. Possibilities and ways of optimizing /sup 178m2/Hf isomer production in spallation reactions at projectile energies up to 100 MeV are discussed. This can be consi...

  3. Range calculations for spallation recoils in ThF4 by use of the computer code 'Marlowe'

    International Nuclear Information System (INIS)

    Westmeier, W.; Roessler, K.

    1978-12-01

    The determination of cross sections of spallation reactions requires a knowledge of the target thickness since only the products recoiling from the target are measured and their yield depends on the range. The effective target thickness is a function of the projectile's Z, A and spallation recoil energy and, thus, varies for the individual products. The computer code MARLOWE was used to evaluate energy vs. range curves in the binary collisions approximation. The program was extended to the high energy regime taking into account the stripping of electrons from the projectile and the concomitant changes in the interaction potentials especially for the inelastic part of the collisions. A complementary computer program LATTIC was developed for the parameterization of the lattice description. This code enables the application of MARLOWE to target materials with complicated crystallographic structure. Test calculations for a series of projectile/target combinations showed a reasonable agreement with experimental recoil ranges of Pd, Ag, Os and Ir isotopes from proton induced spallation in Ag, In and Pb targets, respectively. MARLOWE was then applied to calculate product ranges of the 232 Th(p,spall)X-reaction in the ployatomic system ThF 4 . The calculated energy vs. range curves enabled the evaluation of the mean spallation recoil ranges for all possible products, e.g. 170.8 μg/cm 2 for 192 Tl, 115.2 μg/cm 2 for 208 At and 37.1 μg/cm 2 for 223 Ac. (orig.)

  4. Calculations of neutron and proton induced reaction cross sections for actinides in the energy region from 10 MeV to 1 GeV

    International Nuclear Information System (INIS)

    Konshin, V.A.

    1995-01-01

    Several nuclear model codes were applied to calculations of nuclear data in the energy region from 10 MeV to 1 GeV. At energies up to 100 MeV the nuclear theory code GNASH was used for nuclear data calculation for incident neutrons for 238 U, 233-236 U, 238-242 Pu, 237 Np, 232 Th, 241-243 Am and 242-247 Cm. At energies from 100 MeV to 1 GeV the intranuclear cascade exciton model including the fission process was applied to calculations of protons and neutrons with 233 U, 235 U, 238 U, 232 Th, 232 Pa, 237 Np, 238 Np, 239 Pu, 241 Am, 242 Am and 242-248 Cm. Determination of parameter systematics was a major effort in the present work that was aimed at improving the predictive capability of the models used. An emphasis was made on a simultaneous analysis of data for a variety of reaction channels for the nucleus considered, as well as of data that are available for nearby nuclei or other incident particles. Comparison with experimental data available on multiple reaction cross sections, isotope yields, fission cross sections, particle multiplicities, secondary particle spectra, and double differential cross sections indicates that the calculations reproduce the trends, and often the details, of the experimental data. (author)

  5. Excitation functions of proton-induced reactions on {sup nat}Fe and enriched {sup 57}Fe with particular reference to the production of {sup 57}Co

    Energy Technology Data Exchange (ETDEWEB)

    Al-Abyad, M. [Institut fuer Nuklearchemie, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany); Cyclotron Facility, Nuclear Research Centre, Atomic Energy Authority, Cairo 13759 (Egypt); Comsan, M.N.H. [Cyclotron Facility, Nuclear Research Centre, Atomic Energy Authority, Cairo 13759 (Egypt); Qaim, S.M. [Institut fuer Nuklearchemie, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany)], E-mail: s.m.qaim@fz-juelich.de

    2009-01-15

    Excitation functions of the reactions {sup nat}Fe(p,xn){sup 55,56,57,58}Co, {sup nat}Fe(p,x){sup 51}Cr, {sup nat}Fe(p,x){sup 54}Mn, {sup 57}Fe(p,n){sup 57}Co and {sup 57}Fe(p,{alpha}){sup 54}Mn were measured from their respective thresholds up to 18.5 MeV, with particular emphasis on data for the production of the radionuclide {sup 57}Co (T{sub 1/2}=271.8 d). The conventional stacked-foil technique was used, and the samples for irradiation were prepared by an electroplating or sedimentation process. The measured excitation curves were compared with the data available in the literature as well as with results of nuclear model calculations. From the experimental data, the theoretical yields of the investigated radionuclides were calculated as a function of the proton energy. Over the energy range E{sub p}=15{yields}5 MeV the calculated yield of {sup 57}Co from the {sup 57}Fe(p,n){sup 57}Co process amounts to 1.2 MBq/{mu}A h and from the {sup nat}Fe(p,xn){sup 57}Co reaction to 0.025 MBq/{mu}A h. The radionuclidic impurity levels are discussed. Use of highly enriched {sup 57}Fe as target material would lead to formation of high-purity {sup 57}Co.

  6. Calculations of neutron and proton induced reaction cross sections for actinides in the energy region from 10MeV to 1GeV

    International Nuclear Information System (INIS)

    Konshin, V.A.

    1995-06-01

    Several nuclear model codes were applied to calculations of nuclear data in the energy region from 10MeV to 1GeV. At energies up to 100MeV the nuclear theory code GNASH was used for nuclear data calculation for neutrons incident for on 238 U, 233-236 U, 238-242 Pu, 237 Np, 232 Th, 241-243 Am and 242-247 Cm. At energies from 100MeV to 1GeV the intranuclear cascade exciton model including the fission process was applied to calculations of protons and neutrons with 233 U, 235 U, 238 U, 232 Th, 232 Pa, 237 Np, 238 Np, 239 Pu, 241 Am, 242 Am and 242-248 Cm. Determination of parameter systematics was a major effort in the present work that was aimed at improving the predictive capability of the models used. An emphasis was placed upon a simultaneous analysis of data for a variety of reaction channels for the nuclei considered, as well as of data that are available for nearby nuclei or for other incident particles. Comparisons with experimental data available on multiple reaction cross sections, isotope yields, fission cross sections, particle multiplicities, secondary particle spectra, and double differential cross sections indicate that the calculations reproduce the trends, and often the details, of the measurements data. (author) 82 refs

  7. Spallation production of neutron deficient radioisotopes in North America

    International Nuclear Information System (INIS)

    Jamriska, D.J.; Peterson, E.J.; Carty, J.

    1997-01-01

    The United States Department of Energy produces a number of neutron deficient radioisotopes by high energy proton induced spallation reactions in accelerators at Los Alamos National Laboratory in New Mexico and Brookhaven National Laboratory in New York. Research isotopes are also recovered from targets irradiated at TRIUMF in British Columbia, Canada. The radioisotopes recovered are distributed for use in nuclear medicine, environmental research, physics research, and industry worldwide. In addition to the main product line of Sr-82 from either Mo or Rb targets, Cu-67 from ZnO targets, and Ge-68 from RbBr targets, these irradiation facilities also produce some unique isotopes in quantities not available from any other source such as Be-10, Al-26, Mg-28, Si-32, El-44, Fe-52, Gd-248, and Hg-194. We will describe the accelerator irradiation facilities at the Los Alamos and Brookhaven National Laboratories. The high level radiochemical processing facilities at Los Alamos and brief chemical processes from Los Alamos and Brookhaven will be described. Chemical separation techniques have been developed to recover the radioisotopes of interest in both high radiochemical purity and yield and at the same time trying to reduce or eliminate the generation of mixed waste. nearly 75 neutron deficient radioisotopes produced in spallation targets have been produced and distributed to researchers around the world since the inception of the program in 1974

  8. Proton induced X-ray emission analysis

    International Nuclear Information System (INIS)

    Khan, Rashiduzzman

    1976-09-01

    The developments in proton induced X-ray emission analysis are reviewed. Techniques for analyzing thick and thin samples of different origin are described. Discussions on the application of proton induced X-ray emission analysis in different fields, comparison of the sensitivity of this method with other analytical techniques, its limitations and possible improvements are presented

  9. Measurement of the spallation reaction {sup 56}Fe+p in inverse kinematics; Messung der Spallationsreaktion {sup 56}Fe+p in inverser Kinematik

    Energy Technology Data Exchange (ETDEWEB)

    Boehmer, M.

    2006-09-25

    In this work the spallation reaction {sup 56}Fe+p was investigated in inverse kinematics with regard to complete identification of the heavy residues. A ring imaging Cerenkov counter was used for velocity measurements in the experimental setup located at GSI in Darmstadt. A new fast readout electronic was developed and has been operated successfully in the experiment. Momentum reconstruction was carried out with the ALADiN spectrometer and a new software package written for this purpose. Cross sections and velocity distributions for more than 100 mass separated isotopes could be extracted from the dataset and compared with empirical models and other spallation experiments. The experiences gained in this experiment will be used for systematic improvements in the setup of the new spectrometer R3B at FAIR. (orig.)

  10. Search for {theta}(1540){sup +} in the exclusive proton-induced reaction p+C(N){yields}{theta}{sup +} anti K{sup 0}+C(N) at the energy of 70 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Antipov, Yu.M.; Artamonov, A.V.; Batarin, V.A.; Eroshin, O.V. [Inst. for High Energy Physics, Protvino (Russian Federation); Kolgamov, V.Z. [Inst. of Theoretical and Experimental Physics, Moscow (RU)] [and others

    2004-09-01

    A search for narrow {theta}(1540){sup +}, a candidate for pentaquark baryon with positive strangeness, has been performed in an exclusive proton-induced reaction p+C(N){yields}{theta}{sup +} anti K{sup 0}+C(N) on carbon nuclei or quasifree nucleons at E{sub beam}=70 GeV ({radical}(s)=11.5 GeV) studying nK{sup +}, pK{sub S}{sup 0} and pK{sub L}{sup 0} decay channels of {theta}(1540){sup +} in four different final states of the {theta}{sup +} anti K{sup 0} system. In order to assess the quality of the identification of the final states with neutron or K {sup 0} {sub L}, we reconstructed {lambda}(1520){yields}nK{sup 0}{sub S} and {phi}{yields}K{sup 0}{sub L}K{sup 0}{sub S} decays in the calibration reactions p+C(N){yields}{lambda}(1520)K{sup +}+C(N) and p+C(N){yields}p{phi}+C(N). We found no evidence for narrow pentaquark peak in any of the studied final states and decay channels. Assuming that the production characteristics of the {theta}{sup +} anti K{sup 0} system are not drastically different from those of the {lambda}(1520)K{sup +} and p{phi} systems, we established upper limits on the cross-section ratios {sigma}({theta}{sup +} anti K{sup 0})/{sigma}({lambda}(1520)K{sup +})< 0.02 and {sigma}({theta}{sup +} anti K{sup 0})/{sigma}(p{phi})< 0.15 at 90% CL and a preliminary upper limit for the forward hemisphere cross-section {sigma}({theta}{sup +} anti K{sup 0})< 30 nb/nucleon. (orig.)

  11. The application of nuclear cross section measurements to spallation reactions in cosmic rays

    International Nuclear Information System (INIS)

    Raisbeck, G.M.; Yiou, F.

    1976-01-01

    The effects and implications of nuclear transformations of the comic ray particles themselves, and how those transformations are simulated in the laboratory are dealt with. Thus, although the majority of cosmic rays are protons and alpha particles, it is the small fraction of heavier species that is the main concern here. These nuclides interact with the interstellar matter (again mostly hydrogen and helium) in which they propagate, and thus can undergo nuclear reactions. For the cosmic ray physicist the effects of these reactions are both favourable and unfavourable. The unfavourable aspect arises from the fact that the composition of the cosmic ray is significantly altered, thus tending to mask an important indication as to their origin. Counterbalancing this is the fact that the effects left by the nuclear reactions are one of the most valuable links with the propagation process itself. A careful unravelling of these effects can thus reveal important information on where and how this propagation takes place. The type of nuclear information needed and techniques that are used to obtain it are considered. (Auth.)

  12. Analysis of the spallation residues and the associated particles in the reaction Fe+p at 1 GeV per nucleon; Analyse des residus de spallation et des particules associees dans la reaction Fe+p a 1 GeV par nucleon

    Energy Technology Data Exchange (ETDEWEB)

    Le Gentil, E

    2006-09-15

    SPALADIN is a new type of spallation experiment that has been carried out at the GSI accelerator facility (Germany) in order to improve the modelling of the spallation reaction. This experiment is based on the coincidence measurement in inverse kinematics of the spallation residues and the de-excitation fragments. This work presents the analysis of Fe{sup 56} + p reaction at 1 GeV per nucleon. Results on cross-sections and heavy residue velocity spectra are compared to previous data and enabled us to characterize the setup. Most of the element production cross-sections have been obtained with an uncertainty below 10 per cent. In the particular case of helium, its production cross-section has been measured to be {sigma}(1 GeV) = (598 {+-} 67) mb. The knowledge of this cross-section is important to assess the irradiation damage undergone by the window separating the accelerator from the target. The study of the de-excitation of the pre-fragment shows that the evaporation of light particles (Z {<=} 2) is the main way of de-excitation whatever the collision centrality. However, the de-excitation through the emission of intermediate mass fragments is observed in 5% of the events and most of these events correspond to a very asymmetric binary breaking. The velocity distributions of light residues (with regards to the mass of the projectile) show a significant disagreement with the average velocities predicted by spallation codes. (A.C.)

  13. Spallation studies at Saturne

    Energy Technology Data Exchange (ETDEWEB)

    Frehaut, J. [Centre d`Etudes de Bruyeres-le-Chatel (France)

    1995-10-01

    SATURNE is a synchrotron accelerator which can deliver particles of momentum P and charge Z up to P/Z = 4 GeV/c. Monokinetic neutron beams of momentum up to 2 GeV/c can be produced. The spallation studies deal with measurements of: (i) differential neutron production cross sections from thin targets, (ii) neutron multiplicity distribution for proton and {sup 3}He induced reactions, and (iii) nuclide production in thin target. Measurements on thick or composite targets are under consideration.

  14. Studying Angular Distribution of Neutron for (p,n) Reaction from 0.5 GeV to 1.5 GeV on some Heavy Targets 238U, 206Pb, 197Au, 186W

    International Nuclear Information System (INIS)

    Nguyen Mong Giao; Tran Thanh Dung; Nguyen Thi Ai Thu; Huynh Thi Xuan Tham

    2010-08-01

    The angular distributions of neutron are calculated for a spallation reaction induced by proton energy from 0.5 GeV to 1.5 GeV on target nuclei 206 Pb, 197 Au, 238 U, 186 W. In this report, we use nuclear data of JENDL-HE with evaluated proton induced cross-sections up to 3 GeV. The obtained results have been discussed in detail. (author)

  15. Spallation neutron production and the current intra-nuclear cascade and transport codes

    International Nuclear Information System (INIS)

    Filges, D.; Goldenbaum, F.

    2001-01-01

    A recent renascent interest in energetic proton-induced production of neutrons originates largely from the inception of projects for target stations of intense spallation neutron sources, like the planned European Spallation Source (ESS), accelerator-driven nuclear reactors, nuclear waste transmutation, and also from the application for radioactive beams. In the framework of such a neutron production, of major importance is the search for ways for the most efficient conversion of the primary beam energy into neutron production. Although the issue has been quite successfully addressed experimentally by varying the incident proton energy for various target materials and by covering a huge collection of different target geometries --providing an exhaustive matrix of benchmark data-- the ultimate challenge is to increase the predictive power of transport codes currently on the market. To scrutinize these codes, calculations of reaction cross-sections, hadronic interaction lengths, average neutron multiplicities, neutron multiplicity and energy distributions, and the development of hadronic showers are confronted with recent experimental data of the NESSI collaboration. Program packages like HERMES, LCS or MCNPX master the prevision of reaction cross-sections, hadronic interaction lengths, averaged neutron multiplicities and neutron multiplicity distributions in thick and thin targets for a wide spectrum of incident proton energies, geometrical shapes and materials of the target generally within less than 10% deviation, while production cross-section measurements for light charged particles on thin targets point out that appreciable distinctions exist within these models. (orig.)

  16. Spallation neutron production and the current intra-nuclear cascade and transport codes

    Science.gov (United States)

    Filges, D.; Goldenbaum, F.; Enke, M.; Galin, J.; Herbach, C.-M.; Hilscher, D.; Jahnke, U.; Letourneau, A.; Lott, B.; Neef, R.-D.; Nünighoff, K.; Paul, N.; Péghaire, A.; Pienkowski, L.; Schaal, H.; Schröder, U.; Sterzenbach, G.; Tietze, A.; Tishchenko, V.; Toke, J.; Wohlmuther, M.

    A recent renascent interest in energetic proton-induced production of neutrons originates largely from the inception of projects for target stations of intense spallation neutron sources, like the planned European Spallation Source (ESS), accelerator-driven nuclear reactors, nuclear waste transmutation, and also from the application for radioactive beams. In the framework of such a neutron production, of major importance is the search for ways for the most efficient conversion of the primary beam energy into neutron production. Although the issue has been quite successfully addressed experimentally by varying the incident proton energy for various target materials and by covering a huge collection of different target geometries --providing an exhaustive matrix of benchmark data-- the ultimate challenge is to increase the predictive power of transport codes currently on the market. To scrutinize these codes, calculations of reaction cross-sections, hadronic interaction lengths, average neutron multiplicities, neutron multiplicity and energy distributions, and the development of hadronic showers are confronted with recent experimental data of the NESSI collaboration. Program packages like HERMES, LCS or MCNPX master the prevision of reaction cross-sections, hadronic interaction lengths, averaged neutron multiplicities and neutron multiplicity distributions in thick and thin targets for a wide spectrum of incident proton energies, geometrical shapes and materials of the target generally within less than 10% deviation, while production cross-section measurements for light charged particles on thin targets point out that appreciable distinctions exist within these models.

  17. Spallation-mechanism and characteristics

    International Nuclear Information System (INIS)

    Strugalski, Z.; Strugalska-Gola, E.; Wojciechowski, A.

    1996-01-01

    Mechanism of spallation is revealed experimentally. Spallation is a complicated nuclear reaction initiated by fast hadron in which three stages may be distinguished: a) the first stage in which the target nucleus is locally damaged, it lasts ∼10 -24 +10 -22 s; b) the slow stage which lasts ∼10 -22 +10 -17 s after the collision started, the damaged and excited nucleus uses to emit the black track leaving particles; c) the final stage in which residual target nucleus uses to split into two or more fragments. Quantitative characteristics of each of the stages are presented. 35 refs

  18. Coprecipitation experiment with Sm hydroxide using a multitracer produced by nuclear spallation reaction: A tool for chemical studies with superheavy elements

    International Nuclear Information System (INIS)

    Kasamatsu, Yoshitaka; Yokokita, Takuya; Toyomura, Keigo; Shigekawa, Yudai; Haba, Hiromitsu; Kanaya, Jumpei; Huang, Minghui; Ezaki, Yutaka; Yoshimura, Takashi; Morita, Kosuke; Shinohara, Atsushi

    2016-01-01

    To establish a new methodology for superheavy element chemistry, the coprecipitation behaviors of 34 elements with samarium hydroxide were investigated using multitracer produced by a spallation of Ta. The chemical reactions were rapidly equilibrated within 10 s for many elements. In addition, these elements exhibited individual coprecipitation behaviors, and the behaviors were qualitatively related to their hydroxide precipitation behaviors. It was demonstrated that the ammine and hydroxide complex formations of superheavy elements could be investigated using the established method. - Highlights: • We established a new methodology for superheavy element (SHE) chemistry. • Coprecipitation behaviors of 34 elements with Sm hydroxide could be simultaneously investigated by using multitracer. • The complex formations were investigated from the coprecipitation behaviors. • The established method will lead to the study on various precipitates of SHEs.

  19. Experimental and Theoretical Investigations to Improve the Predictive Power of Nuclear Reaction Models in Spallation Neutron Production

    International Nuclear Information System (INIS)

    Nuenighoff, K.; Filges, D.; Goldenbaum, F.; Neef, R.D.; Nuenighoff, K.; Paul, N.; Schaal, H.; Sterzenbach, G.; Wohlmuther, M.; Enke, M.; Herbach, C.M.; Hilscher, D.; Jahnke, U.; Tishchenko, V.; Galin, J.; Letourneau, A.; Lott, B.; Peghaire, A.; Pienkowski, L.; Schroeder, U.; Toke, J.; Tietze, A.

    2002-01-01

    In order to design the target station of the European Spallation Source ESS measurements of the neutron production in possible target materials like Pb, Hg and W were performed. The aim of these measurements was to validate the simulation codes and to proof their predictive power. The NESSI experiment allows for the comparison of neutron multiplicity distributions between experiment and simulation, which is a much more sensitive method than only comparing the mean neutron multiplicities. An agreement of better than 10 % was achieved. Various target geometries with diameters up to 15 cm and lengths up to 35 cm over a range from 0.4 till 2.5 GeV incident proton energy were studied. The Monte-Carlo Simulations were performed with the HERMES, LCS, and MCNPX code system. (authors)

  20. An experimental investigation of proton-induced phenomena in krypton

    International Nuclear Information System (INIS)

    Mulders, J.J.L.

    1985-01-01

    In this thesis proton-induced phenomena in krypton gas are described. The considered reactions of protons on krypton are both nuclear and atomic. The nuclear conversion processes mainly result in the production of several Rb radioisotopes, such as 81 Rb that is used in 81 Rb-sup(81m)Kr generator systems for medical diagnostics. The irradiation of krypton gas (natural composition) with protons of about 26 MeV can be used for the routine production of 81 Rb from the direct production reaction 82 Kr(p,2n) 81 Rb and from the indirect reaction 82 Kr(p,2n)sup(81m)Rb → 81 Rb. To determine the scattering of protons in krypton gas targets a quantitative autoradiographic technique was developed. Proton profiles have been determined from the proton-induced activity distribution on a copper foil. For the on-line detection of produced Rb radioisotopes several optical detection techniques were investigated. (Auth.)

  1. Systematics of spallation yields with a four-parameter formula

    International Nuclear Information System (INIS)

    Foshina, M.; Martins, J.B.; Tavares, O.A.P.; Di Napoli, V.

    1982-01-01

    A semi-empirical four-parameter formula is proposed in order to systematize intermediate- and high-energy proton-induced spallation yields of target nuclei covering the 50-100 mass number interval. The measured yields are reproduced by the formula with a degree of accuracy which is comparable with or better than those obtained in previous proton-spallation systematics. The formula predicts reliable values for the most probable mass number of isotopic distributions. For a number of irradiation conditions which may be encountered in practical and physical applications, estimates of proton spallation yields can be obtained by the proposed four-parameter formula with no need of high-speed machines. (M.A.F.) [pt

  2. Physics and technology of spallation neutron sources

    International Nuclear Information System (INIS)

    Bauer, G.S.

    1998-08-01

    Next to fission and fusion, spallation is an efficient process for releasing neutrons from nuclei. Unlike the other two reactions, it is an endothermal process and can, therefore, not be used per se in energy generation. In order to sustain a spallation reaction, an energetic beam of particles, most commonly protons, must be supplied onto a heavy target. Spallation can, however, play an important role as a source of neutrons whose flux can be easily controlled via the driving beam. Up to a few GeV of energy, the neutron production is roughly proportional to the beam power. Although sophisticated Monte Carlo codes exist to compute all aspects of a spallation facility, many features can be understood on the basis of simple physics arguments. Technically a spallation facility is very demanding, not only because a reliable and economic accelerator of high power is needed to drive the reaction, but also, and in particular, because high levels of radiation and heat are generated in the target which are difficult to cope with. Radiation effects in a spallation environment are different from those commonly encountered in a reactor and are probably even more temperature dependent than the latter because of the high gas production rate. A commonly favored solution is the use of molten heavy metal targets. While radiation damage is not a problem in this case, except for the container, a number of other issues are discussed. (author)

  3. Production of complex particles in low energy spallation and in fragmentation reactions by in-medium random clusterization

    International Nuclear Information System (INIS)

    Lacroix, D.; Durand, D.

    2005-09-01

    Rules for in-medium complex particle production in nuclear reactions are proposed. These rules have been implemented in two models to simulate nucleon-nucleus and nucleus-nucleus reactions around the Fermi energy. Our work emphasizes the effect of randomness in cluster formation, the importance of the nucleonic Fermi motion as well as the role of conservation laws. The concepts of total available phase-space and explored phase-space under constraint imposed by the reaction are clarified. The compatibility of experimental observations with a random clusterization is illustrated in a schematic scenario of a proton-nucleus collision. The role of randomness under constraint is also illustrated in the nucleus-nucleus case. (authors)

  4. Spallation neutron sources

    International Nuclear Information System (INIS)

    Fraser, J.S.; Bartholomew, G.A.

    1983-01-01

    The principles and theory of spallation neutron sources are outlined and a comparison is given with other types of neutron source. A summary of the available accelerator types for spallation neutron sources and their advantages and disadvantages is presented. Suitable target materials are discussed for specific applications, and typical target assemblies shown. (U.K.)

  5. Fission-residues produced in the spallation reaction 238U + p at 1 A GeV

    International Nuclear Information System (INIS)

    Bernas, M.; Armbruster, P.; Benlliure, J.; Boudard, A.; Casarejos, E.; Czajkowski, S.; Enqvist, T.; Legrain, R.; Leray, S.; Mustapha, B.; Napolitani, P.; Pereira, J.; Rejmund, F.; Ricciardi, M.V.; Schmidt, K.H.; Stephan, C.; Taieb, J.; Tassan-Got, L.; Volant, C.

    2003-04-01

    Fission fragments from 1 A GeV 238 U projectiles irradiating a hydrogen target were investigated by using the fragment separator FRS for magnetic selection of reaction products including ray-tracing and ΔE-ToF techniques. The momentum spectra of identified fragments were analysed to provide isotopic production cross sections, fission-fragment velocities and recoil momenta of the fissioning parent nuclei. Besides their general relevance, these quantities are also demanded for applications. Calculations and simulations with codes commonly used and recently developed or improved are compared to the data. (orig.)

  6. Study of the production of residual evaporation nuclei issued from the spallation reaction of uranium-238 by 1 GeV protons; Etude de la production de noyaux residuels d'evaporation issus de la reaction de spallation de l'uranium-238 par des protons a 1 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Taieb, J

    2000-10-01

    The spallation reaction by high energy protons is one of the envisaged nuclear reactions for production of exotic nuclei. We have measured the production of more than 300 different evaporation residues issued by the spallation reaction of Uranium-238 by 1 GeV protons. We used the reverse kinematics technique in order to produce the relativistic nuclei and therefore to be able to detect those nuclides within a very short time, shorter in most cases than the radioactive disintegration period. The achieved nuclear charge and mass resolution are excellent. They allow a good accuracy on the values of the measured cross-sections (10 to 15%). We have observed for the first time the nuclide Actinium-235 obtained consequently to the loss of 3 protons by the projectile. The measured isotopic distribution are strongly influenced by the mechanism of fission which leads to a strong reduction of the production of the heavy neutron deficient isotopes. We have compared our results to some other measurements achieved with radio-chemical methods at a similar energy. We observed a systematic disagreement of about 40%. Some comparison with the available systematics show that those are presently not able to reproduce the data with a reasonable precision. We could also measure the recoil momentum distribution for each studied isotopes. We show that Goldhaber's model agrees very well with the experiment in case. of 'cold' channels where the evaporation of particles never occurs. On the other hand, when the produced pre-fragment is excited the data show that Goldhaber's model does not reproduce.the data showing the limitation of such an approach. We finally tried to reproduce the measurement of evaporation residue cross-section thanks to the coupling of intra-nuclear cascade and statistical evaporation codes. The influence of the fission process is rather important is the system p+U; we therefore had to account for the dynamical aspect of the fission. We also showed

  7. Spallator - accelerator breeder

    International Nuclear Information System (INIS)

    Steinberg, M.

    1985-01-01

    The concept involves the use of spallation neutrons produced by interaction of a high energy proton (1 to 2 GeV) from a linear accelerator (LINAC) with a heavy metal target (uranium). The principal spallator concept is based on generating fissile fuel for use in LWR nuclear power plants. The spallator functions in conjunction with a reprocessing plant to regenerate and produce the Pu-239 or U-233 for fabrication into fresh LWR reactor fuel elements. Advances in proton accelerator technology has provided a solid base for predicting performance and optimizing the design of a reliable, continuous wave, high-current LINAC required by a fissile fuel production machine

  8. The study of spallation reactions, neutron production, and transport in a thick lead target and a uranium blanket during 1.5 GeV proton irradiation

    Czech Academy of Sciences Publication Activity Database

    Křížek, Filip; Wagner, Vladimír; Adam, Jindřich; Čaloun, Pavel; Henzl, Vladimír; Henzlová, Daniela; Krása, Antonín; Kugler, Andrej; Majerle, Mitja

    2006-01-01

    Roč. 56, č. 3 (2006), s. 243-252 ISSN 0011-4626 R&D Projects: GA MŠk 1P04LA213 Institutional research plan: CEZ:AV0Z10480505 Keywords : ADS * MCNPX * spallation Subject RIV: BG - Nuclear , Atomic and Molecular Physics, Colliders Impact factor: 0.568, year: 2006

  9. Spallation Neutron Source (SNS)

    Data.gov (United States)

    Federal Laboratory Consortium — The SNS at Oak Ridge National Laboratory is a next-generation spallation neutron source for neutron scattering that is currently the most powerful neutron source in...

  10. Proton induced reactions on Ti, V, Mn, Fe, Co and Ni. Measurement and hybrid model analysis of integral excitation functions and their application in model calculation for the production of cosmogenic nuclides

    International Nuclear Information System (INIS)

    Stueck, R.

    1983-01-01

    By means of the stacked foil technique 67 excitation functions of p induced reactions on the target elements Ti, V, Mn, Fe, Co, and Ni were measured in the energy range between 45 and 200 MeV. For residual nuclei with 42 [de

  11. Quantum molecular dynamics approach to estimate spallation yield ...

    Indian Academy of Sciences (India)

    Consequently, the need for reliable data to design and construct spallation neutron sources has prompted ... A major disadvantage of the QMD code .... have estimated the average neutron multiplicities per primary reaction and kinetic energy.

  12. Results from the IAEA benchmark of spallation models

    International Nuclear Information System (INIS)

    Leray, S.; David, J.C.; Khandaker, M.; Mank, G.; Mengoni, A.; Otsuka, N.; Filges, D.; Gallmeier, F.; Konobeyev, A.; Michel, R.

    2011-01-01

    Spallation reactions play an important role in a wide domain of applications. In the simulation codes used in this field, the nuclear interaction cross-sections and characteristics are computed by spallation models. The International Atomic Energy Agency (IAEA) has recently organised a benchmark of the spallation models used or that could be used in the future into high-energy transport codes. The objectives were, first, to assess the prediction capabilities of the different spallation models for the different mass and energy regions and the different exit channels and, second, to understand the reason for the success or deficiency of the models. Results of the benchmark concerning both the analysis of the prediction capabilities of the models and the first conclusions on the physics of spallation models are presented. (authors)

  13. Excitation functions and yields of proton induced reactions at intermediate energies leading to important diagnostics radioisotopes of {sup 52}Fe, {sup 77}Br, {sup 82}Rb, {sup 97}Ru, {sup 111}In, {sup 123}I, {sup 127}Xe, {sup 128}Cs, {sup 178}Ta and {sup 201}Tl

    Energy Technology Data Exchange (ETDEWEB)

    Rurarz, E. [Soltan Inst. for Nuclear Studies, Otwock-Swierk (Poland)

    1994-12-31

    This report describes investigations of the excitation functions of the proton induced reactions on 14 targets (Mn, Co, Br, Rb, {sup 99}Tc, {sup 113}Cd, {sup 114}Cd, Cd, I, Cs, Ta, {sup 206,207,208}Pb) leading directly or indirectly to the formation of radionuclides {sup 52}Fe, {sup 77}Br, {sup 82}Rb, {sup 97}Ru, {sup 111}In, {sup 123}I, {sup 127}Xe, {sup 128}Cs, {sup 178}Ta and {sup 201}Tl frequently used in diagnostic procedures of nuclear medicine. The measurements of the excitation functions were made over a wide proton energy range from the reaction threshold up to 100 MeV using the stacked foil (or pellet) technique. Small energy steps were used to allow for accurate determination of the structure of excitation functions. For {sup 97}Ru, {sup 111}In and {sup 127}Xe formation with protons, new reaction channels and targets were used and data concerning this method are published for the first time. The data for {sup 52}Fe, {sup 77}Br, {sup 82}Rb, {sup 123}I, {sup 128}Cs and {sup 201}Tl obtained in the present work for the E{sub p}=70-100 MeV region are also published for the first time. The measured excitation functions for the formation of desired (and undesired) radionuclides (altogether 28 excitation functions) are compared with the theoretical ones calculated on the basis of a hybrid model of nuclear reactions in the form of the Overlaid Alice computer code. In order to determine the contribution of the competitive reaction channels to the purity of the produced, desired radionuclide, the excitation functions of the accompanying reactions were also calculated. The 122 calculated excitation functions for the possible contaminant are given. The comparison of experimental excitation functions with the results of model calculations showed satisfactory agreement; no parameter adjustment for individual reaction products was undertaken. Production yields for 28 radionuclides mentioned above were determined (author). 262 refs, 65 figs, 34 tabs.

  14. Experimental studies and nuclear model calculations on proton-induced reactions on $^{nat}$Se, $^{76}$Se and $^{77}$Se with particular reference to the production of the medically interesting radionuclides $^{76}$Br and $^{77}$Br

    CERN Document Server

    Hassan, H E; Coenen, H H; Morsy, M; Qaim, S M; Shubin, Yu; 10.1016/j.apradiso.2004.02.001

    2004-01-01

    Excitation functions of the reactions /sup nat/Se(p, x)/sup 75,76,77,82/Br, /sup 76/Se(p, xn)/sup 75,76/Br, /sup 76/Se(p, x)/sup 75/Se and /sup 77/Se(p, xn)/sup 76,77/Br were measured from their respective thresholds up to 40 MeV, with particular emphasis on data for the production of the medically important radionuclides /sup 76 /Br and /sup 77/Br. The conventional stacked-foil technique was used. The samples were prepared by a sedimentation process. Irradiations were performed using the compact cyclotron CV 28 and the injector of COSY, both at the Research Centre Julich. In order to validate the data, nuclear model calculations were performed using the code ALICE- IPPE which is based on the preequilibrium-evaporation model. Good agreement was found between the experimental and theoretical data, except in the high-energy region where the calculated data were somewhat higher. All the measured excitation curves were compared with the data available in the literature. From the experimental data the theoretical ...

  15. Measurements and Monte Carlo calculations of forward-angle secondary-neutron-production cross-sections for 137 and 200 MeV proton-induced reactions in carbon

    Science.gov (United States)

    Iwamoto, Yosuke; Hagiwara, Masayuki; Matsumoto, Tetsuro; Masuda, Akihiko; Iwase, Hiroshi; Yashima, Hiroshi; Shima, Tatsushi; Tamii, Atsushi; Nakamura, Takashi

    2012-10-01

    Secondary neutron-production double-differential cross-sections (DDXs) have been measured from interactions of 137 MeV and 200 MeV protons in a natural carbon target. The data were measured between 0° and 25° in the laboratory. DDXs were obtained with high energy resolution in the energy region from 3 MeV up to the maximum energy. The experimental data of 137 MeV protons at 10° and 25° were in good agreement with that of 113 MeV protons at 7.5° and 30° at LANSCE/WNR in the energy region below 80 MeV. Benchmark calculations were carried out with the PHITS code using the evaluated nuclear data files of JENDL/HE-2007 and ENDF/B-VII, and the theoretical models of Bertini-GEM and ISOBAR-GEM. For the 137 MeV proton incidence, calculations using JENDL/HE-2007 generally reproduced the shape and the intensity of experimental spectra well including the ground state of the 12N state produced by the 12C(p,n)12N reaction. For the 200 MeV proton incidence, all calculated results underestimated the experimental data by the factor of two except for the calculated result using ISOBAR model. ISOBAR predicts the nucleon emission to the forward angles qualitatively better than the Bertini model. These experimental data will be useful to evaluate the carbon data and as benchmark data for investigating the validity of the Monte Carlo simulation for the shielding design of accelerator facilities.

  16. Spallation Neutron Sources For Science And Technology

    International Nuclear Information System (INIS)

    Comsan, M.N.H.

    2011-01-01

    Spallation Neutron Facilities Increasing interest has been noticed in spallation neutron sources (SNS) during the past 20 years. The system includes high current proton accelerator in the GeV region and spallation heavy metal target in the Hg-Bi region. Among high flux currently operating SNSs are: ISIS in UK (1985), SINQ in Switzerland (1996), JSNS in Japan (2008), and SNS in USA (2010). Under construction is the European spallation source (ESS) in Sweden (to be operational in 2020). The intense neutron beams provided by SNSs have the advantage of being of non-reactor origin, are of continuous (SINQ) or pulsed nature. Combined with state-of-the-art neutron instrumentation, they have a diverse potential for both scientific research and diverse applications. Why Neutrons? Neutrons have wavelengths comparable to interatomic spacings (1-5 A) Neutrons have energies comparable to structural and magnetic excitations (1-100 meV) Neutrons are deeply penetrating (bulk samples can be studied) Neutrons are scattered with a strength that varies from element to element (and isotope to isotope) Neutrons have a magnetic moment (study of magnetic materials) Neutrons interact only weakly with matter (theory is easy) Neutron scattering is therefore an ideal probe of magnetic and atomic structures and excitations Neutron Producing Reactions Several nuclear reactions are capable of producing neutrons. However the use of protons minimises the energetic cost of the neutrons produced solid state physics and astrophysics Inelastic neutron scattering

  17. Radiation effects concerns at a spallation source

    International Nuclear Information System (INIS)

    Sommer, W.F.

    1990-01-01

    Materials used at spallation neutron sources are exposed to energetic particle and photon radiation. Mechanical and physical properties of these materials are altered; radiation damage on the atomic scale leads to radiation effects on the macroscopic scale. Most notable among mechanical-property radiation effects in metals and metal alloys are changes in tensile strength and ductility, changes in rupture strength, dimensional stability and volumetric swelling, and dimensional changes due to stress-induced creep. Physical properties such as electrical resistivity also are altered. The fission-reactor community has accumulated a good deal of data on material radiation effects. However, when the incident particle energy exceeds 50 MeV or so, a new form of radiation damage ensues; spallation reactions lead to more energetic atom recoils and the subsequent temporal and spatial distribution of point defects is much different from that due to a fission-reactor environment. In addition, spallation reactions cause atomic transmutations with these new atoms representing an impurity in the metal. The higher-energy case is of interest at spallation sources; limited detailed data exist for material performance in this environment. 35 refs., 13 figs., 1 tab

  18. Neutron production in spallation reactions of 0.9 and 1.5 GeV protons on a thick lead target. Comparison between experimental data and Monte-Carlo simulations

    International Nuclear Information System (INIS)

    Krasa, A.; Krizek, F.; Wagner, V.; Kugler, A.; Henzl, V.; Henzlova, D.; Majerle, M.; Adam, J.; Caloun, P.; Bradnova, V.; Chultem, D.; Kalinnikov, V.G.; Krivopustov, M.I.; Solnyshkin, A.A.; Stegajlov, V.I.; Tsupko-Sitnikov, V.M.; Tumehndehlgehr, Ts.; Vasil'ev, S.I.

    2005-01-01

    This paper reports on two experiments performed at the Synchrophasotron/Nuclotron accelerator complex at JINR. Relativistic protons with energies 885 MeV and 1.5 GeV hit a massive cylindrical lead target. The spatial and energetic distributions of the neutron field produced by the spallation reactions were measured by the activation of Al, Au, Bi, Co, and Cu foils placed on the surface of the target and close to it. The yields of the radioactive nuclei produced by threshold reactions in these foils were determined by the analyses of their γ spectra. The comparison with Monte-Carlo based simulations was performed both with the LAHET+MCNP code and the MCNPX code

  19. Neutron Production in Spallation Reactions of 0.9 and 1.5 GeV Protons on a Thick Lead Target. Comparison between Experimental Data and Monte-Carlo Simulations

    CERN Document Server

    Krasa, A; Bradnova, V; Caloun, P; Chultem, D; Henzl, V; Henzlová, D; Kalinnikov, V G; Krivopustov, M I; Krízek, F; Kugler, A; Majerle, M; Solnyshkin, A A; Stegailov, V I; Tsoupko-Sitnikov, V M; Tumendelger, T; Vasilev, S I; Wagner, V; Nuclear Physics Institute of Academy of Sciences of Czech Republic, Rez, Czech Republic

    2005-01-01

    This paper reports on two experiments performed at the Synchrophasotron/Nuclotron accelerator complex at JINR. Relativistic protons with energies 885 MeV and 1.5 GeV hit a massive cylindrical lead target. The spatial and energetic distributions of the neutron field produced by the spallation reactions were measured by the activation of Al, Au, Bi, Co, and Cu foils placed on the surface of the target and close to it. The yields of the radioactive nuclei produced by threshold reactions in these foils were determined by the analyses of their $\\gamma$ spectra. The comparison with Monte-Carlo based simulations was performed both with the LAHET+MCNP code and the MCNPX code.

  20. Estimation of thermochemical behavior of spallation products in mercury target

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Kaoru; Kaminaga, Masanori; Haga, Katsuhiro; Kinoshita, Hidetaka; Aso, Tomokazu; Teshigawara, Makoto; Hino, Ryutaro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2002-02-01

    In order to examine the radiation safety of a spallation mercury target system, especially source term evaluation, it is necessary to clarify the chemical forms of spallation products generated by spallation reaction with proton beam. As for the chemical forms of spallation products in mercury that involves large amounts of spallation products, these forms were estimated by using the binary phase diagrams and the thermochemical equilibrium calculation based on the amounts of spallation product. Calculation results showed that the mercury would dissolve Al, As, B, Be, Bi, C, Co, Cr, Fe, Ga, Ge, Ir, Mo, Nb, Os, Re, Ru, Sb, Si, Ta, Tc, V and W in the element state, and Ag, Au, Ba, Br, Ca, Cd, Ce, Cl, Cs, Cu, Dy, Er, Eu, F, Gd, Hf, Ho, I, In, K, La, Li, Lu, Mg, Mn, Na, Nd, Ni, O, Pb, Pd, Pr, Pt, Rb, Rh, S, Sc, Se, Sm, Sn, Sr, Tb, Te, Ti, Tl, Tm, Y, Yb, Zn and Zr in the form of inorganic mercury compounds. As for As, Be, Co, Cr, Fe, Ge, Ir, Mo, Nb, Os, Pt, Re, Ru, Se, Ta, V, W and Zr, precipitation could be occurred when increasing the amounts of spallation products with operation time of the spallation target system. On the other hand, beryllium-7 (Be-7), which is produced by spallation reaction of oxygen in the cooling water of a safety hull, becomes the main factor of the external exposure to maintain the cooling loop. Based on the thermochemical equilibrium calculation to Be-H{sub 2}O binary system, the chemical forms of Be in the cooling water were estimated. Then the Be could exist in the form of cations such as BeOH{sup +}, BeO{sup +} and Be{sup 2+} under the condition of less than 10{sup -8} of the Be mole fraction in the cooling water. (author)

  1. Estimation of thermochemical behavior of spallation products in mercury target

    International Nuclear Information System (INIS)

    Kobayashi, Kaoru; Kaminaga, Masanori; Haga, Katsuhiro; Kinoshita, Hidetaka; Aso, Tomokazu; Teshigawara, Makoto; Hino, Ryutaro

    2002-02-01

    In order to examine the radiation safety of a spallation mercury target system, especially source term evaluation, it is necessary to clarify the chemical forms of spallation products generated by spallation reaction with proton beam. As for the chemical forms of spallation products in mercury that involves large amounts of spallation products, these forms were estimated by using the binary phase diagrams and the thermochemical equilibrium calculation based on the amounts of spallation product. Calculation results showed that the mercury would dissolve Al, As, B, Be, Bi, C, Co, Cr, Fe, Ga, Ge, Ir, Mo, Nb, Os, Re, Ru, Sb, Si, Ta, Tc, V and W in the element state, and Ag, Au, Ba, Br, Ca, Cd, Ce, Cl, Cs, Cu, Dy, Er, Eu, F, Gd, Hf, Ho, I, In, K, La, Li, Lu, Mg, Mn, Na, Nd, Ni, O, Pb, Pd, Pr, Pt, Rb, Rh, S, Sc, Se, Sm, Sn, Sr, Tb, Te, Ti, Tl, Tm, Y, Yb, Zn and Zr in the form of inorganic mercury compounds. As for As, Be, Co, Cr, Fe, Ge, Ir, Mo, Nb, Os, Pt, Re, Ru, Se, Ta, V, W and Zr, precipitation could be occurred when increasing the amounts of spallation products with operation time of the spallation target system. On the other hand, beryllium-7 (Be-7), which is produced by spallation reaction of oxygen in the cooling water of a safety hull, becomes the main factor of the external exposure to maintain the cooling loop. Based on the thermochemical equilibrium calculation to Be-H 2 O binary system, the chemical forms of Be in the cooling water were estimated. Then the Be could exist in the form of cations such as BeOH + , BeO + and Be 2+ under the condition of less than 10 -8 of the Be mole fraction in the cooling water. (author)

  2. Cross section measurement of residues produced in proton- and deuteron-induced spallation reactions on 93Zr at 105 MeV/u using the inverse kinematics method

    Directory of Open Access Journals (Sweden)

    Kawase Shoichiro

    2017-01-01

    Full Text Available Isotopic production cross sections in the proton- and deuteron-induced spallation reactions on 93Zr at an energy of 105 MeV/u were measured in inverse kinematics conditions for the development of realistic nuclear transmutation processes for long-lived fission products (LLFPs with neutron and light-ion beams. The experimental results were compared to the PHITS calculations describing the intra-nuclear cascade and evaporation processes. Although an overall agreement was obtained, a large overestimation of the production cross sections for the removal of a few nucleons was seen. A clear shell effect associated with the neutron magic number N = 50 was observed in the measured isotopic production yields of Zr and Y isotopes, which can be reproduced reasonably by the PHITS calculation.

  3. Pulsed spallation Neutron Sources

    International Nuclear Information System (INIS)

    Carpenter, J.M.

    1994-01-01

    This paper reviews the early history of pulsed spallation neutron source development at Argonne and provides an overview of existing sources world wide. A number of proposals for machines more powerful than currently exist are under development, which are briefly described. The author reviews the status of the Intense Pulsed Neutron Source, its instrumentation, and its user program, and provides a few examples of applications in fundamental condensed matter physics, materials science and technology

  4. Pulsed spallation neutron sources

    International Nuclear Information System (INIS)

    Carpenter, J.M.

    1996-01-01

    This paper reviews the early history of pulsed spallation neutron source development ar Argonne and provides an overview of existing sources world wide. A number of proposals for machines more powerful than currently exist are under development, which are briefly described. The author reviews the status of the Intense Pulsed Neutron Source, its instrumentation, and its user program, and provide a few examples of applications in fundamental condensed matter physics, materials science and technology

  5. Delayed neutrons in liquid metal spallation targets

    International Nuclear Information System (INIS)

    Ridikas, D.; Bokov, P.; David, J.C.; Dore, D.; Giacri, M.L.; Van Lauwe, A.; Plukiene, R.; Plukis, A.; Ignatiev, S.; Pankratov, D.

    2003-01-01

    The next generation spallation neutron sources, neutrino factories or RIB production facilities currently being designed and constructed around the world will increase the average proton beam power on target by a few orders of magnitude. Increased proton beam power results in target thermal hydraulic issues leading to new target designs, very often based on flowing liquid metal targets such as Hg, Pb, Pb-Bi. Radioactive nuclides produced in liquid metal targets are transported into hot cells, past electronics, into pumps with radiation sensitive components, etc. Besides the considerable amount of photon activity in the irradiated liquid metal, a significant amount of the delayed neutron precursor activity can be accumulated in the target fluid. The transit time from the front of a liquid metal target into areas, where delayed neutrons may be important, can be as short as a few seconds, well within one half-life of many delayed neutron precursors. Therefore, it is necessary to evaluate the total neutron flux (including delayed neutrons) as a function of time and determine if delayed neutrons contribute significantly to the dose rate. In this study the multi-particle transport code MCNPX combined with the material evolution program CINDER'90 will be used to evaluate the delayed neutron flux and spectra. The following scientific issues will be addressed in this paper: - Modeling of a typical geometry of the liquid metal spallation target; - Predictions of the prompt neutron fluxes, fission fragment and spallation product distributions; - Comparison of the above parameters with existing experimental data; - Time-dependent calculations of delayed neutron precursors; - Neutron flux estimates due to the prompt and delayed neutron emission; - Proposal of an experimental program to measure delayed neutron spectra from high energy spallation-fission reactions. The results of this study should be directly applicable in the design study of the European MegaPie (1 MW

  6. Shielding concerns at a spallation source

    International Nuclear Information System (INIS)

    Russell, G.J.; Robinson, H.; Legate, G.L.; Woods, R.

    1989-01-01

    Neutrons produced by 800-MeV proton reactions at the Los Alamos Neutron Scattering Center spallation neutron source cause a variety of challenging shielding problems. We identify several characteristics distinctly different from reactor shielding and compute the dose attenuation through an infinite slab/shield composed of iron (100 cm) and borated polyethylene (15 cm). Our calculations show that (for an incident spallation spectrum characteristic of neutrons leaking from a tungsten target at 90/degree/) the dose through the shield is a complex mixture of neutrons and gamma rays. High-energy (> 20 MeV) neutron production from the target is ≅5% of the total, yet causes ≅68% of the dose at the shield surface. Primary low-energy (< 20 MeV) neutrons from the target contribute negligibly (≅0.5%) to the dose at the shield surface yet cause gamma rays, which contribute ≅31% to the total dose at the shield surface. Low-energy neutrons from spallation reactions behave similarly to neutrons with a fission spectrum distribution. 6 refs., 8 figs., 1 tab

  7. Neutronics of pulsed spallation neutron sources

    CERN Document Server

    Watanabe, N

    2003-01-01

    Various topics and issues on the neutronics of pulsed spallation neutron sources, mainly for neutron scattering experiments, are reviewed to give a wide circle of readers a better understanding of these sources in order to achieve a high neutronic performance. Starting from what neutrons are needed, what the spallation reaction is and how to produce slow-neutrons more efficiently, the outline of the target and moderator neutronics are explained. Various efforts with some new concepts or ideas have already been devoted to obtaining the highest possible slow-neutron intensity with desired pulse characteristics. This paper also reviews the recent progress of such efforts, mainly focused on moderator neutronics, since moderators are the final devices of a neutron source, which determine the source performance. Various governing parameters for neutron-pulse characteristics such as material issues, geometrical parameters (shape and dimensions), the target-moderator coupling scheme, the ortho-para-hydrogen ratio, po...

  8. Spallation neutrons pulsed sources

    International Nuclear Information System (INIS)

    Carpenter, J.

    1996-01-01

    This article describes the range of scientific applications which can use these pulsed neutrons sources: Studies on super fluids, measures to verify the crawling model for the polymers diffusion; these sources are also useful to study the neutron disintegration, the ultra cold neutrons. In certain applications which were not accessible by neutrons diffusion, for example, radiations damages, radionuclides production and activation analysis, the spallation sources find their use and their improvement will bring new possibilities. Among others contributions, one must notice the place at disposal of pulsed muons sources and neutrinos sources. (N.C.). 3 figs

  9. Proton-induced fission of actinides at energies 26.5 and 62.9 MeV--Theoretical interpretation

    International Nuclear Information System (INIS)

    Demetriou, P.; Keutgen, Th.; Prieels, R.; El Masri, Y.

    2011-01-01

    Fission properties of proton-induced fission on 232 Th, 237 Np, 238 U, 239 Pu and 241 Am targets, measured at the Louvain-la-Neuve cyclotron facility at proton energies of 26.5 and 62.9 MeV, are compared with the predictions of the state-of-the-art nuclear reaction code TALYS. The sensitivity of the calculations to the input parameters of the code and possible improvements are discussed.

  10. Development of a nuclear spallation simulation code and calculations of primary spallation products

    International Nuclear Information System (INIS)

    Nishida, Takahiko; Nakahara, Yasuaki; Tsutsui, Tsuneo

    1986-08-01

    In order to make evaluations of computational models for the nuclear spallation reaction from a nuclear physics point of view, a simulation code NUCLEUS has been developed by modifying and combining the Monte Carlo codes NMTC/JAERI and NMTA/JAERI for calculating only the nuclear spallation reaction (intranuclear cascade + evaporation and/or fast fission) between a nucleus and a projectile without taking into consideration of internuclear transport. New several plotting routines have been provided for the rapid process of much more event data, obtained by using the ARGUS plotting system. The results obtained by our code can be directly compared with the experimental results using by thin foil experiments in which internuclear multiple collisions have little effects, and will serve to upgrade the calculational methods and the values of nuclear parameters currently used in the calculations. Some discussions are done about the preliminary computational results obtained by using NUCLEUS. The mass distribution and charge dispersion of reaction products are examined in some detail for the nuclear spallation reaction between incident protons and target nuclei, such as U, Pb and Ag, in the energy range from 0.5 GeV to 3.0 GeV. These results show that the distribution of reaction products ceases to change its form as the proton energy increases over about 2 GeV. The same tendency is seen in the energy dependence of the number of primary particles emitted from a nucleus. After spallation reactions, a variety of nuclei, especially many neutron deficient nuclides with nuclear charges nearly equal to ones of a target nucleus, are produced. Due to their short lifetime most of them will change to stable nuclides in due time. Finally, some important issues are discussed to improve the present simulation method. (author)

  11. Astrophysical Li-7 as a product of big bang nucleosynthesis and galactic cosmic-ray spallation

    Science.gov (United States)

    Olive, Keith A.; Schramm, David N.

    1992-01-01

    The astrophysical Li-7 abundance is considered to be largely primordial, while the Be and B abundances are thought to be due to galactic cosmic ray (GCR) spallation reactions on top of a much smaller big bang component. But GCR spallation should also produce Li-7. As a consistency check on the combination of big bang nucleosynthesis and GCR spallation, the Be and B data from a sample of hot population II stars is used to subtract from the measured Li-7 abundance an estimate of the amount generated by GCR spallation for each star in the sample, and then to add to this baseline an estimate of the metallicity-dependent augmentation of Li-7 due to spallation. The singly reduced primordial Li-7 abundance is still consistent with big bang nucleosynthesis, and a single GCR spallation model can fit the Be, B, and corrected Li-7 abundances for all the stars in the sample.

  12. Cross sections and kinematics of proton induced fragmentation of carbon

    International Nuclear Information System (INIS)

    Streibel, T.; Roecher, H.; Huentrup, G.; Heinrich, W.

    1997-01-01

    Charge changing fragmentation cross sections for C at a proton energy of about 70 MeV were measured. The discrepancies between measurement and model predictions indicate the necessity of further investigations. We have also measured distributions of fragment emission angles which can be described using a model with a momentum transfer to the fragmenting nucleus. The developed model leads to predictions for momentum distributions of proton induced target fragments of C at small energies. (orig.)

  13. Actin-cytoskeleton rearrangement modulates proton-induced uptake

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Dov, Nadav [Department of Physiology and Pharmacology, Faculty of Medicine, Tel-Aviv University, 69978 Tel-Aviv (Israel); Korenstein, Rafi, E-mail: korens@post.tau.ac.il [Department of Physiology and Pharmacology, Faculty of Medicine, Tel-Aviv University, 69978 Tel-Aviv (Israel)

    2013-04-15

    Recently it has been shown that elevating proton concentration at the cell surface stimulates the formation of membrane invaginations and vesicles accompanied by an enhanced uptake of macromolecules. While the initial induction of inward membrane curvature was rationalized in terms of proton-based increase of charge asymmetry across the membrane, the mechanisms underlying vesicle formation and its scission are still unknown. In light of the critical role of actin in vesicle formation during endocytosis, the present study addresses the involvement of cytoskeletal actin in proton-induced uptake (PIU). The uptake of dextran-FITC is used as a measure for the factual fraction of inward invaginations that undergo scission from the cell's plasma membrane. Our findings show that the rate of PIU in suspended cells is constant, whereas the rate of PIU in adherent cells is gradually increased in time, saturating at the level possessed by suspended cells. This is consistent with pH induced gradual degradation of stress-fibers in adherent cells. Wortmannin and calyculin-A are able to elevate PIU by 25% in adherent cells but not in suspended cells, while cytochalasin-D, rapamycin and latrunculin-A elevate PIU both in adherent and suspended cells. However, extensive actin depolymerization by high concentrations of latrunculin-A is able to inhibit PIU. We conclude that proton-induced membrane vesiculation is restricted by the actin structural resistance to the plasma membrane bending. Nevertheless, a certain degree of cortical actin restructuring is required for the completion of the scission process. - Highlights: ► Acidification of cells' exterior enhances uptake of macromolecules by the cells. ► Disruption of actin stress fibers leads to enhancement of proton induced uptake. ► Extensive depolymerization of cellular actin attenuates proton-induced uptake.

  14. Cross sections and kinematics of proton induced fragmentation of carbon

    Energy Technology Data Exchange (ETDEWEB)

    Streibel, T; Roecher, H; Huentrup, G; Heinrich, W [Siegen Univ. (Germany). Dept. of Physics

    1997-09-01

    Charge changing fragmentation cross sections for C at a proton energy of about 70 MeV were measured. The discrepancies between measurement and model predictions indicate the necessity of further investigations. We have also measured distributions of fragment emission angles which can be described using a model with a momentum transfer to the fragmenting nucleus. The developed model leads to predictions for momentum distributions of proton induced target fragments of C at small energies. (orig.)

  15. Detection of supernova neutrinos at spallation neutron sources

    Science.gov (United States)

    Huang, Ming-Yang; Guo, Xin-Heng; Young, Bing-Lin

    2016-07-01

    After considering supernova shock effects, Mikheyev-Smirnov-Wolfenstein effects, neutrino collective effects, and Earth matter effects, the detection of supernova neutrinos at the China Spallation Neutron Source is studied and the expected numbers of different flavor supernova neutrinos observed through various reaction channels are calculated with the neutrino energy spectra described by the Fermi-Dirac distribution and the “beta fit” distribution respectively. Furthermore, the numerical calculation method of supernova neutrino detection on Earth is applied to some other spallation neutron sources, and the total expected numbers of supernova neutrinos observed through different reactions channels are given. Supported by National Natural Science Foundation of China (11205185, 11175020, 11275025, 11575023)

  16. Neutronics of pulsed spallation neutron sources

    International Nuclear Information System (INIS)

    Watanabe, Noboru

    2003-01-01

    Various topics and issues on the neutronics of pulsed spallation neutron sources, mainly for neutron scattering experiments, are reviewed to give a wide circle of readers a better understanding of these sources in order to achieve a high neutronic performance. Starting from what neutrons are needed, what the spallation reaction is and how to produce slow-neutrons more efficiently, the outline of the target and moderator neutronics are explained. Various efforts with some new concepts or ideas have already been devoted to obtaining the highest possible slow-neutron intensity with desired pulse characteristics. This paper also reviews the recent progress of such efforts, mainly focused on moderator neutronics, since moderators are the final devices of a neutron source, which determine the source performance. Various governing parameters for neutron-pulse characteristics such as material issues, geometrical parameters (shape and dimensions), the target-moderator coupling scheme, the ortho-para-hydrogen ratio, poisoning, etc are discussed, aiming at a high performance pulsed spallation source

  17. Structural materials for fusion and spallation sources

    International Nuclear Information System (INIS)

    Cottrell, G.A.; Baker, L.J.

    2003-01-01

    Experimental investigation of neutron-induced irradiation damage in structural materials is fundamental to the development of magnetic confinement fusion. Proposals for the testing of candidate materials are described, indicating that a period of at least 10 years will elapse before a suitable high neutron fluence fusion test facility becomes available. In this circumstance, the possibility that neutron spallation sources could be exploited to shorten the time-scale of fusion materials development is attractive. Although fusion displacement and transmutation reaction rates can be replicated in spallation sources, there are significant differences arising from the harder neutron spectra and the presence of energetic protons. These differences, including higher energy PKA, electron heating effects, transmutation rates and pulsing are described and their consequences discussed, together with the concomitant development of theoretical models, needed to understand the effects. It is concluded that spallation source experiments could make a significant contribution to the database required for the validation of theoretical models, and hence reduce the time scale of fusion materials development

  18. Outline of spallation neutron source engineering

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Noboru [Center for Neutron Science, Tokai Research Establishment, Japan Atomic Energy Research Institute, Tokai, Ibaraki (Japan)

    2001-01-01

    Slow neutrons such as cold and thermal neutrons are unique probes which can determine structures and dynamics of condensed matter in atomic scale. The neutron scattering technique is indispensable not only for basic sciences such as condensed matter research and life science, but also for basic industrial technology in 21 century. It is believed that to survive in the science-technology competition in 21 century would be almost impossible without neutron scattering. However, the intensity of neutrons presently available is much lower than synchrotron radiation sources, etc. Thus, R and D of intense neutron sources become most important. The High-Intensity Proton Accelerator Project is now being promoted jointly by Japan Atomic Energy Research Institute and High Energy Accelerator Research Organization, but there has so far been no good text which covers all the aspects of pulsed spallation neutron sources. The present review was prepare aiming at giving a better understanding on pulsed spallation neutron sources not only to neutron source researchers but also more widely to neutron scattering researchers and accelerator scientists in this field. The contents involve, starting from what is neutron scattering and what neutrons are necessary for neutron scattering, what is the spallation reaction, how to produce neutrons required for neutron scattering more efficiently, target-moderator-reflector neutronics and its engineering, shielding, target station, material issues, etc. The author have engaged in R and D of pulsed apallation neutron sources and neutron scattering research using them over 30 years. The present review is prepared based on the author's experiences with useful information obtained through ICANS collaboration and recent data from the JSNS (Japanese Spallation Neutron Source) design team. (author)

  19. Nuclear reaction models - source term estimation for safety design in accelerators

    International Nuclear Information System (INIS)

    Nandy, Maitreyee

    2013-01-01

    Accelerator driven subcritical system (ADSS) employs proton induced spallation reaction at a few GeV. Safety design of these systems involves source term estimation in two steps - multiple fragmentation of the target and n+γ emission through a fast process followed by statistical decay of the primary fragments. The prompt radiation field is estimated in the framework of quantum molecular dynamics (QMD) theory, intra-nuclear cascade or Monte Carlo calculations. A few nuclear reaction model codes used for this purpose are QMD, JQMD, Bertini, INCL4, PHITS, followed by statistical decay codes like ABLA, GEM, GEMINI, etc. In the case of electron accelerators photons and photoneutrons dominate the prompt radiation field. High energy photon yield through Bremsstrahlung is estimated in the framework of Born approximation while photoneutron production is calculated using giant dipole resonance and quasi-deuteron formation cross section. In this talk hybrid and exciton PEQ models and QMD formalism will be discussed briefly

  20. Spallation neutron spectra measured at Saturne

    International Nuclear Information System (INIS)

    Boyard, J.L.; Bouyer, P.; Brochard, F.; Duchazeaubeneix, J.C.; Durand, J.M.; Leray, S.; Milleret, G.; Plouin, F.; Uematsu, M.; Whittal, D.M.; Martinez, E.; Beau, M.; Boue, F.; Crespin, S.; Drake, D.; Frehaut, J.; Lochard, J.P.; Patin, Y.; Petibon, E.; Legrain, R.; Terrien, Y.

    1995-01-01

    Good knowledge of spallation reactions is necessary to design accelerator-based transmutation systems. An extensive program has begun at Saturne to measure energy and angular distributions of neutrons produced by incident protons or deuterons of up to 2 GeV on several thin targets. Our measurements will extend the available data to higher energies than the present limit of 800 MeV enabling improvements to the codes which are sometimes in poor agreement with the data. (Authors). 7 refs., 7 figs

  1. Development of nuclear design criteria for neutron spallation sources

    Energy Technology Data Exchange (ETDEWEB)

    Sordo, F.; Abanades, A. [E.T.S. Industriales, Madrid Polytechnic University, UPM, J.Gutierrez Abascal, 2 -28006 Madrid (Spain)

    2008-07-01

    Spallation neutron sources allow obtaining high neutronic flux for many scientific and industrial applications. In recent years, several proposals have been made about its use, notably the European Spallation Source (ESS), the Japanese Spallation Source (JSNS) and the projects of Accelerator-Driven Subcritical reactors (ADS), particularly in the framework of EURATOM programs. Given their interest, it seems necessary to establish adequate design basis for guiding the engineering analysis and construction projects of this kind of installations. In this sense, all works done so far seek to obtain particular solutions to a particular design, but there has not been any general development to set up an engineering methodology in this field. In the integral design of a spallation source, all relevant physical processes that may influence its behaviour must be taken into account. Neutronic aspects (emitted neutrons and their spectrum, generation performance..), thermomechanical (energy deposition, cooling conditions, stress distribution..), radiological (spallation waste activity, activation reactions and residual heat) and material properties alteration due to irradiation (atomic displacements and gas generation) must all be considered. After analysing in a systematic manner the different options available in scientific literature, the main objective of this thesis was established as making a significant contribution to determine the limiting factors of the main aspects of spallation sources, its application range and the criteria for choosing optimal materials. To achieve this goal, a series of general simulations have been completed, covering all the relevant physical processes in the neutronic and thermal-mechanical field. Finally, the obtained criteria have been applied to the particular case of the design of the spallation source of subcritical reactors PDX-ADS and XT-ADS. These two designs, developed under the European R and D Framework Program, represent nowadays

  2. Development of nuclear design criteria for neutron spallation sources

    International Nuclear Information System (INIS)

    Sordo, F.; Abanades, A.

    2008-01-01

    Spallation neutron sources allow obtaining high neutronic flux for many scientific and industrial applications. In recent years, several proposals have been made about its use, notably the European Spallation Source (ESS), the Japanese Spallation Source (JSNS) and the projects of Accelerator-Driven Subcritical reactors (ADS), particularly in the framework of EURATOM programs. Given their interest, it seems necessary to establish adequate design basis for guiding the engineering analysis and construction projects of this kind of installations. In this sense, all works done so far seek to obtain particular solutions to a particular design, but there has not been any general development to set up an engineering methodology in this field. In the integral design of a spallation source, all relevant physical processes that may influence its behaviour must be taken into account. Neutronic aspects (emitted neutrons and their spectrum, generation performance..), thermomechanical (energy deposition, cooling conditions, stress distribution..), radiological (spallation waste activity, activation reactions and residual heat) and material properties alteration due to irradiation (atomic displacements and gas generation) must all be considered. After analysing in a systematic manner the different options available in scientific literature, the main objective of this thesis was established as making a significant contribution to determine the limiting factors of the main aspects of spallation sources, its application range and the criteria for choosing optimal materials. To achieve this goal, a series of general simulations have been completed, covering all the relevant physical processes in the neutronic and thermal-mechanical field. Finally, the obtained criteria have been applied to the particular case of the design of the spallation source of subcritical reactors PDX-ADS and XT-ADS. These two designs, developed under the European R and D Framework Program, represent nowadays

  3. Analysis of sludge using Proton induced X-ray emission

    International Nuclear Information System (INIS)

    Aspiazu, J.; Moreno, E.; Andrade, E.; Miranda, J.; Citalan, S.; Moeller, G.; Soler, F.

    1996-01-01

    Regulations to control the huge amounts of sludge produced by wastewater are needed. Sludge generated in conventional sedimentators or anaerobic digesters were characterized by Proton Induced X-ray Emission (PIXE). It was possible to determine the presence of macro nutrient elements, such as P and K, and secondary nutrients like Ca, S, and Mg. Moreover, heavy elements like Cu, Zn, and Pb were also found. The sludge treatment in anaerobic digesters increased the amount of certain elements Al, Si, S, Cl, and K; decrease in Ca, Ti, and Cu, and no change in V, Cr, and Zn. Possible uses of this sludge are also suggested

  4. EXPERIMENTAL ANALYSES OF SPALLATION NEUTRONS GENERATED BY 100 MEV PROTONS AT THE KYOTO UNIVERSITY CRITICAL ASSEMBLY

    Directory of Open Access Journals (Sweden)

    CHEOL HO PYEON

    2013-02-01

    Full Text Available Neutron spectrum analyses of spallation neutrons are conducted in the accelerator-driven system (ADS facility at the Kyoto University Critical Assembly (KUCA. High-energy protons (100 MeV obtained from the fixed field alternating gradient accelerator are injected onto a tungsten target, whereby the spallation neutrons are generated. For neutronic characteristics of spallation neutrons, the reaction rates and the continuous energy distribution of spallation neutrons are measured by the foil activation method and by an organic liquid scintillator, respectively. Numerical calculations are executed by MCNPX with JENDL/HE-2007 and ENDF/B-VI libraries to evaluate the reaction rates of activation foils (bismuth and indium set at the target and the continuous energy distribution of spallation neutrons set in front of the target. For the reaction rates by the foil activation method, the C/E values between the experiments and the calculations are found around a relative difference of 10%, except for some reactions. For continuous energy distribution by the organic liquid scintillator, the spallation neutrons are observed up to 45 MeV. From these results, the neutron spectrum information on the spallation neutrons generated at the target are attained successfully in injecting 100 MeV protons onto the tungsten target.

  5. On the role of secondary pions in spallation targets

    Energy Technology Data Exchange (ETDEWEB)

    Mancusi, Davide [Paris-Saclay Univ., Gif-sur-Yvette (France). Den-Service d' Etude des Reacteurs et de Mathematiques Appliquees (SERMA); Lo Meo, Sergio [ENEA, Research Centre ' ' Ezio Clementel' ' , Bologna (Italy); INFN, Bologna (Italy); Colonna, Nicola [INFN, Bari (Italy); Boudard, Alain; David, Jean-Christophe; Leray, Sylvie [Paris-Saclay Univ., Gif-sur-Yvette (France). IRFU, CEA; Cortes-Giraldo, Miguel Antonio; Lerendegui-Marco, Jorge [Sevilla Univ. (Spain). Facultad de Fisica; Cugnon, Joseph [Liege Univ. (Belgium). AGO Dept.; Massimi, Cristian [INFN, Bologna (Italy); Bologna Univ. (Italy). Physics and Astronomy Dept.; Vlachoudis, Vasilis [European Organization for Nuclear Research (CERN), Geneva (Switzerland)

    2017-05-15

    We use particle-transport simulations to show that secondary pions play a crucial role for the development of the hadronic cascade and therefore for the production of neutrons and photons from thick spallation targets. In particular, for the nTOF lead spallation target, irradiated with 20 GeV/c protons, neutral pions are involved in the production of ∝ 90% of the high-energy photons; charged pions participate in ∝ 40% of the integral neutron yield. Nevertheless, photon and neutron yields are shown to be relatively insensitive to large changes of the average pion multiplicity in the individual spallation reactions. We characterize this robustness as a peculiar property of hadronic cascades in thick targets. (orig.)

  6. On the role of secondary pions in spallation targets

    CERN Document Server

    Mancusi, Davide; Colonna, Nicola; Boudard, Alain; Cortés-Giraldo, Miguel Antonio; Cugnon, Joseph; David, Jean-Christophe; Leray, Sylvie; Lerendegui-Marco, Jorge; Massimi, Cristian; Vlachoudis, Vasilis

    2017-01-01

    We use particle-transport simulations to show that secondary pions play a crucial role for the development of the hadronic cascade and therefore for the production of neutrons and photons from thick spallation targets. In particular, for the n_TOF lead spallation target, irradiated with 20-GeV/c protons, neutral pions are involved in the production of ~90% of the high-energy photons; charged pions participate in ~40% of the integral neutron yield. Nevertheless, photon and neutron yields are shown to be relatively insensitive to large changes of the average pion multiplicity in the individual spallation reactions. We characterize this robustness as a peculiar property of hadronic cascades in thick targets.

  7. Photon and proton induced fission on heavy nuclei at intermediate energies

    Directory of Open Access Journals (Sweden)

    Andrade-II E.

    2014-04-01

    Full Text Available We present an analysis of fission induced by intermediate energy protons or photons on actinides. The 660 MeV proton induced reactions are on 241Am, 238U, and 237Np targets and the Bremmstrahlung-photons with end-point energies at 50 MeV and 3500 MeV are on 232Th and 238U targets. The study was performed by means of the Monte Carlo simulation code CRISP. A multimodal fission extension was added to the code within an approach which accounts for the contribution of symmetric and asymmetric fission. This procedure allowed the investigation of fission cross sections, fissility, number of evaporated nucleons and fission-fragment charge distributions. The comparison with experimental data show a good agreement between calculations and experiments.

  8. Photon and proton induced fission on heavy nuclei at intermediate energies

    Energy Technology Data Exchange (ETDEWEB)

    Andrade-II, E.; Karapetyan, G.S.; Deppman, A.; Guimaraes, V. [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Instituto de Fisica; Balabekyan, A.R. [Yerevan State University, Alex Manoogian 1, Yerevan (Armenia); Demekhina, N.A. [Yerevan Physics Institute, Alikhanyan Brothers 2, Yerevan (Armenia); Joint Institute for Nuclear Research (JINR), Flerov Laboratory of Nuclear Reactions (LNR), Moscow (Russian Federation)

    2014-07-01

    We present an analysis of fission induced by intermediate energy protons or photons on actinides. The 660 MeV proton induced reactions are on {sup 241}Am, {sup 238}U, and {sup 237}Np targets and the Bremsstrahlung-photons with end-point energies at 50 MeV and 3500 MeV are on {sup 232}Th and {sup 238}U targets. The study was performed by means of the Monte Carlo simulation code CRISP. A multimodal fission extension was added to the code within an approach which accounts for the contribution of symmetric and asymmetric fission. This procedure allowed the investigation of fission cross sections, fissility, number of evaporated nucleons and fission-fragment charge distributions. The comparison with experimental data show a good agreement between calculations and experiments. (author)

  9. Introduction to spallation physics and spallation-target design

    Energy Technology Data Exchange (ETDEWEB)

    Russell, G.J.; Pitcher, E.J.; Daemen, L.L. [Los Alamos National Laboratory, NM (United States)

    1995-10-01

    When coupled with the spallation process in appropriate target materials, high-power accelerators can be used to produce large numbers of neutrons, thus providing an alternate method to the use of nuclear reactors for this purpose. Spallation offers exciting new possibilities for generating intense neutron fluxes for a variety of applications, including: (a) spallation-neutron sources for materials science research; (b) accelerator-based production of tritium; (c) accelerator-based transmutation of waste; (d) accelerator-based destruction of plutonium; and (e) radioisotope production for medical and energy applications. Target design plays a key role in these applications, with neutron production/leakage being strongly dependent on the incident particle type and energy, and target material and geometry.

  10. Spallation source neutron target systems

    International Nuclear Information System (INIS)

    Russell, G.; Brown, R.; Collier, M.; Donahue, J.

    1996-01-01

    This is the final report for a two-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project sought to design a next-generation spallation source neutron target system for the Manuel Lujan, Jr., Neutron Scattering Center (LANSCE) at Los Alamos. It has been recognized for some time that new advanced neutron sources are needed in the US if the country is to maintain a competitive position in several important scientific and technological areas. A recent DOE panel concluded that the proposed Advanced Neutron Source (a nuclear reactor at Oak Ridge National Laboratory) and a high-power pulsed spallation source are both needed in the near future. One of the most technically challenging designs for a spallation source is the target station itself and, more specifically, the target-moderator-reflector arrangement. Los Alamos has demonstrated capabilities in designing, building, and operating high-power spallation-neutron-source target stations. Most of the new design ideas proposed worldwide for target system design for the next generation pulsed spallation source have either been conceived and implemented at LANSCE or proposed by LANSCE target system designers. These concepts include split targets, flux-trap moderators, back scattering and composite moderators, and composite reflectors

  11. Study of the spallation reactions 136Xe + p and 136Xe + 12C at 1 GeV per nucleon at the GSI facility (Darmstadt, Germany)

    International Nuclear Information System (INIS)

    Gorbinet, T.

    2011-11-01

    The collision of 136 Xe with a proton and with 12 C at 1 GeV per nucleon of projectile kinetic energy in the center of mass has been studied in inverse kinematics using the SPALADIN experimental setup at the GSI facility. This manuscript describes the analysis of these collisions realized in spring 2009. The detection in coincidence of the final state fragments (projectile residues, neutrons and light charged fragments) with a large geometrical efficiency is provided by the inverse kinematics combined with a large aperture dipole magnet and large detectors. Such a coincidence, measured on an event basis, allows selecting, in a model independent way, the pre-fragment, the excited nuclear system formed after the intranuclear cascade as a function of its excitation energy. Hence, we were able to study the evolution of the pre-fragment deexcitation mechanism (evaporation of light particles, asymmetric binary decay, multiple fragmentation..) as a function of its excitation energy. The data of the 136 Xe + p reaction have been compared mainly to three deexcitation models (SMM, GEMINI++ and ABLA07) coupled to the intranuclear cascade code INCL4. Despite the relatively good and global agreement between these models and our data, significant discrepancies appeared concerning in particular the production of intermediate mass fragments (IMF). Comparison between the 136 Xe + 12 C and the 136 Xe + p data exhibits an important similarity in the deexcitation of the pre-fragments. This suggests that the nuclear cascade leads, for both targets, to similar pre-fragment types in the range of excitation energy (0 to 4 MeV per nucleon) common to both reactions. Higher excitation energies, reached only in the 136 Xe + 12 C reaction, show a qualitative difference in the deexcitation of the pre-fragment, with much higher multiplicities of IMF per event, increasing with the excitation energy. (author)

  12. Study of nuclear reactions involving heavy nuclei and intermediate- and high-energy protons and an application in nuclear reactor physics (ADS); Estudo das reacoes nucleares envolvendo nucleos pesados e protons a energias intermediarias e altas de uma aplicacao em fisica de reatores nucleares (ADS)

    Energy Technology Data Exchange (ETDEWEB)

    Matuoka, Paula Fernanda Toledo

    2016-07-01

    In the present work, intermediate- and high-energy nuclear reactions involving heavy nuclei and protons were studied with the Monte Carlo CRISP (Rio - Ilheus - Sao Paulo Collaboration) model. The most relevant nuclear processes studied were intranuclear cascade and fission-evaporation competition. Preliminary studies showed fair agreement between CRISP model calculation and experimental data of multiplicity of evaporated neutrons (E < 20 MeV) from the p(1200 MeV) + {sup 208}Pb reaction and of spallation residues from the p(1000 MeV) + {sup 208}Pb reaction. The investigation of neutron multiplicity from proton-induced fission of {sup 232}Th up to 85 MeV showed that it was being overestimated by CRISP model; on the other hand, fission cross section were being underestimated. This behavior is due to limitations of the intranuclear cascade model for low-energies (around 50 MeV). The p(1200 MeV) + {sup 208}Pb reaction was selected for the study of a spallation neutron source. High-energy neutrons (E > 20 MeV) were emitted mostly in the intranuclear cascade stage, while evaporation presented larger neutron multiplicity. Fission cross section of 209 mb and spallation cross section of 1788 mb were calculated both in agreement with experimental data. The fission process resulted in a symmetric mass distribution. Another Monte Carlo code, MCNP, was used for radiation transport in order to understand the role of a spallation neutron source in a ADS (Accelerator Driven System) nuclear reactor. Initially, a PWR reactor was simulated to study the isotopic compositions in spent nuclear fuel. As a rst attempt, a spallation neutron source was adapted to an industrial size nuclear reactor. The results showed no evidence of incineration of transuranic elements and modifications were suggested. (author)

  13. Materials for spallation neutron sources

    International Nuclear Information System (INIS)

    Sommer, W.F.; Daemen, L.L.

    1996-03-01

    The Workshop on Materials for Spallation Neutron Sources at the Los Alamos Neutron Science Center, February 6 to 10, 1995, gathered scientists from Department of Energy national laboratories, other federal institutions, universities, and industry to discuss areas in which work is needed, successful designs and use of materials, and opportunities for further studies. During the first day of the workshop, speakers presented overviews of current spallation neutron sources. During the next 3 days, seven panels allowed speakers to present information on a variety of topics ranging from experimental and theoretical considerations on radiation damage to materials safety issues. An attempt was made to identify specific problems that require attention within the context of spallation neutron sources. This proceedings is a collection of summaries from the overview sessions and the panel presentations

  14. The spallation in reverse kinematics: what for a coincidence measurement?

    International Nuclear Information System (INIS)

    Ducret, J.E.

    2006-07-01

    The Spaladin installation has been designed to study spallation reactions in reverse kinematics. Furthermore, the heavy and light fragments are detected by coincidence which allows us to get an instantaneous picture of the reaction at a level of accuracy better than that obtained through inclusive measurement. The first part is dedicated to the theoretical description of the different mechanisms involved in the spallation reactions. In the second part we describe the Spaladin installation and report some results on the reaction: Fe 56 + p at an energy of 1 GeV/nucleon. In the third part we expose the performance of the installation through its simulation with the Geant-IV model. We present a study about the sensitivity of the Spaladin installation to theoretical predictions. The fourth part is dedicated to the future experiments that will be performed with the Spaladin installation. (A.C.)

  15. Potpourri of proton induced x-ray emission analyses

    International Nuclear Information System (INIS)

    Mangelson, N.F.; Nielson, K.K.; Eatough, D.J.; Hansen, L.D.

    1974-01-01

    A proton-induced x-ray emission analysis (PIXE) system using 2-MeV protons was developed. Measurements are being made in connection with several research projects. A study is being conducted to provide ecological baseline information in the region of the Navajo and the proposed Kaiparowits coal-fired electric generating stations. Trace-element measurements in this study are reported on air-particulate samples, small rodent tissues, soils, and plants. In another study air particulates collected near a source of SO 2 are extracted from the collection filter with an HCl solution and sulfate and sulfite ions are determined by calorimetric methods. The extraction solution is also analyzed by PIXE to determine the elemental composition. The latter information is necessary for an understanding of possible interferences with the calorimetric method and also indicates the heavy metals emitted by the source. Studies on human autopsy tissues, archeological artifacts, and in regular graduate and undergraduate laboratory classes are mentioned briefly

  16. Neutron and gamma-ray emission in the proton induced fission of {sup 238}U and {sup 242}Pu

    Energy Technology Data Exchange (ETDEWEB)

    Kniajeva, G.N.; Krupa, L.; Bogachev, A.A.; Chubarian, G.G.; Dorvaux, O.; Itkis, I.M.; Itkis, M.G.; Kliman, J.; Khlebnikov, S.; Kondratiev, N.A.; Kozulin, E.M.; Lyapin, V.; Materna, T.; Pokrovsky, I.V.; Rubchenya, V.A.; Trzaska, W.H.; Vakhtin, D.; Voskressenski, V.M

    2004-04-05

    Average prescission M{sup pre}{sub n} and postscission M{sup post}{sub n} neutron multiplicities as well as average {gamma}-ray multiplicity , average energy emitted by {gamma}-rays as a function of mass and total kinetic energy (TKE) of fission fragments were measured in proton induced reactions p+{sup 242}Pu{yields}{sup 243}Am, p+{sup 238}U{yields}{sup 239}Np at proton energy E{sub p}=13, 20 and 55 MeV.

  17. Status of spallation neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Oyama, Yukio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-03-01

    Existing and planned facilities using proton accelerator driven spallation neutron source are reviewed. These include new project of neutron science proposed from Japan Atomic Energy Research Institute. The present status of facility requirement and accelerator technology leads us to new era of neutron science such as neutron scattering research and nuclear transmutation study using very intense neutron source. (author)

  18. The proton-induced collinear deuteron breakup at 7.5 MeV

    International Nuclear Information System (INIS)

    Lekkas, P.

    1985-01-01

    The aim of the present thesis was to study the proton-induced deuteron breakup at an incident energy of 7.5 MeV in collinear geometry. In kinematically complete experiments in which two of the three particles of the exit channel are detected in coincidence we determined in equal kinematics the breakup cross section of the three-particle reactions 2 H(p,pp)n and 2 H(p,np)p. In both cases we observed in the region of the collinearity point an - indeed only weak - increasement of the cross section. The collinearity occurs in the neighbourhood of the QFS. Faddeev calculations with two different nucleon-nucleon interactions describe in the collinearity point the shape of the spectra well. Also the absolute quantity of the measured data in this point is well confirmed for the reaction 2 H(p,pp)n, less well however for the reaction 2 H(p,np)p. If in the theory three-nucleon forces are implemented their influence in the collinearity point is proved to be quantitatively weak. The collinear region is from the results of the present thesis especially because of the closely adjacent QFS little significant for three-body forces. (orig./HSI) [de

  19. Distribution of nuclear charge in the proton-induced fission of Th-232

    Energy Technology Data Exchange (ETDEWEB)

    Pate, B D [Brookhaven National Laboratory, Upton, New York (United States); Foster, J S; Yaffe, L [McGill Univ., Montreal, Quebec (Canada)

    1958-09-15

    A great deal of work has been done on the distribution of nuclear mass in the fission process. About the nuclear charge distribution less is known. Data exist on the distribution from the fission of U-235 with thermal neutrons and with 14 Mev neutrons. Data also exist for the fission of uranium by 170 Mev protons, of bismuth by 190 Mev deuterons, and of uranium, thorium and bismuth by 480 Mev protons, and there is fragmentary information from other systems. The present work was undertaken to investigate the changes that occur in the charge distribution from proton-induced fission of Th-232 as the bombarding energy is raised from 8 to 90 Mev, the maximum proton energy of the McGill synchrocyclotron. This energy range is of interest in view of the substantial changes observed in the mass distribution. Also in this interval a change presumably begins in the nature of the initial step in nuclear reactions, from simple compound-nucleus formation, to a mechanism of direct interaction with individual nucleons. Thus at the lower energies studied, excitation of the nuclei at the end of the first step of the reaction will be essentially monochromatic whereas at the higher end of the bombarding-energy range, a broad spectrum of excitation energies will be produced, with corresponding complexity of the reaction products observed. (author)

  20. Spallation reactions studied with 4 -detector arrays

    Indian Academy of Sciences (India)

    of inert or biological materials, these neutrons can be used to study details of the material ... ping zone- or neck-built up with part of projectile- and target-nuclei). ..... also been designed to complement the set of tools at our disposal [40].

  1. Proton induced fission of {sup 232}Th at intermediate energies

    Energy Technology Data Exchange (ETDEWEB)

    Gikal, K. B., E-mail: kgikal@mail.ru; Kozulin, E. M.; Bogachev, A. A. [JINR, Flerov Laboratory of Nuclear Reactions (Russian Federation); Burtebaev, N. T.; Edomskiy, A. V. [Institute of Nuclear Physics of Ministry of Energy of the Republic of Kazakhstan (Kazakhstan); Itkis, I. M.; Itkis, M. G.; Knyazhev, G. N. [JINR, Flerov Laboratory of Nuclear Reactions (Russian Federation); Kovalchuk, K. V.; Kvochkina, T. N. [Institute of Nuclear Physics of Ministry of Energy of the Republic of Kazakhstan (Kazakhstan); Piasecki, E. [Heavy Ion Laboratory of Warsaw University (Poland); Rubchenya, V. A. [University of Jyväskylä, Department of Physics (Finland); Sahiev, S. K. [Institute of Nuclear Physics of Ministry of Energy of the Republic of Kazakhstan (Kazakhstan); Trzaska, W. H. [University of Jyväskylä, Department of Physics (Finland); Vardaci, E. [INFN Napoli, Dipartimento di Scienze Fisiche dell’Università di Napoli (Italy)

    2016-12-15

    The mass-energy distributions and cross sections of proton-induced fission of {sup 232}Th have been measured at the proton energies of 7, 10, 13, 20, 40, and 55 MeV. Experiments were carried out at the proton beam of the K-130 cyclotron of the JYFL Accelerator Laboratory of the University of Jyväskylä and U-150m cyclotron of the Institute of Nuclear Physics, Ministry of Energy of the Republic of Kazakhstan. The yields of fission fragments in the mass range A = 60–170 a.m.u. have been measured up to the level of 10−4%. The three humped shape of the mass distribution up has been observed at higher proton energies. The contribution of the symmetric component grows up with increasing proton incident energy; although even at 55 MeV of proton energy the shoulders in the mass energy distribution clearly indicate the asymmetric fission peaks. Evolution of shell structure was observed in the fission fragment mass distributions even at high excitation energy.

  2. PIXE (proton induced X-ray emission) analysis of caatinger

    International Nuclear Information System (INIS)

    Nakanishi, T.M.; Futatsugawa, Shoji; Sera, Kouichiro.

    1995-01-01

    Caatinger (Mimosa acutistipula Benth), which has been a popular wood among the people in north east part of Brazil, was analyzed using PIXE (proton induced X-ray emission). The wood sample was divided into three parts, center, inner and outer side of the wood. Using the wood slice of each part, Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Mn, Fe, Cu, Zn, As, Se, Br, Rb, Sr, Y, Ru and Pb were detected. When the wood slices were decomposed with nitric acid, Co and Ni were able to be determined. Two samples, non-destructive and chemically treated sample, of heartwood and sapwood showed the similar concentration of the elements. There was a discrete change of the accumulated elements between heartwood and sapwood. Most of the elements detected tended to be concentrated at sapwood, whereas Ca, Cu and Sr were concentrated at heartwood. At center part, especially, Na, Mg, Fe and Sr were accumulated. Since most of the heartwood and sapwood is dead, discrete change of the element concentration suggests some element movement across the annual ring at heartwood formation. (author)

  3. Spallation neutron source moderator design

    International Nuclear Information System (INIS)

    Charlton, L.A.; Barnes, J.M.; Gabriel, T.A.; Johnson, J.O.

    1998-01-01

    This paper describes various aspects of the spallation neutron source (SNS) moderator design. Included are the effects of varying the moderator location, interaction effects between moderators, and the impact on neutron output when various reflector materials are used. Also included is a study of the neutron output from composite moderators, where it is found that a combination of liquid H 2 O and liquid H 2 can produce a spectrum very similar to liquid methane (L-CH 4 ). (orig.)

  4. Spallation Neutron Spectrum on a Massive Lead/Paraffin Target Irradiated with 1 GeV Protons

    CERN Document Server

    Adam, J; Barashenkov, V S; Brandt, R; Golovatiouk, V M; Kalinnikov, V G; Katovsky, K; Krivopustov, M I; Kumar, V; Kumawat, H; Odoj, R; Pronskikh, V S; Solnyshkin, A A; Stegailov, V I; Tsoupko-Sitnikov, V M; Westmeier, W

    2004-01-01

    The spectra of gamma-ray emitted by decaying residual nuclei, produced by spallation neutrons with (n, xn), (n,xnyp), (n,p), (n,gamma) reactions in activation threshold detectors - namely, ^{209}Bi, ^{197}Au, ^{59}Co, ^{115}In, ^{232}Th, were measured in the Laboratory of Nuclear Problems (LNP), JINR, Dubna, Russia. Spallation neutrons were generated by bombarding a 20 cm long cylindrical lead target, 8 cm in diameter, surrounded by a 6 cm thick layer of paraffin moderator, with a 1 GeV proton beam from the Nuclotron accelerator. Reaction rates and spallation neutron spectrum were measured and compared with CASCADE code calculations.

  5. Energy dependence of isotopic spectra from spallation residues

    International Nuclear Information System (INIS)

    Audouin, L.

    2003-09-01

    Spallation reactions are collisions between heavy nuclei and light particle with an energy of a few hundreds MeV. The y are considered as a suitable way to create high- flux neutrons sources, which may used for example for the transmutation of nuclear wastes (hybrid reactors). The study of the residues from such reactions is both a way to understand the physics of the spallation and to provide information required for the design of industrial targets. The residues from the spallation of lead by proton at 500 MeV have been measured using the inverse kinematics technique in the FRS (fragments recoil separator). spectrometer from GSI (Barmstadt). This low energy required the use of new technique, for the experimental setup as well as during the analysis. The fragments were identified in-flight, prior to β decay. Complete isotopic distributions are obtained with an accuracy ranging between 10 and 30%. Detailed information on the reaction kinematics are also obtained. Data are in excellent agreement with radio-chemical measurements, and bring new insights about the spallation process. The comparison with data measured on the same system with an incident energy of 1 GeV allows to discuss the influence of the projectile energy on the residues formation. It is concluded that the independence of the shape of the isobaric production cross sections regarding mass and energy of the projectile is preserved at low incident energies. The behaviour of Monte-Carlo codes is discussed with respect to those sets of data. The calculations show an improving agreement with decreasing energy, indicating that high-energy phenomena, for which some common assumptions become questionable, are the main reason for the observed discrepancies. (author)

  6. Analysis of proton-induced fragment production cross sections by the Quantum Molecular Dynamics plus Statistical Decay Model

    Energy Technology Data Exchange (ETDEWEB)

    Chiba, Satoshi; Iwamoto, Osamu; Fukahori, Tokio; Niita, Koji; Maruyama, Toshiki; Maruyama, Tomoyuki; Iwamoto, Akira [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-03-01

    The production cross sections of various fragments from proton-induced reactions on {sup 56}Fe and {sup 27}Al have been analyzed by the Quantum Molecular Dynamics (QMD) plus Statistical Decay Model (SDM). It was found that the mass and charge distributions calculated with and without the statistical decay have very different shapes. These results also depend strongly on the impact parameter, showing an importance of the dynamical treatment as realized by the QMD approach. The calculated results were compared with experimental data in the energy region from 50 MeV to 5 GeV. The QMD+SDM calculation could reproduce the production cross sections of the light clusters and intermediate-mass to heavy fragments in a good accuracy. The production cross section of {sup 7}Be was, however, underpredicted by approximately 2 orders of magnitude, showing the necessity of another reaction mechanism not taken into account in the present model. (author)

  7. Energy dependence of isotopic spectra from spallation residues; Dependance en energie des spectres isotopiques de residus de spallation

    Energy Technology Data Exchange (ETDEWEB)

    Audouin, L

    2003-09-01

    Spallation reactions are collisions between heavy nuclei and light particle with an energy of a few hundreds MeV. The y are considered as a suitable way to create high- flux neutrons sources, which may used for example for the transmutation of nuclear wastes (hybrid reactors). The study of the residues from such reactions is both a way to understand the physics of the spallation and to provide information required for the design of industrial targets. The residues from the spallation of lead by proton at 500 MeV have been measured using the inverse kinematics technique in the FRS (fragments recoil separator). spectrometer from GSI (Barmstadt). This low energy required the use of new technique, for the experimental setup as well as during the analysis. The fragments were identified in-flight, prior to {beta} decay. Complete isotopic distributions are obtained with an accuracy ranging between 10 and 30%. Detailed information on the reaction kinematics are also obtained. Data are in excellent agreement with radio-chemical measurements, and bring new insights about the spallation process. The comparison with data measured on the same system with an incident energy of 1 GeV allows to discuss the influence of the projectile energy on the residues formation. It is concluded that the independence of the shape of the isobaric production cross sections regarding mass and energy of the projectile is preserved at low incident energies. The behaviour of Monte-Carlo codes is discussed with respect to those sets of data. The calculations show an improving agreement with decreasing energy, indicating that high-energy phenomena, for which some common assumptions become questionable, are the main reason for the observed discrepancies. (author)

  8. Calculation of the spallation product distribution in the evaporation process

    International Nuclear Information System (INIS)

    Nishida, T.; Kanno, I.; Nakahara, Y.; Takada, H.

    1989-01-01

    Some investigations are performed for the calculational model of nuclear spallation reaction in the evaporation process. A new version of a spallation reaction simulation code NUCLEUS has been developed by incorporating the newly revised Uno ampersand Yamada's mass formula and extending the counting region of produced nuclei. The differences between the new and original mass formulas are shown in the comparisons of mass excess values. The distributions of spallation products of a uranium target nucleus bombarded by energy (0.38 - 2.9 GeV) protons have been calculated with the new and original versions of NUCLEUS. In the fission component Uno ampersand Yamada's mass formula reproduces the measured data obtained from thin foil experiments significantly better, especially in the neutron excess side, than the combination of the Cameron's mass formula and the mass table compiled by Wapstra, et al., in the original version of NUCLEUS. Discussions are also made on how the mass-yield distribution of products varies dependent on the level density parameter a characterizing the particle evaporation. 16 refs., 7 figs., 1 tab

  9. Calculation of the spallation product distribution in the evaporation process

    International Nuclear Information System (INIS)

    Nishida, T.; Kanno, I.; Nakahara, Y.; Takada, H.

    1989-01-01

    Some investigations are performed for the calculational model of nuclear spallation reaction in the evaporation process. A new version of a spallation reaction simulation code NUCLEUS has been developed by incorporating the newly revised Uno and Yamada's mass formula and extending the counting region of produced nuclei. The differences between the new and original mass formulas are shown in the comparisons of mass excess values. The distributions of spallation products of a uranium target nucleus bombarded by energy (0.38 - 2.9 GeV) protons have been calculated with the new and original versions of NUCLEUS. In the fission component Uno and Yamada's mass formula reproduces the measured data obtained from thin foil experiments significantly better, especially in the neutron excess side, than the combination of the Cameron's mass formula and the mass table compiled by Wapstra, et al., in the original version of NUCLEUS. Discussions are also made on how the mass-yield distribution of products varies dependent on the level density parameter α characterizing the particle evaporation. (author)

  10. Measured radionuclide production from copper, gold and lead spallation targets

    Energy Technology Data Exchange (ETDEWEB)

    Parish, T.A.; Belian, A.P. [Texas A & M Univ., College Station, TX (United States)

    1995-10-01

    Spallation target materials are chosen so as to produce large numbers of neutrons while at the same time avoiding the creation of long-lived radioactive wastes. While there has been considerable research to determine the number of neutrons produced per incident particle for various target materials, there has been less effort to precisely quantify the types and amounts of radionuclides produced. Accurate knowledge of the radioactive species produced by spallation reactions is important for specifying waste disposal criteria for targets. In order to verify the production rates calculated by LAHET, a study has been conducted using the Texas A&M University (TAMU) Cyclotron to measure radionuclide yields from copper, gold, and lead targets.

  11. AGS Spallation Target Experiment (ASTE) Collaboration

    International Nuclear Information System (INIS)

    Oyama, Yukio

    1999-01-01

    An experiment on mercury spallation target with high energy proton beam, called as the AGS Spallation Target Experiment (ASTE) Collaboration, has been performed at Alternating Gradient Synchrotron (AGS) of Brookhaven National Laboratory (BNL) in USA, in cooperation among the laboratories in Japan, Europe and USA. The experimental setup, scope and preliminary results are presented in the paper. (author)

  12. Spallator: a new option for nuclear power

    Energy Technology Data Exchange (ETDEWEB)

    Steinberg, M.; Grand, P.; Takahashi, H.; Powell, J.R.; Kouts, H.J.

    1983-06-01

    The principles of the spallator reactor are reviewed. Advances in linear accelerator technology allow the design and construction of high current (hundreds of mA) continuous wave high energy (thousands of MeV) proton machines in the near term. Spallation neutronic calculations building on existing experimental results, indicate substantial neutron yields on uranium targets. Spallator target assembly designs based on water cooled reactor technology indicate operable efficient systems. Fuel cycles are presented which supply fissile material to thermal power reactors and reduce fission product waste. Preliminary comparative analysis indicates an economically competitive system in which a single purpose self-sufficient spallator supplies fuel to a number of LWRs. The spallator assures a long-term LWR power reactor economy. International interest in advancing the technology is indicated.

  13. Spallator: a new option for nuclear power

    International Nuclear Information System (INIS)

    Steinberg, M.; Grand, P.; Takahashi, H.; Powell, J.R.; Kouts, H.J.

    1983-06-01

    The principles of the spallator reactor are reviewed. Advances in linear accelerator technology allow the design and construction of high current (hundreds of mA) continuous wave high energy (thousands of MeV) proton machines in the near term. Spallation neutronic calculations building on existing experimental results, indicate substantial neutron yields on uranium targets. Spallator target assembly designs based on water cooled reactor technology indicate operable efficient systems. Fuel cycles are presented which supply fissile material to thermal power reactors and reduce fission product waste. Preliminary comparative analysis indicates an economically competitive system in which a single purpose self-sufficient spallator supplies fuel to a number of LWRs. The spallator assures a long-term LWR power reactor economy. International interest in advancing the technology is indicated

  14. Nuclear spallation of cosmic ray nuclei in the interstellar medium

    International Nuclear Information System (INIS)

    Raisbeck, G.

    1974-01-01

    Nuclear spallation of cosmic rays during propagation is qualitatively reviewed. After the problem is defined, a discussion is presented of the relevant information obtainable from studying nuclear reactions, specifically, quantity and distribution of traversed matter, time and place of propagation, and source composition. Comments are offered on the cross sections and nuclear reactions that are critical for a complete understanding in this area. This is followed by a brief look at the present status of research and possibilities for further work using the Bevalac. (U.S.)

  15. Measurement of nuclide cross-sections of spallation residues in 1 A GeV 238U + proton collisions

    International Nuclear Information System (INIS)

    Taieb, J.; Tassan-Got, L.; Bernas, M.; Mustapha, B.; Rejmund, F.; Stephan, C.; Schmidt, K.H.; Armbruster, P.; Benlliure, J.; Enqvist, T.; Boudard, A.; Legrain, R.; Leray, S.; Volant, C.; Wlazlo, W.; Casarejos, E.; Czajkowski, S.; Pravikoff, M.

    2003-02-01

    The production of heavy nuclides from the spallation-evaporation reaction of 238 U induced by 1 GeV protons was studied in inverse kinematics. The evaporation residues from tungsten to uranium were identified in-flight in mass and atomic number. Their production cross-sections and their momentum distributions were determined. The data are compared with empirical systematics. A comparison with previous results from the spallation of 208 Pb and 197 Au reveals the strong influence of fission in the spallation of 238 U. (orig.)

  16. GEM-based thermal neutron beam monitors for spallation sources

    International Nuclear Information System (INIS)

    Croci, G.; Claps, G.; Caniello, R.; Cazzaniga, C.; Grosso, G.; Murtas, F.; Tardocchi, M.; Vassallo, E.; Gorini, G.; Horstmann, C.; Kampmann, R.; Nowak, G.; Stoermer, M.

    2013-01-01

    The development of new large area and high flux thermal neutron detectors for future neutron spallation sources, like the European Spallation Source (ESS) is motivated by the problem of 3 He shortage. In the framework of the development of ESS, GEM (Gas Electron Multiplier) is one of the detector technologies that are being explored as thermal neutron sensors. A first prototype of GEM-based thermal neutron beam monitor (bGEM) has been built during 2012. The bGEM is a triple GEM gaseous detector equipped with an aluminum cathode coated by 1μm thick B 4 C layer used to convert thermal neutrons to charged particles through the 10 B(n, 7 Li)α nuclear reaction. This paper describes the results obtained by testing a bGEM detector at the ISIS spallation source on the VESUVIO beamline. Beam profiles (FWHM x =31 mm and FWHM y =36 mm), bGEM thermal neutron counting efficiency (≈1%), detector stability (3.45%) and the time-of-flight spectrum of the beam were successfully measured. This prototype represents the first step towards the development of thermal neutrons detectors with efficiency larger than 50% as alternatives to 3 He-based gaseous detectors

  17. Materials performance experience at spallation neutron sources

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, W.F. [Los Alamos National Laboratory, NM (United States)

    1995-10-01

    There is a growing, but not yet substantial, data base for materials performance at spallation neutron sources. Specially designed experiments using medium energy protons (650 MeV) have been conducted at the Proton Irradiation Experiment (PIREX) facility at the Swiss Nuclear Institute accelerator (SIN). Specially designed experiments using 760-800 MeV copper target have been completed at the Los Alamos Spallation Radiation Effects Facility (LASREF) at Los Alamos Meson Physics Facility (LAMPF). An extensive material testing program was initiated at LASREF in support of the German spallation neutron source (SNQ) project, before it terminated in 1985.

  18. Equilibrium and pre-equilibrium emissions in proton-induced ...

    Indian Academy of Sciences (India)

    necessary for the domain of fission-reactor technology for the calculation of nuclear transmutation ... tions occur in three stages: INC, pre-equilibrium and equilibrium (or compound. 344. Pramana ... In the evaporation phase of the reaction, the.

  19. Proton-induced $\\alpha$-cluster knockout from $^{12}$C

    CERN Document Server

    Cowley, A A; Förtsch, S V; Buthelezi, E Z; Neveling, R; Smit, F D; Steyn, G F; van Zyl, J J

    2010-01-01

    Results of a study of the (p, p ) reaction on 12C with polarized incident protons of 100 MeV are reviewed. Experimental cross section and analyzing power distributions are compared with predictions of a distorted wave impulse approximation (DWIA) theory. The theory reproduces the data reasonably well, suggesting that a quasifree knockout mechanism dominates the reaction. Spectroscopic information extracted from the cross section data is in agreement with a shell model prediction.

  20. Measurements of gas and volatile element production rates from an irradiated molten lead and lead-bismuth spallation target with proton beams of 1 and 1.4 GeV; Mesures de taux de production d'elements gazeux et volatiles lors de reactions induites par des protons de 1 et 1,4 GeV sur des cibles epaisses de plomb et plomb-bismuth liquides

    Energy Technology Data Exchange (ETDEWEB)

    Tall, Y

    2008-03-15

    The integrated project EUROTRANS (European Research Programme for the Transmutation of High Level Nuclear Waste in an Accelerator Driven System) of the 6. EURATOM Framework Programme aims to demonstrate the transmutation of radioactive waste in ADS (Accelerator Driven Sub-critical system). It will carry out a first advanced design of an experimental facility to demonstrate the technical feasibility of transmutation, and will produce a conceptual design of an industrial facility dedicated to transmutation. An ADS consists of three fundamental elements: the accelerator of protons, the sub-critical core and the spallation target. SUBATECH (physique Sub-Atomique et des Technologies associees) laboratory is involved to the study of the chosen liquid lead-bismuth as a spallation ADS target. The irradiation of liquid lead-bismuth target with energetic proton beam generates in addition to neutrons, volatile and radioactive residues. In order to determine experimentally the production rates of gas and volatile elements following a spallation reaction in a lead-bismuth target, the experiment IS419 was performed at the ISOLDE facility at CERN (Centre Europeen de la Recherche Nucleaire). This experiment constitutes the frame of the thesis whose main objective is to assess and study the production and release rates of many gas and volatile element from the irradiated lead-bismuth target with an energetic proton beam. The obtained data are compared to Monte Carlo simulation code (MCNPX) results in order to test the intranuclear cascade model of Bertini and of Cugnon, and the evaporation options of Dresner and Schmidt. (author)

  1. Measurements of proton induced gamma-ray emission cross sections and yields on Al and Na

    International Nuclear Information System (INIS)

    Chiari, M.

    2014-01-01

    Full text: The measurement of the proton induced gamma-ray emission cross sections on low-Z nuclei such as Na and Al of specific interest for environmental and cultural heritage applications, were carried out for proton beam energy from 2.5 to 4.1 MeV, including the measurement of the angular distributions of the emitted rays at selected angles, i.e. 90°, 45° and 0°, using an array of three HPGe detectors coupled to the multi-purpose scattering chamber on the +30° beamline of the Tandetron accelerator at INFN LABEC. The studied gamma-ray inducing reactions were: "2"7Al(p,p’γ)"2"7Al (gamma-ray energies 844 and 1014 keV), and "2"3Na(p,p"’γ)"2"3Na (gamma-ray energies 441 and 1636 keV) and "2"3Na(p,"αγ)"2"0Ne (gamma-ray energy 1634 keV). As a first step, the absolute efficiency of the HPGe detectors placed at 90° and 0° was improved by a factor up to 2 by designing a new target holder, with less absorbing material facing the HPGe detector at 90°, and installing a new Faraday cup/beam stopper with graphite body instead of stainless steel and a thinner Ta cap at the bottom, to reduce the shielding effect for the HPGe detector at 0°. The measurement of the absolute efficiency of the HPGe detectors of the array was carried out using a "1"5"2Eu calibration source mounted on the target holder and placed in the exact position of the target under irradiation. The proton beam energy was calibrated using an aluminum thick target and the resonances at 991.86 keV and 1683.57 keV, respectively in the (p,γ) and (p,p"’γ) reactions on "2"7Al, and a native aluminium oxide thin target and the resonance at 3470 keV in elastic scattering on "1"6O. The targets employed were thin Al (29 μg/cm"2) and NaF (35 μg/cm"2) films evaporated on thin self-supporting Ag foils; in order to obtain the differential gamma-ray inducing cross-sections, we normalized the results by the Rutherford elastic backscattering of protons from Ag, adopting a procedure not relying on the

  2. THE SPALLATION NEUTRON SOURCE PROJECT - PHYSICAL CHALLENGES.

    Energy Technology Data Exchange (ETDEWEB)

    WEI,J.

    2002-06-03

    The Spallation Neutron Source (SNS) is designed to reach an average proton beam power of 1.4 MW for pulsed neutron production. This paper summarizes design aspects and physical challenges to the project.

  3. The spallation neutron source: New opportunities

    Indian Academy of Sciences (India)

    The spallation neutron source (SNS) facility became operational in the spring of ... the opportunity to develop science and instrumentation programs which take ... in telecommunications, manufacturing, transportation, information technology, ...

  4. The spallation in reverse kinematics: what for a coincidence measurement?; La spallation en cinematique inverse: pourquoi faire une mesure en coincidence?

    Energy Technology Data Exchange (ETDEWEB)

    Ducret, J.E

    2006-07-15

    The Spaladin installation has been designed to study spallation reactions in reverse kinematics. Furthermore, the heavy and light fragments are detected by coincidence which allows us to get an instantaneous picture of the reaction at a level of accuracy better than that obtained through inclusive measurement. The first part is dedicated to the theoretical description of the different mechanisms involved in the spallation reactions. In the second part we describe the Spaladin installation and report some results on the reaction: Fe{sup 56} + p at an energy of 1 GeV/nucleon. In the third part we expose the performance of the installation through its simulation with the Geant-IV model. We present a study about the sensitivity of the Spaladin installation to theoretical predictions. The fourth part is dedicated to the future experiments that will be performed with the Spaladin installation. (A.C.)

  5. Targets for neutron beam spallation sources

    International Nuclear Information System (INIS)

    Bauer, G.S.

    1980-01-01

    The meeting on Targets for Neutron Beam Spallation Sources held at the Institut fuer Festkoerperforschung at KFA Juelich on June 11 and 12, 1979 was planned as an informal get-together for scientists involved in the planning, design and future use of spallation neutron sources in Europe. These proceedings contain the papers contributed to this meeting. For further information see hints under relevant topics. (orig./FKS)

  6. Excitation functions of pion reactions on 14N, 16O, and 19F through the (3,3) resonance

    International Nuclear Information System (INIS)

    Jacob, N.P. Jr.; Markowitz, S.S.

    1976-01-01

    Cross sections for pion-induced reactions of the form (π,πN) and more complex spallation reactions of the form (π,X) have been measured from 50--550 MeV on the target nuclei 14 N, 16 O, and 19 F using the secondary pion beams at the Lawrence Berkeley Laboratory 184-inch synchrocyclotron and the Clinton P. Anderson Meson Physics Facility. The dominance of the (3,3) free-particle resonance is seen in all excitation functions determined in this work. Relative to the 12 C(π/sup plus-or-minus/,πN) 11 C reactions, the (π/sup plus-or-minus/,πN) reactions on 14 N, 16 O, and 19 F have magnitudes of 0.2, 1, and 0.7, respectively. The cross section ratio R=sigma (π - ,π - n)/sigma (π + ,π N) =1.68+-0.18 for 14 N at 188+-15 MeV, 1.68+-0.05 for 16 O at 188+-9 MeV, and 1.68+-0.03 for 19 F at 178+-2 MeV incident pion energy. The results from this work are compared to previous pion work, analogous proton-induced reactions, Monte Carlo intranuclear cascade-evaporation calculations, and to a semiclassical nucleon charge-exchange model which convincingly explains the (π,πN) reaction mechanism in the (3,3) resonance region

  7. The application of proton induced X-ray emission in criminalistics

    International Nuclear Information System (INIS)

    Li Zhenyuan; Xie Shuxian

    1993-01-01

    The determination method of trace elements in high pure gold by proton induced X-ray emission is reported. The target preparation, design of physical experiment, data proceeding and the analysis of gold samples by the internal standard of single-standard are discussed. Using this determination method, the identification of a sample of high pure gold is performed

  8. Proton induced X-ray emission analysis of trace elements in human blood serum

    International Nuclear Information System (INIS)

    Cheek, D.B.; Hay, H.J.; Newton, C.S.

    1979-01-01

    Proton induced x-ray emission has been used for quantitative analyses of trace elements in blood serum samples. This work is part of a survey concerned with Zn, Cu, Fe, Cr, Mn and Se in Australian Aboriginal people not receiving optimal diet. Special attention is being directed to Cr because of the high incidence of diabetes mellitus in these people

  9. Proton-induced X-ray emission analysis of Jordanian cigarettes

    International Nuclear Information System (INIS)

    Hallak, A.B.

    1981-01-01

    Proton-induced X-ray emission spectroscopy was applied to determine the concentration of 11 elements in cigaretta tobacco of four brands commercially made in Jordan, and one foreign brand. The results are expressed in absolute amount per cigarette. Cigarette wrapping paper and cigarette smoke were also anlayzed. The significance of some of the elements found in the samples are discussed. (author)

  10. Contribution to the element analysis method by proton-induced X-ray spectroscopy

    International Nuclear Information System (INIS)

    Montenegro, E.C.

    1977-02-01

    A critical analysis of the process for the mass determination using proton induced X-ray is presented. Problems such as univocity, reproducibility, precision, accuracy and sensibility, as well as possible effects of absorption in the sample are considered. (author) [pt

  11. Technical design report of spallation neutron source facility in J-PARC

    International Nuclear Information System (INIS)

    Sakamoto, Shinichi

    2012-02-01

    One of the experimental facilities in Japan Proton Accelerator Research Complex (J-PARC) is the Materials and Life Science Experimental Facility (MLF), where high-intensity neutron beams are used as powerful probes for basic research on materials and life science, as well as research and development in industrial engineering. Neutrons are generated with nuclear spallation reaction by bombarding a mercury target with high-intensity proton beams. The neutrons are slowed down with supercritical hydrogen moderators and then extracted as beams to each experimental apparatus. The principal design of the spallation neutron source is compiled in this comprehensive report. (author)

  12. Spallation target-moderator-reflector studies at the Weapons Neutron Research facility

    International Nuclear Information System (INIS)

    Russell, G.J.; Gilmore, J.S.; Prael, S.D.; Robinson, H.; Howe, S.D.

    1980-01-01

    Basic neutronics data, initiated by 800-MeV proton spallation reactions, are important to spallation neutron source development and electronuclear fuel production. Angle-dependent and energy-dependent neutron production cross sections, energy-dependent and total neutron yields, thermal and epithermal neutron surface and beam fluxes, and fertile-to-fissile conversion ratios are being measured. The measurements are being done at the Weapons Neutron Research facility on a variety of targets and target-moderator-reflector configurations. The experiments are relevant to the above applications, and provide data to validate computer codes. Preliminary results are presented and compared to calculated predictions. 13 figures

  13. Fission dynamics in the proton induced fission of heavy nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Rubchenya, V.A. E-mail: rubchen@phys.jyu.fi; Trzaska, W.H.; Itkis, I.M.; Itkis, M.G.; Kliman, J.; Kniajeva, G.N.; Kondratiev, N.A.; Kozulin, E.M.; Krupa, L.; Pokrovski, I.V.; Voskressenski, V.M.; Hanappe, F.; Materna, T.; Dorvaux, O.; Stuttge, L.; Chubarian, G.; Khlebnikov, S.V.; Vakhtin, D.N.; Lyapin, V.G

    2004-04-05

    Multi-parameter correlation study of the reaction {sup 242}Pu(p, f) at E{sub p} 13, 20 and 55 MeV has been carried out. Fission fragment mass and kinetic energy distributions and the double differential neutron spectra have been measured. It was observed that the two-humped shape of mass distributions prevailed up to highest proton energy. Manifestation of the nuclear shell Z 28 near fragment mass A{sub fr} = 70 has been detected. The experimental results were analyzed in the framework of a time-dependent statistical model with inclusion of nuclear friction effects in the fission process. The multi-parameter correlation study of the reaction.

  14. Spallation symbiont and thorium breeding

    International Nuclear Information System (INIS)

    Furukawa, Kazuo

    1991-01-01

    The medium term world energy and environment countermeasures for 2020-2070 are not yet clearly established. The forecast of energy situation hereafter, its problems and the measures for solution are considered. World trend is removing borders, and the north-south problems are increasing the importance. The rational and clear idea with the support of concrete technology is required. The demand of energy will increase enormously at the annual rate of 2.3%. The world energy situation was forecast considering the increase of population, and it will be 115 TW at the end of the next century. The present status, problems and the countermeasures in nuclear fission energy technology are explained. The countermeasures should be based on three principles, namely Th-U-233 cycle, the utilization of molten fluoride fuel medium and the separation of molten salt breeders and molten salt reactors. Accelerator molten salt breeders, small molten salt reactors, the nuclear fuel cycle and the annihilation process for radioactive wastes are reported. The perspective that the nuclear energy system, in which the reactor safety, the measures to wastes and others are improved by the spallation-fission symbiont using thorium molten salt as the working medium, can be constructed is shown. (K.I.)

  15. Target for a spallation source

    International Nuclear Information System (INIS)

    Fassbender, J.; Meister, G.

    1983-01-01

    This invention concerns a liquid metal target for a spallation source. It is composed of a flow channel in which liquid metal flows at a sufficiently high rate. The flow channel has an aperture to let in the proton beam; it is shaped in a way as to generate by appropriately diverting the liquid flow inertial forces which are designed so that they avoid liquid metal penetrating through the aperture. This is achieved by the fact that the combined effect of inertial forces and gravitational forces causes near the aperture the formation of a liquid surface of the channel sides that is more or less parallel to the channel side having the aperture. According to the invention this effect can be obtained by using a bent channel piece with the aperture placed in the side pointing towards the centre of curvature or by constricting the flow of liquid before it gets to the aperture and subsequent expansion behind it. A combination of the two methods is possible according to the invention. (orig./PW)

  16. Target for a spallation source

    International Nuclear Information System (INIS)

    Fassbender, J.; Meister, G.

    1981-01-01

    This invention concerns a liquid metal target for a spallation source. It is composed of a flow channel in which liquid metal flows at a sufficiently high rate. The flow channel has an aperture to let in the proton beam; it is shaped in a way as to generate by appropriately diverting the liquid flow inertial forces which are designed so that they avoid liquid metal penetrating through the aperture. This is achieved by the fact that the combined effect of inertial forces and gravitational forces causes near the aperture the formation of a liquid surface of the channel sides that is more or less parallel the channel side having the aperture. According to the invention this effect can be obtained by using a bent channel piece with the aperture placed in the side pointing towards the centre of curvature or by constricting the flow of liquid before it gets to the aperture and subsequent expansion behind it. A combination of the two methods is possible according to the invention. (orig.) [de

  17. Synchrotron-driven spallation sources

    CERN Document Server

    Bryant, P J

    1996-01-01

    The use of synchrotrons for pulsed neutron spallation sources is an example of scientific and technological spin-off from the accelerator development for particle physics. Accelerator-driven sources provide an alternative to the continuous-flux, nuclear reactors that currently furnish the majority of neutrons for research and development. Although the present demand for neutrons can be adequately met by the existing reactors, this situation is unlikely to continue due to the increasing severity of safety regulations and the declared policies of many countries to close down their reactors within the next decade or so. Since the demand for neutrons as a research tool is, in any case,expected to grow, there has been a corresponding interest in sources that are synchrotron-driven or linac-driven with a pulse compression ring and currently several design studies are being made. These accelerator-driven sources also have the advantage of a time structure with a high peak neutron flux. The basic requirement is for a...

  18. Neutron PSDs for the next generation of spallation neutron sources

    CERN Document Server

    Eijk, C W

    2002-01-01

    A review of R and D for neutron PSDs to be used at anticipated new spallation neutron sources: the Time-of-Flight system facility, European Spallation Source, Spallation Neutron Source and Neutron Arena, is presented. The gas-filled detectors, scintillation detectors and hybrid systems are emphasized.

  19. New science at the European Spallation Source

    Energy Technology Data Exchange (ETDEWEB)

    Finney, J L [University Coll., London (United Kingdom). Dept. of Physics and Astronomy

    1996-05-01

    The European Spallation Source is a trans-European project aimed at the ultimate construction of a next-generation pulsed spallation neutron source that will deliver 30 times the beam power of ISIS. The reference design for the proposed source has been set, and work is in progress to develop an updated scientific case for the construction of the source early in the next century. Together with improvements in instrumentation, effective flux gains of over two orders of magnitude are likely in some areas, opening up major new opportunities for the exploitation of neutron studies in fundamental, strategic, and applied science. (author)

  20. Protonation-induced ultrafast torsional dynamics in 9-anthrylbenzimidazole: a pH activated molecular rotor.

    Science.gov (United States)

    Nandi, Amitabha; Kushwaha, Archana; Das, Dipanwita; Ghosh, Rajib

    2018-03-07

    We report the photophysical properties and excited state dynamics of 9-anthrylbenzimidazole (ANBI) which exhibits protonation-induced molecular rotor properties. In contrast to the highly emissive behavior of neutral ANBI, protonation of the benzimidazole group of ANBI induces efficient nonradiative deactivation by ultrafast torsional motion around the bond connecting the anthracene and benzimidazole units, as revealed by ultrafast transient absorption and fluorescence spectroscopy. Contrary to viscosity-independent fluorescence of neutral dyes, protonated ANBI is shown to display linear variation of emission yield and lifetime with solvent viscosity. The protonation-induced molecular rotor properties in the studied system are shown to be driven by enhanced charge transfer and are corroborated by quantum chemical calculations. Potential application as a microviscosity sensor of acidic regions in a heterogeneous environment by these proton-activated molecular rotor properties of ANBI is discussed.

  1. Elemental analysis of coal by proton-induced x-ray emission analysis

    International Nuclear Information System (INIS)

    Cronch, S.M.; Ehmann, W.D.; Laumer, H.W.; Gabbard, F.

    1976-01-01

    Proton-induced x-ray emission was used to determine elemental concentrations in solid coal samples. The coal samples were irradiated with 2.5 to 5.5 MeV protons. Concentrations were determined from characteristic x-ray yields taking into account matrix absorption. The precision is shown by replicate analysis and the accuracy by comparison with results obtained by other laboratories using different techniques

  2. Efficiency of an LBE spallation target in an accelerator-driven molten salt subcritical reactor

    Energy Technology Data Exchange (ETDEWEB)

    Bak, Sang-In [Sungkyunkwan University, Suwon (Korea, Republic of); Hong, Seung-Woo [Sungkyunkwan University, Suwon (Korea, Republic of); Kadi, Yacine [CERN, Geneva (Switzerland)

    2016-10-15

    An Accelerator-Driven System (ADS) combined with a subcritical Molten Salt Reactor (MSR) is a type of hybrid reactor originally designed to breed uranium from thorium or to incinerate long-lived minor actinides in nuclear wastes. In an MSR, the salt material is used not only as a nuclear fuel but also as a primary coolant. In addition, this material is used as a target for inducing spallation neutrons in most AD-MSR concepts. A high energy proton beam impinges on a heavy metal target to induce spallation reactions and produces neutrons. Accordingly, a reliable proton accelerator is needed to feed the source neutrons. As ADSs have been criticized for requiring high power accelerators, minimization of beam power is an important aspect of ADS design. A primary concern associated with ADS development is stable high-power accelerators. We therefore studied the neutron source efficiencies of an AD-MSR involving chloride fuels by including a Pb-Bi eutectic (LBE) spallation target. The proton source efficiency and the accelerator beam power required have been studied for an AD-MSR. Adoption of an LBE spallation target induces an increase in proton source efficiencies in comparison to the case without a spallation target. Thus the presence of an efficient spallation target is useful in the reduction of the beam power of an accelerator. Almost 33 % of the beam power can be reduced in comparison to the case without the target for NaCl-Th/{sup 233}U fuel, and about 16 % for NaCl-U/TRU fuel. The beam power amplifications increase by 1.5 times for NaCl-Th/{sup 233}U and 1.2 times for NaCl-U/TRU in comparison with the no target AD-MSR.

  3. Sideward peak of intermediate mass fragments in high energy proton induced reactions

    International Nuclear Information System (INIS)

    Ohnishi, A.; Hirata, Y.; Otuka, N.; Nara, Y.; Kido, T.; Maruyama, T.; Takada, H.; Chiba, S.

    2002-01-01

    We study the sideward enhanced IMF emission mechanism by using a combined framework of a transport model (JAM/MF) and a newly developed Non-Equilibrium Percolation (NEP) model. We find that the sideward enhancement may emerge if the fragmentation takes place within a short time scale around 20 fm/c. Within this short time period, the un-heated part of the residual nucleus is kept to have doughnut shape, then the Coulomb repulsion from this shape strengthens the sideward emission of IMFs. (author)

  4. Investigating the fission process at high excitation energies through proton induced reactions on 181Ta

    International Nuclear Information System (INIS)

    Ayyad, Y.; Benlliure, J.; Casajeros, E.; Alvarez Pol, H.; Paradela, C.; Perez-Loureido, D.; Tarrio, D.; Bacquias, A.; Boudard, A.; Kezzar, K.; Leray, S.; Enqvist, T.; Foehr, V.; Kelic, A.; Pleskac, R.

    2010-01-01

    In this work we have investigated the total fission cross section of 181 Ta + 1 H at FRS (Fragment Separator - GSI) at 1, 0.8, 0.5 and 0.3 GeV with a specific setup, providing high accuracy measurements of the cross section values. the comparison of our data with previous results reveals a good agreement at high energies. However the situation remains unclear at lower energies. In general, our results covering a wide range of energy, are smoother. We have also compared the results obtained in this experiment, with several calculations performed with the intra-nuclear cascade model (INCL v4.1) coupled to de-excitation code (ABLAv3p), according to two different models describing fission process at high-excitation energies: statistical model of Bohr and Wheeler and the dynamical description of the fission process. We have showed that a simple statistical description largely over-predict the measured cross-section. Only a dynamical description of the fission, involving the role of the viscosity of the nuclear matter, provides a realistic result.

  5. Study of proton-induced reactions and correlation with fast-neutron scattering

    International Nuclear Information System (INIS)

    Hansen, L.F.

    1982-01-01

    The generation of cross sections for fast neutron-nucleon interactions obtained from elastic and charge-exchange proton data is discussed in terms of the Lane model formalism. A general description of the interaction of nucleons with nuclei is presented in terms of the optical model and the extended (or coupled-channel) optical model, together with the relation of these models to microscopic calculations of the nucleon-nucleon interaction. Comparisons between neutron elastic data and calculations carried out with optical model potentials obtained from (p,p) and (p,n) data are presented for a large number of nuclei. The validity of the Lane model and the importance of coupled effects in the actinide region are shown in a detailed comparison of calculations for elastic and inelastic neutron differential cross sections and measurements for 232 Th and 238 U

  6. Application of proton-induced X-ray emission method to determination of lead content in blood

    International Nuclear Information System (INIS)

    Slominska, D.; Jarczyk, L.; Rokita, E.; Strzalkowski, A.; Losiowski, A.; Macheta, A.; Sych, M.; Moszkowicz, S.

    1979-01-01

    The proton induced X-ray emission method is applied for determination of lead content in the blood of the people exposed to contact with ethyline vapours and people working in lead-zinc works. (author)

  7. The Spallation Neutron Source RF Reference System

    CERN Document Server

    Piller, Maurice; Crofford, Mark; Doolittle, Lawrence; Ma, Hengjie

    2005-01-01

    The Spallation Neutron Source (SNS) RF Reference System includes the master oscillator (MO), local oscillator(LO) distribution, and Reference RF distribution systems. Coherent low noise Reference RF signals provide the ability to control the phase relationships between the fields in the front-end and linear accelerator (linac) RF cavity structures. The SNS RF Reference System requirements, implementation details, and performance are discussed.

  8. SUPERCONDUCTING LINAC FOR THE SPALLATION NEUTRON SOURCE

    International Nuclear Information System (INIS)

    STOVALL, J.; NATH, S.

    2000-01-01

    The Spallation Neutron Source (SNS) linac is comprised of both normal and superconducting rf (SRF) accelerating structures. The SRF linac accelerates the beam from 186 to 1250 MeV through 117 elliptical, multi-cell niobium cavities. This paper describes the SRF linac architecture, physics design considerations, cavity commissioning, and the expected beam dynamics performance

  9. Neutron Production by Muon Spallation I: Theory

    International Nuclear Information System (INIS)

    Luu, T; Hagmann, C

    2006-01-01

    We describe the physics and codes developed in the Muon Physics Package. This package is a self-contained Fortran90 module that is intended to be used with the Monte Carlo package MCNPX. We calculate simulated energy spectra, multiplicities, and angular distributions of direct neutrons and pions from muon spallation

  10. Linac design for the European spallation source

    Energy Technology Data Exchange (ETDEWEB)

    Klein, H. [Universitaet Postfach, Frankfurt am Main (Germany)

    1995-10-01

    A study group has started to develop a conceptual design for a European Spallation Source (ESS). This pulsed 5 MW source presently consists of a 1.334 GeV linac and two compressor rings. In the following mainly the high intensity linac part will be discussed, which has some features of interest for accelerators for transmutation of radioactive waste too.

  11. Design of the MYRRHA Spallation Target Assembly

    International Nuclear Information System (INIS)

    Keijers, S.; Fernandez, R.; Stankovskiy, A.; Kennedy, G.; Van Tichelen, K.

    2015-01-01

    MYRRHA (Multi-purpose hybrid Research Reactor for High-tech Applications) is a multi-purpose research facility currently being developed at SCK.CEN. MYRRHA is based on the ADS (Accelerator Driven System) concept where a proton accelerator, a spallation target and a subcritical reactor are coupled. MYRRHA will demonstrate the ADS full concept by coupling these three components at a reasonable power level. As a flexible irradiation facility, the MYRRHA research reactor will be able to work in both critical and subcritical modes. In this way, MYRRHA will allow fuel developments for innovative reactor systems, material research for GEN IV and fusion reactors, and radioisotope production for medical and industrial applications. MYRRHA will be cooled by Lead Bismuth Eutectic (LBE) and will play an important role in the development of the Pb-alloys technology needed for the LFR (Lead Fast Reactor) GEN IV concept. This paper describes the evolution of the MYRRHA spallation target design. In the early phase of the MYRRHA project (XT-ADS), the target design was based on a dedicated spallation loop inside the primary reactor vessel. Within the core, the 3 central fuel assembly positions were occupied by the spallation target, which enabled a windowless design created by a free surface of LBE facing the proton beam. The windowless option was preferred because of high heat loads in combination with severe irradiation damage in the target region would result in unacceptably short lifetimes of a target window. The LBE in the loop served as spallation target and as target coolant, but was separated from the LBE cooling the reactor core. The loop was equipped with its own pump, heat exchanger and conditioning system. The change from cyclotron to linear accelerator allowed the increase in proton energy from 350 MeV to 600 MeV. This modification led to an important reduction of the specific heat load at the target level and an improvement of the neutronic performance. In addition to

  12. Simultaneous determination of 14N and 15N isotopes in opium by proton induced γ-ray emission technique

    International Nuclear Information System (INIS)

    Pritty Rao; Reddy, G.L.N.; Vikram Kumar, S.; Ramana, J.V.; Raju, V.S.; Sanjiv Kumar

    2012-01-01

    The paper describes the simultaneous determination of 14 N and 15 N isotopes in opium by proton induced γ-ray emission (PIGE) technique. The isotopic ratio of 14 N and 15 N is a useful parameter for assigning provenance of (seized) illicit drugs. The measurement, non-destructive in nature, is performed on pellets made up of opium powders and is based on the prompt detection of 2.313 and 4.4 MeV γ-rays emanating from 14 N(p,p'γ) 14 N and 15 N(p,αγ) 12 C nuclear reactions respectively, induced simultaneously by 3.6-3.8 MeV proton beam. Positive as well as negative deviations from the natural isotopic abundance (99.63:0.37) were observed in the samples. The precision of the measurements is about 4%. The methodology provides an easy and rapid approach to determine the isotopic ratio of 14 N and 15 N and has been used for the first time in the analysis of opium. (author)

  13. Spallation neutron experiment at SATURNE

    Energy Technology Data Exchange (ETDEWEB)

    Meigo, Shin-ichiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-11-01

    The double differential cross sections for (p,xn) reactions and the spectra of neutrons produced from the thick target have been measured at SATURNE in SACLAY from 1994 to 1997. The status of the experiment and the preliminary experimental results are presented. (author)

  14. A study of non-elastic reaction rates for the ADS materials in the environment of spallation neutrons produced by 1.6 GeV d-beam

    Czech Academy of Sciences Publication Activity Database

    Bhatia, C.; Adam, Jindřich; Kumar, V.; Katovsky, K.; Majerle, Mitja; Solnyshkin, A. A.; Tsoupko-Sitnikov, V. M.

    2012-01-01

    Roč. 70, č. 7 (2012), s. 1254-1260 ISSN 0969-8043 R&D Projects: GA MŠk LA08002 Institutional support: RVO:61389005 Keywords : accelerator driven sub-critical system (ADS) nuclear data * (n, xnyp) reactions * spectrum average cross-section Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.179, year: 2012

  15. Spallation RI beam facility and heavy element nuclear chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Nagame, Yuichiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-11-01

    An outline of the spallation RI (Radioactive Ion) beam facility is presented. Neutron-rich nuclides are produced in the reaction of high intensity (10-1000 {mu}A) protons with energy of 1.5 GeV and an uranium carbide target. Produced nuclides are ionized in an isotope separator on-line (ISOL) and accelerated by the JAERI tandem and the booster linac. Current progress and a future project on the development of the RI beam facility are given. Studies of transactinide elements, including the synthesis of superheavy elements, nuclear structure far from stability, and RI-probed material science are planned with RI beams. An outlook of the transactinide nuclear chemistry studies using neutron-rich RI beams is described. (author)

  16. Trace metal content in aspirin and women's cosmetics via proton induced x-ray emission (PIXE)

    International Nuclear Information System (INIS)

    Hichwa, B.P.; Pun, D.D.; Wang, D.

    1981-01-01

    A multielemental analysis to determine the trace metal content of generic and name-brand aspirins and name-brand lipsticks was done via proton induced x-ray (PIXE) measurements. The Hope College PIXE system is described as well as the target preparation methods. The trace metal content of twelve brands of aspirin and aspirin substitutes and fourteen brands of lipstick are reported. Detection limits for most elements are in the range of 100 parts per billion (ppb) to 10 parts per million

  17. Trace element analysis in liquids by proton induced x-ray emission

    International Nuclear Information System (INIS)

    Deconninck, G.

    Proton induced x-ray emission (PIXE) from liquid has been developed for quantitative and simultaneous analysis of trace elements. Liquid drops and trickles are bombarded at atmospheric pressure, x-rays are detected in a non dispersive Si(Li) solid state detector. Absolute determinations are made by comparison with standard solutions. Detection limits in a 5 minutes run are in the ppm range for a single drop (0.05 ml). The application of this technique to the determination of trace elements in biological liquids is investigated (Cr, Mn, Fe, Co, Ni, Cu, Zn, in plant extracts, haemocyanine, albumins...). (author)

  18. Proton induced X-ray emission (PIXE) analysis at Lucas Heights

    International Nuclear Information System (INIS)

    Cohen, D.; Duerden, P.

    1979-02-01

    The state of the proton induced X-ray emission (PIXE) work at Lucas Heights is reported together with a full description of the experimental arrangement and its use for analysis of trace elements (Z >or= 14). The fundamentals of PIXE are examined in detail with a view to understanding not only the background continuum but also the X-ray production mechanisms. Quantitative predictions for the number of X-rays detected after proton bombardment of the target have been made and these compare well with experiments

  19. Proton-induced production cross-sections and production rates of 41Ca from Ni

    International Nuclear Information System (INIS)

    Schnabel, C.; Synal, H.-A.; Gartenmann, P.; Santos-Arevalo, F.J.; Gomez-Martinez, I.; Suter, M.; Tarabischi, A.; Bastian, T.; Sudbrock, F.; Herpers, U.; Leya, I.; Gloris, M.; Michel, R.

    2004-01-01

    Proton-induced production cross-sections of 41 Ca from Ni are presented. Moreover, depth-dependent production rates of 41 Ca from Ni were determined in a meteoroid simulation experiment. Based on these data, modelled production rates of 41 Ca from Ni in iron meteoroids are presented as a function of depth and size. These data are relevant for modelling the production rate ratio of 41 Ca/ 36 Cl in metal phases of meteoroids and thus for the application of the 41 Ca- 36 Cl method to determine terrestrial ages of meteorites

  20. High energy proton-induced radioactivity in HgI2 crystals

    International Nuclear Information System (INIS)

    Porras, E.; Ferrero, J.L.; Sanchez, F.; Ruiz, J.A.; Lei, F.

    1995-01-01

    Mercuric iodide (HgI 2 ) semiconductor crystals are generating a lot of interest as room temperature solid state detectors for hard X-ray astronomy observations. For these applications one of the most important background sources is the cosmic proton induced radioactivity in the detector material. In order to study this background noise contribution a 1x1x1 cm HgI 2 crystal was irradiated with high energy protons. The resulting long-lived unstable isotopes and their production rates have been identified and compared with Monte Carlo simulations. ((orig.))

  1. A linac for the Spallation Neutron Source

    International Nuclear Information System (INIS)

    Jason, A.J.

    1998-01-01

    The Spallation Neutron Source Project (SNS), to be constructed at Oak Ridge National Laboratory, accelerates H - ions to an energy of 1.0 GeV with an average current of 1-mA for injection into an accumulator ring that produces the short intense burst of protons needed for the spallation-neutron source. The linac will be the most intense source of H - ions and as such requires advanced design techniques to meet project technical goals. In particular, low beam loss is stressed for the chopped beam placing strong requirements on the beam dynamics and linac construction. Additionally, the linac is to be upgraded to the 2- and 4-MW beam-power levels with no increase in duty factor. The author gives an overview of the linac design parameters and design choices made

  2. Neutron moderators for the European Spallation Source

    DEFF Research Database (Denmark)

    Klinkby, Esben Bryndt; Zanini, L.; Batkov, K.

    The design of the neutron moderators for the European Spallation Source, intended to be installed at the start of operations of the facility in 2019 has now been finalized and the moderators are being fabricated. Among the driving principles in the design have been flexibility for instruments...... to have access to cold and thermal neutrons with highest possible source brightness. Different design and configuration options were evaluated. The final configuration accepted for construction foresees two moderators with identical para-hydrogen (so-called "butterfly") shape, but different heights......, placed above and below the spallation target. Both moderators are able to serve the full 2 x 120° beam extraction sectors of instrument suite. The top, 3-cm tall moderator, has both high thermal and high cold brightness, more than by a factor of 2.5 compared to the previous design of the Technical Design...

  3. New neutron physics using spallation sources

    International Nuclear Information System (INIS)

    Bowman, C.D.

    1988-01-01

    The extraordinary neutron intensities available from the new spallation pulsed neutron sources open up exciting opportunities for basic and applied research in neutron nuclear physics. The energy range of neutron research which is being explored with these sources extends from thermal energies to almost 800 MeV. The emphasis here is on prospective experiments below 100 keV neutron energy using the intense neutron bursts produced by the Proton Storage Ring (PSR) at Los Alamos. 30 refs., 10 figs

  4. Decommissioning Plan for European Spallation Source

    Directory of Open Access Journals (Sweden)

    Ene Daniela

    2017-01-01

    Full Text Available This paper is a survey of the European Spallation Source initial decommissioning plan developed in compliance with Swedish Regulatory Authority requirements. The report outlines the decommissioning strategy selected and the baseline plan for decommissioning. Types and quantities of radioactive waste estimated to be generated at the final shut-down of the facility are further provided. The paper ends up with the analysis of the key elements of the decommissioning plan and the recommendations to the ESS management team..

  5. Synthesis of neutron-rich transuranic nuclei in fissile spallation targets

    OpenAIRE

    Mishustin, Igor; Malyshkin, Yury; Pshenichnov, Igor; Greiner, Walter

    2014-01-01

    A possibility of synthesizing neutron-reach super-heavy elements in spallation targets of Accelerator Driven Systems (ADS) is considered. A dedicated software called Nuclide Composition Dynamics (NuCoD) was developed to model the evolution of isotope composition in the targets during a long-time irradiation by intense proton and deuteron beams. Simulation results show that transuranic elements up to Bk-249 can be produced in multiple neutron capture reactions in macroscopic quantities. Howeve...

  6. Linac-driven spallation-neutron source

    International Nuclear Information System (INIS)

    Jason, A.J.

    1995-01-01

    Strong interest has arisen in accelerator-driven spallation-neutron sources that surpass existing facilities (such as ISIS at Rutherford or LANSCE at Los Alamos) by more than an order of magnitude in beam power delivered to the spallation target. The approach chosen by Los Alamos (as well as the European Spallation Source) provides the full beam energy by acceleration in a linac as opposed to primary acceleration in a synchrotron or other circular device. Two modes of neutron production are visualized for the source. A short-pulse mode produces 1 MW of beam power (at 60 pps) in pulses, of length less than 1 ms, by compression of the linac macropulse through multi-turn injection in an accumulator ring. A long-pulse mode produces a similar beam power with 1-ms-long pulses directly applied to a target. This latter mode rivals the performance of existing reactor facilities to very low neutron energies. Combination with the short-pulse mode addresses virtually all applications

  7. 2. International workshop on spallation materials technology

    International Nuclear Information System (INIS)

    Carsughi, F.; Mansur, L.K.; Sommer, W.F.; Ullmaier, H.

    1997-11-01

    This document contains 25 papers consisting an abstract prepared by the authors, followed by copies of the presentation viewgraphs used by speakers. The topics were: Target options for SINQ; Overview of the NSNS target system; ISIS target and moderator materials; Trispal project; JHF N-ARENA; Design, load conditions and manufacturing aspect of the ESS MERCURY TARGET unit; Radiation damage simulatiion to measure recoil spectra distribution; Radiation damage calculation to spallation neutron source materials; Hadron-induced neutron production in Pb and U targets from 1-5 GeV; Proton beam effects on W rods, surface cooled by water; Corrosion and fatigue behavior of metals and alloys in high radiation fields; compability of materials with mercury for NSNS target system; Research activities at PSI on structural materials for spallation neutron source; The accelerator production of tritium materials reserach program and Los Alamos National Laboratory; Experimental program on irradiation effects in structural materials of the Trispal project; First pulsed power materials test at Livermore; Plan of thermal shock fracture test at JAERI; Is there a hydrogen problem in target materials in high-power spatllation source?; Materials consideration for the NSNS target; Materials durability issures in spallation neutron source applications; Post-irradiation investigations at the FZJ; Microstructure and hardening of steels containing high helium concentrations; Tensile properties and microstructure of the F82H ferritic-martensitic steel after irradiation in the PIREX facility

  8. The Columbia University proton-induced soft x-ray microbeam.

    Science.gov (United States)

    Harken, Andrew D; Randers-Pehrson, Gerhard; Johnson, Gary W; Brenner, David J

    2011-09-15

    A soft x-ray microbeam using proton-induced x-ray emission (PIXE) of characteristic titanium (K(α) 4.5 keV) as the x-ray source has been developed at the Radiological Research Accelerator Facility (RARAF) at Columbia University. The proton beam is focused to a 120 μm × 50 μm spot on the titanium target using an electrostatic quadrupole quadruplet previously used for the charged particle microbeam studies at RARAF. The proton induced x-rays from this spot project a 50 μm round x-ray generation spot into the vertical direction. The x-rays are focused to a spot size of 5 μm in diameter using a Fresnel zone plate. The x-rays have an attenuation length of (1/e length of ~145 μm) allowing more consistent dose delivery across the depth of a single cell layer and penetration into tissue samples than previous ultra soft x-ray systems. The irradiation end station is based on our previous design to allow quick comparison to charged particle experiments and for mixed irradiation experiments.

  9. Chirality induction and protonation-induced molecular motions in helical molecular strands.

    Science.gov (United States)

    Kolomiets, Elena; Berl, Volker; Lehn, Jean-Marie

    2007-01-01

    The long oligopyridinedicarboxamide strand 9, containing 15 heterocyclic rings has been synthesized and its helical structure determined by X-ray crystallography. It was shown that the shorter analogue 6 displays induced circular dichroism and amplification of induced chirality upon dissolution in an optically active solvent, diethyl-L-tartrate. A novel class of helical foldamers was prepared, strands 14-16, based on two oligopyridine carboxamide segments linked through a L-tartaric acid derived spacer. These tartro strands display internal chirality induction as well as chirality amplification. NMR spectroscopy (on 8 and 9) and circular dichroism (on 16) studies show that the oligopyridine carboxamide strands undergo reversible unfolding/folding upon protonation. The protonation-induced unfolding has been confirmed by X-ray crystallographic determination of the molecular structure of the extended protonated heptameric form 8(+). The molecular-scale mechano-chemical motions of the protonation-induced structural switching consist of a change of the length of the molecule, from 6 angstroms (6, coiled form) to 29 angstroms (8(+), uncoiled form) for the heptamer and from 12.5 angstroms (9, coiled form, X-ray structure) to 57 angstroms (9(+), uncoiled form, from modeling) for the pentadecamer. Similar unfolding/folding motional processes take place in the L-tartro strands 15 and 16 upon protonation/deprotonation, with loss of helicity-induced circular dichroism on unfolding as shown for the protonated form 16(+).

  10. Measurement of proton induced γ-ray emission cross sections on Al from 2.5 to 4.1 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Chiari, M., E-mail: chiari@fi.infn.it [INFN-Florence and Department of Physics and Astronomy, University of Florence, Sesto Fiorentino, Florence I-50019 (Italy); Melon, B.; Salvestrini, L. [INFN-Florence and Department of Physics and Astronomy, University of Florence, Sesto Fiorentino, Florence I-50019 (Italy); Fonseca, M. [Centro de Física Nuclear da Universidade de Lisboa, 1649-003 Lisboa (Portugal); Alves, E. [IST/ITN, Campus Tecnológico e Nuclear, Universidade Técnica de Lisboa, E.N. 10, 2866-953 Sacavém (Portugal); Jesus, A.P. [Centro de Física Nuclear da Universidade de Lisboa, 1649-003 Lisboa (Portugal)

    2014-08-01

    Differential cross section for proton induced γ-ray emission from the reaction {sup 27}Al(p,p′γ){sup 27}Al (E{sub γ} = 844 and 1014 keV) were measured for proton energies from 2.5 to 4.1 MeV, at 90° and 45°, using a 29 μg/cm{sup 2} Al target evaporated on a self-supporting thin Ag film. The γ-rays were detected by two HPGe detectors with nominal 50% and 25% relative efficiency, respectively for the detector placed at 90° and at 45°. Absolute γ-ray differential cross sections were obtained with a method not dependent on the absolute values of the collected beam charge; the overall uncertainty was estimated to be better than 8%, at both angles and at all the beam energies.

  11. Fission properties of actinide nuclei from proton-induced fission at 26.5 and 62.9 MeV incident proton energies

    International Nuclear Information System (INIS)

    Demetriou, P.; Keutgen, Th.; Prieels, R.; El Masri, Y.

    2010-01-01

    Fission properties of proton-induced fission on 232 Th, 237 Np, 238 U, 239 Pu, and 241 Am targets, measured at the Louvain-la-Neuve cyclotron facility at proton energies of 26.5 and 62.9 MeV, are compared with the predictions of the state-of-the-art nuclear reaction code talys. The code couples the multimodal random neck-rupture model with the pre-equilibrium exciton and statistical models to predict fission fragment mass yields, pre- and post-scission neutron multiplicities, and total fission cross sections in a consistent approach. The sensitivity of the calculations to the input parameters of the code and possible improvements are discussed in detail.

  12. A comparison between short pulse spallation source and long pulse spallation source

    Energy Technology Data Exchange (ETDEWEB)

    Aizawa, Kazuya; Watanabe, Noboru; Suzuki, Jun-ichi; Niimura, Nobuo; Morii, Yukio; Katano, Susumu; Osakabe, Toyotaka; Teshigawara, Makoto [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Mezei, F.

    1997-11-01

    The performance for a 5 MW short pulse spallation source (SPSS) and a 4.5 MW long pulse spallation source (LPSS) in a JAERI program which is based on the availability of a 1.5 GeV superconducting linac with a 30 mA peak current for both proton and H{sup -} beams is discussed. We have examined the superiority of SPSS to LPSS. While a LPSS facility is a second option, we propose an SPSS facility as a first option. (author)

  13. A comparison between short pulse spallation source and long pulse spallation source

    International Nuclear Information System (INIS)

    Aizawa, Kazuya; Watanabe, Noboru; Suzuki, Jun-ichi; Niimura, Nobuo; Morii, Yukio; Katano, Susumu; Osakabe, Toyotaka; Teshigawara, Makoto; Mezei, F.

    1997-01-01

    The performance for a 5 MW short pulse spallation source (SPSS) and a 4.5 MW long pulse spallation source (LPSS) in a JAERI program which is based on the availability of a 1.5 GeV superconducting linac with a 30 mA peak current for both proton and H - beams is discussed. We have examined the superiority of SPSS to LPSS. While a LPSS facility is a second option, we propose an SPSS facility as a first option. (author)

  14. Lattice location of impurities in semiconductors: a RBS/channeling and proton-induced x-ray emission study

    Energy Technology Data Exchange (ETDEWEB)

    Kringhoj, P [Australian National Univ., Canberra, ACT (Australia). Research School of Physical Sciences

    1994-12-31

    Rutherford backscattering spectrometry (RBS)/channeling and proton-induced x-ray emission (PIXE) are two well established and characterised techniques. Over the last three decades RBS/channeling measurements has been performed to extract the substitutional fraction of impurities in both elemental and compound semiconductors. However, due to the limitation of RBS, only elements heavier than the host crystal can be examined (except for a few elements, where a nuclear reaction or a resonance can be used). In silicon this limitation is acceptable, due to the low mass of Si, but in the III-V compounds (e.g. InP), the technique is limited to a few elements of hardly no technological or fundamental interest. One can overcome this by combining RBS/channeling with PIXE, where PIXE is applied to detect elements with a mass lower than the host crystal. In the present work, the lattice location of Ge in InP has been studied and compared to the group-III impurity Ga, and the group-VI impurity Se which is known to be a donor. The (RBS)/channeling technique has been used to detect not only the substitutional fraction, but also the relative population of the two sublattices. The half-width is approximately equal to the characteristic angle, {psi}{sub 1}. The channeling data obtained indicate that all three dopants are located exclusively on substitutional sites and that Ga is occuping the In position, Se theP position and that Ge is distributed equally between both sublattices. 6 refs., 1 tab., 3 figs.

  15. Lattice location of impurities in semiconductors: a RBS/channeling and proton-induced x-ray emission study

    Energy Technology Data Exchange (ETDEWEB)

    Kringhoj, P. [Australian National Univ., Canberra, ACT (Australia). Research School of Physical Sciences

    1993-12-31

    Rutherford backscattering spectrometry (RBS)/channeling and proton-induced x-ray emission (PIXE) are two well established and characterised techniques. Over the last three decades RBS/channeling measurements has been performed to extract the substitutional fraction of impurities in both elemental and compound semiconductors. However, due to the limitation of RBS, only elements heavier than the host crystal can be examined (except for a few elements, where a nuclear reaction or a resonance can be used). In silicon this limitation is acceptable, due to the low mass of Si, but in the III-V compounds (e.g. InP), the technique is limited to a few elements of hardly no technological or fundamental interest. One can overcome this by combining RBS/channeling with PIXE, where PIXE is applied to detect elements with a mass lower than the host crystal. In the present work, the lattice location of Ge in InP has been studied and compared to the group-III impurity Ga, and the group-VI impurity Se which is known to be a donor. The (RBS)/channeling technique has been used to detect not only the substitutional fraction, but also the relative population of the two sublattices. The half-width is approximately equal to the characteristic angle, {psi}{sub 1}. The channeling data obtained indicate that all three dopants are located exclusively on substitutional sites and that Ga is occuping the In position, Se theP position and that Ge is distributed equally between both sublattices. 6 refs., 1 tab., 3 figs.

  16. Synthesis of neutron-rich transuranic nuclei in fissile spallation targets

    Energy Technology Data Exchange (ETDEWEB)

    Mishustin, Igor, E-mail: mishustin@fias.uni-frankfurt.de [Frankfurt Institute for Advanced Studies, J.-W. Goethe University, 60438 Frankfurt am Main (Germany); “Kurchatov Institute”, National Research Center, 123182 Moscow (Russian Federation); Malyshkin, Yury, E-mail: malyshkin@fias.uni-frankfurt.de [Frankfurt Institute for Advanced Studies, J.-W. Goethe University, 60438 Frankfurt am Main (Germany); Institute for Nuclear Research, Russian Academy of Sciences, 117312 Moscow (Russian Federation); Pshenichnov, Igor, E-mail: pshenich@fias.uni-frankfurt.de [Frankfurt Institute for Advanced Studies, J.-W. Goethe University, 60438 Frankfurt am Main (Germany); Institute for Nuclear Research, Russian Academy of Sciences, 117312 Moscow (Russian Federation); Greiner, Walter [Frankfurt Institute for Advanced Studies, J.-W. Goethe University, 60438 Frankfurt am Main (Germany)

    2015-04-15

    A possibility of synthesizing neutron-rich superheavy elements in spallation targets of Accelerator Driven Systems (ADS) is considered. A dedicated software called Nuclide Composition Dynamics (NuCoD) was developed to model the evolution of isotope composition in the targets during a long-time irradiation by intense proton and deuteron beams. Simulation results show that transuranic elements up to {sup 249}Bk can be produced in multiple neutron capture reactions in macroscopic quantities. However, the neutron flux achievable in a spallation target is still insufficient to overcome the so-called fermium gap. Further optimization of the target design, in particular, by including moderating material and covering it by a reflector could turn ADS into an alternative source of transuranic elements in addition to nuclear fission reactors.

  17. Qualification tests of materials for spallation neutron sources

    International Nuclear Information System (INIS)

    Sommer, W.F.; Maloy, S.; Wechsler, M.S.

    1997-01-01

    Several laboratories will take part in an extensive materials qualification program that includes irradiation in the proton beam and neutron field available at the Los Alamos Spallation Radiation Damage Facility (LASREF). A number of candidate materials will be exposed to prototypic spallation producing particle radiation. Studies of corrosion-related phenomena and the mitigation of these effects will also be accomplished

  18. Spallation neutron production on thick target at saturne

    International Nuclear Information System (INIS)

    David, J.C.; David, J.C.; Varignon, C.; Borne, F.; Boudard, A.; Brochard, F.; Crespin, S.; Duchazeaubeneix, J.C.; Durand, D.; Durand, J.M.; Frehaut, J.; Hannappe, F.; Lebrun, C.; Lecolley, J.F.; Ledoux, X.; Lefebvres, F.; Legrain, R.; Leray, S.; Louvel, M.; Martinez, E.; Menard, S.; Milleret, G.; Patin, Y.; Petitbon, E.; Plouin, F.; Schapira, J.P.; Stugge, L.; Terrien, Y.; Thun, J.; Volant, C.; Whittal, D.M.

    2003-01-01

    In view of the new spallation neutron source projects, we discuss the characteristics of the neutron spectra on thick targets measured at SATURNE. Some comparisons to spallation models, and especially INCL4/ABLA implemented in the LAHET code, are done. (orig.)

  19. Fundamental physics possibilities at the European Spallation Source

    DEFF Research Database (Denmark)

    Klinkby, Esben Bryndt; Soldner, Torsten

    2016-01-01

    The construction of the European Spallation Source ESS is ongoing in Lund, Sweden. This new high power spallation source with its long-pulse structure opens up new possibilities for fundamental physics experiments. This paper focusses on two proposals for fundamental physics at the ESS: The ANNI...

  20. Experimental studies of spallation on thin target

    International Nuclear Information System (INIS)

    Borne, F.; Crespin, S.; Drake, D.; Frehaut, J.; Ledoux, X.; Lochard, J.P.; Martinez, E.; Patin, Y.; Petibon, E.; Pras, Ph.; Boudard, A.; Legrain, R.; Leray, S.; Terrien, Y.; Bouyer, P.; Brochard, F.; Duchazeaubeneix, J.C.; Durand, J.M.; Meigo, S.I.; Milleret, G.; Thun, J.; Whittal, D.M.; Wlazlo, W.; Lebrun, C.; Lecolley, J.F.; Lecolley, F.R.; Lefebvres, F.; Louvel, M.; Varignon, C.; Menard, S.; Stugge, L.; Hanappe, F.

    2000-01-01

    Angular distribution of spallation neutrons induced by protons (0.8, 1.2 and 1.6 GeV) and deuterons (0.8 and 1.6 GeV beams on various thin targets have been measured at SATURNE (CEA Saclay/France) with two complementary experimental techniques: the time-of-flight measurement with tagged incident protons for low energy neutrons (2-400 MeV) and the use of a hydrogen converter associated are analysed, interpreted and finally compared with theoretical previsions of simulation codes using the TIERCE system including the intranuclear cascade codes of BERTINI and CUGNON. (authors)

  1. Status of Cea spallation modules for ads

    International Nuclear Information System (INIS)

    Enderle, R.; Poitevin, Y.; Deffain, J.P.; Bergeron, J.

    2001-01-01

    In the framework of CEA studies on ADS dedicated to waste transmutation, a liquid metal reference concept and an alternative solid target have been evaluated to produce neutrons inside the spallation module. This work examines the design (neutronic, thermohydraulic and mechanical aspects) and the performances of both options. It is shown that a liquid Pb-Bi target offers more possibilities regarding to high protons current densities (possible industrial extrapolation) but that a solid target made with tungsten particles offers also interesting ability to create a neutrons flux appropriated (strong spectrum and flat axial distribution) to an sub-critical core dedicated to incineration. (author)

  2. Sulfur and Moisture Effects on Alumina Scale and TBC Spallation

    Science.gov (United States)

    Smialek, James L.

    2007-01-01

    cause is related to a hydrogen embrittlement reaction: Al alloy + 3 H2O = Al(OH)3 + 3H(+) + 3e(-). This mechanism is derived from an analogous moisture-induced hydrogen embrittlement mechanism originally shown for Ni3Al and FeAl intermetallics. Consequently, a cathodic hydrogen charging technique was used to demonstrate that electrolytic de-scaling occurs for these otherwise adherent alumina scales formed on Y-doped Rene'N5, in support of hydrogen effects. Finally, some TBC observations are discussed in light of all of the above. Plasma sprayed 8YSZ coatings, produced on PWA1484 without a bond coat, were found to survive more than 1000 1-hr cycles at 1100 C when desulfurized to below 0.1 ppmw. At higher sulfur (1.2 ppmw) levels, moisture sensitivity and delayed TBC failure, referred to as Desk Top Spallation, occurred at just 200 hr. Despite a large degree of scatter, a factor of 5 in life improvement is indicated for desulfurized samples in cyclic furnace tests, confirming the beneficial effect of low sulfur alloys on model TBC systems. (DTS and moisture effects are also observed on commercially applied PVD 7YSZ coatings on Rene'N5+Y with Pt-aluminide bond coats). These types of catastrophic failure were subverted on the model system by segmenting the substrate into a network of 0.010 high ribs, spaced in. apart, prior to plasma spraying. No failures occurred after 1000 cycles at 1150 C or after 2000 cycles at 1100 C, even after water immersion. The benefit is described in terms of elasticity models and a critical buckling stress.

  3. Application of proton-induced X-ray emission technique to gunshot residue analyses

    International Nuclear Information System (INIS)

    Sen, P.; Panigrahi, N.; Rao, M.S.; Varier, K.M.; Sen, S.; Mehta, G.K.

    1982-01-01

    The proton-induced X-ray emission (PIXE) technique was applied to the identification and analysis of gunshot residues. Studies were made of the type of bullet and bullet hole identification, firearm discharge element profiles, the effect of various target backings, and hand swabbings. The discussion of the results reviews the sensitivity of the PIXE technique, its nondestructive nature, and its role in determining the distance from the gun to the victim and identifying the type of bullet used and whether a wound was made by a bullet or not. The high sensitivity of the PIXE technique, which is able to analyze samples as small as 0.1 to 1 ng, and its usefulness for detecting a variety of elements should make it particularly useful in firearms residue investigations

  4. Experimental Study of the Lead Tungstate Scintillator Proton-Induced Damage and Recovery

    CERN Document Server

    Auffray, Etiennette; Singovski , A

    2011-01-01

    Lead tungstate (PbWO4, or PWO) scintillating crystals are used by two of the four experiments at the Large Hadron Collider (LHC): 75848 in CMS and 17920 in ALICE. For the CMS electromagnetic calorimeter, one of the most important crystal properties is its radiation hardness. With the increase of luminosity, the radiation level will increase drastically, particularly in the high pseudorapidity regions of the calorimeter. Beside the effects of color-centre formation caused by gamma-radiation, additional measurable effect originated by hadron irradiation could appear, which will further deteriorate the optical transmission of the crystals and therefore their efficiency. In this paper, we will present results of the proton-induced damage in PWO and a study of optical transmission recovery at different temperatures and under different light-induced "bleaching" conditions for proton-irradiated crystals.

  5. The determination of light elements in heavy matrix using proton induced X-ray emission

    International Nuclear Information System (INIS)

    Levenets, V.V.; Omel'nik, A.P.; Shchur, A.A.; Chernov, A.E.; Usikov, N.P.; Zats, A.V.

    2007-01-01

    In this report the possibility of determination of light impurities in heavy matrixes is studied using proton induced X-Ray emission. The wide-band X-ray emission filter made from pyrolytic graphite was used in spectrometric scheme of experiment. The results of studying of filter features in energy range of X-ray emission from 4 to 12 keV were presented. The possibilities were examined of application of pyrolytic graphite filter to modify the X-rays spectrum for determination of iron, using characteristic emission of K-series, and hafnium, using L-series, in substances on base of zirconium (glasses, alloys etc.). It was shown, that the using of similar filter allows to reach the significant improving of metrological characteristics of analysis of mentioned impurities: the limits of detection of iron and hafnium were lowered single-order of magnitude. (authors)

  6. Standardization of proton-induced x-ray emission technique for analysis of thick samples

    Science.gov (United States)

    Ali, Shad; Zeb, Johar; Ahad, Abdul; Ahmad, Ishfaq; Haneef, M.; Akbar, Jehan

    2015-09-01

    This paper describes the standardization of the proton-induced x-ray emission (PIXE) technique for finding the elemental composition of thick samples. For the standardization, three different samples of standard reference materials (SRMs) were analyzed using this technique and the data were compared with the already known data of these certified SRMs. These samples were selected in order to cover the maximum range of elements in the periodic table. Each sample was irradiated for three different values of collected beam charges at three different times. A proton beam of 2.57 MeV obtained using 5UDH-II Pelletron accelerator was used for excitation of x-rays from the sample. The acquired experimental data were analyzed using the GUPIXWIN software. The results show that the SRM data and the data obtained using the PIXE technique are in good agreement.

  7. Proton induced x-ray emission analysis of trace elements in thick bread samples

    International Nuclear Information System (INIS)

    Mohamed Baker Al-bedri; Ikram Jameel Abdul Ghani; Ibrahim Abdul Rahman Al-aghil

    2009-01-01

    Proton induced X-ray emission (PIXE) technique has been used for identification and quantitative analysis of the elemental concentration in thick bread samples. Bread samples were air-oven dried at 60degC and milled in a clean agate mortar to homogenize the sample and pressed into a pellet. PIXE technique relies on the analysis of the energy spectra of the characteristic X-ray emitted from the thick bread sample and the orchard leaf standard (NIST-SRM-1571) bombarded with 2.0 MeV protons. The concentration of the elements (Cl, K, Ca, Mn, Fe, Cu, and Zn) in the bread samples was determined by comparison with NIST orchard leaf standard. The accuracy of the measurements ranged between ±2% and ±10% for the most elements detected in this method. The aim of this study is to establish the reference concentration of trace elements in the Iraqi bread using PIXE technique. (author)

  8. Linear scans of hair strands for trace elements by proton induced x-ray emission

    International Nuclear Information System (INIS)

    Jolly, R.K.; Pehrson, G.R.; Gupta, S.K.; Buckle, D.C.; Aceto, H. Jr.

    1974-01-01

    Hair strands obtained from school children in the 10 to 12 year age group were analyzed for trace element concentration as a function of distance from the root by proton-induced x-ray emission to study the history of exposure of the donors to toxic trace metals. These samples were collected from the vicinity of a copper smelter where high levels of As, Cd, Sb, and Pb have been noted. Scans show a continual build-up of Pb as a function of distance from the root, while As shows a reproducible and distinct maximum approximately 10 cm from the root. The concentration of Zn was found to be constant in all samples (without exception) to within the uncertainties of our measurements

  9. The US spallation neutron source (SNS) project

    International Nuclear Information System (INIS)

    Alonso, J.R.

    1999-01-01

    The SNS is a 1 MW pulsed spallation neutron source that will be sited at Oak Ridge. It will consist of a high-current, normal-conducting linac accelerating an H - beam to 1 GeV, an accumulator ring which compresses each 1 ms linac pulse into a 600 ns bunch which is then extracted in a single turn onto a liquid mercury target. Neutron pulses emerge at a 60 Hz rate from the two ambient, and two cryogenic moderators. Eighteen beam ports surrounding the target station are available for neutron-scattering instrumentation. Funds for ten instruments are included in the construction project; these instruments will provide basic measurement capability for the many and varied research activities at the SNS facility. The new spallation source is being built by a consortium of laboratories; the partners are LBNL, LANL, BNL, ANL and ORNL. The breadth and depth of experience and resources brought by such a wide-spread team offers very significant advantages. Construction will start in October of 1998, operation will begin in October, 2005. (J.P.N.)

  10. EURAC: A liquid target neutron spallation

    Energy Technology Data Exchange (ETDEWEB)

    Perlado, J.M.; Minguez, E.; Sanz, J. [Universidad Politecnica de Madrid (Spain)] [and others

    1995-10-01

    Euratom/JRC Ispra led some years ago the design of an accelerator based neutron spallation source EURAC, with special emphasis as a fusion material testing device. DENIM was involved in the development of the last version of this source. EURAC proposes to use a beam of 600 MeV or 1.5 GeV protons, produced by an effective and low cost ring cyclotron with a current of 6 mA impinging in a liquid lead, or lead-bismuth, target. It will use an advanced cyclotron technology which can be implemented in the next future, in the line of the actual technology of the upgraded SIN-type cyclotron. The adjacent rows to the target correspond to the lead, or Li{sub 17}Pb{sub 83}, cooled channels where the samples will be located. The available volumes there were shown enough for material testing purposes. Here, proposal of using those experimental areas to introduce small masses of radioactive wastes for testing of transmutation in spallation source is made. In addition, extrapolation of present conceptual design to make available larger volumes under flexible conditions seems to be possible. Neutrons leaking from the test zone drive a subcritical booster (<10 MW) which could provide a thermal neutron flux trap with a liquid hydrogen moderator in the center.

  11. Determination of proton-induced production cross sections and production rates of {sup 129}I from Te

    Energy Technology Data Exchange (ETDEWEB)

    Schnabel, C.; Lopez-Guitierrez, J.M.; Suter, M. [Eidgenoessische Technische Hochschule, Zurich (Switzerland); Synal, H.A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Gloris, M.; Leya, I.; Michel, R. [Hannover Univ. (Germany); Herpers, U. [Koeln Univ. (Germany)

    1997-09-01

    In order to model the production of {sup 129}I in meteoroids, proton-induced production cross sections in the medium range of {sup 129}I from Te as well as production from meteoroid simulation experiments have been determined. {sup 129}I is a very important cosmogenic nuclide to study the constancy of cosmic radiation on long time scales. (author) 2 figs., 2 refs.

  12. Study of spallation neutrons for the transmutation of long-lived nuclear waste

    International Nuclear Information System (INIS)

    Brochard, F.; Boyard, J.L.; Duchazeaubeneix, J.C.; Durand, J.M.; Faivre, J.C.; Leray, S.; Milleret, G.; Plouin, F.; Whittal, D.M.; Beau, M.; Crespin, S.; Frehaut, J.; Lochard, J.P.; Martinez, E.; Patin, Y.; Petitbon, E.; Sigaud, J.; Legrain, R.; Lepretre, A.; Terrien, Y.; Bacha, F.; Maillard, J.; Silva, J.

    1994-01-01

    With the renewed interest in accelerator-driven systems to transmute long-lived nuclear waste or to produce energy, new requirements for intermediate-energy nuclear data are now emerging. In all these systems, neutrons are produced by spallation reactions induced by around 1 GeV protons on a heavy target. These neutrons then drive a sub-critical blanket in which wastes are burned or energy is produced. A good knowledge of the spallation process (energy and angular distribution of the neutrons) is necessary to design and optimize the target-blanket system: for instance, to determine the best choices of beam energy, of composition and geometry of the target, in order to have the maximum neutron yield at the lowest cost, or to minimize the back-scattering of neutrons to the accelerator. A programme aimed at measuring the double differential cross-sections for the production of spallation neutrons induced by protons and deuterons GeV beams on different targets, is beginning at SATURNE. (authors). 3 refs., 3 figs

  13. Measurements of neutron spallation cross section. 2

    Energy Technology Data Exchange (ETDEWEB)

    Kim, E.; Nakamura, T. [Tohoku Univ., Sendai (Japan). Cyclotron and Radioisotope Center; Imamura, M.; Nakao, N.; Shibata, S.; Uwamino, Y.; Nakanishi, N.; Tanaka, Su.

    1997-03-01

    Neutron spallation cross section of {sup 59}Co(n,xn){sup 60-x}Co, {sup nat}Cu(n,sp){sup 56}Mn, {sup nat}Cu(n,sp){sup 58}Co, {sup nat}Cu(n,xn){sup 60}Cu, {sup nat}Cu(n,xn){sup 61}Cu and {sup nat}Cu(n,sp){sup 65}Ni was measured in the quasi-monoenergetic p-Li neutron fields in the energy range above 40 MeV which have been established at three AVF cyclotron facilities of (1) INS of Univ. of Tokyo, (2) TIARA of JAERI and (3) RIKEN. Our experimental data were compared with the ENDF/B-VI high energy file data by Fukahori and the calculated cross section data by Odano. (author)

  14. CFD analysis of the HYPER spallation target

    International Nuclear Information System (INIS)

    Cho, Chungho; Tak, Nam-il; Choi, Jae-Hyuk; Lee, Yong-Bum

    2008-01-01

    KAERI (Korea Atomic Energy Research Institute) is developing an accelerator driven system (ADS) named HYPER (HYbrid Power Extraction Reactor) for a transmutation of long-lived nuclear wastes. One of the challenging tasks for the HYPER system is to design a large spallation target with a beam power of 15-25 MW. The paper focuses on a thermal-hydraulic analysis of the active part of the HYPER target. Computational fluid dynamics (CFD) analysis was performed by using a commercial code CFX 5.7.1. Several advanced turbulence models with different grid structures were applied. The CFX results reveal a significant impact of the turbulence model on the window temperature. Particularly, the k-ε model predicts the lowest window temperature among the five investigated turbulence models

  15. Spallation neutron source target station issues

    International Nuclear Information System (INIS)

    Gabriel, T.A.; Barnes, J.N.; Charlton, L.A.

    1996-01-01

    In many areas of physics, materials and nuclear engineering, it is extremely valuable to have a very intense source of neutrons so that the structure and function of materials can be studied. One facility proposed for this purpose is the National Spallation Neutron Source (NSNS). This facility will consist of two parts: (1) a high-energy (∼1 GeV) and high powered (∼ 1 MW) proton accelerator, and (2) a target station which converts the protons to low-energy (≤ 2 eV) neutrons and delivers them to the neutron scattering instruments. This paper deals with the second part, i.e., the design and development of the NSNS target station and the scientifically challenging issues. Many scientific and technical disciplines are required to produce a successful target station. These include engineering, remote handling, neutronics, materials, thermal hydraulics, and instrumentation. Some of these areas will be discussed

  16. BNL feasibility studies of spallation neutron sources

    International Nuclear Information System (INIS)

    Lee, Y.Y.; Ruggiero, A.G.; Van Steenbergen, A.; Weng, W.T.

    1995-01-01

    This paper is the summary of conceptual design studies of a 5 MW Pulsed Spallation Neutron Source (PSNS) conducted by an interdepartmental study group at Brookhaven National Laboratory. The study was made of two periods. First, a scenario based on the use of a 600 MeV Linac followed by two fast-cycling 3.6 GeV Synchrotrons was investigated. Then, in a subsequent period, the attention of the study was directed toward an Accumulator scenario with two options: (1) a 1.25 GeV normal conducting Linac followed by two Accumulator Rings, and (2) a 2.4 GeV superconducting Linac followed by a single Accumulator Ring. The study did not make any reference to a specific site

  17. Radiochemical aspects of liquid mercury spallation targets

    CERN Document Server

    Neuhausen, Joerg; Eichler, Bernd; Eller, Martin; Horn, Susanne; Schumann, Dorothea; Stora, Thierry

    2012-01-01

    Liquid metal spallation targets using mercury as target material are used in state-of-the-art high power pulsed neutron sources that have been constructed in the USA and Japan within the last decade. Similar target concepts were also proposed for next generation ISOL, beta-beam and neutrino facilities. A large amount of radioactivity will be induced in the liquid metal during operation caused by the interaction of the target material with the intense proton beam. This radioactivity - carried by a wide range of radioisotopes of all the elements of the periodic table from hydrogen up to thallium - must be considered for the assessment of safe operation and maintenance procedures as well as for a final disposal of the used target material and components. This report presents an overview on chemical investigations performed in our laboratory that deal with the behavior of radionuclides in proton irradiated mercury samples. The solubility of elements in mercury was calculated using thermodynamical data obtained by...

  18. Accelerator driven reactors, - the significance of the energy distribution of spallation neutrons on the neutron statistics

    Energy Technology Data Exchange (ETDEWEB)

    Fhager, V

    2000-01-01

    In order to make correct predictions of the second moment of statistical nuclear variables, such as the number of fissions and the number of thermalized neutrons, the dependence of the energy distribution of the source particles on their number should be considered. It has been pointed out recently that neglecting this number dependence in accelerator driven systems might result in bad estimates of the second moment, and this paper contains qualitative and quantitative estimates of the size of these efforts. We walk towards the requested results in two steps. First, models of the number dependent energy distributions of the neutrons that are ejected in the spallation reactions are constructed, both by simple assumptions and by extracting energy distributions of spallation neutrons from a high-energy particle transport code. Then, the second moment of nuclear variables in a sub-critical reactor, into which spallation neutrons are injected, is calculated. The results from second moment calculations using number dependent energy distributions for the source neutrons are compared to those where only the average energy distribution is used. Two physical models are employed to simulate the neutron transport in the reactor. One is analytical, treating only slowing down of neutrons by elastic scattering in the core material. For this model, equations are written down and solved for the second moment of thermalized neutrons that include the distribution of energy of the spallation neutrons. The other model utilizes Monte Carlo methods for tracking the source neutrons as they travel inside the reactor material. Fast and thermal fission reactions are considered, as well as neutron capture and elastic scattering, and the second moment of the number of fissions, the number of neutrons that leaked out of the system, etc. are calculated. Both models use a cylindrical core with a homogenous mixture of core material. Our results indicate that the number dependence of the energy

  19. Accelerator driven reactors, - the significance of the energy distribution of spallation neutrons on the neutron statistics

    International Nuclear Information System (INIS)

    Fhager, V.

    2000-01-01

    In order to make correct predictions of the second moment of statistical nuclear variables, such as the number of fissions and the number of thermalized neutrons, the dependence of the energy distribution of the source particles on their number should be considered. It has been pointed out recently that neglecting this number dependence in accelerator driven systems might result in bad estimates of the second moment, and this paper contains qualitative and quantitative estimates of the size of these efforts. We walk towards the requested results in two steps. First, models of the number dependent energy distributions of the neutrons that are ejected in the spallation reactions are constructed, both by simple assumptions and by extracting energy distributions of spallation neutrons from a high-energy particle transport code. Then, the second moment of nuclear variables in a sub-critical reactor, into which spallation neutrons are injected, is calculated. The results from second moment calculations using number dependent energy distributions for the source neutrons are compared to those where only the average energy distribution is used. Two physical models are employed to simulate the neutron transport in the reactor. One is analytical, treating only slowing down of neutrons by elastic scattering in the core material. For this model, equations are written down and solved for the second moment of thermalized neutrons that include the distribution of energy of the spallation neutrons. The other model utilizes Monte Carlo methods for tracking the source neutrons as they travel inside the reactor material. Fast and thermal fission reactions are considered, as well as neutron capture and elastic scattering, and the second moment of the number of fissions, the number of neutrons that leaked out of the system, etc. are calculated. Both models use a cylindrical core with a homogenous mixture of core material. Our results indicate that the number dependence of the energy

  20. Proton-Induced X-Ray Emission Analysis of Crematorium Emissions

    Science.gov (United States)

    Ali, Salina; Nadareski, Benjamin; Yoskowitz, Joshua; Labrake, Scott; Vineyard, Michael

    2014-09-01

    There has been considerable debate in recent years about possible mercury emissions from crematoria due to amalgam tooth restorations. We have performed a proton-induced X-ray emission (PIXE) analysis of aerosol and soil samples taken near the Vale Cemetery Crematorium in Schenectady, NY, to address this concern. The aerosol samples were collected on the roof of the crematorium using a nine-stage, cascade impactor that separates the particulate matter by aerodynamic diameter and deposits it onto thin Kapton foils. The soil samples were collected at several different distances from the crematorium and compressed into pellets with a hydraulic press. The Kapton foils containing the aerosol samples and the soil pellets were bombarded with 2.2-MeV protons from the 1.1-MV tandem Pelletron accelerator in the Union College Ion-Beam Analysis Laboratory. We measured significant concentrations of sulfur, phosphorus, potassium, calcium, and iron, but essentially no mercury in the aerosol samples. The lower limit of detection for airborne mercury in this experiment was approximately 0.2 ng / m3. The PIXE analysis of the soil samples showed the presence of elements commonly found in soil (Si, K, Ca, Ti, Mn, Fe), but no trace of mercury. There has been considerable debate in recent years about possible mercury emissions from crematoria due to amalgam tooth restorations. We have performed a proton-induced X-ray emission (PIXE) analysis of aerosol and soil samples taken near the Vale Cemetery Crematorium in Schenectady, NY, to address this concern. The aerosol samples were collected on the roof of the crematorium using a nine-stage, cascade impactor that separates the particulate matter by aerodynamic diameter and deposits it onto thin Kapton foils. The soil samples were collected at several different distances from the crematorium and compressed into pellets with a hydraulic press. The Kapton foils containing the aerosol samples and the soil pellets were bombarded with 2.2-Me

  1. Strain rate effects for spallation of concrete

    Science.gov (United States)

    Häussler-Combe, Ulrich; Panteki, Evmorfia; Kühn, Tino

    2015-09-01

    Appropriate triaxial constitutive laws are the key for a realistic simulation of high speed dynamics of concrete. The strain rate effect is still an open issue within this context. In particular the question whether it is a material property - which can be covered by rate dependent stress strain relations - or mainly an effect of inertia is still under discussion. Experimental and theoretical investigations of spallation of concrete specimen in a Hopkinson Bar setup may bring some evidence into this question. For this purpose the paper describes the VERD model, a newly developed constitutive law for concrete based on a damage approach with included strain rate effects [1]. In contrast to other approaches the dynamic strength increase is not directly coupled to strain rate values but related to physical mechanisms like the retarded movement of water in capillary systems and delayed microcracking. The constitutive law is fully triaxial and implemented into explicit finite element codes for the investigation of a wide range of concrete structures exposed to impact and explosions. The current setup models spallation experiments with concrete specimen [2]. The results of such experiments are mainly related to the dynamic tensile strength and the crack energy of concrete which may be derived from, e.g., the velocity of spalled concrete fragments. The experimental results are compared to the VERD model and two further constitutive laws implemented in LS-Dyna. The results indicate that both viscosity and retarded damage are required for a realistic description of the material behaviour of concrete exposed to high strain effects [3].

  2. Strain rate effects for spallation of concrete

    Directory of Open Access Journals (Sweden)

    Häussler-Combe Ulrich

    2015-01-01

    Full Text Available Appropriate triaxial constitutive laws are the key for a realistic simulation of high speed dynamics of concrete. The strain rate effect is still an open issue within this context. In particular the question whether it is a material property – which can be covered by rate dependent stress strain relations – or mainly an effect of inertia is still under discussion. Experimental and theoretical investigations of spallation of concrete specimen in a Hopkinson Bar setup may bring some evidence into this question. For this purpose the paper describes the VERD model, a newly developed constitutive law for concrete based on a damage approach with included strain rate effects [1]. In contrast to other approaches the dynamic strength increase is not directly coupled to strain rate values but related to physical mechanisms like the retarded movement of water in capillary systems and delayed microcracking. The constitutive law is fully triaxial and implemented into explicit finite element codes for the investigation of a wide range of concrete structures exposed to impact and explosions. The current setup models spallation experiments with concrete specimen [2]. The results of such experiments are mainly related to the dynamic tensile strength and the crack energy of concrete which may be derived from, e.g., the velocity of spalled concrete fragments. The experimental results are compared to the VERD model and two further constitutive laws implemented in LS-Dyna. The results indicate that both viscosity and retarded damage are required for a realistic description of the material behaviour of concrete exposed to high strain effects [3].

  3. Radiation physics of high power spallation targets. State of the art simulation methods and experiments, the 'European Spallation Source' (ESS)

    International Nuclear Information System (INIS)

    Filges, D.; Cloth, P.; Neef, R.D.; Schaal, H.

    1998-01-01

    Particle transport and nuclear interactions of planned high power spallation targets with GeV proton beams can be simulated using widely developed Monte Carlo transport methods. This includes available high energy radiation transport codes and systems for low energy, earlier developed for reactor physics and fusion technology. Monte Carlo simulation codes and applied methods are discussed. The capabilities of the world-wide existing state-of-the-art computer code systems are demonstrated. Results of computational studies for the 'European Spallation Source' (ESS) mercury high power target station are given. The needs for spallation related data and planned experiments are shown. (author)

  4. Department of Nuclear Reaction - Overview

    International Nuclear Information System (INIS)

    Budzanowski, A.

    2001-01-01

    asymmetry. The same effects can be crucial for the extraction of polarized quark distributions (spin puzzle) from semi-inclusive production of pions in DIS. It was carefully studied how production of dijets in real and virtual photoproduction provides new information on unintegrated gluon distribution. We have completed the construction of the Forward Wall detector for the CHICSi experiment at the Celsius synchrotron. First tests with 20 Ne beam at 200 MeV/nucleon on 40 Ar and 14 N targets were performed. New results on the formation of dtμ, Muonic Molecule in Solid Hydrogen Target were obtained. First tests of the low energy spallation apparatus for measuring low energy spallation products emitted in proton induced reactions were performed using accelerator facilities at Catania (Italy). Further studies of statistical aspects of nuclear coupling to continuum were pursued. It was found that in the region of higher density of states the coupling to continuum is consistent with the statistical model. One Ph.D. thesis was completed under the supervision of Prof. Drozdz. The newly born doctor J. Kwapien was awarded The Henryk Niewodniczanski prize for his scientific achievement in studying the brain function. (author)

  5. Deep spallation of medium mass isotopes by protons

    International Nuclear Information System (INIS)

    Kolsky, K.L.; Karol, P.J.

    1993-01-01

    Spallation systematics have been extended into the deep spallation mass region. Production cross sections of scandium radioisotopes from 0.8 GeV protons on 89 Y, 92,96,100 Mo, and 130 Te targets were measured and the cross sections were used to generate isobaric yield curves at A p =47. In the latter target, this corresponds to a mass loss of >80 nucleons. At ∼10 MeV/nucleon and for products outside the multifragmentation region, this is an extreme manifestation of the spallation process. The results prove to fit smooth extrapolations from trends developed in earlier work on less deep spallation. The influence of target composition is still evident even from 130 Te, in contrast to expectations, based on evaporation considerations, that this so-called memory effect would wash out

  6. Invited talks (Abstracts only) The spallation neutron source: New ...

    Indian Academy of Sciences (India)

    The spallation neutron source (SNS) facility became operational in the spring of 2006, and is ... torate at ORNL providing the opportunity to develop science and instrumentation pro- ... tion, information technology, biotechnology, and health.

  7. Proceedings of the international workshop on spallation materials technology

    International Nuclear Information System (INIS)

    Mansur, L.K.; Ullmaier, H.

    1996-01-01

    This document contains papers which were presented at the International Workshop on Spallation Materials Technology. Topics included: overviews and thermal response; operational experience; materials experience; target station and component design; particle transport and damage calculations; neutron sources; and compatibility

  8. Proceedings of the international workshop on spallation materials technology

    Energy Technology Data Exchange (ETDEWEB)

    Mansur, L.K.; Ullmaier, H. [comps.

    1996-10-01

    This document contains papers which were presented at the International Workshop on Spallation Materials Technology. Topics included: overviews and thermal response; operational experience; materials experience; target station and component design; particle transport and damage calculations; neutron sources; and compatibility.

  9. Universal odd-even staggering in isotopic fragmentation and spallation cross sections of neutron-rich fragments

    Science.gov (United States)

    Mei, B.; Tu, X. L.; Wang, M.

    2018-04-01

    An evident odd-even staggering (OES) in fragment cross sections has been experimentally observed in many fragmentation and spallation reactions. However, quantitative comparisons of this OES effect in different reaction systems are still scarce for neutron-rich nuclei near the neutron drip line. By employing a third-order difference formula, the magnitudes of this OES in extensive experimental cross sections are systematically investigated for many neutron-rich nuclei with (N -Z ) from 1 to 23 over a broad range of atomic numbers (Z ≈3 -50 ). A comparison of these magnitude values extracted from fragment cross sections measured in different fragmentation and spallation reactions with a large variety of projectile-target combinations over a wide energy range reveals that the OES magnitude is almost independent of the projectile-target combinations and the projectile energy. The weighted average of these OES magnitudes derived from cross sections accurately measured in different reaction systems is adopted as the evaluation value of the OES magnitude. These evaluated OES magnitudes are recommended to be used in fragmentation and spallation models to improve their predictions for fragment cross sections.

  10. Proton induced X-Ray fluorescence study as a tool trace element analysis

    International Nuclear Information System (INIS)

    El-Kady, Ahmed A.

    1978-01-01

    Usefulness and limitations of trace elemental analysis by high energy charged particles and photon induced X-ray have been discussed. Comparison with the well established neutron activation analysis technique is also given. Back-ground radiation due to bremsstrahlung from secondary electrons and due to charged particle bremsstrahlung have been reviewed for different projectiles. The sensitivity of elemental analysis by proton induced X-ray fluorescence have been examined by measuring the characteristic X-ray emission cross section for K and L transitions of many elements and for different proton energies and compared with theroretical values. The discussion given in this report show that with suitable proton generator and a high resolution X-ray detector, proton X-ray fluorescence technique is capable of analyzing many elements simultaneously at the part per million level and offers a rapid and reliable method for trace element analysis. Data on water, blood and tissue samples given in this report are few examples of many possible applications

  11. Fast simulation of Proton Induced X-Ray Emission Tomography using CUDA

    Energy Technology Data Exchange (ETDEWEB)

    Beasley, D.G., E-mail: dgbeasley@itn.pt; Marques, A.C.; Alves, L.C.; Silva, R.C. da

    2013-07-01

    A new 3D Proton Induced X-Ray Emission Tomography (PIXE-T) and Scanning Transmission Ion Microscopy Tomography (STIM-T) simulation software has been developed in Java and uses NVIDIA™ Common Unified Device Architecture (CUDA) to calculate the X-ray attenuation for large detector areas. A challenge with PIXE-T is to get sufficient counts while retaining a small beam spot size. Therefore a high geometric efficiency is required. However, as the detector solid angle increases the calculations required for accurate reconstruction of the data increase substantially. To overcome this limitation, the CUDA parallel computing platform was used which enables general purpose programming of NVIDIA graphics processing units (GPUs) to perform computations traditionally handled by the central processing unit (CPU). For simulation performance evaluation, the results of a CPU- and a CUDA-based simulation of a phantom are presented. Furthermore, a comparison with the simulation code in the PIXE-Tomography reconstruction software DISRA (A. Sakellariou, D.N. Jamieson, G.J.F. Legge, 2001) is also shown. Compared to a CPU implementation, the CUDA based simulation is approximately 30× faster.

  12. Fast simulation of Proton Induced X-Ray Emission Tomography using CUDA

    International Nuclear Information System (INIS)

    Beasley, D.G.; Marques, A.C.; Alves, L.C.; Silva, R.C. da

    2013-01-01

    A new 3D Proton Induced X-Ray Emission Tomography (PIXE-T) and Scanning Transmission Ion Microscopy Tomography (STIM-T) simulation software has been developed in Java and uses NVIDIA™ Common Unified Device Architecture (CUDA) to calculate the X-ray attenuation for large detector areas. A challenge with PIXE-T is to get sufficient counts while retaining a small beam spot size. Therefore a high geometric efficiency is required. However, as the detector solid angle increases the calculations required for accurate reconstruction of the data increase substantially. To overcome this limitation, the CUDA parallel computing platform was used which enables general purpose programming of NVIDIA graphics processing units (GPUs) to perform computations traditionally handled by the central processing unit (CPU). For simulation performance evaluation, the results of a CPU- and a CUDA-based simulation of a phantom are presented. Furthermore, a comparison with the simulation code in the PIXE-Tomography reconstruction software DISRA (A. Sakellariou, D.N. Jamieson, G.J.F. Legge, 2001) is also shown. Compared to a CPU implementation, the CUDA based simulation is approximately 30× faster

  13. Proton beam characterization by proton-induced acoustic emission: simulation studies

    International Nuclear Information System (INIS)

    Jones, K C; Witztum, A; Avery, S; Sehgal, C M

    2014-01-01

    Due to their Bragg peak, proton beams are capable of delivering a targeted dose of radiation to a narrow volume, but range uncertainties currently limit their accuracy. One promising beam characterization technique, protoacoustic range verification, measures the acoustic emission generated by the proton beam. We simulated the pressure waves generated by proton radiation passing through water. We observed that the proton-induced acoustic signal consists of two peaks, labeled α and γ, with two originating sources. The α acoustic peak is generated by the pre-Bragg peak heated region whereas the source of the γ acoustic peak is the proton Bragg peak. The arrival time of the α and γ peaks at a transducer reveals the distance from the beam propagation axis and Bragg peak center, respectively. The maximum pressure is not observed directly above the Bragg peak due to interference of the acoustic signals. Range verification based on the arrival times is shown to be more effective than determining the Bragg peak position based on pressure amplitudes. The temporal width of the α and γ peaks are linearly proportional to the beam diameter and Bragg peak width, respectively. The temporal separation between compression and rarefaction peaks is proportional to the spill time width. The pressure wave expected from a spread out Bragg peak dose is characterized. The simulations also show that acoustic monitoring can verify the proton beam dose distribution and range by characterizing the Bragg peak position to within ∼1 mm. (paper)

  14. Some results of applied spallation physics research at Los Alamos

    International Nuclear Information System (INIS)

    Russell, G.J.; Gilmore, J.S.

    1983-01-01

    At the Los Alamos National Laboratory, we have an active effort in the general area of Applied Spallation Physics Research. The main emphasis of this activity has been on obtaining basic data relevant to spallation neutron source development, accelerator breeder technology, and validation of computer codes used in these applications. We present here an overview of our research effort and show some measured and calculated results of differential and clean integral experiments

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

    International Nuclear Information System (INIS)

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

    1991-01-01

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

  16. Measurement and Simulation of the Variation in Proton-Induced Energy Deposition in Large Silicon Diode Arrays

    Science.gov (United States)

    Howe, Christina L.; Weller, Robert A.; Reed, Robert A.; Sierawski, Brian D.; Marshall, Paul W.; Marshall, Cheryl J.; Mendenhall, Marcus H.; Schrimpf, Ronald D.

    2007-01-01

    The proton induced charge deposition in a well characterized silicon P-i-N focal plane array is analyzed with Monte Carlo based simulations. These simulations include all physical processes, together with pile up, to accurately describe the experimental data. Simulation results reveal important high energy events not easily detected through experiment due to low statistics. The effects of each physical mechanism on the device response is shown for a single proton energy as well as a full proton space flux.

  17. Application of proton induced x-ray emission (PIXE) in estimation of trace metals entrapped in silica matrix

    International Nuclear Information System (INIS)

    Jal, P.K.; Patel, Sabita; Mishra, B.K.; Sudarshan, M.; Saha, A.

    2005-01-01

    Proton induced x-ray emission technique is used for multielemental analysis of metal ions adsorbed on nanosilica surface. At pH 3.5, silica traps uranium selectively from a mixture of solutions of 13 different metal ions viz., K(I), Ca(II), Fe(III), Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Sr(II), Cd(II). Ba(II), Hg(II) and UO 2 (VI). (author)

  18. Study of spallation residues of gold at 0.8 GeV/N in reverse kinematics

    International Nuclear Information System (INIS)

    Tassan-Got, L.; Mustapha, B.; Rejmund, F.

    2000-01-01

    Spallation residue cross-sections of gold have been measured in reverse kinematics. For the first time isotopic distributions have been obtained for such a heavy nucleus at a level of accuracy of 10 %. When compared to model calculations the results appear to be very sensitive to the distribution of excitation energy in the fast step of the reaction. This allows an insight on the mechanism of the energy and momentum deposition. (authors)

  19. Experimental studies of spallation on thin target; Etudes experimentales de la spallation en cible mince

    Energy Technology Data Exchange (ETDEWEB)

    Borne, F.; Crespin, S.; Drake, D.; Frehaut, J.; Ledoux, X.; Lochard, J.P.; Martinez, E.; Patin, Y.; Petibon, E.; Pras, Ph. [CEA/DAM-Ile de France, Dept. de Physique Theorique et Appliquee, DPTA, 91 - Bruyeres-Le-Chatel (France); Boudard, A.; Legrain, R.; Leray, S.; Terrien, Y. [CEA/Saclay, Dept. d' Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l' Instrumentation Associee, DAPNIA, 91 - Gif-sur-Yvette (France); Bouyer, P.; Brochard, F.; Duchazeaubeneix, J.C.; Durand, J.M.; Meigo, S.I.; Milleret, G.; Thun, J.; Whittal, D.M.; Wlazlo, W. [Laboratoire National Saturne - Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France); Lebrun, C.; Lecolley, J.F.; Lecolley, F.R.; Lefebvres, F.; Louvel, M.; Varignon, C. [Caen Univ., Lab. de Physique Corpusculaire, 14 (France); Menard, S. [Institut de Physique Nucleaire, IN2P3/CNRS, 91 - Orsay (France); Stugge, L. [Institut de Recherches Subatomiques, IReS, 67 - Strasbourg (France); Hanappe, F. [IIM, Bruxelles (Belgium)

    2000-07-01

    Angular distribution of spallation neutrons induced by protons (0.8, 1.2 and 1.6 GeV) and deuterons (0.8 and 1.6 GeV) beams on various thin targets have been measured at SATURNE (CEA Saclay/France) with two complementary experimental techniques: the time-of-flight measurement with tagged incident protons for low energy neutrons (2-400 MeV) and the use of a hydrogen converter associated are analysed, interpreted and finally compared with theoretical previsions of simulation codes using the TIERCE system including the intranuclear cascade codes of BERTINI and CUGNON. (authors)

  20. Reference Cross Sections for Charged-particle Monitor Reactions

    Czech Academy of Sciences Publication Activity Database

    Hermanne, A.; Ignatyuk, A. V.; Capote, R.; Carlson, B. V.; Engle, J. W.; Kellett, M. A.; Kibédi, T.; Kim, G.; Kondev, F. G.; Hussain, M.; Lebeda, Ondřej; Luca, A.; Nagai, Y.; Naik, H.; Nichols, A. L.; Nortier, F. M.; Suryanarayana, S. V.; Takacs, S.; Tarkanyi, F. T.; Verpelli, M.

    2018-01-01

    Roč. 148, SI (2018), s. 338-382 ISSN 0090-3752 Institutional support: RVO:61389005 Keywords : deuteron induced reactions * proton induced reactions * cross sections Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders OBOR OECD: Nuclear physics Impact factor: 1.146, year: 2016

  1. Proton induced target fragmentation studies on solid state nuclear track detectors using Carbon radiators

    Science.gov (United States)

    Szabó, J.; Pálfalvi, J. K.; Strádi, A.; Bilski, P.; Swakoń, J.; Stolarczyk, L.

    2018-04-01

    One of the limiting factors of an astronaut's career is the dose received from space radiation. High energy protons, being the main components of the complex radiation field present on a spacecraft, give a significant contribution to the dose. To investigate the behavior of solid state nuclear track detectors (SSNTDs) if they are irradiated by such particles, SSNTD stacks containing carbon blocks were exposed to high energy proton beams (70, 100, 150 and 230 MeV) at the Proteus cyclotron, IFJ PAN -Krakow. The incident protons cannot be detected directly; however, tracks of secondary particles, recoils and fragments of the constituent atoms of the detector material and of the carbon radiator are formed. It was found that as the proton energy increases, the number of tracks induced in the PADC material by secondary particles decreases. From the measured geometrical parameters of the tracks the linear energy transfer (LET) spectrum and the dosimetric quantities were determined, applying appropriate calibration. In the LET spectra the LET range of the most important secondary particles could be identified and their abundance showed differences in the spectra if the detectors were short or long etched. The LET spectra obtained on the SSNTDs irradiated by protons were compared to LET spectra of detectors flown on the International Space Station (ISS): they were quite similar, resulting in a quality factor difference of only 5%. Thermoluminescent detectors (TLDs) were applied in each case to measure the dose from primary protons and other lower LET particles present in space. Comparing and analyzing the results of the TLD and SSNTD measurements, it was obtained that proton induced target fragments contributed to the total absorbed dose in 3.2% and to the dose equivalent in 14.2% in this particular space experiment.

  2. Reaction

    African Journals Online (AJOL)

    abp

    19 oct. 2017 ... Reaction to Mohamed Said Nakhli et al. concerning the article: "When the axillary block remains the only alternative in a 5 year old child". .... Bertini L1, Savoia G, De Nicola A, Ivani G, Gravino E, Albani A et al ... 2010;7(2):101-.

  3. Spallation nucleosynthesis by accelerated charged-particles

    International Nuclear Information System (INIS)

    Goriely, S.

    2008-01-01

    Recent observations have suggested the presence of radioactive elements, such as Pm and 84≤Z≤99 elements) at the surface of the magnetic star HD101065, also known as Przybylski's star. This star is know to be a chemically peculiar star and its anomalous 38 30 heavy elements can be achieved. In this nucleosynthesis process, the secondary-neutron captures play a crucial role. The most attractive feature of the spallation process is the systematic production of Pm and Tc and the possible synthesis of actinides and sub-actinides.Based on such a parametric model, it is also shown that intense fluences of accelerated charged-particles interacting with surrounding material can efficiently produce elements heavier than iron. Different regimes are investigated and shown to be at the origin of p- and s-nuclei in the case of high-fluence low-flux events and r-nuclei for high-fluence high-flux irradiations. The possible existence of such irradiation events need to be confirmed by hydrodynamics simulations, but most of all by spectroscopic observations through the detection of short-lived radio-elements

  4. The Spallation Neutron Source accelerator system design

    Science.gov (United States)

    Henderson, S.; Abraham, W.; Aleksandrov, A.; Allen, C.; Alonso, J.; Anderson, D.; Arenius, D.; Arthur, T.; Assadi, S.; Ayers, J.; Bach, P.; Badea, V.; Battle, R.; Beebe-Wang, J.; Bergmann, B.; Bernardin, J.; Bhatia, T.; Billen, J.; Birke, T.; Bjorklund, E.; Blaskiewicz, M.; Blind, B.; Blokland, W.; Bookwalter, V.; Borovina, D.; Bowling, S.; Bradley, J.; Brantley, C.; Brennan, J.; Brodowski, J.; Brown, S.; Brown, R.; Bruce, D.; Bultman, N.; Cameron, P.; Campisi, I.; Casagrande, F.; Catalan-Lasheras, N.; Champion, M.; Champion, M.; Chen, Z.; Cheng, D.; Cho, Y.; Christensen, K.; Chu, C.; Cleaves, J.; Connolly, R.; Cote, T.; Cousineau, S.; Crandall, K.; Creel, J.; Crofford, M.; Cull, P.; Cutler, R.; Dabney, R.; Dalesio, L.; Daly, E.; Damm, R.; Danilov, V.; Davino, D.; Davis, K.; Dawson, C.; Day, L.; Deibele, C.; Delayen, J.; DeLong, J.; Demello, A.; DeVan, W.; Digennaro, R.; Dixon, K.; Dodson, G.; Doleans, M.; Doolittle, L.; Doss, J.; Drury, M.; Elliot, T.; Ellis, S.; Error, J.; Fazekas, J.; Fedotov, A.; Feng, P.; Fischer, J.; Fox, W.; Fuja, R.; Funk, W.; Galambos, J.; Ganni, V.; Garnett, R.; Geng, X.; Gentzlinger, R.; Giannella, M.; Gibson, P.; Gillis, R.; Gioia, J.; Gordon, J.; Gough, R.; Greer, J.; Gregory, W.; Gribble, R.; Grice, W.; Gurd, D.; Gurd, P.; Guthrie, A.; Hahn, H.; Hardek, T.; Hardekopf, R.; Harrison, J.; Hatfield, D.; He, P.; Hechler, M.; Heistermann, F.; Helus, S.; Hiatt, T.; Hicks, S.; Hill, J.; Hill, J.; Hoff, L.; Hoff, M.; Hogan, J.; Holding, M.; Holik, P.; Holmes, J.; Holtkamp, N.; Hovater, C.; Howell, M.; Hseuh, H.; Huhn, A.; Hunter, T.; Ilg, T.; Jackson, J.; Jain, A.; Jason, A.; Jeon, D.; Johnson, G.; Jones, A.; Joseph, S.; Justice, A.; Kang, Y.; Kasemir, K.; Keller, R.; Kersevan, R.; Kerstiens, D.; Kesselman, M.; Kim, S.; Kneisel, P.; Kravchuk, L.; Kuneli, T.; Kurennoy, S.; Kustom, R.; Kwon, S.; Ladd, P.; Lambiase, R.; Lee, Y. Y.; Leitner, M.; Leung, K.-N.; Lewis, S.; Liaw, C.; Lionberger, C.; Lo, C. C.; Long, C.; Ludewig, H.; Ludvig, J.; Luft, P.; Lynch, M.; Ma, H.; MacGill, R.; Macha, K.; Madre, B.; Mahler, G.; Mahoney, K.; Maines, J.; Mammosser, J.; Mann, T.; Marneris, I.; Marroquin, P.; Martineau, R.; Matsumoto, K.; McCarthy, M.; McChesney, C.; McGahern, W.; McGehee, P.; Meng, W.; Merz, B.; Meyer, R.; Meyer, R.; Miller, B.; Mitchell, R.; Mize, J.; Monroy, M.; Munro, J.; Murdoch, G.; Musson, J.; Nath, S.; Nelson, R.; Nelson, R.; O`Hara, J.; Olsen, D.; Oren, W.; Oshatz, D.; Owens, T.; Pai, C.; Papaphilippou, I.; Patterson, N.; Patterson, J.; Pearson, C.; Pelaia, T.; Pieck, M.; Piller, C.; Plawski, T.; Plum, M.; Pogge, J.; Power, J.; Powers, T.; Preble, J.; Prokop, M.; Pruyn, J.; Purcell, D.; Rank, J.; Raparia, D.; Ratti, A.; Reass, W.; Reece, K.; Rees, D.; Regan, A.; Regis, M.; Reijonen, J.; Rej, D.; Richards, D.; Richied, D.; Rode, C.; Rodriguez, W.; Rodriguez, M.; Rohlev, A.; Rose, C.; Roseberry, T.; Rowton, L.; Roybal, W.; Rust, K.; Salazer, G.; Sandberg, J.; Saunders, J.; Schenkel, T.; Schneider, W.; Schrage, D.; Schubert, J.; Severino, F.; Shafer, R.; Shea, T.; Shishlo, A.; Shoaee, H.; Sibley, C.; Sims, J.; Smee, S.; Smith, J.; Smith, K.; Spitz, R.; Staples, J.; Stein, P.; Stettler, M.; Stirbet, M.; Stockli, M.; Stone, W.; Stout, D.; Stovall, J.; Strelo, W.; Strong, H.; Sundelin, R.; Syversrud, D.; Szajbler, M.; Takeda, H.; Tallerico, P.; Tang, J.; Tanke, E.; Tepikian, S.; Thomae, R.; Thompson, D.; Thomson, D.; Thuot, M.; Treml, C.; Tsoupas, N.; Tuozzolo, J.; Tuzel, W.; Vassioutchenko, A.; Virostek, S.; Wallig, J.; Wanderer, P.; Wang, Y.; Wang, J. G.; Wangler, T.; Warren, D.; Wei, J.; Weiss, D.; Welton, R.; Weng, J.; Weng, W.-T.; Wezensky, M.; White, M.; Whitlatch, T.; Williams, D.; Williams, E.; Wilson, K.; Wiseman, M.; Wood, R.; Wright, P.; Wu, A.; Ybarrolaza, N.; Young, K.; Young, L.; Yourd, R.; Zachoszcz, A.; Zaltsman, A.; Zhang, S.; Zhang, W.; Zhang, Y.; Zhukov, A.

    2014-11-01

    The Spallation Neutron Source (SNS) was designed and constructed by a collaboration of six U.S. Department of Energy national laboratories. The SNS accelerator system consists of a 1 GeV linear accelerator and an accumulator ring providing 1.4 MW of proton beam power in microsecond-long beam pulses to a liquid mercury target for neutron production. The accelerator complex consists of a front-end negative hydrogen-ion injector system, an 87 MeV drift tube linear accelerator, a 186 MeV side-coupled linear accelerator, a 1 GeV superconducting linear accelerator, a 248-m circumference accumulator ring and associated beam transport lines. The accelerator complex is supported by ~100 high-power RF power systems, a 2 K cryogenic plant, ~400 DC and pulsed power supply systems, ~400 beam diagnostic devices and a distributed control system handling ~100,000 I/O signals. The beam dynamics design of the SNS accelerator is presented, as is the engineering design of the major accelerator subsystems.

  5. Synchrotron based spallation neutron source concepts

    International Nuclear Information System (INIS)

    Cho, Y.

    1998-01-01

    During the past 20 years, rapid-cycling synchrotrons (RCS) have been used very productively to generate short-pulse thermal neutron beams for neutron scattering research by materials science communities in Japan (KENS), the UK (ISIS) and the US (IPNS). The most powerful source in existence, ISIS in the UK, delivers a 160-kW proton beam to a neutron-generating target. Several recently proposed facilities require proton beams in the MW range to produce intense short-pulse neutron beams. In some proposals, a linear accelerator provides the beam power and an accumulator ring compresses the pulse length to the required ∼ 1 micros. In others, RCS technology provides the bulk of the beam power and compresses the pulse length. Some synchrotron-based proposals achieve the desired beam power by combining two or more synchrotrons of the same energy, and others propose a combination of lower and higher energy synchrotrons. This paper presents the rationale for using RCS technology, and a discussion of the advantages and disadvantages of synchrotron-based spallation sources

  6. The European Spallation Source (ESS) project

    International Nuclear Information System (INIS)

    Clausen, K.N.

    2001-01-01

    The European Spallation Source (ESS) is a proposal for a next generation neutron source in Europe. The first phase of the project - establishing the scientific case and the technical feasibility - is now followed by an intensive period of R and D activities. Three target station options: l) a 5 MW 50 Hz short pulse station, 2) a 1 MW 10 Hz short pulse station and 3) a 4 to 5 MW 16 2/3 Hz 2.5 ms long pulse station, and the use of novel advanced cold moderators will be studied. A superconducting option for the accelerator will be investigated in a Europe-wide feasibility study for a multipurpose facility (CONCERT) with potential applications in areas such as neutron scattering, high power irradiation, R and D on transmutation and radioactive beams. It will explore possible synergies of such a facility compared with a standalone solution for the ESS. The milestones for the next three years are: June 2001 - Decision on neutron parameters and target station options, June 2002 - Conclusion of the Concert multipurpose accelerator study and June 2003 - Proposal ready for submission to funding agencies. The facility could be ready for operation around 2010. (author)

  7. Theoretical estimation of proton induced X-ray emission yield of the trace elements present in the lung and breast cancer

    International Nuclear Information System (INIS)

    Manjunatha, H.C.; Sowmya, N.

    2013-01-01

    X-rays may be produced following the excitation of target atoms induced by an energetic incident ion beam of protons. Proton induced X-ray emission (PIXE) analysis has been used for many years for the determination of elemental composition of materials using X-rays. Recent interest in the proton induced X-ray emission cross section has arisen due to their importance in the rapidly expanding field of PIXE analysis. One of the steps in the analysis is to fit the measured X-ray spectrum with theoretical spectrum. The theoretical cross section and yields are essential for the evaluation of spectrum. We have theoretically evaluated the PIXE cross sections for trace elements in the lung and breast cancer tissues such as Cl, K, Ca,Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, P, S, Sr, Hg and Pb. The estimated cross section is used in the evaluation of Proton induced X-ray emission spectrum for the given trace elements.We have also evaluated the Proton induced X-ray emission yields in the thin and thick target of the given trace elements. The evaluated Proton induced X-ray emission cross-section, spectrum and yields are graphically represented. Some of these values are also tabulated. Proton induced X-ray emission cross sections and a yield for the given trace elements varies with the energy. PIXE yield depends on a real density and does not on thickness of the target. (author)

  8. Measurement of 0.8 and 1.5 GeV proton induced neutron production cross sections at 0deg

    International Nuclear Information System (INIS)

    Shigyo, Nobuhiro; Kunieda, Satoshi; Watanabe, Takehito; Ishibashi, Kenji; Satoh, Daiki; Meigo, Shin-ichiro

    2004-01-01

    Neutron-production double-differential cross sections at 0deg were measured for proton-induced reactions on Fe and Pb targets at 0.8 and 1.5 GeV. The experiment was performed at the π2 beam line of the 12 GeV proton synchrotron in High Energy Accelerator Research Organization (KEK). Neutrons were measured by time-of-flight technique with two different flight path lengths, i.e. 3.5 and 5.0 m at 0.8 and 1.5 GeV, respectively. NE213 liquid organic scintillators 12.7 cm in diameter and 12.7 cm in thickness were set at 0deg as neutron detector. For the improvement of the energy resolution, the scintillator was connected with three Hamamatsu H2431 photomultipliers 5.1 cm in diameter. The neutron detection efficiencies were obtained by the SCINFUL-QMD code. The experimental data were compared with the calculation results of the intranuclear-cascade-evaporation (INC/E) and the quantum-molecular-dynamics (QMD) models. (author)

  9. Measurement of isotopic cross sections of spallation residues in 800 A MeV {sup 197}Au + p collisions

    Energy Technology Data Exchange (ETDEWEB)

    Rejmund, F.; Mustapha, B.; Bernas, M.; Stephan, C.; Taieb, J.; Tassan-Got, L. [Institut de Physique Nucleaire, (IN2P3/CNRS) 91 - Orsay (France); Armbruster, P.; Benlliure, J.; Enqvist, T.; Schmidt, K.H.; Taieb, J. [GSI, Planckstrasse, Darmstadt (Germany); Benlliure, J. [Universidad de Santiago de Compostela (Spain); Boudard, A.; Legrain, R.; Leray, S.; Volant, C. [CEA/Saclay, Dept. d' Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l' Instrumentation Associee (DAPNIA), 91 - Gif-sur-Yvette (France); Dufour, J.P. [CENBG, IN2P3, 33 - Gradignan (France)

    2000-07-01

    The spallation of {sup 197}Au by 800 MeV protons was investigated in inverse kinematics at GSI, Darmstadt, by use of a {sup 197}Au beam bombarding a liquid-hydrogen target. The fragment separator (FRS) was used to select and identify the reaction products prior to {beta} decay. The individual production cross sections and the kinematical properties of 396 isotopes for all elements between mercury (Z=80) and neodymium (Z=60) have been measured. A comparison with Monte Carlo calculations based on different two-step models of the spallation reaction is given. The shape of the isotopic distributions close to the projectile is found to differ strongly from that resulting from aluminium-induced fragmentation of {sup 197}Au. The mean kinetic energies of the fragments are deduced from the experimental data. The importance of the new data to improve our understanding of the spallation mechanism and the relevance for the design of accelerator-driven sub-critical reactors is discussed. (authors)

  10. Moderator materials for the Spallation Neutron Source

    International Nuclear Information System (INIS)

    Charlton, L.A.

    1999-01-01

    The Spallation Neutron Source (SNS) is a neutron source providing intense neutron fluxes that will be used for performing a large variety of neutron scattering experiments. SNS is to be completed and start operation in 2005. Protons will be accelerated to 1 GeV, stored in an accumulator ring, and then injected into a neutron-producing target. After leaving the target (Hg in the ca/se of SNS), the neutrons are prepared for experiments by first using a moderator to impose energy and width requirements on the neutron pulse. One of the most important ingredients is the moderator material. Four materials that are commonly used and that were considered for use in SNS are liquid hydrogen (L-H 2 ), liquid water (L-H 2 O), liquid methane (L-CH 4 ), and solid methane (S-CH 4 ). The spectra (neutron current versus neutron energy) for these four materials are shown. As may be seen, at low neutron energies ( 4 , which produces up to four times as many neutrons in this energy range as L-H 2 . The problem with the material is the internal storage of energy that can be spontaneously and explosively released. At energies of just above 10 MeV, the most effective moderator material is L-CH 4 . Polymerization problems, however, preclude its use at high powers (again such as in SNS), where the buildup of undesirable materials becomes prohibitive. This is, however, an important energy range for neutron experiments. Preliminary consideration is being given to a composite moderator that contains two adjacent sections, one of L-H 2 and one of L-H 2 O, which produces a spectrum that is very similar to L-CH 4

  11. Accelerator and spallation target technologies for ADS applications

    International Nuclear Information System (INIS)

    2005-01-01

    The efficient and safe management of spent fuel produced during the operation of commercial nuclear power plants is an important issue. Worldwide, more than 250 000 tons of spent fuel from reactors currently operating will require disposal. These numbers account for only high-level radio-active waste generated by present-day power reactors. Nearly all issues related to risks to future generations arising from the long-term disposal of such spent nuclear fuel is attributable to only about 1% of its content. This 1% is made up primarily of plutonium, neptunium, americium and curium (called transuranic elements) and the long-lived isotopes of iodine and technetium. When transuranics are removed from discharged fuel destined for disposal, the toxic nature of the spent fuel drops below that of natural uranium ore (that which was originally mined for the nuclear fuel) within a period of several hundred years. This significantly reduces the burden on geological repositories and the problem of addressing the remaining long-term residues can thus be done in controlled environments having timescales of centuries rather than millennia. To address the disposal of transuranics, accelerator-driven systems (ADS), i.e. a sub-critical system driven by an accelerator to sustain the chain reaction, seem to have great potential for transuranic transmutation, though much R and D work is still required in order to demonstrate their desired capability as a whole system. This report describes the current status of accelerator and spallation target technologies and suggests technical issues that need to be resolved for ADS applications. It will be of particular interest to nuclear scientists involved in ADS development and in advanced fuel cycles in general. (author)

  12. Mitigation technologies for damage induced by pressure waves in high-power mercury spallation neutron sources (1). Material surface improvement

    International Nuclear Information System (INIS)

    Naoe, Takashi; Futakawa, Masatoshi; Wakui, Takashi; Kogawa, Hiroyuki; Shoubu, Takahisa; Takeuchi, Hirotsugu; Kawai, Masayoshi

    2008-01-01

    Liquid-mercury target systems for MW-class spallation neutron sources are being developed in the world. Proton beams will be used to induce the spallation reaction. At the moment the proton beam hits the target, pressure waves are generated in the mercury because of the abrupt heat deposition. The pressure waves interact with the target vessel leading to negative pressure that may cause cavitation along the vessel wall. Localized impacts by microjets and/or shock waves that are caused by cavitation bubble collapse impose pitting damage on the vessel wall. Bubble collapse behavior was observed by using a high-speed video camera, as well as simulated numerically. Localized impact due to cavitation bubble collapse was quantitatively estimated through comparison between numerical simulation and experiment. A novel surface treatment technique that consists of carburizing and nitriding processes was developed and the treatment condition was optimized to mitigate the pitting damage due to localized impacts. (author)

  13. Proton induced changes of the texturing degree of superconducting YBaCuO ceramics

    International Nuclear Information System (INIS)

    Kalanov, M.U.

    2004-01-01

    Full text: The aim of this work was to improve conducting properties of superconducting yttrium ceramics by means of proton-induced increase in the texturing degree. The object were single-phase (98 %), isotropic YBa 2 Cu 3 O 7-δ (δ ≅ 0.05) ceramic pellets of 12 mm in diameter and 0.6 mm of thickness, with the average grain size of 14 μm, the lattice parameters a r ≅ 3.822, b r ≅ 3.883 and c r ≅ 11.673 A, the density ∼ 5.1 g.cm -3 , the specific resistance ∼ 3 mΩ· cm in the normal state, had the superconducting T c ≅ 91 K. The samples were irradiated at the cyclotron U-150 of the INP AS RUz with 18 MeV-protons within the range of fluences 1014 - 10 15 cm -2 at the beam current of 20 nA and 300 K. The structure characteristics of samples were determined at the diffractometer DRON-UM1 (λ CuKα 1.54178 A). Electrophysical parameters were measured with the four-probe technique at the direct current of 10 mA. The texturing degree was determined by the formula F t = P t - P o /1 - P o , where P o and P t are the ratios of the (00L) reflection intensity sum to that of all (HKL) structure lines for isotropic and textured ceramics, respectively. The diffraction spectrum of the sample irradiated with the proton fluence of 2·10 14 cm -2 demonstrated a noticeable decrease in the {HKL} reflection intensities and simultaneous increase in those of {00L}. By this the value of ρ (100 K) decreased in 3 times, and the T c by 0.3 K, the superconducting transition broadened and the resistivity slope of the temperature dependence increased. Further growth of the {{00L} line intensities at elevated doses (4·10 14 † 8·10 14 cm -2 ) did not occur, yet the ρ (100 K) value rose fast, the T c dropped, and the character of conductivity changed from metallic to semiconducting. Such anomaly in the structure characteristics and superconducting properties of the irradiated YBa 2 Cu 3 O 7-δ ceramics can be explained by formation of the texture on the sample surface

  14. GRAIN-SCALE FAILURE IN THERMAL SPALLATION DRILLING

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, S C; Lomov, I; Roberts, J J

    2012-01-19

    Geothermal power promises clean, renewable, reliable and potentially widely-available energy, but is limited by high initial capital costs. New drilling technologies are required to make geothermal power financially competitive with other energy sources. One potential solution is offered by Thermal Spallation Drilling (TSD) - a novel drilling technique in which small particles (spalls) are released from the rock surface by rapid heating. While TSD has the potential to improve drilling rates of brittle granitic rocks, the coupled thermomechanical processes involved in TSD are poorly described, making system control and optimization difficult for this drilling technology. In this paper, we discuss results from a new modeling effort investigating thermal spallation drilling. In particular, we describe an explicit model that simulates the grain-scale mechanics of thermal spallation and use this model to examine existing theories concerning spalling mechanisms. We will report how borehole conditions influence spall production, and discuss implications for macro-scale models of drilling systems.

  15. Characterization of the radiation background at the Spallation Neutron Source

    International Nuclear Information System (INIS)

    DiJulio, Douglas D.; Cherkashyna, Nataliia; Scherzinger, Julius; Khaplanov, Anton; Pfeiffer, Dorothea; Cooper-Jensen, Carsten P.; Fissum, Kevin G.; Kanaki, Kalliopi; Kirstein, Oliver; Hall-Wilton, Richard J.; Bentley, Phillip M.; Ehlers, Georg; Gallmeier, Franz X.; Hornbach, Donald E.; Iverson, Erik B.; Newby, Robert J.

    2016-01-01

    We present a survey of the radiation background at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory, TN, USA during routine daily operation. A broad range of detectors was used to characterize primarily the neutron and photon fields throughout the facility. These include a WENDI-2 extended range dosimeter, a thermoscientific NRD, an Arktis 4 He detector, and a standard NaI photon detector. The information gathered from the detectors was used to map out the neutron dose rates throughout the facility and also the neutron dose rate and flux profiles of several different beamlines. The survey provides detailed information useful for developing future shielding concepts at spallation neutron sources, such as the European Spallation Source (ESS), currently under construction in Lund, Sweden. (paper)

  16. Future prospects of imaging at spallation neutron sources

    International Nuclear Information System (INIS)

    Strobl, M.

    2009-01-01

    The advent of state-of-the-art spallation neutron sources is a major step forward in efficient neutron production for most neutron scattering techniques. Although they provide lower time-averaged neutron flux than high flux reactor sources, advantage for different instrumental techniques can be derived from the pulsed time structure of the available flux, which can be translated into energy, respectively, wavelength resolution. Conventional neutron imaging on the other hand relies on an intense continuous beam flux and hence falls short in profiting from the new development. Nevertheless, some recently developed novel imaging techniques require and some can benefit from energy resolution. The impact of the emerging spallation sources on different imaging techniques has been investigated, ways to benefit will be identified (where possible) and prospects of future imaging instruments and possible options and layouts at a spallation neutron source will be discussed and outlined.

  17. Neutron scattering instrumentation for biology at spallation neutron sources

    Energy Technology Data Exchange (ETDEWEB)

    Pynn, R. [Los Alamos National Laboratory, NM (United States)

    1994-12-31

    Conventional wisdom holds that since biological entities are large, they must be studied with cold neutrons, a domain in which reactor sources of neutrons are often supposed to be pre-eminent. In fact, the current generation of pulsed spallation neutron sources, such as LANSCE at Los Alamos and ISIS in the United Kingdom, has demonstrated a capability for small angle scattering (SANS) - a typical cold- neutron application - that was not anticipated five years ago. Although no one has yet built a Laue diffractometer at a pulsed spallation source, calculations show that such an instrument would provide an exceptional capability for protein crystallography at one of the existing high-power spoliation sources. Even more exciting is the prospect of installing such spectrometers either at a next-generation, short-pulse spallation source or at a long-pulse spallation source. A recent Los Alamos study has shown that a one-megawatt, short-pulse source, which is an order of magnitude more powerful than LANSCE, could be built with today`s technology. In Europe, a preconceptual design study for a five-megawatt source is under way. Although such short-pulse sources are likely to be the wave of the future, they may not be necessary for some applications - such as Laue diffraction - which can be performed very well at a long-pulse spoliation source. Recently, it has been argued by Mezei that a facility that combines a short-pulse spallation source similar to LANSCE, with a one-megawatt, long-pulse spallation source would provide a cost-effective solution to the global shortage of neutrons for research. The basis for this assertion as well as the performance of some existing neutron spectrometers at short-pulse sources will be examined in this presentation.

  18. Neutron scattering instruments for the Spallation Neutron Source (SNS)

    International Nuclear Information System (INIS)

    Crawford, R.K.; Fornek, T.; Herwig, K.W.

    1998-01-01

    The Spallation Neutron Source (SNS) is a 1 MW pulsed spallation source for neutron scattering planned for construction at Oak Ridge National Laboratory. This facility is being designed as a 5-laboratory collaboration project. This paper addresses the proposed facility layout, the process for selection and construction of neutron scattering instruments at the SNS, the initial planning done on the basis of a reference set of ten instruments, and the plans for research and development (R and D) to support construction of the first ten instruments and to establish the infrastructure to support later development and construction of additional instruments

  19. The characterisation of Melanesian obsidian sources and artefacts using the proton induced gamma-ray emission (PIGME) technique

    International Nuclear Information System (INIS)

    Bird, J.R.; Ambrose, W.R.; Russell, L.H.; Scott, M.D.

    1981-09-01

    Proton induced gamma-ray emission (PIGME) has been used to determine F, Na and Al concentrations in obsidian from known locations in Melanesia and to relate artefacts from this region to such sources. The PIGME technique is a fast, non-destructive, and accurate method for determining these three elements with essentially no special sample preparation. The measuring technique is described and results are listed for sources, chiefly in the Papua New Guinea region. Their classification is discussed in terms of groups which are distinguishable by the PIGME method. Over 700 artefact results are listed; these show the occurrence of an additional group that is not geographically identified

  20. Mercury erosion experiments for spallation target system

    International Nuclear Information System (INIS)

    Kinoshita, Hidetaka; Kaminaga, Masanori; Haga, Katsuhiro; Hino, Ryutaro

    2003-01-01

    The Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) are promoting a plan to construct the spallation neutron source at the Tokai Research Establishment, JAERI, under the High-Intensity Proton Accelerator Project (J-PARC). A mercury circulation system has been designed so as to supply mercury to the target stably under the rated flow rate of 41 m 3 /hr. Then, it was necessary to confirm a mercury pump performance from the viewpoint of making the mercury circulation system feasible, and more, to investigate erosion rate under the mercury flow as well as an amount of mercury remained on the surface after drain from the viewpoints of mechanical strength relating to the lifetime and remote handling of mercury components. The mercury pump performance was tested under the mercury flow conditions by using an experimental gear pump, which had almost the same structure as a practical mercury pump to be expected in the mercury circulation system, and the erosion rates in a mercury pipeline as well as the amount of mercury remained on the surface were also investigated. The discharged flow rates of the experimental gear pump increased linearly with the rotation speed, so that the gear pump would work as the flow meter. Erosion rates obtained under the mercury velocity less than 1.6 m/s was found to be so small that decrease of pipeline wall thickness would be 390 μm after 30-year operation under the rated mercury velocity of 0.7 m/s. For the amount of remaining mercury on the pipeline, remaining rates of weight and volume were estimated at 50.7 g/m 2 and 3.74 Hg-cm 3 /m 2 , respectively. Applying these remaining rates of weight and volume to the mercury target, the remaining mercury was estimated at about 106.5 g and 7.9 cm 3 . Radioactivity of this remaining mercury volume was found to be three-order lower than that of the target casing. (author)

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

    International Nuclear Information System (INIS)

    Jacob, N.P. Jr.

    1975-07-01

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

  2. Some safety studies of the MEGAPIE spallation source target performed using computational fluid dynamics

    International Nuclear Information System (INIS)

    Smith, B.L.

    2011-01-01

    Such a target forms part of the evolutionary Accelerator-Driven System (ADS) concept in which neutrons are generated in an otherwise sub-critical core by spallation reactions resulting from bombardment by a proton beam. The international project MEGAPIE had the objective of demonstrating the feasibility of the spallation process for a particular target design under strict test conditions. The test was carried over a period of four months at the end of 2006 at the SINQ facility of the Paul Scherrer Institute in Switzerland. The design studies carried out for the MEGAPIE target prior to irradiation using Computational Fluid Dynamics (CFD) resulted in an optimum flow configuration being defined for the coolant circulation. Simultaneously, stresses in the structural components were examined using Finite Element Method (FEM) techniques. To this purpose, an interface program was written which enabled different specialist groups to carry out the thermal hydraulics and structural mechanics analyses within the project with fully consistent model data. Results for steady-state operation of the target show that the critical lower target components are adequately cooled, and that stresses and displacements are well within tolerances. Transient analyses were also performed to demonstrate the robustness of the design in the event of abnormal operation, including pump failure and burn-through of the target casing by the proton beam. In the latter case, the CFD analyses complemented and extended full-scale tests. (author)

  3. Spallation radiation damage and dosimetry for accelerator transmutation of waste applications

    International Nuclear Information System (INIS)

    Wechsler, M.S.; Lin, C.

    1993-01-01

    Proposals are currently being made for systems to treat radioactive waste based on the use of accelerator-driven neutron sources. A linear proton accelerator with energies as high as 1600 MeV and currents up to 250 ma are anticipated for the driver. The neutron fluxes may reach up to 10 20 neutrons/m 2 s as generated by the spallation reactions that occur when the protons strike target materials. Calculations are described to determine radiation fluxes and flux spectra inherent in such systems and to estimate likely radiation effects on system components. The calculations use LAHET, a Monte Carlo high-energy transport code, and MCNP, a generalized-geometry, coupled neutron-photon Monte Carlo transport code. Cross sections for displacement and helium production are presented for spallation neutrons of energies from 21 MeV to 1600 MeV for Inconel 718 (Ni plus 18.5, 18.5, 5.1, and 3 wt % of Cr, Fe, Nb, and Mo, respectively), an alloy that is used for the proton beam entry window in several accelerators. In addition, results for this alloy are presented for the primary knocked-on atom (PKA) spectrum and the transmutation yield for 1600 MeV incident neutrons

  4. Some safety studies of the MEGAPIE spallation source target performed using computational fluid dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Smith, B.L., E-mail: brian.smith@psi.ch [Paul Scherrer Institute, OHSA/C08, 5232 Villigen PSI (Switzerland)

    2011-07-01

    Such a target forms part of the evolutionary Accelerator-Driven System (ADS) concept in which neutrons are generated in an otherwise sub-critical core by spallation reactions resulting from bombardment by a proton beam. The international project MEGAPIE had the objective of demonstrating the feasibility of the spallation process for a particular target design under strict test conditions. The test was carried over a period of four months at the end of 2006 at the SINQ facility of the Paul Scherrer Institute in Switzerland. The design studies carried out for the MEGAPIE target prior to irradiation using Computational Fluid Dynamics (CFD) resulted in an optimum flow configuration being defined for the coolant circulation. Simultaneously, stresses in the structural components were examined using Finite Element Method (FEM) techniques. To this purpose, an interface program was written which enabled different specialist groups to carry out the thermal hydraulics and structural mechanics analyses within the project with fully consistent model data. Results for steady-state operation of the target show that the critical lower target components are adequately cooled, and that stresses and displacements are well within tolerances. Transient analyses were also performed to demonstrate the robustness of the design in the event of abnormal operation, including pump failure and burn-through of the target casing by the proton beam. In the latter case, the CFD analyses complemented and extended full-scale tests. (author)

  5. Target designs for the Brookhaven National Laboratory 5-MW pulsed spallation neutron source

    International Nuclear Information System (INIS)

    Ludewig, H.; Todosow, M.; Powell, J.R.

    1996-01-01

    A feasibility study of a compact high power density target for a spallation neutron source was under-taken. The target arrangement consists primarily of heavy metal, with appropriate cooling passages. A high intensity proton beam of intermediate energy is directed at the target, where it interacts with the heavy metal nuclei. The subsequent spallation reactions produce several neutrons per proton resulting in an intense neutron source. The proton beam is assumed to havean energy of 5 MW, and to be cyclic with a repetition rate of 10Hz and 50Hz. The study was divided into two broad sections. First, an analysis of preliminary target designs was undertaken to ensure the overall feasibility of the concepts involved in the design and eventual construction of such a high power density target. Second, two proposed target designs, based on the first set of analyses, are investigated in more detail. Special care is taken to ensure that the neutron fluxes in the moderator are at the desired level no material compatibility problems exist,and the target is able to operate in a reliable and safe manner. Several target materials, coolant types, and target arrangements are investigated in the first section. The second section concentrates on a single target material and geometric arrangement. However, several structural material choices continue to be investigated with the aim of minimizing the effects of structural heating, and associated thermally induced stresses. In the final section the conclusions of this preliminary study are summarized

  6. Radiation effects in structural materials of spallation targets

    Science.gov (United States)

    Jung, P.

    2002-02-01

    Effects of radiation damage by protons and neutrons in structural materials of spallation neutron sources are reviewed. Effects of atomic displacements, defect mobility and transmutation products, especially hydrogen and helium, on physical and mechanical properties are discussed. The most promising candidate materials (austenitic stainless steels, ferritic/martensitic steels and refractory alloys) are compared, and needed investigations are identified.

  7. MEGAPIE-TEST: A European Project on Spallation Target Testing

    International Nuclear Information System (INIS)

    Knebel, Joachim U.; Klein, Jean-Christophe; Gorse, Dominique; Agostini, Pietro; Groeschel, Friedrich; Kupschus, Peter; Kirchner, Thomas; Vogt, Jean-Bernard

    2002-01-01

    Within the Euratom 5. Framework Programme (5FP) the European Commission is funding the MEGAPIE-TEST Project (Megawatt Pilot Experiment - Testing) over a period of three years, starting in September 2001. The project is combining the efforts of 8 main associations. MEGAPIE is a liquid metal spallation target of 1 MW of beam power. The main results of the MEGAPIE-TEST project will be: Development and comprehensive testing of a liquid metal spallation target both under beam-off and beam-on conditions, and the set up of a handbook on the design of a neutron spallation source in general. The operation of MEGAPIE within the accelerator complex SINQ at Paul Scherrer Institute (PSI), Switzerland, is envisaged in 2004. MEGAPIE is a first decisive step to realize a liquid metal spallation target in Europe. This report is giving an overview of the MEGAPIE-TEST Project, the overall work plan, and preliminary results from the design support and validation, which form an important basis for the project. (authors)

  8. Analytic model of heat deposition in spallation neutron target

    International Nuclear Information System (INIS)

    Findlay, D.J.S.

    2015-01-01

    A simple analytic model for estimating deposition of heat in a spallation neutron target is presented—a model that can readily be realised in an unambitious spreadsheet. The model is based on simple representations of the principal underlying physical processes, and is intended largely as a ‘sanity check’ on results from Monte Carlo codes such as FLUKA or MCNPX.

  9. Analytic model of heat deposition in spallation neutron target

    Energy Technology Data Exchange (ETDEWEB)

    Findlay, D.J.S.

    2015-12-11

    A simple analytic model for estimating deposition of heat in a spallation neutron target is presented—a model that can readily be realised in an unambitious spreadsheet. The model is based on simple representations of the principal underlying physical processes, and is intended largely as a ‘sanity check’ on results from Monte Carlo codes such as FLUKA or MCNPX.

  10. Towards the construction of the European spallation source–The ...

    Indian Academy of Sciences (India)

    The possible realization of the European spallation source has been a long and winding story. However, thanks to the conjunction of a number of events it now looks highly probable that in 2008 there will indeed be a decision on the site and on a funding partnership of European countries who will together build and ...

  11. Observation of galactic cosmic ray spallation events from the SoHO mission 20-Year operation of LASCO

    Science.gov (United States)

    Koutchmy, S.; Tavabi, E.; Urtado, O.

    2018-05-01

    A shower of secondary Cosmic Ray (CR) particles is produced at high altitudes in the Earth's atmosphere, so the primordial Galactic Cosmic Rays (GCRs) are never directly measured outside the Earth magnetosphere and atmosphere. They approach the Earth and other planets in the complex pattern of rigidity's dependence, generally excluded by the magnetosphere. GCRs revealed by images of single nuclear reactions also called spallation events are described here. Such an event was seen on Nov. 29, 2015 using a unique LASCO C3 space coronagraph routine image taken during the Solar and Heliospheric Observatory (SoHO) mission observing uninterruptedly at the Lagrangian L1 point. The spallation signature of a GCR identified well outside the Earth's magnetosphere is obtained for the 1st time. The resulting image includes different diverging linear "tracks" of varying intensity, leading to a single pixel; this frame identifies the site on the silicon CCD chip of the coronagraph camera. There was no solar flare reported at that time, nor Coronal Mass Ejection (CME) and no evidence of optical debris around the spacecraft. More examples of smaller CR events have been discovered through the 20 years of continuous observations from SoHO. This is the first spallation event from a CR, recorded outside the Earth's magnetosphere. We evaluate the probable energy of these events suggesting a plausible galactic source.

  12. The RADEX facility as a tool for studies of radiation damage under proton and spallation neutron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Koptelov, E.A.; Lebedev, S.G.; Matveev, V.A.; Sobolevsky, N.M. [Institute for Nuclear Research of Russian Academy of Sciences, Moscow (Russian Federation); Strebkov, Yu.S.; Subbotin, A.V. [Research and Development Institute of Power Engineering, Moscow (Russian Federation)

    2001-03-01

    We present results of numerical modeling for processes of primary protons and spallation neutrons interactions with structural materials at the RADiation EXperiment facility of the Neutron Complex. The installation has a vertical irradiation channel inside the beam stop for horizontally incident protons with energies up to 600 MeV of the Moscow Meson Factory of the INR (Institute for Nuclear Research) RAS (Russian Academy of Science). The calculations are based on a set of computer codes SHIELD and RADDAM, which were developed in the INR RAS and give data on point defect generation by irradiation, rate of accumulation of H and He atoms produced in nuclear reactions, energetic spectra of primary knocked-off atoms in collision displacements, temperature of samples under irradiation. Different positions of the channel, which are available by rotation of a target relatively the vertical axis for angles 0, 60, 120 and 180 degrees to the proton beam direction, are considered. Changes of irradiation damage parameters due to various inputs of primary protons and spallation neutrons at different target orientations are demonstrated. It is shown also that the spallation neutron facility RADEX may provide with perspective experimental possibilities for modeling of irradiation conditions for fusion reactors ITER and DEMO. (author)

  13. Study of steady-state heat transfer with various large beam intensities in ADS windowless spallation target

    International Nuclear Information System (INIS)

    Liu, Jie; Gao, Lei; Tong, Jian-fei; Mehmood, Irfan; Lu, Wen-qiang

    2015-01-01

    Thermal hydraulics of spallation target, which is regarded as the ‘heart’ of the accelerator driven system (ADS), is very complicated due to the flow of the heavy liquid metal, spallation reaction and the coupling. In this paper, the steady-state temperature distribution, based on the flow pattern and the heat deposition, in the windowless spallation target with various large beam intensities from 10 mA to 40 mA is obtained to be in line with the development of ADS in China. The results show that the shape of temperature distribution is the same as broken wing of the butterfly but the temperature gradient and the maximum temperature vary in proportion with beam intensity. The variation of temperature gradient in different zones is also used to figure out the effect of large beam intensity. It has been found that large radial and axial temperature gradient leads to large temperature gradient on the wall. This may cause extremely large thermal stresses which leads to structural material damage. The results may be applied to the future design and optimization of ADS in China. - Highlights: • Shape of temperature distribution is the same but temperature gradient and maximum temperature vary with intensity. • The variation of temperature gradient in different zones reveals the effect of large beam intensity. • Large radial and axial temperature gradient leads to large temperature gradient on the wall

  14. CFD studies on thermal hydraulics of spallation targets

    International Nuclear Information System (INIS)

    Tak, N.I.; Batta, A.; Cheng, X.

    2005-01-01

    Full text of publication follows: Due to the fast advances in computer hardware as well as software in recent years, more and more interests have been aroused to use computational fluid dynamics (CFD) technology in nuclear engineering and designs. During recent many years, Forschungszentrum Karlsruhe (FZK) has been actively involved in the thermal hydraulic analysis and design of spallation targets. To understand the thermal hydraulic behaviors of spallation targets very detailed simulations are necessary because of their complex geometries, complicated boundary conditions such as spallation heat distributions, and very strict design limits. A CFD simulation is believed to be the best for this purpose even though the validation of CFD codes are not perfectly completed yet in specific topics like liquid metal heat transfer. The research activities on three spallation targets (i.e., MEGAPIE, TRADE, and XADS targets) are currently very active in Europe in order to consolidate the European ADS road-map. In the thermal hydraulics point of view, two kinds of the research activities, i.e., (1) numerical design and (2) experimental work, are required to achieve the objectives of these targets. It should be noted that CFD studies play important role on both kinds of two activities. A preliminary design of a target can be achieved by sophisticated CFD analysis and pre-and-post analyses of an experimental work using a CFD code help the design of the test section of the experiment as well as the analysis of the experimental results. The present paper gives an overview about the recent CFD studies relating to thermal hydraulics of the spallation targets recently involved in FZK. It covers numerical design studies as well as CFD studies to support experimental works. The CFX code has been adopted for the studies. Main recent results for the selected examples performed by FZK are presented and discussed with their specific lessons learned. (authors)

  15. Measurement of proton induced thick target γ-ray yields on B, N, Na, Al and Si from 2.5 to 4.1 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Chiari, M., E-mail: chiari@fi.infn.it [INFN-Florence and Department of Physics and Astronomy, University of Florence, via G. Sansone 1, 50019 Sesto Fiorentino (Italy); Ferraccioli, G.; Melon, B.; Nannini, A.; Perego, A.; Salvestrini, L. [INFN-Florence and Department of Physics and Astronomy, University of Florence, via G. Sansone 1, 50019 Sesto Fiorentino (Italy); Lagoyannis, A.; Preketes-Sigalas, K. [Tandem Accelerator Laboratory, Institute of Nuclear and Particle Physics, NCSR “Demokritos”, 153.10 Aghia Paraskevi, Athens (Greece)

    2016-01-01

    Thick target yields for proton induced γ-ray emission (PIGE) on low-Z nuclei, namely B, N, Na, Al and Si, were measured for proton energies from 2.5 to 4.1 MeV and emission angles of 0°, 45° and 90°, at the 3 MV Tandetron laboratory of INFN-LABEC in Florence. The studied reactions were: {sup 10}B(p,α′γ){sup 7}Be (E{sub γ} = 429 keV), {sup 10}B(p,p′γ){sup 10}B (E{sub γ} = 718 keV) and {sup 11}B(p,p′γ){sup 11}B (E{sub γ} = 2125 keV) for boron; {sup 14}N(p,p′γ){sup 14}N (E{sub γ} = 2313 keV) for nitrogen; {sup 23}Na(p,p′γ){sup 23}Na (E{sub γ} = 441 and 1636 keV) and {sup 23}Na(p,α′γ){sup 20}Ne (E{sub γ} = 1634 keV) for sodium; {sup 27}Al(p,p′γ){sup 27}Al (E{sub γ} = 844 and 1014 keV) and {sup 27}Al(p,α′γ){sup 24}Mg (E{sub γ} = 1369 keV) for aluminum; {sup 28}Si(p,p′γ){sup 28}Si (E{sub γ} = 1779 keV) and {sup 29}Si(p,p′γ){sup 29}Si (E{sub γ} = 1273 keV) for silicon. The PIGE thick target yields have been measured with an overall uncertainty typically better than 10%. The use of the measured thick target yield to benchmark and validate experimental cross sections available in the literature is demonstrated.

  16. Proceedings of the specialists' meeting on physics and engineering of fission and spallation, 1989

    International Nuclear Information System (INIS)

    Nakagome, Yoshihiro

    1990-07-01

    The third meeting was held on August 1, and the fourth meeting was held on December 12, 1989. The reports of the international conferences on 50 years research on nuclear fission in Germany and USA, and the reports on the nuclear data of fission-produced nuclei for evaluating reactor decay heat, the atomic mass formula considering proton-neutron interaction and unstable nuclei, research on short life fission fragments by on-line isotope separation process, the reactor physics on waste annihilation disposal and fuel breeding with an accelerator, the double differential cross section of back neutrons in nuclear spallation reaction, measurement of fission cross section and fission neutron spectra with fast neutrons, U-235 fission spectra by unfolding activation foil data and production mechanisms of intermediate mass fragments from hot nuclei-emission of complex and fission fragments for 84 Kr+ 27 Al at 10.6 MeV/u were made. (K.I.)

  17. Proton Induced X-Rays Emission (PIXE) and Atomic Absorption Spectrometry (AAS) applied in the environmental sample analysis

    International Nuclear Information System (INIS)

    Popescu, Ion V.; Iordan, M.; Stihi, C.; Bancuta, A.; Dima, G.; Busuioc, G.; Ciupina, V.; Belc, M.; Badica, T.

    2003-01-01

    The aim of this work is to determine the elemental composition of tree leaves using Proton-Induced X-Rays Emission (PIXE) and Atomic Absorption Spectrophotometry (AAS) methods. By PIXE Spectrometry we identified and determined the concentration of S, Cl, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu Zn, As, Br, Sr and by AAS method the concentration of elements: Cr, Mn, Fe, Co, Cu, Zn, Se, Cd. Pb was identified in only 2 samples from 29. For tree leave samples collected at a large distance to the polluting source the Sr concentration decreased and the Mg, Ca, Se, Zn and Fe concentrations increased. Also, we can observe a small affinity of these leaves for the environmental Pb which was detected for two samples at a small distance to polluting source. (authors)

  18. Geophysical applicability of aerosol size distribution measurements using cascade impactors and proton induced X-ray emission

    International Nuclear Information System (INIS)

    Van Grieken, R.E.; Johansson, T.B.; Akselsson, K.R.; Winchester, J.W.; Nelson, J.W.; Chapman, K.R.

    1976-01-01

    Proton Induced X-ray Emission, (PIXE), is capable of high precision analysis for trace element components of aerosol particle size fractions sampled by cascade impactor. A statistical evaluation of data quality has been carried out in order to distinguish between analytical uncertainties in the PIXE procedure, errors caused by cascade impactor performance and by other factors in the sampling procedure, and geophysical causes of differences in composition and particle size distributions of the elements in aerosols. Replicate analyses and simultaneous samplings taken in north Florida and St. Louis have been used for the data evaluation. In addition to the analytical error the sampling procedure contributes an error of approximately 10% to be added quadratically. The resulting precision is sufficient to evaluate the data in geophysical terms. This is illustrated by means of sample sets taken simultaneously in an urban, forest and coastal environment of the same region. (author)

  19. New insights gained on mechanisms of low-energy proton-induced SEUs by minimizing energy straggle

    International Nuclear Information System (INIS)

    Dodds, Nathaniel Anson; Dodd, Paul E.; Shaneyfelt, Marty R.; Sexton, Frederick W.; Martinez, Marino J.; Black, Jeffrey D.; Marshall, P. W.; Reed, R. A.; McCurdy, M. W.; Weller, R. A.; Pellish, J. A.; Rodbell, K. P.; Gordon, M. S.

    2015-01-01

    In this study, we present low-energy proton single-event upset (SEU) data on a 65 nm SOI SRAM whose substrate has been completely removed. Since the protons only had to penetrate a very thin buried oxide layer, these measurements were affected by far less energy loss, energy straggle, flux attrition, and angular scattering than previous datasets. The minimization of these common sources of experimental interference allows more direct interpretation of the data and deeper insight into SEU mechanisms. The results show a strong angular dependence, demonstrate that energy straggle, flux attrition, and angular scattering affect the measured SEU cross sections, and prove that proton direct ionization is the dominant mechanism for low-energy proton-induced SEUs in these circuits

  20. Determination of total fluorine in five coal reference materials by proton-induced gamma-ray emission spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Roelandts, I.; Robaye, G.; Delbrouck-Habaru, J.M.; Weber, G. [University of Liege, Sart (Belgium). Dept. of Geology, Petrology and Geochemistry

    1996-03-01

    The direct non-destructive proton-induced gamma-ray emission (PIGE) technique with a germanium detector was applied to the determination of total fluorine concentration in five coal reference materials (BCR 30, NIST 1632b, NIST 1635, SARM 20 and USGS CLB-1). Duplicate analyses were made from five randomly selected bottles of each coal. Individual data are presented and some problems (calibration, proton stopping power, effects of sample heating by the proton beam, background estimation) which were encountered during this study are discussed. Sensitivity and reproducibility of the determinations, and homogeneity of the coal samples with respect to fluorine contents by analysis of variance were investigated. The present data are also compared with the few published values for these reference samples, including other PIGE data. The use of synthetic standards and spiked samples in the present study suggested that the PIGE method was more accurate than other techniques.

  1. Proton induced nuclide production cross section by HETC-3STEP/FRG-R

    Energy Technology Data Exchange (ETDEWEB)

    Shigyo, Nobuhiro; Ishibashi, Kenji [Kyushu Univ., Fukuoka (Japan); Yoshizawa, Nobuaki; Takada, Hiroshi

    1998-03-01

    High Energy Transport Code (HETC) based on the intranuclear-cascade-evaporation model is modified to calculate the fragmentation cross section. The exciton model is adopted for improvement of backward nucleon-emission cross section for low-energy nucleon-incident events. The level density parameter depending on the excitation energy is taken in the evaporation process. The fragmentation reaction is incorporated into HETC as a subroutine set by the use of the systematics of the reaction. The modified HETC (HETC-3STEP/FRG-R) reproduces experimental fragment yields to a reasonable degree. (author)

  2. Neutrino physics at the spallation neutron source. Pt. 2

    International Nuclear Information System (INIS)

    Gabriel, T.A.; Lillie, R.A.; Bishop, B.L.; Wilczynski, J.; Zeitnitz, B.

    1981-06-01

    The shielding and detector analysis associated with a contemplated low energy (approx. equal to10 to 50 MeV) neutrino experiment at a spallation neutron source are presented and discussed. This analysis includes neutrino production and interaction rates, time dependence of the neutrino pulse, shielding considerations for neutrons coming directly from the spallation source and those which are scattered from other experimental areas, shielding considerations for galactic sources especially muons and finally detector responses to neutrino and background radiations. In general for a 1 mA (200 ns/pulse, 100 Hz), 1.1 GeV proton beam incident on a lead target surrounded by a moderator system, approximately 8 m of iron are required to reduce the background so that the event rate in the detector systems is approx. [de

  3. Overcoming High Energy Backgrounds at Pulsed Spallation Sources

    CERN Document Server

    Cherkashyna, Nataliia; DiJulio, Douglas D.; Khaplanov, Anton; Pfeiffer, Dorothea; Scherzinger, Julius; Cooper-Jensen, Carsten P.; Fissum, Kevin G.; Ansell, Stuart; Iverson, Erik B.; Ehlers, Georg; Gallmeier, Franz X.; Panzner, Tobias; Rantsiou, Emmanouela; Kanaki, Kalliopi; Filges, Uwe; Kittelmann, Thomas; Extegarai, Maddi; Santoro, Valentina; Kirstein, Oliver; Bentley, Phillip M.

    2015-01-01

    Instrument backgrounds at neutron scattering facilities directly affect the quality and the efficiency of the scientific measurements that users perform. Part of the background at pulsed spallation neutron sources is caused by, and time-correlated with, the emission of high energy particles when the proton beam strikes the spallation target. This prompt pulse ultimately produces a signal, which can be highly problematic for a subset of instruments and measurements due to the time-correlated properties, and different to that from reactor sources. Measurements of this background have been made at both SNS (ORNL, Oak Ridge, TN, USA) and SINQ (PSI, Villigen, Switzerland). The background levels were generally found to be low compared to natural background. However, very low intensities of high-energy particles have been found to be detrimental to instrument performance in some conditions. Given that instrument performance is typically characterised by S/N, improvements in backgrounds can both improve instrument pe...

  4. Accumulator ring lattice for the national spallation neutron source

    International Nuclear Information System (INIS)

    Gardner, C.J.; Lee, Y.Y.; Luccio, A.U.

    1997-01-01

    The Accumulator Ring for the proposed National Spallation Neutron Source (NSNS) is to accept a 1.03 millisecond beam pulse from a 1 GeV Proton Linac at a repetition rate of 60 Hz. For each beam pulse, 10 14 protons are to be accumulated via charge-exchange injection. A 295 nanosecond gap in the beam, maintained by an rf system, will allow for extraction to an external target for the production of neutrons by spallation. This paper describes the four-fold symmetric lattice that has been chosen for the ring. The lattice contains four long dispersion-free straight sections to accomodate injection, extraction, rf cavities, and beam scraping respectively. The four-fold symmetry allows for easy adjustment of the tunes and flexibility in the placement of correction elements, and ensures that potentially dangerous betatron structure resonances are avoided

  5. Advanced spallation neutron sources for condensed matter research

    International Nuclear Information System (INIS)

    Lovesey, S.W.; Stirling, G.C.

    1984-03-01

    Advanced spallation neutron sources afford significant advantages over existing high flux reactors. The effective flux is much greater than that currently available with reactor sources. A ten-fold increase in neutron flux will be a major benefit to a wide range of condensed matter studies, and it will realise important experiments that are marginal at reactor sources. Moreover, the high intensity of epithermal neutrons open new vistas in studies of electronic states and molecular vibrations. (author)

  6. Irradiation facilities at the spallation neutron source SINQ

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, E.; Ledermann, J.; Aebersold, H.; Kuehne, G.; Kohlik, K. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    Four independent experiments for sample irradiation are under construction and in preparation for operational tests at the spallation source SINQ. Three of them are located inside a thermal beam port with end positions inside or near the moderator tank. The other experiment will be established at the end position of a super mirror lined neutron guide for applications with cold neutrons. (author) 3 figs., 1 tab., 6 refs.

  7. New scientific horizons with pulsed spallation neutron sources

    International Nuclear Information System (INIS)

    Carlile, C.J.; Finney, J.L.

    1991-01-01

    Pulsed spallation sources are not just another way of producing neutrons: the time structure of the neutron pulse has consequences which allow new scientific areas to be investigated and traditional areas to be explored afresh. In addition to the high epithermal neutron component traditionally associated with pulsed sources the recent development of cold neutron techniques at ISIS illustrates that very high energy and momentum resolutions can be achieved on pulsed sources over a surprisingly wide range. (orig.)

  8. Neutronic moderator design for the Spallation Neutron Source (SNS)

    International Nuclear Information System (INIS)

    Charlton, L.A.; Barnes, J.M.; Johnson, J.O.; Gabriel, T.A.

    1998-01-01

    Neutronics analyses are now in progress to support the initial selection of moderator design parameters for the Spallation Neutron Source (SNS). The results of the initial optimization studies involving moderator poison plate location, moderator position, and premoderator performance for the target system are presented in this paper. Also presented is an initial study of the use of a composite moderator to produce a liquid methane like spectrum

  9. Integral measurements of neutron production in spallation targets

    International Nuclear Information System (INIS)

    Frehaut, J.; Deneuville, D.; Ledoux, X.; Lochard, J.P.; Longuet, J.L.; Petibon, E.; Alrick, K.; Bownan, D.; Cverna, F.; King, N.S.P.; Morgan, G.L.; Greene, G.; Hanson, A.; Snead, L.; Thompson, R.; Ward, T.

    1998-01-01

    Measurements of neutron production for thick iron, tungsten and lead targets of different diameter prototypic for spallation systems have been made at SATURNE in an incident proton energy range from 400 MeV to 2 GeV. TIERCE code system calculations are in good agreement with experiment for iron and large diameter tungsten and lead targets. They overestimate the measured neutron production for tungsten and lead targets for diameter ≤20 cm. (author)

  10. The BLAIRR Irradiation Facility Hybrid Spallation Target Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Simos N.; Hanson A.; Brown, D.; Elbakhshawn, M.

    2016-04-11

    BLAIRR STUDY STATUS OVERVIEW Beamline Complex Evaluation/Assessment and Adaptation to the Goals Facility Radiological Constraints ? Large scale analyses of conventional facility and integrated shield (concrete, soil)Target Optimization and Design: Beam-target interaction optimization Hadronic interaction and energy deposition limitations Single phase and Hybrid target concepts Irradiation Damage Thermo-mechanical considerations Spallation neutron fluence optimization for (a) fast neutron irradiation damage (b) moderator/reflector studies, (c) NTOF potential and optimization (d) mono-energetic neutron beam

  11. Status of spallation neutron source program in High Intensity Proton Accelerator Project

    International Nuclear Information System (INIS)

    Oyama, Yukio

    2001-01-01

    Japan Atomic Energy Research Institute and High Energy Accelerator Organization are jointly designing a 1 MW spallation neutron source as one of the research facilities planned in the High Intensity Proton Accelerator Project. The spallation neutron source is driven by 3 GeV proton beam with a mercury target and liquid hydrogen moderators. The present status of design for these spallation source and relevant facility is overviewed. (author)

  12. Rationale for a spallation neutron source target system test facility at the 1-MW Long-Pulse Spallation Source

    International Nuclear Information System (INIS)

    Sommer, W.F.

    1995-12-01

    The conceptual design study for a 1-MW Long-Pulse Spallation Source at the Los Alamos Neutron Science Center has shown the feasibility of including a spallation neutron test facility at a relatively low cost. This document presents a rationale for developing such a test bed. Currently, neutron scattering facilities operate at a maximum power of 0.2 MW. Proposed new designs call for power levels as high as 10 MW, and future transmutation activities may require as much as 200 MW. A test bed will allow assessment of target neutronics; thermal hydraulics; remote handling; mechanical structure; corrosion in aqueous, non-aqueous, liquid metal, and molten salt systems; thermal shock on systems and system components; and materials for target systems. Reliable data in these areas are crucial to the safe and reliable operation of new high-power facilities. These tests will provide data useful not only to spallation neutron sources proposed or under development, but also to other projects in accelerator-driven transmutation technologies such as the production of tritium

  13. Proton-induced lithium destruction cross-section and its astrophysical implications

    CERN Document Server

    Pizzone, R G; Musumarra, A; Pellegrini, M G; Romano, S; Tumino, A; Pizzone, R G; Spitaleri, C; Lattuada, M; Musumarra, A; Pellegriti, M G; Romano, S; Tumino, A; Pizzone, R G; Lattuada, M; Cherubini, S; Castellani, V; Deflinnocenti, S; Imperio, A

    2003-01-01

    Knowledge of the primordial nucleosynthesis offers a powerful tool to retrieve information on the baryon density of the Universe. In this context lithium isotopes play a crucial role and in particular we stress how important the bare nucleus cross-section for the sup 7 Li(p,alpha) sup 4 He reaction is. Recent application of the Trojan Horse Method led to an indirect measurement of that cross-section. In the present paper its astrophysical implications are examined in the case of the Solar lithium problem and of the primordial nucleosynthesis. (authors)

  14. Proton-induced lithium destruction cross-section and its astrophysical implications

    International Nuclear Information System (INIS)

    Pizzone, R.G.; Spitaleri, C.; Musumarra, A.; Pellegrini, M.G.; Romano, S.; Tumino, A.; Pizzone, R.G.; Spitaleri, C.; Lattuada, M.; Musumarra, A.; Pellegriti, M.G.; Romano, S.; Tumino, A.; Pizzone, R.G.; Lattuada, M.; Cherubini, S.; Castellani, V.; Defl'Innocenti, S.; Imperio, A.

    2003-01-01

    Knowledge of the primordial nucleosynthesis offers a powerful tool to retrieve information on the baryon density of the Universe. In this context lithium isotopes play a crucial role and in particular we stress how important the bare nucleus cross-section for the 7 Li(p,α) 4 He reaction is. Recent application of the Trojan Horse Method led to an indirect measurement of that cross-section. In the present paper its astrophysical implications are examined in the case of the Solar lithium problem and of the primordial nucleosynthesis. (authors)

  15. Results of the Nonelastic Reaction Code Brieff for Nuclear Data

    International Nuclear Information System (INIS)

    Duarte, H.

    2009-01-01

    We present recent changes in our nonelastic reaction code BRIEFF and especially in the fast stage of reaction described by the intranuclear cascade (INC) code BRIC. Distributions and excitation functions of residual nuclei production cross sections are shown for proton-induced reaction on target nuclei. Slight improvements are seen in the proton-induced reaction on light nuclei with a closed shell when the energy levels are taken into account in the INC stage. On the other hand, fission gives poor results in the current version. To compare to other nuclear models and LA150 libraries, BRIEFF has been incorporated into MCNPX 2.5.0. Examples of neutron production from thick target irradiation by proton beams between 30 and 350 MeV are presented. Except for some discrepancies, a good agreement with data is obtained on average. (authors)

  16. Proton-induced fission cross sections on "2"0"8Pb at high kinetic energies

    International Nuclear Information System (INIS)

    Rodriguez-Sanchez, J.L.; Benlliure, J.; Paradela, C.; Ayyad, Y.; Alvarez-Pol, H.; Cortina-Gil, D.; Pietras, B.; Ramos, D.; Vargas, J.; Taieb, J.; Chatillon, A.; Belier, G.; Boutoux, G.; Gorbinet, T.; Laurent, B.; Martin, J.F.; Pellereau, E.; Casarejos, E.; Rodriguez-Tajes, C.

    2014-01-01

    Total fission cross sections of "2"0"8Pb induced by protons have been determined at 370 A, 500 A, and 650 A MeV. The experiment was performed at GSI Darmstadt where the combined use of the inverse kinematics technique with an efficient detection setup allowed us to determine these cross sections with an uncertainty below 6%. This result was achieved by an accurate beam selection and registration of both fission fragments in coincidence which were also clearly distinguished from other reaction channels. These data solve existing discrepancies between previous measurements, providing new values for the Prokofiev systematics. The data also allow us to investigate the fission process at high excitation energies and small deformations. In particular, some fundamental questions about fission dynamics have been addressed, which are related to dissipative and transient time effects. (authors)

  17. Proton induced nucleon knockout from 40Ca in the Dirac impulse approximation

    International Nuclear Information System (INIS)

    Maxwell, O.V.; Cooper, E.D.

    1989-12-01

    The (p,2p) reaction on 40 Ca at incident proton energies of 200 and 300 MeV is examined within a Dirac distorted wave impulse approximation. The relativistic Love-Franey t-matrix is evaluated at the nucleon-nucleon laboratory energy (as defined within the plane wave approximation), rather than the nucleon-nucleus laboratory energy. Particular attention is paid to the sensitivity of the calculated cross sections and analyzing powers to the properties of the bound states employed. It is found that the analyzing powers depend very little on the bound state properties, while the cross sections depend significantly only on the rms radii of the bound state wave functions. A major success of the model is its ability to fit the cross section data over a particular range of momentum transfers at both 200 and 300 MeV with the same bound state potential. Outside this momentum transfer range, the predicted cross sections are too low. The calculated analyzing powers agree well with the data at 200 MeV, but disagree with the data at 300 MeV. Values for the rms radii of the 1D 3/2 and 1D 5/2 states in 40 Ca are derived from the requirement that the peak positions of the calculated cross sections at 300 MeV agree with the empirical peak positions. Some preliminary results are also reported for neutron knockout from 40 Ca at 150 MeV

  18. Activation of 45-MeV proton irradiation and proton-induced neutron irradiation in polymers

    International Nuclear Information System (INIS)

    Ra, Se-Jin; Kim, Kye-Ryung; Jung, Myung-Hwan; Yang, Tae-Keon

    2010-01-01

    During beam irradiation experiments with more than a few MeV energetic protons, the sample activation problem can be very severe because it causes many kinds of additional problems for the post-processing of the samples, such as time loss, inconvenience of sample handling, personal radiation safety, etc. The most serious problem is that immediate treatment of the sample is impossible in some experiments, such as nano-particle synthesizing. To solve these problems, we studied why the samples are activated and how the level of the activation can be reduced. It is known that the main reasons of activation are nuclear reactions with elements of the target material by primary protons and secondary produced neutrons. Even though the irradiation conditions are same, the level of the activation can be different depending on the target materials. For the nanoparticle synthesizing experiments, the target materials can be defined as the container and the sample itself. The reduction of the activation from the container is easier than the reduction from the sample. Therefore, we tried to reduce the activation level by changing the container materials. In this paper, the results are displayed for some candidate container materials, such as polymethyl methacrylate, polystyrene, Glass, etc., with 45-MeV and 10-nA proton beams. As a result, PS is the most suitable material for the container because of its relatively low level of the activation by protons. Also the contribution of secondary produced neutrons to the activation is negligible.

  19. Moisture-Induced TBC Spallation on Turbine Blade Samples

    Science.gov (United States)

    Smialek, James

    2011-01-01

    Delayed failure of TBCs is a widely observed laboratory phenomenon, although many of the early observations went unreported. The weekend effect or DeskTop Spallation (DTS) is characterized by initial survival of a TBC after accelerated laboratory thermal cycling, then failure by exposure to ambient humidity or water. Once initiated, failure can occur quite dramatically in less than a second. To this end, the water drop test and digital video recordings have become useful techniques in studies at NASA (Smialek, Zhu, Cuy), DECHMA (Rudolphi, Renusch, Schuetze), and CNRS Toulouse/SNECMA (Deneux, Cadoret, Hervier, Monceau). In the present study the results for a commercial turbine blade, with a standard EB-PVD 7YSZ TBC top coat and Pt-aluminide diffusion bond coat are reported. Cut sections were intermittently oxidized at 1100, 1150, and 1200 C and monitored by weight change and visual appearance. Failures were distributed widely over a 5-100 hr time range, depending on temperature. At some opportune times, failure was captured by video recording, documenting the appearance and speed of the moisture-induced spallation process. Failure interfaces exhibited alumina scale grains, decorated with Ta-rich oxide particles, and alumina inclusions as islands and streamers. The phenomenon is thus rooted in moisture-induced delayed spallation (MIDS) of the alumina scale formed on the bond coat. In that regard, many studies show the susceptibility of alumina scales to moisture, as long as high strain energy and a partially exposed interface exist. The latter conditions result from severe cyclic oxidation conditions, which produce a highly stressed and partially damaged scale. In one model, it has been proposed that moisture reacts with aluminum in the bond coat to release hydrogen atoms that embrittle the interface. A negative synergistic effect with interfacial sulfur is also invoked.

  20. New spallation neutron sources, their performance and applications

    International Nuclear Information System (INIS)

    1985-01-01

    Pulsed spallation sources now operating in the world are at the KEK Laboratory in Japan (the KENS source), at Los Alamos National Laboratory (WNR) and at Argonne National Laboratory (IPNS), both the latter being in the US. The Intense Pulsed Neutron Source (IPNS) is currently the world's most intense source with a peak neutron flux of 4 x 10 14 n cm -2 s -1 at a repetition rate of 30 Hz, and globally producing approx. 1.5 x 10 15 n/sec. Present pulsed sources are still relatively weak compared to their potential. In 1985 the Rutherford Spallation Neutron Source will come on line, and eventually be approx. 30 more intense than the present IPNS. Later, in 1986 the WNR/PSR option at Los Alamos will make that facility of comparable intensity, while a subcritical fission booster at IPNS will keep IPNS competitive. These new sources will expand the applications of pulsed neutrons but are still based on accelerators built for other scientific purposes, usually nuclear or high-energy physics. Accelerator physicists are now designing machines expressly for spallation neutron research, and the proton currents attainable appear in the milliamps. (IPNS now runs at 0.5 GeV and 14 μA). Such design teams are at the KFA Laboratory Julich, Argonne National Laboratory and KEK. Characteristics, particularly the different time structure of the pulses, of these new sources will be discussed. Such machines will be expensive and require national, if not international, collaboration across a wide spectrum of scientific disciplines. The new opportunities for neutron research will, of course, be dramatic with these new sources

  1. Overview of the national spallation neutron source with emphasis on the target station

    International Nuclear Information System (INIS)

    Gabriel, T.A.; Barnes, J.N.; Charlton, L.A.

    1997-01-01

    The technologies that are being utilized to design and build a state-of-the-art neutron spallation source, the National Spallation Neutron Source (NSNS), are discussed. Emphasis is given to the technology issues that present the greatest scientific challenges. The present facility configuration, ongoing analysis and the planned hardware research and development program are also described

  2. Workshop: Research and development plans for high power spallation neutron testing at BNL

    International Nuclear Information System (INIS)

    1996-01-01

    This report consists of vugraphs from presentations at the meeting. The papers covered the following topics: (1) APS as a proton source; (2) target status for NSNS (National Spallation Neutron Source); (3) spallation neutron source in Japan; (4) liquid LiBi flow loop; and (5) research and development plans for high power tests at the AGS

  3. Research activities on structure materials of spallation neutron source at SINQ

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, G.S.; Dai, Y. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-09-01

    With the growing interests on powerful spallation neutron sources, especially with liquid metal targets, and accelerator driven energy systems, spallation materials science and technology have been received wide attention. At SINQ, material research activities are focused on: a) liquid metal corrosion; b) radiation damage; and c) interaction of corrosion and radiation damage. (author) 1 fig., refs.

  4. The trace element analysis of ancient Indian coins using proton induced x-ray emission (PIXE) technique

    International Nuclear Information System (INIS)

    PURI, N.K.; HAJIVALIEI, M.; BEDI, S.C.; SINGH, N.; GOVIL, I.M.; GARG, M.L.; HANDA, D.K.; GOVIL, K.L.; ROUT, B.; VIJAYAN, V.

    2004-01-01

    Elemental analysis of ancient Indian coins viz. thirty-three punched marked coins (6 th century B.C.), fifty-nine coins belonging to Kusanas (78-250 A.D) and twenty-five coins belonging to medieval period (11 th -14 th century A.D), from India have been analysed using Proton Induced X-ray Emission (PIXE) technique. The elements namely S, Ca, Fe, Ag, Cu, Ni and Pb were detected in most of the punch-marked coins while elements namely S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, As and Zn were detected in most of the Kusanas coins and the S, Ca, Fe, Cu, Ag, Sn, Pb were detected in 11 th -14 th century A.D. coins. Based on the elemental analysis different hypotheses put forward in the earlier literature were examined. This is the first attempt where reasonable number of ancient coins belonging to different periods were analysed by modern non destructive multi-elemental technique such as PIXE and has put the importance of the elemental analysis of ancient Indian coins in the proper perspective

  5. Analysis of Proton Induced Material Damage Using the DPA Cross-sections Based on NRT and BCA-MD Models

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyung-O; Roh, Gyuhong; Lee, Byungchul [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    The level of radiation induced material damage is mainly quantified by using the unit of Displacements Per Atom (DPA), and particularly, the displacement cross-section is used for characterizing/analyzing the radiation damage from incident neutrons and charged particles. Not long ago, the standard Norgett-Robinson-Torrens (NRT) model had been applied to produce the nuclear data due to its simplicity and implementation in commonly used codes, such as NJOY and MCNP codes. However, the evaluations based on NRT model represent the severe disagreement with experimental data and more accurate calculations. Hence, the evaluations with existing and new nuclear data are performed/compared in this study. It is assumed that a high energy proton beam is directly moved to the target, and a series of calculations are performed by using MCNPX code. The proton induced material damage is evaluated by using the displacement cross-sections, and the effect of nuclear data on the evaluation is specifically analyzed with MCNPX code. First, there is significant difference between the nuclear data from existing and new models, and the new evaluated data is generally lower than the existing one. Second, the position of maximum DPA is slightly differed with the position of maximum energy deposition, and the evaluation using new evaluated data is lower about 2 times than the other.

  6. Nuclear Dependence of Proton-Induced Drell-Yan Dimuon Production at 120 GeV at Seaquest

    Energy Technology Data Exchange (ETDEWEB)

    Dannowitz, Bryan P. [Illinois U., Urbana

    2016-01-01

    A measurement of the atomic mass (A) dependence of p + A → µ+µ- + X Drell-Yan dimuons produced by 120 GeV protons is presented here. The data was taken by the SeaQuest experiment at Fermilab using a proton beam extracted from its Main Injector. Over 61,000 dimuon pairs were recorded with invariant mass 4.2 < Mγ* < 10 GeV and target parton momentum fraction 0.1 ≤ x2 ≤ 0.5 for nuclear targets 1H, 2H, C, Fe, and W . The ratio of dimuon yields per nucleon (Y ) for heavy nuclei versus 2H, RDY = 2 2 Y (A)/Y ( H) ≈ u¯(A)(x)/u¯( H)(x), is sensitive to modifications in the anti-quark sea distributions in nuclei for the case of proton-induced Drell-Yan. The data analyzed here and in the future of SeaQuest will provide tighter constraints on various models that attempt to define the anomalous behavior of nuclear modification as seen in deep inelastic lepton scattering, a phenomenon generally known as the EMC effect.

  7. VESPA: The vibrational spectrometer for the European Spallation Source

    Energy Technology Data Exchange (ETDEWEB)

    Fedrigo, Anna, E-mail: anna.fedrigo@nbi.ku.dk [Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen Ø (Denmark); Istituto dei Sistemi Complessi, Consiglio Nazionale delle Ricerche, 50019 Sesto Fiorentino (Italy); European Spallation Source ESS AB, SE-221 00 Lund (Sweden); Colognesi, Daniele; Grazzi, Francesco; Zoppi, Marco [Istituto dei Sistemi Complessi, Consiglio Nazionale delle Ricerche, 50019 Sesto Fiorentino (Italy); Bertelsen, Mads; Strobl, Markus [Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen Ø (Denmark); European Spallation Source ESS AB, SE-221 00 Lund (Sweden); Hartl, Monika; Deen, Pascale P. [European Spallation Source ESS AB, SE-221 00 Lund (Sweden); Lefmann, Kim [Niels Bohr Institute, University of Copenhagen, 2100 Copenhagen Ø (Denmark)

    2016-06-15

    VESPA, Vibrational Excitation Spectrometer with Pyrolytic-graphite Analysers, aims to probe molecular excitations via inelastic neutron scattering. It is a thermal high resolution inverted geometry time-of-flight instrument designed to maximise the use of the long pulse of the European Spallation Source. The wavelength frame multiplication technique was applied to provide simultaneously a broad dynamic range (about 0-500 meV) while a system of optical blind choppers allows to trade flux for energy resolution. Thanks to its high flux, VESPA will allow the investigation of dynamical and in situ experiments in physical chemistry. Here we describe the design parameters and the corresponding McStas simulations.

  8. Beginnings of remote handling at the RAL Spallation Neutron Source

    International Nuclear Information System (INIS)

    Liska, D.J.; Hirst, J.

    1985-01-01

    Expenditure of funds and resources for remote maintenance systems traditionally are delayed until late in an accelerator's development. However, simple remote-surveillance equipment can be included early in facility planning to set the stage for future remote-handling needs and to identify appropriate personnel. Some basic equipment developed in the UK at the Spallation Neutron Source (SNS) that serves this function and that has been used to monitor beam loss during commissioning is described. A photograph of this equipment, positioned over the extractor septum magnet, is shown. This method can serve as a pattern approach to the problem of initiating remote-handling activities in other facilities

  9. Spallation neutron source target station design, development, and commissioning

    Energy Technology Data Exchange (ETDEWEB)

    Haines, J.R., E-mail: hainesjr@ornl.gov; McManamy, T.J.; Gabriel, T.A.; Battle, R.E.; Chipley, K.K.; Crabtree, J.A.; Jacobs, L.L.; Lousteau, D.C.; Rennich, M.J.; Riemer, B.W.

    2014-11-11

    The spallation neutron source target station is designed to safely, reliably, and efficiently convert a 1 GeV beam of protons to a high flux of about 1 meV neutrons that are available at 24 neutron scattering instrument beam lines. Research and development findings, design requirements, design description, initial checkout testing, and results from early operation with beam are discussed for each of the primary target subsystems, including the mercury target, neutron moderators and reflector, surrounding vessels and shielding, utilities, remote handling equipment, and instrumentation and controls. Future plans for the mercury target development program are also briefly discussed.

  10. Nondiffractive applications of neutrons at the spallation source SINQ

    International Nuclear Information System (INIS)

    Lehmann, E.

    1996-01-01

    The paper delivers an overview about experiments with neutrons from the spallation source SINQ which are not especially devoted to neutron scattering. A total of six experimental facilities are under construction using thermal as well as cold neutrons. Starting with some general considerations about the interaction of neutrons with matter, the principles, boundary conditions and the experimental set up of these experiments are described briefly. Some more details are given for the neutron radiography facility NEUTRA as the author's special interest and research field. (author) 7 figs., 2 tabs., 9 refs

  11. Radiation damage for the spallation target of ADS

    International Nuclear Information System (INIS)

    Fan Sheng; Ye Yanlin; Xu Chuncheng; Chen Tao; Sobolevsky, N.M.

    2000-01-01

    By using SHIELD codes system, the authors investigate the radiation damage, such as radiation damage cross section, displacement atom cross section and the rate of displacement atom, gas production cross section, the rate of gas production and the ratio, R, of the helium and displacement production rates in target, container window and spallation neutron source materials as W and Pb induced from intermediate energy proton and neutron incident. And the study of radiation damage in the thick Pb target with long 60 cm, radius 20 cm is presented

  12. Nondiffractive applications of neutrons at the spallation source SINQ

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, E [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1996-11-01

    The paper delivers an overview about experiments with neutrons from the spallation source SINQ which are not especially devoted to neutron scattering. A total of six experimental facilities are under construction using thermal as well as cold neutrons. Starting with some general considerations about the interaction of neutrons with matter, the principles, boundary conditions and the experimental set up of these experiments are described briefly. Some more details are given for the neutron radiography facility NEUTRA as the author`s special interest and research field. (author) 7 figs., 2 tabs., 9 refs.

  13. Plans for a new pulsed spallation source at Los Alamos

    International Nuclear Information System (INIS)

    Pynn, R.

    1993-01-01

    Los Alamos National Laboratory has proposed to change the emphasis of research at its Meson Physics Facility (LAWF) by buabg a new pulsed spallation source for neutron scattering research. The new source would have a beam power of about one megawatt shared between two neutron production targets, one operating at 20 Hz and the other at 40 Hz. It would make use of much of the existing proton linac and would be designed to accommodate a later upgrade to a beam power of 5 MW or so. A study of technical feasibility is underway and will be published later this year

  14. Fission fragment angular distributions in proton-induced fission of 209Bi (p,f) and 197Au (p,f)

    International Nuclear Information System (INIS)

    Soheily, S.; Noshad, H.; Lamehi-Rashti, M.

    2002-01-01

    The fission fragment angular distributions have been measured for proton-induced fission of 209 B i and 197 A u nuclei using surface barrier detectors at several energies between 25 MeV and 30 MeV. The experimental anisotropies are found to be in agreement with the predictions of the Standard Saddle-Point Statistical Model. The fission cross sections of 209 B i and 197 A u nuclei were also measured and compared with the previous works

  15. Preparation and characterization of a new set of IAEA reference air filters using instrumental neutron activation analysis, proton-induced X-ray emission and Rutherford backscattering

    Czech Academy of Sciences Publication Activity Database

    Kučera, Jan; Havránek, Vladimír; Krausová, Ivana

    2009-01-01

    Roč. 281, č. 1 (2009), s. 123-129 ISSN 0236-5731. [9th International Conference on Nuclear Analytical Methods in the Life Sciences. Lisbon, 07.09.2008-12.09.2008] Institutional research plan: CEZ:AV0Z10480505 Keywords : Reference air filters * instrumental neutron activation analysis * Proton induced X-ray emission Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.631, year: 2009

  16. Insights into the π-p → ηn reaction mechanism

    International Nuclear Information System (INIS)

    Durand, J.; Julia-Diaz, B.; Julia-Diaz, B.; Julia-Diaz, B.; Lee, T.S.H.; Sato, T.; Lee, T.S.H.; Sato, T.

    2009-01-01

    A dynamical coupled-channels formalism is used to investigate the eta-meson production mechanism on the proton induced by pions, in the total center-of-mass energy region from threshold up to 2 GeV. We show how and why studying exclusively total cross section data might turn out to be misleading in pinning down the reaction mechanism. (authors)

  17. Radiation problems expected for the German spallation neutron source

    International Nuclear Information System (INIS)

    Goebel, K.

    1981-01-01

    The German project for the construction of a Spallation Neutron Source with high proton beam power (5.5 MW) will have to cope with a number of radiation problems. The present report describes these problems and proposes solutions for keeping exposures for the staff and release of activity and radiation into the environment as low as reasonably achievable. It is shown that the strict requirements of the German radiation protection regulations can be met. The main problem will be the exposure of maintenance personnel to remanent gamma radiation, as is the case at existing proton accelerators. Closed ventilation and cooling systems will reduce the release of (mainly short-lived) activity to acceptable levels. Shielding requirements for different sections are discussed, and it is demonstrated by calculations and extrapolations from experiments that fence-post doses well below 150 mrem/y can be obtained at distances of the order of 100 metres from the principal source points. The radiation protection system proposed for the Spallation Neutron Source is discussed, in particular the needs for monitor systems and a central radiation protection data base and alarm system. (orig.)

  18. Materials considerations for the National Spallation Neutron Source target

    International Nuclear Information System (INIS)

    Mansur, L.K.; DiStefano, J.R.; Farrell, K.; Lee, E.H.; Pawel, S.J.; Wechsler, M.S.

    1997-08-01

    The National Spallation Neutron Source (NSNS), in which neutrons are generated by bombarding a liquid mercury target with 1 GeV protons, will place extraordinary demands on materials performance. The target structural material will operate in an aggressive environment, subject to intense fluxes of high energy protons, neutrons, and other particles, while exposed to liquid mercury and to water. Components that require special consideration include the Hg liquid target container and protective shroud, beam windows, support structures, moderator containers, and beam tubes. In response to these demands a materials R and D program has been developed for the NSNS that includes: selection of materials; calculations of radiation damage; irradiations, post irradiation testing, and characterization; compatibility testing and characterization; design and implementation of a plan for monitoring of materials performance in service; and materials engineering and technical support to the project. Irradiations are being carried out in actual and simulated spallation environments. Compatibility experiments in Hg are underway to ascertain whether the phenomena of liquid metal embrittlement and temperature gradient mass transfer will be significant. Results available to date are assessed in terms of the design and operational performance of the facility

  19. Complementarity of long pulse and short pulse spallation sources

    Energy Technology Data Exchange (ETDEWEB)

    Mezei, F [Hahn-Meitner-Institut Berlin GmbH (Germany)

    1995-11-01

    The complementarity of short pulse spallation sources (SPSS) and steady state (CW) reactors is a widely accepted concept. SPSS and long pulse spallation sources (LPSS) are complementary in two ways: (a) in their performance in neutron scattering experiments LPSS closely emulate CW reactors. In this respect two facets of the time-of-flight (TOF) monochromator method adequate for LPSS will be discussed: the superiority of the TOF approach to the crystal monochromator method in high resolution powder diffraction, and the novel technique of repetition rate multiplication in TOF spectroscopy, (b) LPSS combined with adequate chopper systems can also emulate SPSS in a number of applications. It will be shown that the LPSS method of producing short neutron pulses is more efficient for cold and thermal neutrons (below an energy of about 100 MeV), while SPSS is the more favourable approach for hot, epithermal neutrons, i.e. in the slowing down regime in contrast to the moderated regime. These two aspects of complementarity of LPSS and SPSS lead to the conclusions that for about 75% of the spectrum of neutron scattering experiments as known of today the LPSS approach is the most advantageous one with a feasible neutron intensity exceeding that available at ILL by a factor of about 30, while for the remaining 25% of applications the SPSS technique is superior with a well-known potential of a similar gain over present day performances. (author) 7 figs., 6 refs.

  20. Complementarity of long pulse and short pulse spallation sources

    International Nuclear Information System (INIS)

    Mezei, F.

    1995-01-01

    The complementarity of short pulse spallation sources (SPSS) and steady state (CW) reactors is a widely accepted concept. SPSS and long pulse spallation sources (LPSS) are complementary in two ways: a) in their performance in neutron scattering experiments LPSS closely emulate CW reactors. In this respect two facets of the time-of-flight (TOF) monochromator method adequate for LPSS will be discussed: the superiority of the TOF approach to the crystal monochromator method in high resolution powder diffraction, and the novel technique of repetition rate multiplication in TOF spectroscopy, b) LPSS combined with adequate chopper systems can also emulate SPSS in a number of applications. It will be shown that the LPSS method of producing short neutron pulses is more efficient for cold and thermal neutrons (below an energy of about 100 MeV), while SPSS is the more favourable approach for hot, epithermal neutrons, i.e. in the slowing down regime in contrast to the moderated regime. These two aspects of complementarity of LPSS and SPSS lead to the conclusions that for about 75% of the spectrum of neutron scattering experiments as known of today the LPSS approach is the most advantageous one with a feasible neutron intensity exceeding that available at ILL by a factor of about 30, while for the remaining 25% of applications the SPSS technique is superior with a well-known potential of a similar gain over present day performances. (author) 7 figs., 6 refs

  1. Ranking and validation of spallation models for isotopic production cross sections of heavy residua

    Science.gov (United States)

    Sharma, Sushil K.; Kamys, Bogusław; Goldenbaum, Frank; Filges, Detlef

    2017-07-01

    The production cross sections of isotopically identified residual nuclei of spallation reactions induced by 136Xe projectiles at 500AMeV on hydrogen target were analyzed in a two-step model. The first stage of the reaction was described by the INCL4.6 model of an intranuclear cascade of nucleon-nucleon and pion-nucleon collisions whereas the second stage was analyzed by means of four different models; ABLA07, GEM2, GEMINI++ and SMM. The quality of the data description was judged quantitatively using two statistical deviation factors; the H-factor and the M-factor. It was found that the present analysis leads to a different ranking of models as compared to that obtained from the qualitative inspection of the data reproduction. The disagreement was caused by sensitivity of the deviation factors to large statistical errors present in some of the data. A new deviation factor, the A factor, was proposed, that is not sensitive to the statistical errors of the cross sections. The quantitative ranking of models performed using the A-factor agreed well with the qualitative analysis of the data. It was concluded that using the deviation factors weighted by statistical errors may lead to erroneous conclusions in the case when the data cover a large range of values. The quality of data reproduction by the theoretical models is discussed. Some systematic deviations of the theoretical predictions from the experimental results are observed.

  2. Ranking and validation of spallation models for isotopic production cross sections of heavy residua

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Sushil K.; Kamys, Boguslaw [Jagiellonian University, The Marian Smoluchowski Institute of Physics, Krakow (Poland); Goldenbaum, Frank; Filges, Detlef [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany)

    2017-07-15

    The production cross sections of isotopically identified residual nuclei of spallation reactions induced by {sup 136}Xe projectiles at 500 AMeV on hydrogen target were analyzed in a two-step model. The first stage of the reaction was described by the INCL4.6 model of an intranuclear cascade of nucleon-nucleon and pion-nucleon collisions whereas the second stage was analyzed by means of four different models; ABLA07, GEM2, GEMINI++ and SMM. The quality of the data description was judged quantitatively using two statistical deviation factors; the H-factor and the M-factor. It was found that the present analysis leads to a different ranking of models as compared to that obtained from the qualitative inspection of the data reproduction. The disagreement was caused by sensitivity of the deviation factors to large statistical errors present in some of the data. A new deviation factor, the A factor, was proposed, that is not sensitive to the statistical errors of the cross sections. The quantitative ranking of models performed using the A-factor agreed well with the qualitative analysis of the data. It was concluded that using the deviation factors weighted by statistical errors may lead to erroneous conclusions in the case when the data cover a large range of values. The quality of data reproduction by the theoretical models is discussed. Some systematic deviations of the theoretical predictions from the experimental results are observed. (orig.)

  3. Range verification for eye proton therapy based on proton-induced x-ray emissions from implanted metal markers

    Science.gov (United States)

    La Rosa, Vanessa; Kacperek, Andrzej; Royle, Gary; Gibson, Adam

    2014-06-01

    Metal fiducial markers are often implanted on the back of the eye before proton therapy to improve target localization and reduce patient setup errors. We aim to detect characteristic x-ray emissions from metal targets during proton therapy to verify the treatment range accuracy. Initially gold was chosen for its biocompatibility properties. Proton-induced x-ray emissions (PIXE) from a 15 mm diameter gold marker were detected at different penetration depths of a 59 MeV proton beam at the CATANA proton facility at INFN-LNS (Italy). The Monte Carlo code Geant4 was used to reproduce the experiment and to investigate the effect of different size markers, materials, and the response to both mono-energetic and fully modulated beams. The intensity of the emitted x-rays decreases with decreasing proton energy and thus decreases with depth. If we assume the range to be the depth at which the dose is reduced to 10% of its maximum value and we define the residual range as the distance between the marker and the range of the beam, then the minimum residual range which can be detected with 95% confidence level is the depth at which the PIXE peak is equal to 1.96 σbkg, which is the standard variation of the background noise. With our system and experimental setup this value is 3 mm, when 20 GyE are delivered to a gold marker of 15 mm diameter. Results from silver are more promising. Even when a 5 mm diameter silver marker is placed at a depth equal to the range, the PIXE peak is 2.1 σbkg. Although these quantitative results are dependent on the experimental setup used in this research study, they demonstrate that the real-time analysis of the PIXE emitted by fiducial metal markers can be used to derive beam range. Further analysis are needed to demonstrate the feasibility of the technique in a clinical setup.

  4. Constraining astrophysical reaction rates: using the storage rings at FAIR/GSI

    Science.gov (United States)

    Langer, Christoph; Glorius, Jan; Slavkovská, Zuzana; Litvinov, Sergey; Litvinov, Yuri A.; Reifarth, René

    2018-01-01

    Ion optical calculations for a storage ring at the present GSI facility for direct proton-induced reactions relevant for different astrophysical processes are presented. As an example case, the 59Cu(p,γ) and 59Cu(p,α) reactions are shown. The branching of these two reactions is important in X-ray burst scenarios, since it determines the breakout out of the major 56Ni waiting point.

  5. Neutronic performance issues for the Spallation Neutron Source moderators

    International Nuclear Information System (INIS)

    Iverson, E.B.; Murphy, B.D.

    2001-01-01

    We continue to develop the neutronic models of the Spallation Neutron Source target station and moderators in order to better predict the neutronic performance of the system as a whole and in order to better optimize that performance. While we are not able to say that every model change leads to more intense neutron beams being predicted, we do feel that such changes are advantageous in either performance or in the accuracy of the prediction of performance. We have computationally and experimentally studied the neutronics of hydrogen-water composite moderators such as are proposed for the SNS Project. In performing these studies, we find that the composite moderator, at least in the configuration we have examined, does not provide performance characteristics desirable for the instruments proposed and being designed for this neutron scattering facility. The pulse width as a function of energy is significantly broader than for other moderators, limiting attainable resolution-bandwidth combinations. Furthermore, there is reason to expect that higher-energy (0.1-1 eV) applications will be significantly impacted by bimodal pulse shapes requiring enormous effort to parameterize. As a result of these studies, we have changed the SNS design, and will not use a composite moderator at this time. We have analyzed the depletion of a gadolinium poison plate in a hydrogen moderator at the Spallation Neutron Source, and found that conventional poison thicknesses will be completely unable to last the desired component lifetime of three operational years. A poison plate 300-600 μm thick will survive for the required length of time, but will somewhat degrade the intensity (by as much as 15% depending on neutron energy) and the consistency of the neutron source performance. Our results should scale fairly easily to other moderators on this or any other spallation source. While depletion will be important for all highly-absorbing materials in high-flux regions, we feel it likely that

  6. Cosmic ray-induced spallation recoil tracks in meteoritic phosphates: simulation at the CERN synchrocyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Perron, C [Centre National de la Recherche Scientifique (CNRS), 75 - Paris (France). Inst. d` Astrophysique; [Museum National d` Histoire Naturelle, 75 - Paris (France)

    1994-12-31

    Annealed meteoritic phosphate crystals have been irradiated by 600 MeV protons to simulate cosmic ray irradiation in space. Spallation recoil tracks were then revealed, which mimic fission tracks, specially when observed in the SEM. A production yield of 9.3 {+-} 2.2 x 10{sup 8} spallation track per proton has been obtained for merrillite, and a substantially lower value (2.5 per proton) for apatite. A nominal production yield in space of 6 tracks per year has been derived, which may be used for a rough estimate of spallation track densities in chondritic merrillite. (Author).

  7. The effect of annealing and desulfurization on oxide spallation of turbine airfoil material

    International Nuclear Information System (INIS)

    Briant, C.L.; Murphy, W.H.; Schaeffer, J.C.

    1995-01-01

    In this paper the authors report a study that addresses the sulfur-induced spallation theory. Previous work has shown that a high temperature anneal in hydrogen desulfurizes nickel-base alloys and greatly improves their resistance to oxide spallation. The authors will show that such an anneal can be applied successfully to a Ni-base airfoil material. Both Auger segregation experiments and chemical analyses show that this anneal desulfurizes the material, at least in the absence of yttrium. However, the results suggest that factors other than desulfurization may be contributing to the improvement in spallation resistance produced by the anneal

  8. The concept of a European spallation neutron source (ESS)

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, G.S. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-11-01

    The next generation neutron source in Europe, which was studied by a collaboration between twelve laboratories, has been conceived as a 5 MW short pulse spallation source because of the superior overall scientific potential attributed to such a facility relative to all other options considered. While the accelerator side can use essentially established technology with some extensions in performance, a novel target concept based on the use of Mercury as a flowing liquid metal target was developed, which is not only expected to lead the way further into the future, but which was also found to give the best neutronic performance of all known choices. Close permanent interaction with a large user community yielded important input for the concept in general and for the upcoming R and D and design phases in particular. (author)

  9. Radiological Hazard of Spallation Products in Accelerator-Driven System

    International Nuclear Information System (INIS)

    Saito, M.; Stankovskii, A.; Artisyuk, V.; Korovin, Yu.; Shmelev, A.; Titarenko, Yu.

    2002-01-01

    The central issue underlying this paper is related to elucidating the hazard of radioactive spallation products that might be an important factor affecting the design option of accelerator-driven systems (ADSs). Hazard analysis based on the concept of Annual Limit on Intake identifies alpha-emitting isotopes of rare earths (REs) (dysprosium, gadolinium, and samarium) as the dominant contributors to the overall toxicity of traditional (W, Pb, Pb-Bi) targets. The matter is addressed from several points of view: code validation to simulate their yields, choice of material for the neutron producing targets, and challenging the beam type. The paper quantitatively determines the domain in which the toxicity of REs exceeds that of polonium activation products broadly discussed now in connection with advertising lead-bismuth technology for the needs of ADSs

  10. The Spallation Neutron Source (SNS) conceptual design shielding analysis

    International Nuclear Information System (INIS)

    Johnson, J.O.; Odano, N.; Lillie, R.A.

    1998-03-01

    The shielding design is important for the construction of an intense high-energy accelerator facility like the proposed Spallation Neutron Source (SNS) due to its impact on conventional facility design, maintenance operations, and since the cost for the radiation shielding shares a considerable part of the total facility costs. A calculational strategy utilizing coupled high energy Monte Carlo calculations and multi-dimensional discrete ordinates calculations, along with semi-empirical calculations, was implemented to perform the conceptual design shielding assessment of the proposed SNS. Biological shields have been designed and assessed for the proton beam transport system and associated beam dumps, the target station, and the target service cell and general remote maintenance cell. Shielding requirements have been assessed with respect to weight, space, and dose-rate constraints for operating, shutdown, and accident conditions. A discussion of the proposed facility design, conceptual design shielding requirements calculational strategy, source terms, preliminary results and conclusions, and recommendations for additional analyses are presented

  11. Study on induced radioactivity of China Spallation Neutron Source

    International Nuclear Information System (INIS)

    Wu Qingbiao; Wang Qingbin; Wu Jingmin; Ma Zhongjian

    2011-01-01

    China Spallation Neutron Source (CSNS) is the first High Energy Intense Proton Accelerator planned to be constructed in China during the State Eleventh Five-Year Plan period, whose induced radioactivity is very important for occupational disease hazard assessment and environmental impact assessment. Adopting the FLUKA code, the authors have constructed a cylinder-tunnel geometric model and a line-source sampling physical model, deduced proper formulas to calculate air activation, and analyzed various issues with regard to the activation of different tunnel parts. The results show that the environmental impact resulting from induced activation is negligible, whereas the residual radiation in the tunnels has a great influence on maintenance personnel, so strict measures should be adopted.(authors)

  12. Electron Cloud Mitigation in the Spallation Neutron Source Ring

    International Nuclear Information System (INIS)

    Wei, J.; Blaskiewicz, Michael; Brodowski, J.; Cameron, P.; Davino, Daniele; Fedotov, A.; He, P.; Hseuh, H.; Lee, Y.Y.; Ludewig, H.; Meng, W.; Raparia, D.; Tuozzolo, J.; Zhang, S.Y.; Catalan-Lasheras, N.; Macek, R.J.; Furman, Miguel A.; Aleksandrov, A.; Cousineau, S.; Danilov, V.; Henderson, S.

    2008-01-01

    The Spallation Neutron Source (SNS) accumulator ring is designed to accumulate, via H - injection, protons of 2 MW beam power at 1 GeV kinetic energy at a repetition rate of 60 Hz [1]. At such beam intensity, electron-cloud is expected to be one of the intensity-limiting mechanisms that complicate ring operations. This paper summarizes mitigation strategy adopted in the design, both in suppressing electron-cloud formation and in enhancing Landau damping, including tapered magnetic field and monitoring system for the collection of stripped electrons at injection, TiN coated beam chamber for suppression of the secondary yield, clearing electrodes dedicated for the injection region and parasitic on BPMs around the ring, solenoid windings in the collimation region, and planning of vacuum systems for beam scrubbing upon operation

  13. Characteristics of the WNR: a pulsed spallation neutron source

    International Nuclear Information System (INIS)

    Russell, G.J.; Lisowski, P.W.; Howe, S.D.; King, N.S.P.; Meier, M.M.

    1982-01-01

    The Weapons Neutron Research facility (WNR) is a pulsed spallation neutron source in operation at the Los Alamos National Laboratory. The WNR uses part of the 800-MeV proton beam from the Clinton P. Anderson Meson Physics Facility accelerator. By choosing different target and moderator configurations and varying the proton pulse structure, the WNR can provide a white neutron source spanning the energy range from a few MeV to 800 MeV. The neutron spectrum from a bare target has been measured and is compared with predictions using an Intranuclear Cascade model coupled to a Monte Carlo transport code. Calculations and measurements of the neutronics of WNR target-moderator assemblies are presented

  14. Magnets for the national spallation neutron source accumulator ring

    International Nuclear Information System (INIS)

    Tuozzolo, J.; Brodowski, J.; Danby, G.

    1997-01-01

    The National Spallation Neutron Source Accumulator Ring will require large aperture dipole magnets, strong focusing quadrupole magnets, and smaller low field dipole, quadrupole, and sextupole correcting magnets. All of the magnets will provide a fixed magnetic field throughout the accumulator's fill/storage/extraction cycle. Similar fixed field magnets will also be provided for the beam transport systems. Because of the high intensity in the accumulator, the magnets must be designed with high tolerances for optimum field quality and for the high radiation environment which may be present at the injection/extraction areas, near the collimators, and near the target area. Field specifications and field plots are presented as well as planned fabrication methods and procedures, cooling system design, support, and installation

  15. The Spallation Neutron Source Beam Commissioning and Initial Operations

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, Stuart [Argonne National Lab. (ANL), Argonne, IL (United States); Aleksandrov, Alexander V. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Allen, Christopher K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Assadi, Saeed [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bartoski, Dirk [University of Texas, Houston, TX (United States). Anderson Cancer Center; Blokland, Willem [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Casagrande, F. [Michigan State Univ., East Lansing, MI (United States); Campisi, I. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Chu, C. [Michigan State Univ., East Lansing, MI (United States); Cousineau, Sarah M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Crofford, Mark T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Danilov, Viatcheslav [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Deibele, Craig E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dodson, George W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Feshenko, A. [Inst. for Nuclear Research (INR), Moscow (Russian Federation); Galambos, John D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Han, Baoxi [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hardek, T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Holmes, Jeffrey A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Holtkamp, N. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Howell, Matthew P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jeon, D. [Inst. for Basic Science, Daejeon (Korea); Kang, Yoon W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kasemir, Kay [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kim, Sang-Ho [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kravchuk, L. [Institute for Nuclear Research (INR), Moscow (Russian Federation); Long, Cary D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); McManamy, T. [McManamy Consulting, Inc., Middlesex, MA (United States); Pelaia, II, Tom [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Piller, Chip [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Plum, Michael A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Pogge, James R. [Tennessee Technological Univ., Cookeville, TN (United States); Purcell, John David [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Shea, T. [European Spallation Source, Lund (Sweden); Shishlo, Andrei P [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sibley, C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Stockli, Martin P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Stout, D. [Michigan State Univ., East Lansing, MI (United States); Tanke, E. [European Spallation Source, Lund (Sweden); Welton, Robert F [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Zhang, Y. [Michigan State Univ., East Lansing, MI (United States); Zhukov, Alexander P [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-01

    The Spallation Neutron Source (SNS) accelerator delivers a one mega-Watt beam to a mercury target to produce neutrons used for neutron scattering materials research. It delivers ~ 1 GeV protons in short (< 1 us) pulses at 60 Hz. At an average power of ~ one mega-Watt, it is the highest-powered pulsed proton accelerator. The accelerator includes the first use of superconducting RF acceleration for a pulsed protons at this energy. The storage ring used to create the short time structure has record peak particle per pulse intensity. Beam commissioning took place in a staged manner during the construction phase of SNS. After the construction, neutron production operations began within a few months, and one mega-Watt operation was achieved within three years. The methods used to commission the beam and the experiences during initial operation are discussed.

  16. Neutron cross sections for the interpretation of a spallation experiment

    International Nuclear Information System (INIS)

    Bortignon, P.F.; Mariani, F.; Perini, A.; Sangiust, V.

    1994-01-01

    An irradiation was carried out in a spallation neutron spectrum at the beam stop of LAMPF (Los Alamos); many activation detectors were used in order to obtain a fluence mapping inside the capsule volume. The cross sections were derived from ENDF B/V Dosimetry File up to 20 MeV and were based on calculations with the code ALICE up to 200 MeV. From 200 to 800 MeV an empirical extrapolation was employed since no data, calculated or measured, were available at the moment. An attempt has been made in this paper to revisit the interpretation of the experiment reconsidering the cross sections in the energy range from 200 to 800 MeV as given by the semiempirical models of Rudstam, Silberger and Tsao and Hufner

  17. Thermal shock analysis of liquid-mercury spallation target

    CERN Document Server

    Ishikura, S; Futakawa, M; Hino, R; Date, H

    2002-01-01

    The developments of the neutron scattering facilities are carried out under the high-intensity proton accelerator project promoted by JAERI and KEK. To estimate the structural integrity of the heavy liquid-metal (Hg) target used as a spallation neutron source in a MW-class neutron scattering facility, dynamic stress behavior due to the incident of a 1 MW-pulsed proton beam was analyzed by using FEM code. Two-type target containers with semi-cylindrical type and flat-plate type window were used as models for analyses. As a result, it is confirmed that the stress (pressure wave) generated by dynamic thermal shock becomes the largest at the center of window, and the flat-plate type window is more advantageous from the structural viewpoint than the semi-cylindrical type window. It has been understood that the stress generated in the window by the pressure wave can be treated as the secondary stress. (author)

  18. Beam Instrumentation for the Spallation Neutron Source Ring

    International Nuclear Information System (INIS)

    Witkover, R. L.; Cameron, P. R.; Shea, T. J.; Connolly, R. C.; Kesselman, M.

    1999-01-01

    The Spallation Neutron Source (SNS) will be constructed by a multi-laboratory collaboration with BNL responsible for the transfer lines and ring. The 1 MW beam power necessitates careful monitoring to minimize un-controlled loss. This high beam power will influence the design of the monitors in the high energy beam transport line (HEBT) from linac to ring, in the ring, and in the ring-to-target transfer line (RTBT). The ring instrumentation must cover a 3-decade range of beam intensity during accumulation. Beam loss monitoring will be especially critical since un-controlled beam loss must be kept below 10 -4 . A Beam-In-Gap (BIG) monitor is being designed to assure out-of-bucket beam will not be lost in the ring

  19. Electron-cloud mitigation in the spallation neutron source ring

    International Nuclear Information System (INIS)

    Wei, J.; Blaskiewicz, M.; Brodowski, J.; Cameron, P.; Davino, D.; Fedotov, A.; He, P.; Hseuh, H.; Lee, Y.Y.; Meng, W.; Raparia, D.; Tuozzolo, J.; Zhang, S.Y.; Danilov, V.; Henderson, S.; Furman, M.; Pivi, M.; Macek, R.

    2003-01-01

    The Spallation Neutron Source (SNS) accumulator ring is designed to accumulate, via H- injection, protons of 2 MW beam power at 1 GeV kinetic energy at a repetition rate of 60 Hz [1]. At such beam intensity, electron cloud is expected to be one of the intensity-limiting mechanisms that complicate ring operations. This paper summarizes mitigation strategy adopted in the design, both in suppressing electron-cloud formation and in enhancing Landau damping, including tapered magnetic field and monitoring system for the collection of stripped electrons at injection, TiN coated beam chamber for suppression of the secondary yield, clearing electrodes dedicated for the injection region and parasitic on BPMs around the ring, solenoid windings in the collimation region, and planning of vacuum systems for beam scrubbing upon operation

  20. Basic aspects of spallation radiation damage to materials

    Energy Technology Data Exchange (ETDEWEB)

    Wechsler, M.S.; Lin, C. [North Carolina State Univ., Raleigh, NC (United States); Sommer, W.F. [Los Alamos National Laboratory, NM (United States)

    1995-10-01

    The nature of radiation effects, as learned from investigations using reactor neutron irradiations, is reviewed, and its relevance to spallation radiation damage to materials in accelerator-driven neutron sources is discussed. Property changes upon irradiation are due to (1) displaced atoms, producing vacancy and interstitial defect clusters, which cause radiation hardening and embrittlement; (2) helium production, the helium then forming bubbles, which engenders high-temperature grain-boundary fracture; and (3) transmutations, which means that impurity concentrations are introduced. Methods for analyzing displacement production are related, and recent calculations of displacement cross sections using SPECTER and LAHET are described, with special reference to tungsten, a major candidate for a target material in accelerator-driven neutron systems.

  1. Materials compatibility studies for the Spallation Neutron Source

    International Nuclear Information System (INIS)

    DiStefano, J.R.; Pawel, S.J.; Manneschmidt, E.T.

    1998-01-01

    The Spallation Neutron Source (SNS) is a high power facility for producing neutrons that utilizes flowing liquid mercury inside an austenitic stainless steel container as the target for a 1.0 GeV proton beam. Type 316 SS has been selected as the container material for the mercury and consequences of exposure of 316 SS to radiation, thermal shock, thermal stress, cavitation and hot, flowing mercury are all being addressed by R and D programs. In addition, corrosion studies also include evaluation of Inconel 718 because it has been successfully used in previous spallation neutron systems as a window material. Two types of compatibility issues relative to 316 SS/mercury and Inconel 718/mercury are being examined: (1) liquid metal embrittlement (LME) and (2) temperature gradient mass transfer. Studies have shown that mercury does not easily wet type 316 SS below 275 C. In the LME experiments, attempts were made to promote wetting of the steel by mercury either by adding gallium to the mercury or coating the specimen with a tin-silver solder that the mercury easily wets. The latter proved more reliable in establishing wetting, but there was no evidence of LME in any of the constant extension rate tensile tests either at 23 or 100 C. Inconel 718 also showed no change in room temperature properties when tested in mercury or mercury-gallium. However, there was evidence that the fracture was less ductile. Preliminary evaluation of mass transfer of either type 316 SS or Inconel 718 in mercury or mercury-gallium at 350 C (maximum temperature) did not reveal significant effects. Two 5,000 h thermal convection loop tests of type 316 SS are in progress, with specimens in both hot and cold test regions, at 300 and 240 C, respectively

  2. Range verification for eye proton therapy based on proton-induced x-ray emissions from implanted metal markers

    International Nuclear Information System (INIS)

    Rosa, Vanessa La; Royle, Gary; Gibson, Adam; Kacperek, Andrzej

    2014-01-01

    Metal fiducial markers are often implanted on the back of the eye before proton therapy to improve target localization and reduce patient setup errors. We aim to detect characteristic x-ray emissions from metal targets during proton therapy to verify the treatment range accuracy. Initially gold was chosen for its biocompatibility properties. Proton-induced x-ray emissions (PIXE) from a 15 mm diameter gold marker were detected at different penetration depths of a 59 MeV proton beam at the CATANA proton facility at INFN-LNS (Italy). The Monte Carlo code Geant4 was used to reproduce the experiment and to investigate the effect of different size markers, materials, and the response to both mono-energetic and fully modulated beams. The intensity of the emitted x-rays decreases with decreasing proton energy and thus decreases with depth. If we assume the range to be the depth at which the dose is reduced to 10% of its maximum value and we define the residual range as the distance between the marker and the range of the beam, then the minimum residual range which can be detected with 95% confidence level is the depth at which the PIXE peak is equal to 1.96 σ bkg , which is the standard variation of the background noise. With our system and experimental setup this value is 3 mm, when 20 GyE are delivered to a gold marker of 15 mm diameter. Results from silver are more promising. Even when a 5 mm diameter silver marker is placed at a depth equal to the range, the PIXE peak is 2.1 σ bkg . Although these quantitative results are dependent on the experimental setup used in this research study, they demonstrate that the real-time analysis of the PIXE emitted by fiducial metal markers can be used to derive beam range. Further analysis are needed to demonstrate the feasibility of the technique in a clinical setup. (paper)

  3. The WNR facility - a pulsed spallation neutron source at the Los Alamos Scientific Laboratory

    International Nuclear Information System (INIS)

    Russell, G.J.; Lisowski, P.W.; King, N.S.P.

    1978-01-01

    The Weapons Neutron Research facility (WNR) at the Los Alamos Scientific Laboratory is the first operating example of a new class of pulsed neutron sources using the X(p,n)Y spallation reaction. At present, up to 10 microamperes of 800-MeV protons from the Clinton P. Anderson Meson Physics Facility (LAMPF) linear accelerator bombard a Ta target to produce an intense white-neutron spectrum from about 800 MeV to 100 keV. The Ta target can be coupled with CH 2 and H 2 O moderators to produce neutrons of lower energy. The time structure of the WNR proton beam may be varied to optimize neutron time-of-flight (TOF) measurements covering the energy range from several hundred MeV to a few meV. The neutronics of the WNR target and target/moderator configurations have been calculated from 800 MeV to 0.5 eV. About 11 neutrons per proton are predicted for the existing Ta target. Some initial neutron TOF data are presented and compared with calculations

  4. MEGAPIE spallation target: Design, manufacturing and preliminary tests of the first pro-typical spallation target for future ADS

    International Nuclear Information System (INIS)

    Latge, Ch.; Laffont, G.; Groeschel, F.; Thomsen, K.; Wagner, W.; Agostini, P.; Dierckx, M.; Fazio, C.; Kirchner, T.; Kurata, Y.; Song, T.; Woloshun, K.

    2006-01-01

    Partitioning and Transmutation (P and T) techniques could contribute to reduce the radioactive inventory and its associated radiotoxicity. Sub-critical Accelerator Driven Systems (ADS) are potential candidates as dedicated transmutation systems, and thus their development is a relevant R and D topic in Europe. Following a first phase focused on the understanding of the basic principles of ADS (e.g. the programme MUSE), the R and D has been streamlined and focused on practical demonstration key issues. These demonstrations cover high intensity proton accelerators (beam current in the range 1 to 20 mA), spallation targets of high power and their effective coupling with a subcritical core. Presently there is general consensus that up to 1 MW of beam power solid targets are feasible from a heat removal point of view. For higher power levels liquid metal targets are the option of choice because of their higher heat removal capability, higher spallation material density in the volume and lower specific radioactivity, Therefore, a key experiment in the ADS road map, the Megawatt Pilot Experiment (MEGAPIE) (1 MW) was initiated in 1999 in order to design and build a liquid lead-bismuth spallation target, then to operate it into the Swiss spallation neutron facility SINQ at Paul Scherrer Institute (PSI). It has to be equipped to provide the largest possible amount of scientific and technical information without jeopardizing its safe operation. The minimum design service life has been fixed at 1 year (6000 mAh). Whereas the interest of the partner institutes is driven by the development needs of ADS, PSI interest lies also in the potential use of a LM target as a SINQ standard target providing a higher neutron flux than the current solid targets. Calculations of the radial distribution of the undisturbed thermal neutron flux for the LBE target in comparison to the former Zircaloy and current steel-clad solid lead target were done with different nuclear codes; nevertheless

  5. Tool for the study of matter - the spallation neutron source. Werkzeug zur Erforschung der Materie - die Spallations-Neutronenquelle

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

    It deals with the optimal use of a whole series of matter penetrating radiation types at the construction of a spallation neutron source which the Kernforschungsanlage Juelich will realize in agreement with its associated. This new big science device for the fundamental research in the Federal Republic of Germany shall as the most modern and intense source of neutrons, protons, pions, muons, and neutrinos permits to proceed in the fields of solid state physics, chemistry, molecular biology, intermediate-energy nuclear physics, radiochemistry and radiopharmacology, medicine, and materials science to virgin territory and to provide top research. All interested German groups of researchers and also scientists of foreign countries shall be able to work with this directive big science device.

  6. A proposal for a long-pulse spallation source at Los Alamos National Laboratory

    International Nuclear Information System (INIS)

    Pynn, R.; Weinacht, D.

    1995-01-01

    Los Alamos National Laboratory is proposing a new spallation neutron source that will provide the US with an internationally competitive facility for neutron science and technology that can be built in approximately three years for less than $100 million. The establishment of a 1-MW, long-pulse spallation source (LPSS) at the Los Alamos Neutron Science Center (LANSCE) will meet many of the present needs of scientists in the neutron scattering community and provide a significant boost to neutron research in the US. The new facility will support the development of a future, more intense spallation neutron source, that is planned by DOE's Office of Energy Research. Together with the existing short pulse spallation source (SPSS) at the Manual Lujan, Jr. Neutron Scattering Center (MLNSC) at Los Alamos, the new LPSS will provide US scientists with a complementary pair of high-performance neutron sources to rival the world's leading facilities in Europe

  7. Electron cloud instabilities in the Proton Storage Ring and Spallation Neutron Source

    Directory of Open Access Journals (Sweden)

    M. Blaskiewicz

    2003-01-01

    Full Text Available Electron cloud instabilities in the Los Alamos Proton Storage Ring and those foreseen for the Oak Ridge Spallation Neutron Source are examined theoretically, numerically, and experimentally.

  8. Technology and science at a high-power spallation source: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    These proceedings cover many aspects of the usefulness of spallation neutrons. Nine different areas are considered: surfaces and interfaces, engineering, materials science, polymers and complex fluids, chemistry, structural biology, nuclear engineering and radiation effects, condensed matter physics and fundamental physics.

  9. Technology and science at a high-power spallation source: Proceedings

    International Nuclear Information System (INIS)

    1994-01-01

    These proceedings cover many aspects of the usefulness of spallation neutrons. Nine different areas are considered: surfaces and interfaces, engineering, materials science, polymers and complex fluids, chemistry, structural biology, nuclear engineering and radiation effects, condensed matter physics and fundamental physics

  10. Mercury purification in the megawatt liquid metal spallation target of EURISOL-DS

    CERN Document Server

    Neuhausen, Joerg; Eller, Martin; Schumann, Dorothea; Eichler, Bernd; Horn, Susanne

    High power spallation targets are going to be used extensively in future research and technical facilities such as spallation neutron sources, neutrino factories, radioactive beam facilities or accelerator driven systems for the transmutation of long-lived nuclear waste. Within EURISOL-DS, a 4 MW liquid metal spallation target is designed to provide neutrons for a fission target, where neutron rich radionuclides will be produced. For the spallation target, mercury is planned to be used as target material. A large amount of radionuclides ranging from atomic number Z=1 to 81 will be produced in the liquid metal during long term irradiation. It is planned to remove those radionuclides by chemical or physicochemical methods to reduce its radioactivity. For the development of a purification procedure, knowledge about the chemical state of the different elements present in the mixture is required. We present a general concept of applicable separation techniques in a target system and show some results of experiment...

  11. ELECTRON CLOUD AT COLLIMATOR AND INJECTION REGION OF THE SPALLATION NEUTRON SOURCE ACCUMULATOR RING

    International Nuclear Information System (INIS)

    WANG, L.; HSEUH, H.-C.; LEE, Y.Y.; RAPARIA, D.; WEI, J.; COUSINEAU, S.

    2005-01-01

    The beam loss along the Spallation Neutron Source's accumulator ring is mainly located at the collimator region and injection region. This paper studied the electron cloud build-up at these two regions with the three-dimension program CLOUDLAND

  12. A proposal for a long-pulse spallation source at Los Alamos National Laboratory

    International Nuclear Information System (INIS)

    Pynn, R.; Weinacht, D.

    1995-01-01

    Los Alamos National Laboratory is proposing a new spallation neutron source that will provide the U.S. with an internationally competitive facility for neutron science and technology that can be built in approximately three years for less than $100 million. The establishment of a 1-MW long-pulse spallation source (LPSS) at the Los Alamos Neutron Science Center (LANSCE) will meet many of the present needs of scientists in the neutron scattering community and provide a significant boost to neutron research in the U.S. The new facility will support the development of a future, more intense spallation neutron source, that is planned by DOE's Office of Energy Research. Together with the existing short pulse spallation source (SPSS) at the Manual Lujan, Jr. Neutron Scattering Center (MLNSC) at Los Alamos, the new LPSS will provide U.S. scientists with a complementary pair of high-performance neutron sources to rival the world's leading facilities in Europe. (author) 1 ref

  13. An attempt to analyse spallation yelds with a four-parameter formula

    International Nuclear Information System (INIS)

    Martins, J.B.; Napoli, V. di; Tavares, O.A.P.; Terranova, M.L.; Portanova, R.

    1978-09-01

    A semiempirical four-parameter formula, following the formalism of Gupta, is proposed in order to systematise spallation yields. A preliminary test made by comparing calculated and experimentally determined cross sections for 2-GeV bremsstrahlung-induced spallation in natural copper gave very encouraging results (a coefficient of reproducibility R = 1.7 or better). The formula will be used for an exhaustive study of intermediate- and high-energy photospallation of medium-weight nuclei [pt

  14. Big-bang nucleosynthesis with a long-lived CHAMP including He4 spallation process

    Science.gov (United States)

    Yamanaka, Masato; Jittoh, Toshifumi; Kohri, Kazunori; Koike, Masafumi; Sato, Joe; Sugai, Kenichi; Yazaki, Koichi

    2014-03-01

    We propose helium-4 spallation processes induced by long-lived stau in supersymmetric standard models, and investigate an impact of the processes on light elements abundances. We show that, as long as the phase space of helium-4 spallation processes is open, they are more important than stau-catalyzed fusion and hence constrain the stau property. This talk is based on the work of ref. [1].

  15. Licensing review process of the European Spallation Source (ESS) research facility

    International Nuclear Information System (INIS)

    Brewitz, Erica

    2014-01-01

    On 3 January 2012 a license application under the Radiation Protection Act (SFS, 1988b) for the European Spallation Source research facility was submitted to the Swedish Radiation Safety Authority. The European Spallation Source research facility will be the site of a new and quite unusual kind of neutron source, based on a large proton accelerator that bombards a heavy material with protons. The Swedish Radiation Safety Authority is now reviewing the application. (authors)

  16. Goldtraces on wedge-shaped artefacts from late neolithic of south Scandinavia analysed by proton induced x-ray emission spectroscopy

    International Nuclear Information System (INIS)

    Ahlberg, M.; Akselsson, R.; Forkman, B.; Rausing, G.

    1975-01-01

    Visible coloured traces on the surface of two selected wedge-shaped artefacts (pendants) of slate from the late Neolithic of South Scandinavia was analysed by means of proton-induced x-ray emission spectroscopy (PIXE). PIXE is shown to be a feasible tool in investigating surface layers of archeological significance. Three different gold-silver alloys was found on the two pendants. The results indicate that we shall have to reconsider the general accepted theories on the economic basis of the early Bronze Age in the area. (author)

  17. Determination of fluorine by proton induced gamma ray emission (PIGE) spectrometry in igneous and metamorphic charnockitic rocks from Rogaland (S.W. Norway)

    International Nuclear Information System (INIS)

    Roelandts, I.; Robaye, G.; Weber, G.; Delbrouck, J.M.; Duchesne, J.C.

    1986-01-01

    More than 200 specimens from different occurrences of the Rogaland igneous complex and surrounding granulite facies metamorphic rocks (S.W. Norway) have been analysed by a direct non-destructive proton induced gamma ray emission (PIGE) technique. The fluorine contents vary from < 25 ppm to 3500 ppm. There is a good correlation between the concentration of fluorine and that of phosphorus for igneous rocks, suggesting a control of apatite on the F content. In metamorphic rocks, amphibole and biotite besides apatite are the principal concentrations of fluorine indicating that fluorine in the system is controlled by granulite facies metamorphism conditions. (author)

  18. Comparison of the trace analysis of heavy metal aerosols by means of atom absorption spectroscopy and proton-induced X-ray spectrometry

    International Nuclear Information System (INIS)

    Nottrodt, K.H.; Georgii, H.W.; Groeneveld, K.O.; Frankfurt Univ.

    1977-01-01

    The comparative analyses of AAS and PIXE (Proton-Induced X-ray Emission) show very good agreement in the absolute values of the concentrations of all metals analyzed. The practical detection limits are about 10 -10 g for the investigated element in both measuring processes, so that the analysis of pure air samples is possible with both methods. PIXE is particularly suitable for the analysis of aerosol samples as it is not necessary to process the filter, the samples are not destroyed, and many elements can be simultaneously analyzed within a short time (5-10 min.). Furthermore, the possibility of automatization enables an efficient treatment of meteorological problems. (orig.) [de

  19. Implantation of the method of quantitative analysis by proton induced X-ray analysis and application to the analysis of aerosols

    International Nuclear Information System (INIS)

    Margulis, W.

    1977-09-01

    Fundamental aspects for the implementation of the method of quantitative analysis by proton induced X-ray spectroscopy are discussed. The calibration of the system was made by determining a response coefficient for selected elements, both by irradiating known amounts of these elements as well as by the use of theoretical and experimental parameters. The results obtained by these two methods agree within 5% for the analysed elements. A computer based technique of spectrum decomposition was developed to facilitate routine analysis. Finally, aerosol samples were measured as an example of a possible application of the method, and the results are discussed. (Author) [pt

  20. The determination of trace quantities of thorium and uranium in thick ore samples by proton-induced x-ray emission

    International Nuclear Information System (INIS)

    Cohen, D.D.; Duerden, P.; Clayton, E.

    1979-07-01

    Proton-induced X-ray emission (PIXE) techniques have been used to estimate the concentrations of trace quantities of thorium and uranium in powdered rock and ore samples. Standards of known concentrations were prepared in a carbon matrix and the yields from these used to determine simultaneously the concentrations of thorium and uranium in the ore samples. The experimental detection limit of the technique was found to be 3 to 4 μg g -1 for a 100 μC irradiation. The appropriate matrix corrections for a carbon and ore matrix have been calculated for thick targets and taken into consideration

  1. Cooperative effort between Consorcio European Spallation Source--Bilbao and Oak Ridge National Laboratory spallation neutron source for manufacturing and testing of the JEMA-designed modulator system

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, David E [ORNL

    2017-01-02

    The JEMA modulator was originally developed for the European Spallation Source (ESS) when Spain was under consideration as a location for the ESS facility. Discussions ensued and the Spallation Neutron Source Research Accelerator Division agreed to form a collaboration with ESS-Bilbao (ESS-B) consortium to provide services for specifying the requirements for a version of the modulator capable of operating twelve 550 kW klystrons, monitoring the technical progress on the contract with JEMA, installing and commissioning the modulator at SNS, and performing a 30 day full power test. This work was recently completed, and this report discusses those activities with primary emphasis on the installation and testing activities.

  2. Cooperative effort between Consorcio European Spallation Source--Bilbao and Oak Ridge National Laboratory spallation neutron source for manufacturing and testing of the JEMA-designed modulator system

    International Nuclear Information System (INIS)

    Anderson, David E.

    2017-01-01

    The JEMA modulator was originally developed for the European Spallation Source (ESS) when Spain was under consideration as a location for the ESS facility. Discussions ensued and the Spallation Neutron Source Research Accelerator Division agreed to form a collaboration with ESS-Bilbao (ESS-B) consortium to provide services for specifying the requirements for a version of the modulator capable of operating twelve 550 kW klystrons, monitoring the technical progress on the contract with JEMA, installing and commissioning the modulator at SNS, and performing a 30 day full power test. This work was recently completed, and this report discusses those activities with primary emphasis on the installation and testing activities.

  3. Safety techniques in the change of nuclear systems. Radiation protection at spallation neutron sources and transmutation facilities

    International Nuclear Information System (INIS)

    Nuenighoff, Kay

    2009-01-01

    To push the boundary towards higher neutron fluxes concepts based on spallation reactions have been discussed. Here neutrons are produced by bombarding a heavy metal target (e.g. mercury, tungsten, or tantalum) with high energetic protons. Up to now such facilities could not be realised because of the high power particle accelerators needed. Recent developments of the accelerator technology open the possibility of construction and operating proton accelerators in the MW region. This is demonstrated by construction and commissioning of two MW spallation neutron sources, namely SNS (Oak Ridge, Tennessee, USA) with a power of 1.4 MW and J-PARC (Japan) with 1 MW. The realisation of proton accelerators at this power level will open the way towards energy amplifiers, as proposed e.g. by Carlo Rubbia. Such a facility will not only produce electric power. Furthermore longliving radionuclides can be transmutated into shortlived or even stable nuclides by neutron induced nuclear reactions. A mitigation of the problem of nuclear waste disposal. The above discussed developments prove that accelerators are not only constructed for research, moreover application of these technology became state of the art. With the emergence of particle accelerators in the MW region, radiation protection is confronted with new kind of problems to be solved. Especially the higher kinetic energies of the primary beam particles requires modification and expansion of computer programs well known in nuclear engineering. In contrast to nuclear reactors with kinetic energies up to 2-3 MeV, in spallation reaction secondary particles up to the incident energy in the GeV region will be produced. Problems related to radiation protection have to be considered in an energy range three orders of magnitude higher than known from nuclear reactors. In this thesis existing computer codes are compared and validated with data from selected experiments. Questions concerning radiation protection covers a broad range

  4. On spallation and fragmentation of heavy ions at intermediate energies

    International Nuclear Information System (INIS)

    Musulmanbekov, G.; Al-Haidary, A.

    2002-01-01

    A new code for simulation of spallation and (multi)fragmentation of nuclei in proton and nucleus induced collisions at intermediate and high energies is developed. The code is a combination of modified intranuclear cascade model with traditional fission - evaporation part and multifragmentation part based on lattice representation of nuclear structure and percolation approach. The production of s-wave resonances and formation time concept included into standard intranuclear cascade code provides correct calculation of excitation energy of residues. This modified cascade code served as a bridge between low and high energy model descriptions of nucleus-nucleus collisions. A good agreement with experiments has been obtained for multiparticle production at intermediate and relatively high energies. Nuclear structure of colliding nuclei is represented as face centered cubic lattice. This representation, being isomorphic to the shell model of nuclear structure, allows to apply percolation approach for nuclear fragmentation. The offered percolation model includes both site and bond percolation. Broken sites represent holes left by nucleons knocked out at cascade state. Therefore, in the first cascade stage mutual rescattering of the colliding nuclei results in knocking some nucleons out of them. After this fast stage paltrily destruct and excited residues remain. On the second stage residual nuclei either evaporate nucleons and light nuclei up to alpha-particles or fragment into pieces with intermediate masses. The choice depends on residue's destruction degree. At low excitation energy and small destruction of the residue the evaporation and fission mechanisms are preferable. The more excitation energy and destruction the more probability of (multi)fragmentation process. Moreover, the more destruction degree of the residual the more the site percolation probability. It is concluded, that at low and intermediate excitation energies the fragmentation of nuclei is slow

  5. Device for Writing the Time Tail from Spallation Neutron Pulses

    International Nuclear Information System (INIS)

    Langan, P.; Schoenborn, Benno P.; Daemen, L.L.

    2001-01-01

    Recent work at Los Alamos Neutron Science Center (LANSCE), has shown that there are large gains in neutron beam intensity to be made by using coupled moderators at spallation neutron sources. Most of these gains result from broadening the pulse-width in time. However the accompanying longer exponential tail at large emission times can be a problem in that it introduces relatively large beam-related backgrounds at high resolutions. We have designed a device that can reshape the moderated neutron beam by cutting the time-tail so that a sharp time resolution can be re-established without a significant loss in intensity. In this work the basic principles behind the tail-cutter and some initial results of Monte Carlo simulations are described. Unwanted neutrons in the long time-tail are diffracted out of the transmitted neutron beam by a nested stack of aperiodic multi-layers, rocking at the same frequency as the source. Nested aperiodic multi-layers have recently been used at X-ray sources and as band-pass filters in quasi-Laue neutron experiments at reactor neutron sources. Optical devices that rock in synchronization with a pulsed neutron beam are relatively new but are already under construction at LANSCE. The tail-cutter described here is a novel concept that uses existing multi-layer technology in a new way for spallation neutrons. Coupled moderators in combination with beam shaping devices offer the means of increasing flux whilst maintaining a sharp time distribution. A prototype device is being constructed for the protein crystallography station at LANSCE. The protein crystallography station incorporates a water moderator that has been judiciously coupled in order to increase the flux over neutron energies that are important to structural biology (3-80meV). This development in moderator design is particularly important because protein crystallography is flux limited and because conventional ambient water and cold hydrogen moderators do not provide relatively

  6. Mechanical Engineering of the Linac for the Spallation Neutron Source

    International Nuclear Information System (INIS)

    Bultman, N.K.; Chen, Z.; Collier, M.; Erickson, J.L.; Guthrie, A.; Hunter, W.T.; Ilg, T.; Meyer, R.K.; Snodgrass, N.L.

    1999-01-01

    The linac for the Spallation Neutron Source (SNS) Project will accelerate an average current of 1 mA of H - ions from 20 MeV to 1GeV for injection into an accumulator ring. The linac will be an intense source of H - ions and as such requires advanced design techniques to meet project technical goals as well as to minimize costs. The DTL, CCDTL and CCL are 466m long and operate at 805 MHz with a maximum H - input current of 28 mA and 7% rf duty factor. The Drift Tube Linac is a copper-plated steel structure using permanent magnetic quadrupoles. The Coupled-Cavity portions are brazed copper structures and use electromagnetic quads. RF losses in the copper are 80 MW, with total rf power supplied by 52 klystrons. Additionally, the linac is to be upgraded to the 2- and 4-MW beam power levels with no increase in duty factor. The authors give an overview of the linac mechanical engineering effort and discuss the special challenges and status of the effort

  7. Feasibility study for the spallation neutron source (SNQ). Pt. 1

    International Nuclear Information System (INIS)

    Bauer, G.S.; Sebening, H.; Vetter, J.E.; Willax, H.

    1981-06-01

    A concept for a new neutron source for fundamental research has been developed and is described in this report. The spallation neutron source SNQ is characterized in its first stage by a time average thermal neutron flux of 7 x 10 14 cm -2 s -1 and a peak flux of 1.3 x 10 16 cm -2 s -1 at 100 Hz repetition rate. The scientific case is presented with particular emphasis on solid state and nuclear physics. In these research domains, unique conditions are given for experimental use. The proposed machine consists in its basic stage of a 1.1 GeV, 5 mA time average, 100 mA peak current proton linear accelerator, a rotating lead target, and H 2 O and D 2 O moderators. Additional beam channels are provided for experiments with protons at 350 MeV and at the final energy. Construction of the SNQ is considered feasible within eight years at a cost of 680 million DM. As future options, use of uranium as a target material, increase of the accelerator beam power by a factor of 2, addition of a pulse compressor and a second target station for pulsed neutron and neutrino research are described. As a back-up solution to the rotating target, a liquid metal target was studied. (orig.) [de

  8. Neutron diffractometers for structural biology at spallation neutron sources

    Energy Technology Data Exchange (ETDEWEB)

    Schoenborn, B.P.; Pitcher, E. [Los Alamos National Laboratory, NM (United States)

    1994-12-31

    Spallation neutron sources are ideal for diffraction studies of proteins and oriented molecular complexes. With spoliation neutrons and their time dependent wavelength structure, it is easy to electronically select data with an optimal wavelength bandwidth and cover the whole Laue spectrum as time (wavelength) resolved snapshots. This optimized data quality with best peak-to-background ratios and provides adequate spatial and energy resolution to eliminate peak overlaps. The application of this concept will use choppers to select the desired Laue wavelength spectrum and employ focusing optics and large cylindrical {sup 3}He detectors to optimize data collection rates. Such a diffractometer will cover a Laue wavelength range from 1 to 5{Angstrom} with a flight path length of 10m and an energy resolution of 0.25{Angstrom}. Moderator concepts for maximal flux distribution within this energy range will be discussed using calculated flux profiles. Since the energy resolution required for such timed data collection in this super Laue techniques is not very high, the use of a linac only (LAMPF) spoliation target is an exciting possibility with an order of magnitude increase in flux.

  9. Engineering design of the EURISOL multi-MW spallation target

    CERN Document Server

    Herrera-Martínez, A; Ashrafi-Nik, M; Samec, K; Freibergs, J; Platacis, E

    2007-01-01

    The European Isotope Separation On-Line Radioactive Ion Beam project (EURISOL) is set to design the 'next-generation' European Isotope Separation On-Line (ISOL) Radioactive Ion Beam (RIB) facility. It will extend and amplify current research on nuclear physics, nuclear astrophysics and fundamental interactions beyond the year 2010. In EURISOL, four target stations are foreseen, three direct targets of approximately 100 kW of beam power and one multi-MW target assembly, all driven by a high-power particle accelerator. In this high power target station, high-intensity RIBs of neutron-rich isotopes will be obtained by inducing fission in several actinide targets surrounding a liquid metal spallation neutron source. This article summarises the work carried out within Task 2 of the EURISOL Design Study, with special attention to the coupled neutronics of the mercury proton-to-neutron converter and the fission targets. The overall performance of the facility, which will sustain fast neutron fluxes of the order of 1...

  10. ENGINEERING DESIGN OF THE EURISOL MULTI-MW SPALLATION TARGET

    CERN Document Server

    Adonai Herrera-Martinez*, Yacine Kadi, Morteza Ashrafi-Nik, Karel Samec, Janis Freibergs, Ernests Platacis

    The European Isotope Separation On-Line Radioactive Ion Beam project (EURISOL) is set to design the ‘next-generation’ European Isotope Separation On-Line (ISOL) Radioactive Ion Beam (RIB) facility. It will extend and amplify current research on nuclear physics, nuclear astrophysics and fundamental interactions beyond the year 2010. In EURISOL, four target stations are foreseen, three direct targets of approximately 100 kW of beam power and one multi-MW target assembly, all driven by a high-power particle accelerator. In this high power target station, high-intensity RIBs of neutron-rich isotopes will be obtained by inducing fission in several actinide targets surrounding a liquid metal spallation neutron source. This article summarises the work carried out within Task 2 of the EURISOL Design Study, with special attention to the coupled neutronics of the mercury proton-to-neutron converter and the fission targets. The overall performance of the facility, which will sustain fast neutron fluxes of the order ...

  11. Spallation Neutron Source Accident Terms for Environmental Impact Statement Input

    Energy Technology Data Exchange (ETDEWEB)

    Devore, J.R.; Harrington, R.M.

    1998-08-01

    This report is about accidents with the potential to release radioactive materials into the environment surrounding the Spallation Neutron Source (SNS). As shown in Chap. 2, the inventories of radioactivity at the SNS are dominated by the target facility. Source terms for a wide range of target facility accidents, from anticipated events to worst-case beyond-design-basis events, are provided in Chaps. 3 and 4. The most important criterion applied to these accident source terms is that they should not underestimate potential release. Therefore, conservative methodology was employed for the release estimates. Although the source terms are very conservative, excessive conservatism has been avoided by basing the releases on physical principles. Since it is envisioned that the SNS facility may eventually (after about 10 years) be expanded and modified to support a 4-MW proton beam operational capability, the source terms estimated in this report are applicable to a 4-MW operating proton beam power unless otherwise specified. This is bounding with regard to the 1-MW facility that will be built and operated initially. See further discussion below in Sect. 1.2.

  12. Spallation neutron source target design for radioactive waste transmutation

    International Nuclear Information System (INIS)

    Beard, C.A.

    1992-01-01

    The disposal of high-level radioactive waste has long been one of the most serious problems facing the nuclear industry. Transmutation of this waste through particle bombardment has been suggested numerous times as a possible method of enhancing the waste management process. Due to advances in accelerator technology, the feasibility of an accelerator based transmutation system has increased enough to allow serious investigation of this process. Therefore, in pursuit of this goal, an accelerator target was designed for use in an accelerator based transmutation system. The target design consists of an array of tantalum rods, cooled by liquid sodium, which are arranged in a cylindrical configuration 40 cm in diameter and 125 cm in height. Tantalum was chosen as the target material over tungsten, lead, bismuth, and a lead-bismuth alloy (55 w/o bismuth) due to a large neutron yield, low activation, low chemical toxicity, and the fact that it does not produce significant amounts of long-lived isotopes through spallation or activation. The target yields a neutron source of 29.7 neutrons/proton when exposed to a 1600 MeV proton beam, and is suitable for use with both thermal or fast spectrum transmutation systems

  13. Beam dynamics simulation of the Spallation Neutron Source linear accelerator

    International Nuclear Information System (INIS)

    Takeda, H.; Billen, J.H.; Bhatia, T.S.

    1998-01-01

    The accelerating structure for Spallation Neutron Source (SNS) consists of a radio-frequency-quadrupole-linac (RFQ), a drift-tube-linac (DTL), a coupled-cavity-drift-tube-linac (CCDTL), and a coupled-cavity-linac (CCL). The linac is operated at room temperature. The authors discuss the detailed design of linac which accelerates an H - pulsed beam coming out from RFQ at 2.5 MeV to 1000 MeV. They show a detailed transition from 402.5 MHz DTL with a 4 βλ structure to a CCDTL operated at 805 MHz with a 12 βλ structure. After a discussion of overall feature of the linac, they present an end-to-end particle simulation using the new version of the PARMILA code for a beam starting from the RFQ entrance through the rest of the linac. At 1000 MeV, the beam is transported to a storage ring. The storage ring requires a large (±500-keV) energy spread. This is accomplished by operating the rf-phase in the last section of the linac so the particles are at the unstable fixed point of the separatrix. They present zero-current phase advance, beam size, and beam emittance along the entire linac

  14. Reliability model of SNS linac (spallation neutron source-ORNL)

    International Nuclear Information System (INIS)

    Pitigoi, A.; Fernandez, P.

    2015-01-01

    A reliability model of SNS LINAC (Spallation Neutron Source at Oak Ridge National Laboratory) has been developed using risk spectrum reliability analysis software and the analysis of the accelerator system's reliability has been performed. The analysis results have been evaluated by comparing them with the SNS operational data. This paper presents the main results and conclusions focusing on the definition of design weaknesses and provides recommendations to improve reliability of the MYRRHA ( linear accelerator. The reliability results show that the most affected SNS LINAC parts/systems are: 1) SCL (superconducting linac), front-end systems: IS, LEBT (low-energy beam transport line), MEBT (medium-energy beam transport line), diagnostics and controls; 2) RF systems (especially the SCL RF system); 3) power supplies and PS controllers. These results are in line with the records in the SNS logbook. The reliability issue that needs to be enforced in the linac design is the redundancy of the systems, subsystems and components most affected by failures. For compensation purposes, there is a need for intelligent fail-over redundancy implementation in controllers. Enough diagnostics has to be implemented to allow reliable functioning of the redundant solutions and to ensure the compensation function

  15. Feasibility study of a 1-MW pulsed spallation source

    International Nuclear Information System (INIS)

    Cho, Y.; Chae, Y.C.; Crosbie, E.

    1995-01-01

    A feasibility study of a 1-MW pulsed spallation source based on a rapidly cycling proton synchrotron (RCS) has been completed. The facility consists of a 400-MeV HP - linac, a 30-Hz RCS that accelerates the 400-MeV beam to 2 GeV, and two neutron-generating target stations. The design time-averaged current of the accelerator system is 0.5 mA, or 1.04x1014 protons per pulse. The linac system consists of an H - ion source, a 2-MeV RFQ, a 70-MeV DTL and a 330-MeV CCL. Transverse phase space painting to achieve a Kapchinskij-Vladimirskij (K-V) distribution of the injected particles in the RCS is accomplished by charge exchange injection and programming of the closed orbit during injection. The synchrotron lattice uses FODO cells of ∼90 degrees phase advance. Dispersion-free straight sections are obtained by using a missing magnet scheme. Synchrotron magnets are powered by a dual-frequency resonant circuit that excites the magnets at a 20-Hz rate and de-excites them at a 60-Hz rate, resulting in an effective rate of 30 Hz, and reducing the required peak rf voltage by 1/3. A key feature, of the design of this accelerator system is that beam losses are from injection to extraction, reducing activation to levels consistent with hands-on maintenance. Details of the study are presented

  16. Neutron diffractometers for structural biology at spallation neutron sources

    International Nuclear Information System (INIS)

    Schoenborn, B.P.; Pitcher, E.

    1994-01-01

    Spallation neutron sources are ideal for diffraction studies of proteins and oriented molecular complexes. With spoliation neutrons and their time dependent wavelength structure, it is easy to electronically select data with an optimal wavelength bandwidth and cover the whole Laue spectrum as time (wavelength) resolved snapshots. This optimized data quality with best peak-to-background ratios and provides adequate spatial and energy resolution to eliminate peak overlaps. The application of this concept will use choppers to select the desired Laue wavelength spectrum and employ focusing optics and large cylindrical 3 He detectors to optimize data collection rates. Such a diffractometer will cover a Laue wavelength range from 1 to 5 Angstrom with a flight path length of 10m and an energy resolution of 0.25 Angstrom. Moderator concepts for maximal flux distribution within this energy range will be discussed using calculated flux profiles. Since the energy resolution required for such timed data collection in this super Laue techniques is not very high, the use of a linac only (LAMPF) spoliation target is an exciting possibility with an order of magnitude increase in flux

  17. Cold moderators at pulsed spallation sources: A personal view

    International Nuclear Information System (INIS)

    Pynn, R.

    1991-01-01

    When Maier-Leibnitz built the ILL, he came first to the US and to Canada where there were several prominent neutron scattering centers. He asked what instruments he should build. The reply was unanimous: 'First you build some three-axis machines to form the base program and then you see what else you can thin of.' Maier-Leibnitz's reply was equally characteristic: 'Thank you very much hor-ellipsis there will be no three-axis spectrometers at my institute.' He wasn't quite right - there was one at the beginning. But the point is that, instead of following conventional wisdom, Maier-Leibnitz hired a bunch of young scientists who didn't know as much about neutron scattering as their colleagues on the American continent and who therefore did not know what was 'impossible.' So, they built the impossible - a cold source integrated into the reactor, several hundred meters of guides, a 40-meter SANS machine, a back-scattering spectrometer, a hedgehog - the whole works. And they changed the face of neutron scattering forever. The author is going to adopt the same philosophy - because he knows very little about cold moderators at spallation sources, he doesn't know what is possible or what is stupid. So he is going to make some outrageous comments to stimulate Peter Egelstaff's discussion session. He makes these remarks, not as Director of LANSCE, but as a research scientist looking well beyond his ares of expertise

  18. Spallative production of Li, Be and B in superbubbles

    Science.gov (United States)

    Parizot, Etienne

    We investigate the spallative production of the light elements (Li, Be and B) associated with the evolution of a superbubble (SB) blown by repeated supernova explosions in an OB association. It is shown that if about ten percent of the SN energy can power the acceleration of particles from the material inside the SB, the observed abundances of LiBeB in halo stars, as a function of O, can be explained in a fully consistent way over several decades of metallicity. We investigate two different energy spectra for the EPs: the standard cosmic ray source spectrum and a specific `SB spectrum' as results from Bykov's SB acceleration mechanism. We find that the latter spectrum is more efficient in producing LiBeB, and that the SNR spectrum can be reconciled with the observational data if an imperfect mixing of the SN ejecta with the rest of the SB material and/or a selective acceleration is invoked (enhancing the C and O abundance amongst the EPs by a factor of ˜ 6). One consequence of the model is that the observed linear growth of Be and B abundances as a function of the metallicity expresses a dilution line rather than a continuous, monotonic increase throughout the Galaxy. We also find that the recent 6 Li observations in halo stars fit equally well in the framework of the SB model (see Parizot & Drury, 1999c, for more details).

  19. Spallation Neutron Source Second Target Station Integrated Systems Update

    Energy Technology Data Exchange (ETDEWEB)

    Ankner, John Francis [ORNL; An, Ke [ORNL; Blokland, Willem [ORNL; Charlton, Timothy R. [ORNL; Coates, Leighton [ORNL; Dayton, Michael J. [ORNL; Dean, Robert A. [ORNL; Dominguez-Ontiveros, Elvis E. [ORNL; Ehlers, Georg [ORNL; Gallmeier, Franz X. [ORNL; Graves, Van B. [ORNL; Heller, William T. [ORNL; Holmes, Jeffrey A. [ORNL; Huq, Ashfia [ORNL; Lumsden, Mark D. [ORNL; McHargue, William M. [ORNL; McManamy, Thomas J. [ORNL; Plum, Michael A. [ORNL; Rajic, Slobodan [ORNL; Remec, Igor [ORNL; Robertson, Lee [ORNL; Sala, Gabriele [ORNL; Stoica, Alexandru Dan [ORNL; Trotter, Steven M. [ORNL; Winn, Barry L. [ORNL; Abudureyimu, Reheman [ORNL; Rennich, Mark J. [ORNL; Herwig, Kenneth W. [ORNL

    2017-04-01

    The Spallation Neutron Source (SNS) was designed from the beginning to accommodate both an accelerator upgrade to increase the proton power and a second target station (STS). Four workshops were organized in 2013 and 2014 to identify key science areas and challenges where neutrons will play a vital role [1-4]. Participants concluded that the addition of STS to the existing ORNL neutron sources was needed to complement the strengths of High Flux Isotope Reactor (HFIR) and the SNS first target station (FTS). To address the capability gaps identified in the workshops, a study was undertaken to identify instrument concepts that could provide the required new science capabilities. The study outlined 22 instrument concepts and presented an initial science case for STS [5]. These instrument concepts formed the basis of a planning suite of instruments whose requirements determined an initial site layout and moderator selection. An STS Technical Design Report (TDR) documented the STS concept based on those choices [6]. Since issue of the TDR, the STS concept has significantly matured as described in this document.

  20. Spallation Neutron Source High Power RF Installation and Commissioning Progress

    CERN Document Server

    McCarthy, Michael P; Bradley, Joseph T; Fuja, Ray E; Gurd, Pamela; Hardek, Thomas; Kang, Yoon W; Rees, Daniel; Roybal, William; Young, Karen A

    2005-01-01

    The Spallation Neutron Source (SNS) linac will provide a 1 GeV proton beam for injection into the accumulator ring. In the normal conducting (NC) section of this linac, the Radio Frequency Quadupole (RFQ) and six drift tube linac (DTL) tanks are powered by seven 2.5 MW, 402.5 MHz klystrons and the four coupled cavity linac (CCL) cavities are powered by four 5.0 MW, 805 MHz klystrons. Eighty-one 550 kW, 805 MHz klystrons each drive a single cavity in the superconducting (SC) section of the linac. The high power radio frequency (HPRF) equipment was specified and procured by LANL and tested before delivery to ensure a smooth transition from installation to commissioning. Installation of RF equipment to support klystron operation in the 350-meter long klystron gallery started in June 2002. The final klystron was set in place in September 2004. Presently, all RF stations have been installed and high power testing has been completed. This paper reviews the progression of the installation and testing of the HPRF Sys...

  1. Commissioning of cryogenic system for China Spallation Neutron Source

    Science.gov (United States)

    Ye, Bin; He, Chongchao; Li, Na; Ding, Meiying; Wang, Yaqiong; Yu, Zhang; He, Kun

    2017-12-01

    China Spallation Neutron Source(CSNS) cryogenic system provides supercritical cryogenic hydrogen to neutron moderators, including a helium refrigerator, hydrogen loop and hydrogen safety equipment. The helium refrigerator is provided by Linde with cooling capacity of 2200 W at 20 K. Hydrogen loop system mainly includes cryogenic hydrogen pipes, hydrogen circulator cold-box and accumulator cold-box. Cryogenic hydrogen pump, ortho-para convertor, helium-hydrogen heat-exchanger, hydrogen heater and accumulator are integrated in hydrogen circulation cold-box, and accumulator cold-box. Hydrogen safety equipment includes safety valves, rupture disk, hydrogen sensor, flame detector and other equipment to ensure that cryogenic system in dangerous situations will go down, vents, or takes other measures. The cryogenic system commissioning work includes four steps. First, in order to test the refrigerating capacity of refrigerator, when acceptance testing, refrigerator internal heater was used as thermal load. Second, using simulation load as heat load of moderator, hydrogen loop use helium instead of hydrogen, and cooled down to 20 K, then re-warming and test the leak detection of hydrogen loop system. Third, base on the step 2, using hydrogen as working medium, and optimized the control logic. Forth, cryogenic system with the moderators joint commissioning. Now, cryogenic system is connected with the moderators, and the forth step will be carried out in the near future.

  2. Transmutation of 126Sn in spallation targets of accelerator-driven systems

    International Nuclear Information System (INIS)

    Han, Chi Young; Saito, Masaki; Sagara, Hiroshi

    2009-01-01

    The practical feasibility of 126 Sn transmutation in spallation targets of accelerator-driven systems was evaluated from the viewpoints of accumulation of radioactive spallation products and neutron production as well as transmutation amount of 126 Sn. A cylindrical liquid 126 Sn target whose length depends on proton beam energy was described, based on a Pb-Bi target design of accelerator-driven system being developed in JAEA. A proton beam of 1.5 GeV-20 mA was estimated to give the transmutation rate of 126 Sn 6.4 kg/yr, which corresponds to the amount of 126 Sn annually discharged in 27 LWRs of 1 GWt and 33 GWd/THM. The equilibrium radioactivity of spallation products would reach 9% of that of 126 Sn transmuted in the spallation target, and the equilibrium toxicity would be just 3%. Some parametric analyses showed that the effective half-life of 126 Sn could be reduced through a proper reduction of the target size. The 126 Sn target was calculated to produce 40 neutrons per proton of 1.5 GeV and give a neutron spectrum very similar to that of the reference Pb-Bi target. As a result, the transmutation of 126 Sn in the spallation target has a high feasibility in terms of better transmutation performance and comparable target performance. (author)

  3. Los Alamos pulsed spallation neutron source target systems - present and future

    International Nuclear Information System (INIS)

    Russell, G.J.; Daemen, L.L.; Pitcher, E.J.; Brun, T.O.; Hjelm, R.P. Jr.

    1993-01-01

    For the past 16 yr, spallation target-system designers have devoted much time and effort to the design and optimization of pulsed spallation neutron sources. Many concepts have been proposed, but, in practice, only one has been implemented horizontal beam insertion with moderators in wing geometry i.e., until we introduced the innovative split-target/flux-trap-moderator design with a composite reflector shield at the Manuel Lujan, Jr., Neutron Scattering Center (LANSCE). The LANSCE target system design is now considered a classic by spallation target system designers worldwide. LANSCE, a state-of-the-art pulsed spallation neutron source for materials science and nuclear physics research, uses 800-MeV protons from the Clinton P. Anderson Meson Physics Facility. These protons are fed into the proton storage ring to be compressed to 250-ns pulses before being delivered to LANSCE at 20 Hz. LANSCE produces the highest peak neutron flux of any pulsed spallation neutron source in the world

  4. Preparation and testing of corrosion and spallation-resistant coatings

    Energy Technology Data Exchange (ETDEWEB)

    Hurley, John P. [Univ. of North Dakota, Grand Forks, ND (United States); Cavalli, Matthew N. [Univ. of North Dakota, Grand Forks, ND (United States)

    2016-06-30

    its standard oxidation, spallation, and corrosion testing, which was scheduled for completion in the spring of 2016. However, because of commercial demands, the tests were not completed by the time of this report except some initial spallation tests at 1150°C. In those tests, several of the APMT plates separated from the CM247LC, likely because of the remaining aluminum oxide scale on the surface of the CM247LC. This implies that surface preparation may need to include machining to remove the oxide scale before bonding rather than just sandblasting. In previous tensile testing at 950°C, the breaks in the tensile samples always occurred in the APMT and not at the joints. Gasifier sampling was completed to determine what types of trace contaminants may occur in cleaned and combusted syngas and that could lead to corrosion or deposition in turbines firing coal syngas. The sampling was done from a pressurized fluidized-bed gasifier and a pressurized entrained-flow gasifier. The particles captured on a filter from syngas were typically 0.2 to 0.5 μm in diameter, whereas those captured from the combusted syngas were slightly larger and more spherical. X-ray photoelectron spectroscopy done at Oak Ridge National Laboratory showed that the particles do not contain any metals and have an atomic composition almost identical to that of the polycarbonate filter. This indicates that the particles are primarily soot-based and not formed from volatilization of metals in the gasifiers.

  5. The COHERENT Experiment at the Spallation Neutron Source

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Steven Ray [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

    2015-09-30

    The COHERENT collaboration's primary objective is to measure coherent elastic neutrino- nucleus scattering (CEvNS) using the unique, high-quality source of tens-of-MeV neutrinos provided by the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL). In spite of its large cross section, the CEvNS process has never been observed, due to tiny energies of the resulting nuclear recoils which are out of reach for standard neutrino detectors. The measurement of CEvNS has now become feasible, thanks to the development of ultra-sensitive technology for rare decay and weakly-interacting massive particle (dark matter) searches. The CEvNS cross section is cleanly predicted in the standard model; hence its measurement provides a standard model test. It is relevant for supernova physics and supernova-neutrino detection, and enables validation of dark-matter detector background and detector-response models. In the long term, precision measurement of CEvNS will address questions of nuclear structure. COHERENT will deploy multiple detector technologies in a phased approach: a 14-kg CsI[Na] scintillating crystal, 15 kg of p-type point-contact germanium detectors, and 100 kg of liquid xenon in a two-phase time projection chamber. Following an extensive background measurement campaign, a location in the SNS basement has proven to be neutron-quiet and suitable for deployment of the COHERENT detector suite. The simultaneous deployment of the three COHERENT detector subsystems will test the N=2 dependence of the cross section and ensure an unambiguous discovery of CEvNS. This document describes concisely the COHERENT physics motivations, sensitivity and plans for measurements at the SNS to be accomplished on a four-year timescale.

  6. 5 MW pulsed spallation neutron source, Preconceptual design study

    Energy Technology Data Exchange (ETDEWEB)

    1994-06-01

    This report describes a self-consistent base line design for a 5 MW Pulsed Spallation Neutron Source (PSNS). It is intended to establish feasibility of design and as a basis for further expanded and detailed studies. It may also serve as a basis for establishing project cost (30% accuracy) in order to intercompare competing designs for a PSNS not only on the basis of technical feasibility and technical merit but also on the basis of projected total cost. The accelerator design considered here is based on the objective of a pulsed neutron source obtained by means of a pulsed proton beam with average beam power of 5 MW, in {approx} 1 {mu}sec pulses, operating at a repetition rate of 60 Hz. Two target stations are incorporated in the basic facility: one for operation at 10 Hz for long-wavelength instruments, and one operating at 50 Hz for instruments utilizing thermal neutrons. The design approach for the proton accelerator is to use a low energy linear accelerator (at 0.6 GeV), operating at 60 Hz, in tandem with two fast cycling booster synchrotrons (at 3.6 GeV), operating at 30 Hz. It is assumed here that considerations of cost and overall system reliability may favor the present design approach over the alternative approach pursued elsewhere, whereby use is made of a high energy linear accelerator in conjunction with a dc accumulation ring. With the knowledge that this alternative design is under active development, it was deliberately decided to favor here the low energy linac-fast cycling booster approach. Clearly, the present design, as developed here, must be carried to the full conceptual design stage in order to facilitate a meaningful technology and cost comparison with alternative designs.

  7. 5 MW pulsed spallation neutron source, Preconceptual design study

    International Nuclear Information System (INIS)

    1994-06-01

    This report describes a self-consistent base line design for a 5 MW Pulsed Spallation Neutron Source (PSNS). It is intended to establish feasibility of design and as a basis for further expanded and detailed studies. It may also serve as a basis for establishing project cost (30% accuracy) in order to intercompare competing designs for a PSNS not only on the basis of technical feasibility and technical merit but also on the basis of projected total cost. The accelerator design considered here is based on the objective of a pulsed neutron source obtained by means of a pulsed proton beam with average beam power of 5 MW, in ∼ 1 μsec pulses, operating at a repetition rate of 60 Hz. Two target stations are incorporated in the basic facility: one for operation at 10 Hz for long-wavelength instruments, and one operating at 50 Hz for instruments utilizing thermal neutrons. The design approach for the proton accelerator is to use a low energy linear accelerator (at 0.6 GeV), operating at 60 Hz, in tandem with two fast cycling booster synchrotrons (at 3.6 GeV), operating at 30 Hz. It is assumed here that considerations of cost and overall system reliability may favor the present design approach over the alternative approach pursued elsewhere, whereby use is made of a high energy linear accelerator in conjunction with a dc accumulation ring. With the knowledge that this alternative design is under active development, it was deliberately decided to favor here the low energy linac-fast cycling booster approach. Clearly, the present design, as developed here, must be carried to the full conceptual design stage in order to facilitate a meaningful technology and cost comparison with alternative designs

  8. H- radio frequency source development at the Spallation Neutron Source.

    Science.gov (United States)

    Welton, R F; Dudnikov, V G; Gawne, K R; Han, B X; Murray, S N; Pennisi, T R; Roseberry, R T; Santana, M; Stockli, M P; Turvey, M W

    2012-02-01

    The Spallation Neutron Source (SNS) now routinely operates nearly 1 MW of beam power on target with a highly persistent ∼38 mA peak current in the linac and an availability of ∼90%. H(-) beam pulses (∼1 ms, 60 Hz) are produced by a Cs-enhanced, multicusp ion source closely coupled with an electrostatic low energy beam transport (LEBT), which focuses the 65 kV beam into a radio frequency quadrupole accelerator. The source plasma is generated by RF excitation (2 MHz, ∼60 kW) of a copper antenna that has been encased with a thickness of ∼0.7 mm of porcelain enamel and immersed into the plasma chamber. The ion source and LEBT normally have a combined availability of ∼99%. Recent increases in duty-factor and RF power have made antenna failures a leading cause of downtime. This report first identifies the physical mechanism of antenna failure from a statistical inspection of ∼75 antennas which ran at the SNS, scanning electron microscopy studies of antenna surface, and cross sectional cuts and analysis of calorimetric heating measurements. Failure mitigation efforts are then described which include modifying the antenna geometry and our acceptance∕installation criteria. Progress and status of the development of the SNS external antenna source, a long-term solution to the internal antenna problem, are then discussed. Currently, this source is capable of delivering comparable beam currents to the baseline source to the SNS and, an earlier version, has briefly demonstrated unanalyzed currents up to ∼100 mA (1 ms, 60 Hz) on the test stand. In particular, this paper discusses plasma ignition (dc and RF plasma guns), antenna reliability, magnet overheating, and insufficient beam persistence.

  9. Lead-Bismuth-Eutectic Spallation Neutron Source for Nuclear Transmuter

    International Nuclear Information System (INIS)

    Gohar, Y.; Herceg, J.; Krajtl, L.; Micklich, B.; Pointer, D.; Saiveau, J.; Sofu, T.; Finck, P.

    2002-01-01

    A lead-bismuth eutectic (LBE) spallation target design concept has been developed for the subcritical multiplier (SCM) design of the accelerator-driven test facility (ADTF). The design is based on a coaxial geometrical configuration, which has been carefully analyzed and designed to achieve an optimum performance. The target design description, the results from the parametric studies, and the design analyses including neutronics, heat transfer, and hydraulics analyses are given in this paper. A detailed MCNPX geometrical model for the target has been developed to generate heating rates and nuclear responses in the structural material for the design process. The beam has a uniform distribution of 600 MeV protons and 5-MW total power. A small LBE buffer is optimized to reduce the irradiation damage in the SCM fuel elements from the scatter protons and the high-energy neutrons, to maximize the neutron yield to the SCM operation, and to provide inlet and outlet manifolds for the LBE coolant. A special attention has been given to the target window design to enhance its lifetime. The window volumetric heating is 766 W/cm 3 relative to 750 W/cm 3 in LBE for a 40-μA/cm 2 current density. The results show that the nuclear heating from the proton beam diminishes at about 32 cm along the beam axis in the LBE target material. The neutron contribution to the atomic displacement is in the range of 94 to ∼100% for the structure material outside the proton beam path. In the beam window, the neutron contribution is ∼74% and the proton beam is responsible for more than 95% of the total gas production. The proton contribution to the gas production vanishes outside the beam path. The LBE average velocity is ∼2 m/s. The heat transfer and the hydraulics analyses have been iterated to reduce the maximum temperature and the thermal stress level in the target window to enhance its operating life. (authors)

  10. Big-bang nucleosynthesis with a long-lived charged massive particle including He4 spallation processes

    Science.gov (United States)

    Jittoh, Toshifumi; Kohri, Kazunori; Koike, Masafumi; Sato, Joe; Sugai, Kenichi; Yamanaka, Masato; Yazaki, Koichi

    2011-08-01

    We propose helium-4 spallation processes induced by long-lived stau in supersymmetric standard models, and investigate an impact of the processes on light elements abundances. We show that, as long as the phase space of helium-4 spallation processes is open, they are more important than stau-catalyzed fusion and hence constrain the stau property.

  11. Design and implementation of low-Q diffractometers at spallation sources

    International Nuclear Information System (INIS)

    Seeger, P.A.; Hjelm, R.P.

    1993-01-01

    Low-Q diffractometers at spallation sources that use time of flight methods have been successfully implemented at several facilities, including the Los Alamos Neutron Scattering Center. The proposal to build new, more powerful, advanced spallation sources using advanced moderator concepts will provide luminosity greater than 20 times the brightest spallation source available today. These developments provide opportunity and challenge to expand the capabilities of present instruments with new designs. The authors review the use of time of flight for low-Q measurements and introduce new designs to extend the capabilities of present-day instruments. They introduce Monte Carlo methods to optimize design and simulate the performance of these instruments. The expected performance of the new instruments are compared to present day pulsed source- and reactor-based small-angle neutron scattering instruments. They review some of the new developments that will be needed to use the power of brighter sources effectively

  12. Target development for the SINQ high-power neutron spallation source

    International Nuclear Information System (INIS)

    Wagner, Werner

    2002-01-01

    SINQ is a 1 MW class research spallation neutron source, driven by the PSI proton accelerator system. In terms of beam power, it is, by a large margin, the most powerful spallation neutron source currently in operation worldwide. As a consequence, target load levels prevail in SINQ which are beyond the realm of existing experience. Therefore, an extensive materials irradiation program (STIP) is currently underway which will help to select the proper structural material and make dependable life time estimates accounting for the real operating conditions that prevail in the facility. In parallel, both theoretical and experimental work is going on within the MEGAPIE (MEGAwatt Pilot Experiment) project, to develop a liquid lead-bismuth spallation target for a beam power level of 1MW

  13. Parameterization of neutron production double-differential cross section above several tens-MeV by the use of moving source model

    International Nuclear Information System (INIS)

    Kitsuki, Hirohiko; Shigyo, Nobuhiro; Ishibashi, Kenji

    2000-01-01

    The moving source model based on the Maxwell-like energy distribution with Gaussian shape terms are employed for analyzing the neutron emission spectra from proton-induced spallation reaction. The parallelization of the double differential cross section is made for the experimental and calculated neutron data in the energy region from several-tens MeV to 3 GeV. (author)

  14. Proton induced X-ray emission (PIXE) technique for determining multi-element composition of transformed hairy root cultures of Boerhaavia diffusa L. An important medicinal herb

    International Nuclear Information System (INIS)

    Lopamudra Sahu; Chand, P.K.; Ray, D.K.; Utkal University, Vani Vihar, Bhubaneswar, Odisha

    2014-01-01

    Therapeutically important inorganic elements in Agrobacterium rhizogenes-mediated genetically transformed hairy root cultures (HRCs) of a pharmaceutically significant herb Boerhaavia diffusa were quantified using proton induced X-ray emission technique. This was compared with that of roots from the naturally grown donor plant. Two macro-elements (Ca and K) and eight different trace elements namely V, Cr, Mn, Fe, Co, Cu Zn, and Ni were detected and their content was determined. In HRCs of a transformed rhizoclone, calcium and potassium had values which were significantly higher than that of in vivo roots. The concentrations of several trace elements, which are known to have a positive implication in human healthcare, were found to be either comparable (Fe) to that in the natural root samples or higher (Mn, Zn, Cr, Cu, Co) in the transformed rhizoclone. The genetically transformed HRCs can thus serve as a fast-proliferating renewable resource of medicinally useful minerals targeting specific diseases. (author)

  15. A comparative study of neutron activation analysis and proton-induced X-ray emission analysis for the determination of heavy metals in estuarine sediments

    Science.gov (United States)

    Randle, K.; Al-Jundi, J.; Mamas, C. J. V.; Sokhi, R. S.; Earwaker, L. G.

    1993-06-01

    Our work on heavy metals in the estuarine environment has involved the use of two multielement techniques: neutron activation analysis (NAA) and proton-induced X-ray emission (PIXE) analysis. As PIXE is essentially a surface analytical technique problems may arise due to sample inhomogeneity and surface roughness. In order to assess the contribution of these effects we have compared the results from PIXE analysis with those from a technique which analyzes a larger bulk sample rather than just the surface. An obvious method was NAA. A series of sediment samples containing particles of variable diameter were compared. Pellets containing a few mg of sediment were prepared from each sample and analyzed by the PIXE technique using both an absolute and a comparitive method. For INAA the rest of the sample was then irradiated with thermal neutrons and element concentrations determined from analyses of the subsequent gamma-ray spectrum. Results from the two methods are discussed.

  16. Proton Induced X-ray Emission Analysis of Sources of Raw for Blue-and-White Porcelain From Jingdezhen and Dehua Area

    International Nuclear Information System (INIS)

    Liu Shunmin; Yang Dawei; Li Rongwu; Li Guoxia; Cheng Huansheng; Zheng Jongxin; Chen Lifang

    2010-01-01

    In order to find out sources of raw, ingredients and classification relationship for Blue-and-White porcelain from Jingdezhen and Dehua area in different time, 34 Blue-and-White porcelain samples were selected. The chemical ingredients of every sample were determined by proton induced X-ray emission. The chemical ingredients data of all samples were further analyzed using fuzzy cluster analysis. The results indicate that the sources of raw and classification relationship of majority bodies from Blue-and-White porcelain of Dehua and Jingdezhen area are commendably differentiated. The sources of raw and batch formulas of eight transparent enamel samples from Jingdezhen area in Ming Dynasty and majority transparent enamel samples from Dehua area are commendably differentiated. Except one or two samples, majority Blue-and-White glaze samples from two areas are obviously different, and it might be an important path for non-destructive discrimination among Blue-and-White porcelains from two areas. (authors)

  17. Proton-induced accelerated decay of the fungicide, vinclozolin, on TiO2 surface under solar irradiation: Experimental and DFT study.

    Science.gov (United States)

    Osipov, Ivan; Gorbachev, Mikhail Y; Gorinchoy, Natalia N

    2018-04-03

    The photochemical degradation of vinclozolin by addition of titanium dioxide on silica support has been examined both experimental and quantum-chemically. Solar irradiation of vinclozolin on silica with and without addition of titanium dioxide for 6 h resulted in 21% and 97.8% vinclozolin residues, respectively. In both these cases, phototransformation leads to the formation of (3,5-dichlorophenyl isocyanate) and (3,5-dichloroaniline). The presence of the intermediary product resulted from opening of the 2,4-oxazolidine-dione ring is also confirmed by GS-MS and LC-MS chromatography. The proton-induced mechanism of vinclozolin decay at the above experimental conditions is clarified on the base of DFT calculations.

  18. Determination of Elemental Composition of Malabar spinach, Lettuce, Spinach, Hyacinth Bean, and Cauliflower Vegetables Using Proton Induced X-Ray Emission Technique at Savar Subdistrict in Bangladesh

    Directory of Open Access Journals (Sweden)

    S. M. Fahad

    2015-01-01

    Full Text Available The concentrations of 18 different elements (K, Ca, Fe, Cl, P, Zn, S, Mn, Ti, Cr, Rb, Co, Br, Sr, Ru, Si, Ni, and Cu were analyzed in five selected vegetables through Proton Induced X-ray Emission (PIXE technique. The objective of this study was to provide updated information on concentrations of elements in vegetables available in the local markets at Savar subdistrict in Bangladesh. These elements were found in varying concentrations in the studied vegetables. The results also indicated that P, Cl, K, Ca, Mn, Fe, and Zn were found in all vegetables. Overall, K and Ca exhibited the highest concentrations. Cu and Ni exhibited the lowest concentrations in vegetables. The necessity of these elements was also evaluated, based on the established limits of regulatory standards. The findings of this study suggest that the consumption of these vegetables is not completely free of health risks.

  19. Polarized proton induced pion production on 10B at 200, 225, 250 and 260 MeV incident energies

    International Nuclear Information System (INIS)

    Ziegler, W.; Auld, E.G.; Falk, W.R.; Giles, G.L.; Jones, G.; Lolos, G.J.; McParland, B.

    1985-02-01

    The angular distributions of both the differential cross-section and the analyzing power are presented for the 10 B(p,π) 11 B reaction leading to the ground and first excited states of 11 B. The differential cross-section shows very little angular structure or energy dependence, but the analyzing power exhibits a considerable energy dependence for both states. This dependence, similar to that observed for the 12 C(p,π + ) 13 C reaction, may be a signature of the fact that single-particle final states are involved

  20. Correlated analysis of 2 MeV proton-induced radiation damage in CdZnTe crystals using photoluminescence and thermally stimulated current techniques

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Yaxu [State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072 (China); Key Laboratory of Radiation Detection Materials and Devices of Ministry of Industry and Information Technology, Northwestern Polytechnical University, Xi’an 710072 (China); Jie, Wanqi, E-mail: jwq@nwpu.edu.cn [State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072 (China); Key Laboratory of Radiation Detection Materials and Devices of Ministry of Industry and Information Technology, Northwestern Polytechnical University, Xi’an 710072 (China); Rong, Caicai [Institute of Modern Physics, Applied Ion Beam Physics Laboratory, Fudan University, Shanghai 200433 (China); Wang, Yuhan; Xu, Lingyan; Xu, Yadong [State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072 (China); Key Laboratory of Radiation Detection Materials and Devices of Ministry of Industry and Information Technology, Northwestern Polytechnical University, Xi’an 710072 (China); Lv, Haoyan; Shen, Hao [Institute of Modern Physics, Applied Ion Beam Physics Laboratory, Fudan University, Shanghai 200433 (China); Du, Guanghua [Materials Research Center, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Fu, Xu [State Key Laboratory of Solidification Processing, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072 (China); Key Laboratory of Radiation Detection Materials and Devices of Ministry of Industry and Information Technology, Northwestern Polytechnical University, Xi’an 710072 (China); and others

    2016-11-01

    Highlights: • 2 MeV proton-induced radiation damage in CdZnTe crystals is investigated by PL and TSC techniques. • The influence of radiation damage on the luminescent and electrical properties of CdZnTe crystals is studied. • Intensity of PL spectrum is found to decrease significantly in irradiated regions, suggesting the increase of non-radiative recombination centers. • A correlated analysis of PL and TSC spectra suggests that the density of dislocations and A-centers increase after proton irradiation. - Abstract: Radiation damage induced by 2 MeV protons in CdZnTe crystals has been studied by means of photoluminescence (PL) and thermally stimulated current (TSC) techniques. A notable quenching of PL intensity is observed in the regions irradiated with a fluence of 6 × 10{sup 13} p/cm{sup 2}, suggesting the increase of non-radiative recombination centers. Moreover, the intensity of emission peak D{sub complex} centered at 1.48 eV dominates in the PL spectrum obtained from irradiated regions, ascribed to the increase of interstitial dislocation loops and A centers. The intensity of TSC spectra in irradiated regions decreases compared to the virgin regions, resulting from the charge collection inefficiency caused by proton-induced recombination centers. By comparing the intensity of identified traps obtained from numerical fitting using simultaneous multiple peak analysis (SIMPA) method, it suggests that proton irradiation under such dose can introduce high density of dislocation and A-centers in CdZnTe crystals, consistent with PL results.

  1. Geometric optimization of spallation targets for the MYRRHA reactor using MCNPX simulations

    Energy Technology Data Exchange (ETDEWEB)

    Rebello Junior, Andre Luiz P.; Martinez, Aquilino S.; Golcalves, Alessandro C., E-mail: junior.rebello@poli.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Dept. de Engenharia Nuclear

    2013-07-01

    The present work aims to evaluate the behavior of neutron multiplicity in a spallation target using MCNPX simulations, focusing on its application in the MYRRHA reactor. It was studied the two types of spallation target proposed for the MYRRHA project, windowless and windows target, in order to compare them and nd saturation boundaries. Some saturation boundaries were found and the windowless target proved to be as viable as the windows one. Each one produced nearly the same number of neutrons per incident proton. Using the concept of neutron cost, it was also observed that the optimum conditions on neutron production occur at about 1GeV, for both target designs. (author)

  2. Thin and thick target benchmark investigations to validate spallation physics models

    International Nuclear Information System (INIS)

    Filges, D.; Neef, R.D.; Goldenbaum, F.; Nuenighoff, K.; Galin, J.; Letourneau, A.; Lott, B.; Patois, Y.; Schroeder, W.N.

    1999-01-01

    In the ESS (European Spallation Source) study report several areas have been identified where further spallation physics research and code validation is urgently needed: Neutron and charged particle production and multiplicities above one GeV incident protons, energy deposition and heating, material damage parameters, radioactivity and after heat, and high energy source shielding. All simulation calculations will be done using the Juelich HERMES code system. For this purpose various collaborations were organised. One of the collaborations is NESSI (Neutron Scintillator Silicon Detector), which concerns fundamental data as cross-section measurements on neutron multiplicities and charged particles for different ESS relevant materials. (author)

  3. Geometric optimization of spallation targets for the MYRRHA reactor using MCNPX simulations

    International Nuclear Information System (INIS)

    Rebello Junior, Andre Luiz P.; Martinez, Aquilino S.; Golcalves, Alessandro C.

    2013-01-01

    The present work aims to evaluate the behavior of neutron multiplicity in a spallation target using MCNPX simulations, focusing on its application in the MYRRHA reactor. It was studied the two types of spallation target proposed for the MYRRHA project, windowless and windows target, in order to compare them and nd saturation boundaries. Some saturation boundaries were found and the windowless target proved to be as viable as the windows one. Each one produced nearly the same number of neutrons per incident proton. Using the concept of neutron cost, it was also observed that the optimum conditions on neutron production occur at about 1GeV, for both target designs. (author)

  4. Present status of spallation target development. JAERI/KEK Joint Project

    International Nuclear Information System (INIS)

    Hino, R.; Kaminaga, M.; Haga, K.

    2001-01-01

    The Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) are promoting a plan to construct a neutron scattering facility under the JAERI/KEK Joint Project. Design and R and D works are being carried out vigorously for realizing the mercury target system consisting of the mercury target, moderators and reflectors working as a spallation neutron source, as well as a remote handling system for exchanging such components which will be highly irradiated. This report introduces an outline of the present status of design and development activities on the spallation target system. (author)

  5. A comparison of microstructures in copper irradiated with fission, fusion, and spallation neutrons

    International Nuclear Information System (INIS)

    Muroga, T.; Heinisch, H.L.; Sommer, W.F.; Ferguson, P.D.

    1992-01-01

    The objective of this work is to investigate the effects of the neutron energy spectrum in low dose irradiations on the microstructure and mechanical properties of metals. The microstructures of pure copper irradiated to low doses at 36-90 C with spallation neutrons, fusion neutrons and fission neutrons are compared. The defect cluster densities for the spallation and fusion neutrons are very similar when compared on the basis of displacements per atom (dpa). In both cases, the density increases in proportion to the square root of the dpa. The difference in defect density between fusion neutrons and fission neutrons corresponds with differences observed in data on yield stress changes

  6. Calculations of radiation damage in target, container and window materials for spallation neutron sources

    International Nuclear Information System (INIS)

    Wechsler, M.S.; Mansur, L.K.

    1996-01-01

    Radiation damage in target, container, and window materials for spallation neutron sources is am important factor in the design of target stations for accelerator-driver transmutation technologies. Calculations are described that use the LAHET and SPECTER codes to obtain displacement and helium production rates in tungsten, 316 stainless steel, and Inconel 718, which are major target, container, and window materials, respectively. Results are compared for the three materials, based on neutron spectra for NSNS and ATW spallation neutron sources, where the neutron fluxes are normalized to give the same flux of neutrons of all energies

  7. Target station design for a 1 MW pulsed spallation neutron source

    International Nuclear Information System (INIS)

    Russell, G.J.; Baker, G.D.; Brewton, R.J.

    1993-01-01

    Target stations are vital components of the 1 MW, next generation spallation neutron source proposed for LANSCE. By and large, target stations design determines the overall performance of the facility. Many traditional concepts will probably have to be rethought, and many new concepts will have to be put forward to meet the 1 MW challenge. This article gives a brief overview of the proposed neutron spallation source from the target station viewpoint, as well as the general philosophy adopted for the design of the LANSCE-II target stations. Some of the saliant concepts and features envisioned for LANSCE-II are briefly described

  8. Superconducting Prototype Cavities for the Spallation Neutron Source (SNS) Project

    International Nuclear Information System (INIS)

    Ciovati, G.; Kneisel, P.; Brawley, J.; Bundy, R.; Campisi, I.; Davis, K.; Macha, K.; Machie, D.; Mammosser, J.; Morgan, S.; Sundelin, R.; Turlington, L.; Wilson, K.; Doleans, M.; Kim, S.H.; Barni, D.; Pagani, C.; Pierini, P.; Matsumoto, K.; Mitchell, R.; Schrage, D.; Parodi, R.; Sekutowicz, J.; Ylae-Oijala, P.

    2001-01-01

    The Spallation Neutron Source project includes a superconducting linac section in the energy range from 192 MeV to 1000 MeV, operating at a frequency of 805 MHz at 2.1 K. For this energy range two types of cavities are needed with geometrical beta - values of beta= 0.61 and beta= 0.81. An aggressive cavity prototyping program is being pursued at Jlab, which calls for fabricating and testing of four beta= 0.61 cavities and two beta= 0.81 cavities. Both types consist of six cells made from high purity niobium and feature one HOM coupler on each beam pipe and a port for a high power coaxial input coupler. Three of the four beta= 0.61 cavities will be used for a cryomodule test in early 2002. At this time four medium beta cavities and one high beta cavity have been completed at JLab. The first tests on the beta=0.61 cavity and the beta= 0.81 exceeded the design values for gradient and Q - value: E acc = 1 0.3 MV/m and Q = 5 x 10 9 at 2.1K for beta= 0.61 and E acc = 12.3 MV/m and Q = 5 x 10 9 at 2.1K for beta= 0.81. One of the medium beta cavities has been equipped with an integrated helium vessel and measurements of the static and dynamic Lorentz force detuning will be done and compared to the ''bare'' cavities. In addition two single cell cavities have been fabricated, equipped with welded-on HOM couplers. They are being used to evaluate the HOM couplers with respect to multipacting, fundamental mode rejection and HOM damping as far as possible in a single cell. This paper will describe the cavity design with respect to electrical and mechanical features, the fabrication efforts and the results obtained with the different cavities existing at the time of this workshop

  9. Preparation and Testing of Corrosion and Spallation-Resistant Coatings

    Energy Technology Data Exchange (ETDEWEB)

    Hurley, John

    2015-11-01

    with the Rene 80. One-inch-diameter buttons were machined from each of the bonded blocks and sent to Siemens for standard oxidation, spallation, and corrosion testing, which should be complete in the spring of 2016.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-03-01

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

  11. Final results of the 'Benchmark on computer simulation of radioactive nuclides production rate and heat generation rate in a spallation target'

    International Nuclear Information System (INIS)

    Janczyszyn, J.; Pohorecki, W.; Domanska, G.; Maiorino, R.J.; David, J.C.; Velarde, F.A.

    2011-01-01

    A benchmark has been organized to assess the computer simulation of nuclide production and heat generation in a spallation lead target. The physical models applied for the calculation of thick lead target activation do not produce satisfactory results for the majority of analysed nuclides, however one can observe better or worse quantitative compliance with the experimental results. Analysis of the quality of calculated results show the best performance for heavy nuclides (A: 170 - 190). For intermediate nuclides (A: 60 - 130) almost all are underestimated while for A: 130 - 170 mainly overestimated. The shape of the activity distribution in the target is well reproduced in calculations by all models but the numerical comparison shows similar performance as for the whole target. The Isabel model yields best results. As for the whole target heating rate, the results from all participants are consistent. Only small differences are observed between results from physical models. As for the heating distribution in the target it looks not quite similar. The quantitative comparison of the distributions yielded by different spallation reaction models shows for the major part of the target no serious differences - generally below 10%. However, in the most outside parts of the target front layers and the part of the target at its end behind the primary protons range, a spread higher than 40 % is obtained

  12. INFLUENCE OF MICROSTRUCTURAL ANISOTROPY ON THE SPALLATION OF 1080 EUTECTOID STEEL

    International Nuclear Information System (INIS)

    GRAY, G.T.; LOPEZ, M.F.

    2001-01-01

    While the influence of crystallographic texture on elastic and plastic constitutive response has seen extensive investigation in recent years, the influence of texture on the dynamic fracture of engineering materials remains less extensively explored. In particular, the influence of anisotropy, both textural and morphological, on the spallation behavior of materials remains poorly quantified. In this study, the spallation response of 1080-steel has been studied as a function of microstructural morphological anisotropy. In this study the influence of elongated MnS stringers, resident within a crystallographically isotropic eutectoid steel, on the spallation response of 1080 steel was investigated. That of a fully-pearlitic 1080 steel loaded to 5 GPa was found to be dominated by the heterogeneous nucleation of damage normal and orthogonal to the MnS stringers. Delamination between the matrix pearlitic microstructure and the MnS stringers was seen to correlate to a significantly lower pull-back signal during transverse loading than to that parallel to the stringer axis. The ''pull-back'' signals and post-spallation metallographic observations are discussed with reference to the influence of microstructural anisotropy on void nucleation and growth

  13. Analysis of phase velocity designing on superconducting section of proton Linac for spallation neutron source

    International Nuclear Information System (INIS)

    Ouyang Huafu; Xu Taoguang; Yu Qingchang; Guan Xialing; Luo Zihua

    2001-01-01

    A preliminary design of superconducting section of proton linac for spallation neutron source is made, which includes the design and optimization of the cavity shape and the architecture design of the superconducting section. In addition, the choice of the cell number of the superconducting cavity, the value of the geometric β G , the optimization principles of cavity and the beam dynamic properties are discussed

  14. SINQ - a continuous spallation neutron source (an approach to 1 MWatt of beam power)

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, W.E. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1995-11-01

    In this status report we describe the continuous spallation source at PSI, which will come into operation in fall 1996. We present the present state of the construction work and review the expected performance of the source. (author) 10 figs., 2 tabs., refs.

  15. Final environmental impact statement, construction and operation of the Spallation Neutron Source Facility. Summary

    International Nuclear Information System (INIS)

    1999-04-01

    DOE proposes to construct and operate a state-of-the-art, short-pulsed, spallation neutron source comprised of an ion source, a linear accelerator, a proton accumulator ring, and an experiment building containing a liquid mercury target and a suite of neutron scattering instrumentation. The proposed Spallation Neutron Source would be designed to operate at a proton beam power of 1 megawatt. The design would accommodate future upgrades to a peak operating power of 4 megawatts. These upgrades may include construction of a second proton accumulator ring and a second target. This document analyzes the potential environmental impacts from the proposed action and the alternatives. The analysis assumes a facility operating at a power of 1 MW and 4 MW over the life of the facility. The two primary alternatives analyzed in this FEIS are: the proposed action (to proceed with building the Spallation Neutron Source) and the No-Action Alternative. The No-Action Alternative describes the expected condition of the environment if no action were taken. Four siting alternatives for the Spallation Neutron Source are evaluated: Oak Ridge National Laboratory, Oak Ridge, TN, (preferred alternative); Argonne National Laboratory, Argonne, IL; Brookhaven National Laboratory, Upton, NY; and Los Alamos National Laboratory, Los Alamos, NM

  16. The biological shield of a high-intensity spallation source: a monte Carlo design study

    International Nuclear Information System (INIS)

    Koprivnikar, I.; Schachinger, E.

    2004-01-01

    The design of high-intensity spallation sources requires the best possible estimates for the biological shield. The applicability of three-dimensional Monte Carlo simulation in the design of the biological shield of a spallation source will be discussed. In order to achieve reasonable computing times along with acceptable accuracy, biasing techniques are to be employed and it was the main purpose of this work to develop a strategy for an effective Monte Carlo simulation in shielding design. The most prominent MC computer codes, namely MCNPX and FLUKA99, have been applied to the same model spallation source (the European Spallation Source) and on the basis of the derived strategies, the design and characteristics of the target station shield are discussed. It is also the purpose of the paper to demonstrate the application of the developed strategy for the design of beam lines with their shielding using as an example the target-moderator-reflector complex of the ESS as the primary particle source. (author)

  17. Investigation of the energy correlations of spallation neutrons by the MCNPX code

    International Nuclear Information System (INIS)

    Szieberth, Mate; Radocz, Gabor

    2011-01-01

    Earlier works have suggested that the energy correlations in a spallation source may influence the neutron noise measurements in an ADS. For the calculation of this effect not only the generally known and used one-particle spectrum is needed but also the so-called two particle spectrum, which describes also the energy correlations. Since measured data are not available for the energy distribution of the neutrons from a single spallation event the physical models of the MCNPX code have been used to investigate the effect. The calculational model has been successfully validated with measurements of the number distribution of spallation neutrons. The simulated one- and two-particle energy distributions and spectra proved that the energy correlations exist and have an important effect in low multiplicity spallation events and in thin targets. On the other hand for thick targets this effect appears negligible and the factorization of the two-particle spectrum seems an acceptable approximation. Further investigations are in hand to quantify the actual effect of the energy correlations on the neutron noise measurements. (author)

  18. SINQ - a continuous spallation neutron source (an approach to 1 MWatt of beam power)

    International Nuclear Information System (INIS)

    Fischer, W.E.

    1995-01-01

    In this status report we describe the continuous spallation source at PSI, which will come into operation in fall 1996. We present the present state of the construction work and review the expected performance of the source. (author) 10 figs., 2 tabs., refs

  19. Thermal hydraulic studies of lead–bismuth eutectic spallation target of CIADS

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Kang [Institute of Modern Physics, Chinese Academy of Sciences, 509 Nanchang Rd., Lanzhou, Gansu 730000 (China); University of Chinese Academy of Sciences, 19 A Yuquan Rd, Shijingshan District, Beijing 100049 (China); Yang, Yongwei, E-mail: yangyongwei@impcas.ac.cn [Institute of Modern Physics, Chinese Academy of Sciences, 509 Nanchang Rd., Lanzhou, Gansu 730000 (China); Fan, Deliang; Gao, Yucui [Institute of Modern Physics, Chinese Academy of Sciences, 509 Nanchang Rd., Lanzhou, Gansu 730000 (China)

    2016-08-15

    Highlights: • A 3-D fluid-solid coupling thermal-hydraulic analysis is made for the LBE target. • The reactor and the spallation target is coupled in thermal process. • The heat transfer between the inlet and outlet of the spallation target is taken into account. - Abstract: For the China Initiative Accelerator Driven System (CIADS), it includes three sub-systems: accelerator, spallation target, and sub-critical reactor. The sub-system of spallation target is an important component of the CIADS, which is coupled with the other two sub-systems. The proton beam from the accelerator with an energy of 250 MeV and a current intensity of 2 mA reacts with the nuclei of the lead–bismuth eutectic (LBE), approximately 0.5 MW of heat is deposited in the target zone, which must be removed by circulating the LBE. To reach the goal, we carried out the study by using the Computational Fluid Dynamics (CFD) software FLUENT, to study the flow patterns and temperature distribution in the target zone. For these simulations, the heat transferred from the sub-critical reactor was taken into account. The results indicated that the heat deposited in the target zone can be removed safely.

  20. Tensile property changes of metals and irradiated to low doses with fission, fusion and spallation neutrons

    International Nuclear Information System (INIS)

    Heinisch, H.L.; Hamilton, M.L.; Sommer, W.F.; Ferguson, P.D.

    1992-01-01

    The objective of this work is to investigate the effects of the neutron energy spectrum in low dose irradiations on the microstructures and mechanical properties of metals. Radiation effects due to low doses of spallation neutrons are compared directly to those produced by fission and fusion neutrons. Yield stress changes of pure Cu, alumina-dispersion-strengthened Cu and AISI 316 stainless steel irradiated at 36-55 C in the Los Alamos Spallation Radiation Effects Facility (LASREF) are compared with earlier results of irradiations at 90 C using 14 MeV D-T fusion neutrons at the Rotating Target Neutron Source and fission reactor neutrons in the Omega West Reactor. At doses up to 0.04 displacements per atom (dpa), the yield stress changes due to the three quite different neutron spectra correlate well on the basis of dpa in the stainless steel and the Cu alloy. However, in pure Cu, the measured yield stress changes due to spallation neutrons were anomalously small and should be verified by additional irradiations. With the exception of pure Cu, the low dose, low temperature experiments reveal no fundamental differences in radiation hardening by fission, fusion or spallation neutrons when compared on the basis of dpa

  1. Final environmental impact statement, construction and operation of the Spallation Neutron Source. Volume 1

    International Nuclear Information System (INIS)

    1999-04-01

    DOE proposes to construct and operate a state-of-the-art, short-pulsed, spallation neutron source comprised of an ion source, a linear accelerator, a proton accumulator ring, and an experiment building containing a liquid mercury target and a suite of neutron scattering instrumentation. The proposed Spallation neutron Source would be designed to operate at a proton beam power of 1 megawatt. The design would accommodate future upgrades to a peak operating power of 4 megawatts. These upgrades may include construction of a second proton accumulator ring and a second target. This document analyzes the potential environmental impacts from the proposed action and the alternatives. The analysis assumes a facility operating at a power of 1 MW and 4 MW over the life of the facility. The two primary alternatives analyzed in this FEIS are: the proposed action (to proceed with building the Spallation Neutron Source) and the No-Action Alternative. The No-Action Alternative describes the expected condition of the environment if no action were taken. Four siting alternatives for the Spallation Neutron Source are evaluated: Oak Ridge National Laboratory, Oak Ridge, TN, (preferred alternative); Argonne National Laboratory, Argonne, IL; Brookhaven National Laboratory, Upton, NY; and Los Alamos National Laboratory, Los Alamos, NM

  2. Laser-irradiated thermodynamic behaviors of spallation and recombination at solid-state interface

    International Nuclear Information System (INIS)

    Lai, H.-Y.; Huang, P.-H.

    2008-01-01

    A microscopic insight of interfacial spallation and recombination behaviors at multilayer thin-film interface induced by incident femtosecond pulsed laser is presented in this paper. Such two different aforementioned behaviors are investigated via the thermodynamic trajectories obtained by using standard Lennard-Jones (L-J) molecular dynamics (MD) simulation. Based on the simulation results, the interfacial damages of multilayer thin film are dominated by a critical threshold that induces an extraordinary expansive dynamics and phase transitions leading to the structural softened and tensile spallation at interface. The critical damage threshold is evaluated at around 8.5 J/m 2 which governs the possible occurrence of two different regimes, i.e. interfacial spallaiton and recombination. In interfacial damage region, quasi-isothermal thermodynamic trajectories can be observed after the interfacial spallation occurs. Moreover, the result of thermodynamic trajectories analyses indicates that, the relaxation of pressure wave may cause the over-heated interfacial zone to reduce volumetric density, thus leading to structural softness and even weaken interfacial structural strength. The crucial effect leading to the phenomenon of low tension spallation is identified

  3. A proposal for a long-pulse spallation source at Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Pynn, R; Weinacht, D [Los Alamos National Lab., NM (United States)

    1995-11-01

    Los Alamos National Laboratory is proposing a new spallation neutron source that will provide the U.S. with an internationally competitive facility for neutron science and technology that can be built in approximately three years for less than $100 million. The establishment of a 1-MW long-pulse spallation source (LPSS) at the Los Alamos Neutron Science Center (LANSCE) will meet many of the present needs of scientists in the neutron scattering community and provide a significant boost to neutron research in the U.S. The new facility will support the development of a future, more intense spallation neutron source, that is planned by DOE`s Office of Energy Research. Together with the existing short pulse spallation source (SPSS) at the Manual Lujan, Jr. Neutron Scattering Center (MLNSC) at Los Alamos, the new LPSS will provide U.S. scientists with a complementary pair of high-performance neutron sources to rival the world`s leading facilities in Europe. (author) 1 ref.

  4. Stress and adhesion of chromia-rich scales on ferritic stainless steels in relation with spallation

    Directory of Open Access Journals (Sweden)

    A. Galerie

    2004-03-01

    Full Text Available The relation between chromia scale spallation during oxidation or cooling down of ferritic stainless steels is generally discussed in terms of mechanical stresses induced by volume changes or differential thermal expansion. In the present paper, growth and thermal stress measurements in scales grown on different ferritic steel grades have shown that the main stress accumulation occurs during isothermal scale growth and that thermal stresses are of minor importance. However, when spallation occurs, it is always during cooling down. Steel-oxide interface undulation seems to play a major role at this stage, thus relating spallation to the metal mechanical properties, thickness and surface preparation. A major influence on spallation of the minor stabilizing elements of the steels was observed which could not be related to any difference in stress state. Therefore, an original inverted blister test was developed to derive quantitative values of the metal-oxide adhesion energy. These values clearly confirmed that this parameter was influenced by scale thickness and by minor additions, titanium greatly increasing adhesion whereas niobium decreased it.

  5. Modelling of an experiment for the study of neutron spallation source at JINR

    International Nuclear Information System (INIS)

    Kumawat, Harphool; Goyal, Uttam; Kumar, V.; Barashenkov, V.S.

    2002-01-01

    Intense neutron spallation source (INSS) is a necessary requirement of accelerator driven sub-critical systems. INSS are proposed to be generated using the high current proton beams. Some studies are conducted for the neutron flux, transmutation rates and energy gains and a larger number of related experiments are being planned

  6. BEAM-LOSS DRIVEN DESIGN OPTIMIZATION FOR THE SPALLATION NEUTRON SOURCE (SNS) RING.

    Energy Technology Data Exchange (ETDEWEB)

    WEI,J.; BEEBE-WANG,J.; BLASKIEWICZ,M.; CAMERON,P.; DANBY,G.; GARDNER,C.J.; JACKSON,J.; LEE,Y.Y.; LUDEWIG,H.; MALITSKY,N.; RAPARIA,D.; TSOUPAS,N.; WENG,W.T.; ZHANG,S.Y.

    1999-03-29

    This paper summarizes three-stage design optimization for the Spallation Neutron Source (SNS) ring: linear machine design (lattice, aperture, injection, magnet field errors and misalignment), beam core manipulation (painting, space charge, instabilities, RF requirements), and beam halo consideration (collimation, envelope variation, e-p issues etc.).

  7. Application of a controlled swirl in the XT-ADS spallation target

    International Nuclear Information System (INIS)

    Roelofs, F.; Siccama, N. B.; Jeanmart, H.; Tichelen, K. V.; Dierckx, M.; Schuurmans, P.

    2008-01-01

    Within the EUROTRANS project, a windowless spallation target is designed and assessed in which there is direct contact between the proton beamline vacuum from the accelerator and a lead-bismuth free surface flow. Windowless spallation targets, which are designed by SCK.CEN, based on their experience for the MYRRHA concept, are experimentally examined in a well instrumented water-loop at UCL. The design work and the experimental campaign are supported by numerical simulations which are performed at NRG. In the current paper, the application of a mild swirl in the windowless spallation target is assessed. For this purpose, SCK.CEN has designed and fabricate, a spallation target in which a controlled swirl is introduced in the annular feeder of the target nozzle. An experimental programme is performed at UCL in their water-loop to evaluate various swirl strengths in one specific target nozzle design. Prior to the experimental programme, numerical simulations were performed at NRG assessing the influence of various swirl strengths on the free surface behaviour. Experimental and numerical results show that a mild swirl stabilizes the free surface and also indicate that applying a stronger swirl leads to undesired free surface behaviour, ultimately leading to a strong vortex in the central downcomer. (authors)

  8. Beam-Loss Driven Design Optimization for the Spallation Neutron Source (SNS) Ring

    International Nuclear Information System (INIS)

    Wei, J.

    1999-01-01

    This paper summarizes three-state design optimization for the Spallation Neutron Source (SNS) ring: linear machine design (lattice, aperture, injection, magnet field errors and misalignment), beam core manipulation (painting, space charge, instabilities, RF requirements), and beam halo consideration (collimation, envelope variation, e-p issues etc.)

  9. Measurements of gas and volatile element production rates from an irradiated molten lead and lead-bismuth spallation target with proton beams of 1 and 1.4 GeV

    International Nuclear Information System (INIS)

    Tall, Y.

    2008-03-01

    The integrated project EUROTRANS (European Research Programme for the Transmutation of High Level Nuclear Waste in an Accelerator Driven System) of the 6. EURATOM Framework Programme aims to demonstrate the transmutation of radioactive waste in ADS (Accelerator Driven Sub-critical system). It will carry out a first advanced design of an experimental facility to demonstrate the technical feasibility of transmutation, and will produce a conceptual design of an industrial facility dedicated to transmutation. An ADS consists of three fundamental elements: the accelerator of protons, the sub-critical core and the spallation target. SUBATECH (physique Sub-Atomique et des Technologies associees) laboratory is involved to the study of the chosen liquid lead-bismuth as a spallation ADS target. The irradiation of liquid lead-bismuth target with energetic proton beam generates in addition to neutrons, volatile and radioactive residues. In order to determine experimentally the production rates of gas and volatile elements following a spallation reaction in a lead-bismuth target, the experiment IS419 was performed at the ISOLDE facility at CERN (Centre Europeen de la Recherche Nucleaire). This experiment constitutes the frame of the thesis whose main objective is to assess and study the production and release rates of many gas and volatile element from the irradiated lead-bismuth target with an energetic proton beam. The obtained data are compared to Monte Carlo simulation code (MCNPX) results in order to test the intranuclear cascade model of Bertini and of Cugnon, and the evaporation options of Dresner and Schmidt. (author)

  10. Study of particle transport in a high power spallation target for an accelerator-driven transmutation system

    International Nuclear Information System (INIS)

    Shetty, Nikhil Vittal

    2013-01-01

    AGATE is a project envisaged to demonstrate the feasibility of transmutation in a gas (helium) cooled accelerator-driven system using solid spallation target. Development of the spallation target module and assessing its safety aspects are studied in this work. According to the AGATE concept parameters, 600 MeV protons are delivered on to the segmented tungsten spallation target. The Monte Carlo toolkit Geant4 has been used in the simulation of particle transport. Binary cascade is used to simulate intra-nuclear cascades, along with the G4NDL neutron data library for low energy neutrons (<20 MeV).

  11. Study of particle transport in a high power spallation target for an accelerator-driven transmutation system

    Energy Technology Data Exchange (ETDEWEB)

    Shetty, Nikhil Vittal

    2013-01-31

    AGATE is a project envisaged to demonstrate the feasibility of transmutation in a gas (helium) cooled accelerator-driven system using solid spallation target. Development of the spallation target module and assessing its safety aspects are studied in this work. According to the AGATE concept parameters, 600 MeV protons are delivered on to the segmented tungsten spallation target. The Monte Carlo toolkit Geant4 has been used in the simulation of particle transport. Binary cascade is used to simulate intra-nuclear cascades, along with the G4NDL neutron data library for low energy neutrons (<20 MeV).

  12. Investigating the intra-nuclear cascade process using the reaction 136Xe on deuterium at 500 AMeV

    Directory of Open Access Journals (Sweden)

    Rejmund F.

    2010-10-01

    Full Text Available More than 600 residual nuclei, formed in the spallation of 136Xe projectiles impinging on deuterium at 500 AMeV of incident energy, have been unambiguously identified and their production cross sections have been determined with high accuracy. By comparing these data to others previously measured for the reactions 136Xe  +  p at 1 AGeV and 136Xe  +  p at 500 AMeV we investigated the role that neutrons play in peripheral collisions and to understand the energy dissipation in frontal collisions in spallation reactions.

  13. Penetration by artificial electron acceptors of the plasma membrane-bound redox system into intact Zea mays L. roots investigated by proton-induced X-ray emission

    International Nuclear Information System (INIS)

    Luthje, S.; Doring, O.; Grossmann, D.; Niecke, M.; Bottger, M.

    1993-01-01

    Proton-induced X-ray emission was used to investigate the penetration of compounds of the membrane-impermeant electron acceptors hexabromoiridate IV, hexachloroiridate IV, and hexacyanoferrate III into corn (Zea mays L.) roots. Maps of the heavy element distribution in cross-sections of fixed, epoxy-embedded roots showed for hexabromoiridate IV small amounts of Br in samples treated for 24 h with concentrations normally used in physiological experiments (0.02 mM). After treatment with high concentrations (0.8 mM) of these complexes, Fe and Ir as well as Br were found in root cross-sections. In samples taken at a distance of 5 mm behind the root tip, we found an even distribution of Fe, Ir, and Br over the whole cross-section. In samples taken 15 mm behind the root tip, about 99% of both Br and Ir was confined to the rhizodermal cell layer. The distribution did not change with the complex used. These data are consistent with the view that apoplastic diffusion of the electron acceptors was blocked by the hypodermal Casparian band

  14. Measurements of isomeric yield ratios of fission products from proton-induced fission on natU and 232Th via direct ion counting

    Directory of Open Access Journals (Sweden)

    Rakopoulos Vasileios

    2017-01-01

    Full Text Available Independent isomeric yield ratios (IYR of 81Ge, 96Y, 97Y, 97Nb, 128Sn and 130Sn have been determined in the 25 MeV proton-induced fission of natU and 232Th. The measurements were performed at the Ion Guide Isotope Separator On-Line (IGISOL facility at the University of Jyväskylä. A direct ion counting measurement of the isomeric fission yield ratios was accomplished for the first time, registering the fission products in less than a second after their production. In addition, the IYRs of natU were measured by means of γ-spectroscopy in order to verify the consistency of the recently upgraded experimental setup. From the obtained results, indications of a dependence of the production rate on the fissioning system can be noticed. These data were compared with data available in the literature, whenever possible. Using the TALYS code and the experimentally obtained IYRs, we also deduced the average angular momentum of the fission fragments after scission.

  15. Multi-element analysis of the rat hippocampus by proton induced x-ray emission spectroscopy (phosphorus, sulfur, chlorine, potassium, calcium, iron, zinc, copper, lead, bromine, and rubidium)

    Energy Technology Data Exchange (ETDEWEB)

    Kemp, K.; Danscher, G.

    1979-01-22

    A technique for multi-element analysis of brain tissue by proton induced x-ray emission spectroscopy (PIXE) is described and data from analysis of fixed and unfixed samples from rat hippocampus, neocortex, amygdala, and spinal cord are presented and commented on. The atoms present in the tissue are bombarded with protons which cause the ejection of electrons from the inner shells. When the holes are refilled with electrons from outer shells, x-ray quanta characteristic for each element are emitted. Using a high resolution energy dispersive detector, a complete x-ray spectrum of the specimen can be recorded in a single measurement. Detection limits less than or approximately 5 ppM of dry matter are obtained for most elements with atomic number greater than 14 (silicon). Around 13 elements were found in concentrations above the detection limits. The grand means for non-fixed hippocampi were e.g., for Zn-120 ppM; Rb-20 ppM; Fe-150 ppM; Pb-3 ppM; Ni-5 ppM.

  16. Mass-yield distributions of fission products from 20, 32, and 45 MeV proton-induced fission of 232Th

    Science.gov (United States)

    Naik, H.; Goswami, A.; Kim, G. N.; Kim, K.; Suryanarayana, S. V.

    2013-10-01

    The yields of various fission products in the 19.6, 32.2, and 44.8 MeV proton-induced fission of 232Th have been determined by recoil catcher and an off-line γ-ray spectrometric technique using the BARC-TIFR Pelletron in India and MC-50 cyclotron in Korea. The mass-yield distributions were obtained from the fission product yield using the charge distribution corrections. The peak-to-valley (P/V) ratio of the present work and that of literature data for 232Th(p,f) and 238U(p,f) were obtained from the mass yield distribution. The present and the existing literature data for 232Th(p,f), 232Th(n,f), and 232Th( γ,f) at various energies were compared with those for 238U(p,f), 238U(n,f), and 238U( γ,f) to examine the probable nuclear structure effect. The role of Th-anomaly on the peak-to-valley ratio in proton-, neutron-, and photon-induced fission of 232Th was discussed with the similar data in 238U. On the other hand, the fine structure in the mass yield distributions of the fissioning systems at various excitation energies has been explained from the point of standard I and II asymmetric mode of fission besides the probable role of even-odd effect, A/ Z ratio, and fissility parameter.

  17. Proton induced single event upset cross section prediction for 0.15 μm six-transistor (6T) silicon-on-insulator static random access memories

    International Nuclear Information System (INIS)

    Li Lei; Zhou Wanting; Liu Huihua

    2012-01-01

    In this paper, an efficient physics-based method to estimate the saturated proton upset cross section for six-transistor (6T) silicon-on-insulator (SOI) static random access memory (SRAM) cells using layout and technology parameters is proposed. This method calculates the effects of radiation based on device physics. The simple method handles the problem with ease by SPICE simulations, which can be divided into two stages. At first, it uses a standard SPICE program to predict the cross section for recoiling heavy ions with linear energy transfer (LET) of 14 MeV-cm 2 /mg. Then, the predicted cross section for recoiling heavy ions with LET of 14 MeV-cm 2 /mg is used to estimate the saturated proton upset cross section for 6T SOI SRAM cells with a simple model. The calculated proton induced upset cross section based on this method is in good agreement with the test results of 6T SOI SRAM cells processed using 0.15 μm technology. (author)

  18. Proton induced L{sub 1}, L{sub 2}, L{sub 3}-sub-shell X-ray production cross sections of Hf and Au

    Energy Technology Data Exchange (ETDEWEB)

    Bertol, A.P.L., E-mail: anapaula.bertol@gmail.com [Programa de Pós-graduação em Física, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Hinrichs, R. [Programa de Pós-graduação em Física, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Instituto de Geociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Vasconcellos, M.A.Z. [Programa de Pós-graduação em Física, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil); Instituto de Física, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS (Brazil)

    2015-11-15

    Experimental data for proton induced X-ray production cross sections of L-sub-shells of Hf and Au were obtained, in order to contribute to the existing data sets and to support refinements of the ECPSSR theory. X-ray emissions of mono-elemental 10 nm films of Hf and Au were excited with 0.7–1.5 MeV protons. The measured L-line spectra were fitted assuming Gaussian shapes and constraining peak positions and line widths. The transition energy values used to establish peak positions were based on values proposed in the literature, while the line widths were matched to the detector resolution, obtained independently. The intensity of each line was obtained from the adjusted areas, without the use of emission rates. The line intensities were summed in α, β, γ, and ℓ groups to validate the measurements by comparison with existing data, and in L{sub 1}, L{sub 2}, L{sub 3}-sub-shells for comparison with ECPSSR-UA theory. Ratios of the emission rates of lines of the same sub-shell were obtained and compared with the data from the literature.

  19. Development of proton-induced x-ray emission techniques with application to multielement analyses of human autopsy tissues and obsidian artifacts

    International Nuclear Information System (INIS)

    Nielson, K.K.

    1975-01-01

    A method of trace element analysis using proton-induced x-ray emission (PIXE) techniques with energy dispersive x-ray detection methods is described. Data were processed using the computer program ANALEX. PIXE analysis methods were applied to the analysis of liver, spleen, aorta, kidney medulla, kidney cortex, abdominal fat, pancreas, and hair from autopsies of Pima Indians. Tissues were freeze dried and low temperature ashed before analysis. Concentrations were tabulated for K, Ca, Ti, Mn, Fe, Co, Ni, Cu, Zn, Pb, Se, Br, Rb, Sr, Cd, and Cs and examined for significant differences related to diabetes. Concentrations of Ca and Sr in aorta, Fe and Rb in spleen and Mn in liver had different patterns in diabetics than in nondiabetics. High Cs concentrations were also observed in the kidneys of two subjects who died of renal disorders. Analyses by atomic absorption and PIXE methods were compared. PIXE methods were also applied to elemental analysis of obsidian artifacts from Campeche, Mexico. Based on K, Ba, Mn, Fe, Rb, Sr and Zr concentrations, the artifacts were related to several Guatemalan sources. (Diss. Abstr. Int., B)

  20. CFD Study of the Active Part of the HYPER LBE Spallation Target System

    International Nuclear Information System (INIS)

    Cho, Chung-ho; Tak, Nam-il; Lee, Yong-bum; Choi, Jae-Hyuk

    2007-01-01

    In an accelerator driven system (ADS), a high-energy proton beam impinges on a heavy metal target to produce spallation neutrons that are multiplied in a subcritical blanket. Therefore, the spallation target is one of the most important units of an ADS. A beam power of 15-25 MW is required for an operation of the HYPER system. But, the design of a 20 MW spallation target is very challenging because more than 60% of a beam power is deposited as heat in a small volume of a target system. LBE is preferred as the target material due to its high neutron production rate, effective heat removal, low melting point and vapor pressure, low neutron absorption and good radiation damage properties. In addition, it can be used simultaneously as a reactor coolant. Single hemi-spherical beam window is considered for the HYPER target. The beam window is a thin physical barrier to separate the vacuum space from the LBE. It is exposed to high thermal and irradiation loads, which affect its life time. The integrity of the beam window is crucial for a safe operation of the HYPER, for preventing the penetration of the radioactive spallation products into the accelerator island. Therefore, a sufficient cooling capability of the beam window is one of the key issues of the target design. In the previous study, a series of parametric thermal and mechanical studies were made for the optimization of the HYPER target. The optimized target has a 0.2 cm thick beam window with a diameter of 35 cm. Also, a 30 cm wide proton beam with a uniform beam distribution should be adopted for the spallation target of the HYPER. A dual injection tube is adopted to economize the LBE flow in the primary system. This paper presents the numerical studies on the optimized spallation target system. Several advanced turbulence models with different grid structures are investigated by using a commercial computational fluid dynamics (CFD) code CFX 5.7.1