Sample records for mev cross sections

  1. Neutron-induced fission cross section of 242Pu from 15 MeV to 20 MeV

    NASA Astrophysics Data System (ADS)

    Jovančević, N.; Salvador-Castineira, P.; Daraban, L.; Vidali, M.; Heyse, J.; Oberstedt, S.; Hambsch, F.-J.; Bonaldi, C.; Geerts, W.

    2017-09-01

    Accurate nuclear-data needs in the fast-neutron-energy region have been recently addressed for the development of next generation nuclear power plants (GEN-IV) by the OECD Nuclear Energy Agency (NEA). This sensitivity study has shown that of particular interest is the 242Pu(n,f) cross section for fast reactor systems. Measurements have been performed with quasi-monoenergetic neutrons in the energy range from 15 MeV to 20 MeV produced by the Van de Graaff accelerator of the JRC-Geel. A twin Frisch-grid ionization chamber has been used in a back-to-back configuration as fission fragment detector. The 242Pu(n,f) cross section has been normalized to 238U(n,f) cross section data. The results were compared with existing literature data and show acceptable agreement within 5%.

  2. Measurements of neutron capture cross sections on 70Zn at 0.96 and 1.69 MeV

    NASA Astrophysics Data System (ADS)

    Punte, L. R. M.; Lalremruata, B.; Otuka, N.; Suryanarayana, S. V.; Iwamoto, Y.; Pachuau, Rebecca; Satheesh, B.; Thanga, H. H.; Danu, L. S.; Desai, V. V.; Hlondo, L. R.; Kailas, S.; Ganesan, S.; Nayak, B. K.; Saxena, A.

    2017-02-01

    The cross sections of the 70Zn(n ,γ )Zn71m (T1 /2=3.96 ±0.05 -h ) reaction have been measured relative to the 197Au(n ,γ )198Au cross sections at 0.96 and 1.69 MeV using a 7Li(p ,n )7Be neutron source and activation technique. The cross section of this reaction has been measured for the first time in the MeV region. The new experimental cross sections have been compared with the theoretical prediction by talys-1.6 with various level-density models and γ -ray strength functions as well as the tendl-2015 library. The talys-1.6 calculation with the generalized superfluid level-density model and Kopecky-Uhl generalized Lorentzian γ -ray strength function predicted the new experimental cross sections at both incident energies. The 70Zn(n ,γ ) g+m 71Zn total capture cross sections have also been derived by applying the evaluated isomeric ratios in the tendl-2015 library to the measured partial capture cross sections. The spectrum averaged total capture cross sections derived in the present paper agree well with the jendl-4.0 library at 0.96 MeV, whereas it lies between the tendl-2015 and the jendl-4.0 libraries at 1.69 MeV.

  3. Neutron-induced fission cross section of 240Pu from 0.5 MeV to 3 MeV

    NASA Astrophysics Data System (ADS)

    Salvador-Castiñeira, P.; Bryś, T.; Eykens, R.; Hambsch, F.-J.; Göök, A.; Moens, A.; Oberstedt, S.; Sibbens, G.; Vanleeuw, D.; Vidali, M.; Pretel, C.

    2015-07-01

    240Pu has recently been pointed out by a sensitivity study of the Organization for Economic Cooperation and Development (OECD) Nuclear Energy Agency (NEA) to be one of the isotopes whose fission cross section lacks accuracy to meet the upcoming needs for the future generation of nuclear power plants (GEN-IV). In the High Priority Request List (HPRL) of the OECD, it is suggested that the knowledge of the 240Pu(n ,f ) cross section should be improved to an accuracy within 1-3 %, compared to the present 5%. A measurement of the 240Pu cross section has been performed at the Van de Graaff accelerator of the Joint Research Center (JRC) Institute for Reference Materials and Measurements (IRMM) using quasi-monoenergetic neutrons in the energy range from 0.5 MeV to 3 MeV. A twin Frisch-grid ionization chamber (TFGIC) has been used in a back-to-back configuration as fission fragment detector. The 240Pu(n ,f ) cross section has been normalized to three different isotopes: 237Np(n ,f ) , 235U (n ,f ) , and 238U (n ,f ) . Additionally, the secondary standard reactions were benchmarked through measurements against the primary standard reaction 235U (n ,f ) in the same geometry. A comprehensive study of the corrections applied to the data and the associated uncertainties is given. The results obtained are in agreement with previous experimental data at the threshold region. For neutron energies higher than 1 MeV, the results of this experiment are slightly lower than the ENDF/B-VII.1 evaluation, but in agreement with the experiments of Laptev et al. (2004) as well as Staples and Morley (1998).

  4. Neutron total cross section measurement at WNR. [215 to 250 MeV experimental techniques

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lisowski, P.W.; Moore, M.S.; Morgan, G.L.

    1979-01-01

    The techniques involved in measuring fast-neutron total cross sections at the Weapons Neutron Facility (WNR) of the Los Alamos Scientific Laboratory are described. Results of total cross section measurements on natural carbon covering the range 2.5 to 250 MeV are presented. 16 references.

  5. 54Fe neutron elastic and inelastic scattering differential cross sections from 2-6 MeV

    NASA Astrophysics Data System (ADS)

    Vanhoy, J. R.; Liu, S. H.; Hicks, S. F.; Combs, B. M.; Crider, B. P.; French, A. J.; Garza, E. A.; Harrison, T.; Henderson, S. L.; Howard, T. J.; McEllistrem, M. T.; Nigam, S.; Pecha, R. L.; Peters, E. E.; Prados-Estévez, F. M.; Ramirez, A. P. D.; Rice, B. G.; Ross, T. J.; Santonil, Z. C.; Sidwell, L. C.; Steves, J. L.; Thompson, B. K.; Yates, S. W.

    2018-04-01

    Measurements of neutron elastic and inelastic scattering cross sections from 54Fe were performed for nine incident neutron energies between 2 and 6 MeV. Measured differential scattering cross sections are compared to those from previous measurements and the ENDF, JENDL, and JEFF data evaluations. TALYS calculations were performed and modifications of the default parameters are found to better describe the experimental cross sections. A spherical optical model treatment is generally adequate to describe the cross sections in this energy region; however, in 54Fe the direct coupling is found to increase suddenly above 4 MeV and requires an increase in the DWBA deformation parameter by approximately 25%. This has little effect on the elastic scattering differential cross sections but makes a significant improvement in both the strength and shape of the inelastic scattering angular distribution, which are found to be very sensitive to the size and extent of the surface absorption region.

  6. Total cross section for the γd-->π-pp reaction between 380 and 840 MeV

    NASA Astrophysics Data System (ADS)

    Asai, M.; Endo, I.; Harada, M.; Kasai, S.; Niki, K.; Sumi, Y.; Kato, S.; Maruyama, K.; Murata, Y.; Muto, M.; Yoshida, K.; Iwatani, K.; Hasai, H.; Ito, H.; Maki, T.; Rangacharyulu, C.; Shimizu, H.; Wada, Y.

    1990-09-01

    The total cross section for the γd-->π-pp reaction has been measured for incident photon energies from 380 to 840 MeV in steps of 10 MeV, with the best energy resolution attained so far. A large-acceptance detector was used to observe the reaction products. Overall uncertainties in the deduced cross sections are less than 9% (~4% statistical and ~8% systematic). The results are in excellent agreement with previous bubble chamber measurements and do not show any statistically significant structure which can be interpreted as evidence for the formation of dibaryon resonances. An upper limit at 95% confidence level of σpeakΓ<230 μb MeV is obtained for a resonance in the vicinity of photon energy 700 MeV (mass~2490 MeV).

  7. Measurement of Neutron Reaction Cross Sections between 8 and 14 MeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mannhart, Wolf; Schmidt, Dankwart

    2005-05-24

    Cross-section measurements were performed with special emphasis on access to the 'blind spot' in the neutron energy range from 10 to 13 MeV. The use of a conventional D(d,n) neutron source in combination with TOF measurements of the D(d,np) break-up component allows the precise determination of monoenergetic cross-section data in this range. The procedure is demonstrated with the measurement of the cross sections of 64Zn(n,p)64Cu, 64Zn(n,2n)63Zn, 63Cu(n,2n)62Cu, and 65Cu(n,2n)64Cu. With all reaction products being strong positron emitters, the radioactivity-counting process has been optimised for a perfect registration of the associated annihilation radiation.

  8. Measurement of Neutron Reaction Cross Sections between 8 and 14 MeV

    NASA Astrophysics Data System (ADS)

    Mannhart, Wolf; Schmidt, Dankwart

    2005-05-01

    Cross-section measurements were performed with special emphasis on access to the "blind spot" in the neutron energy range from 10 to 13 MeV. The use of a conventional D(d,n) neutron source in combination with TOF measurements of the D(d,np) break-up component allows the precise determination of monoenergetic cross-section data in this range. The procedure is demonstrated with the measurement of the cross sections of 64Zn(n,p)64Cu, 64Zn(n,2n)63Zn, 63Cu(n,2n)62Cu, and 65Cu(n,2n)64Cu. With all reaction products being strong positron emitters, the radioactivity-counting process has been optimised for a perfect registration of the associated annihilation radiation.

  9. The 13C(n,α0)10Be cross section at 14.3 MeV and 17 MeV neutron energy

    NASA Astrophysics Data System (ADS)

    Kavrigin, P.; Belloni, F.; Frais-Koelbl, H.; Griesmayer, E.; Plompen, A. J. M.; Schillebeeckx, P.; Weiss, C.

    2017-09-01

    At nuclear fusion reactors, CVD diamond detectors are considered an advantageous solution for neutron flux monitoring. For such applications the knowledge of the cross section of neutron-induced nuclear reactions on natural carbon are of high importance. Especially the (n,α0) reactions, yielding the highest energy reaction products, are of relevance as they can be clearly distinguished in the spectrum. The 13C(n,α0)10Be cross section was measured relative to 12C(n,α0)9Be at the Van de Graaff facility of EC-JRC Geel, Belgium, at 14.3 MeV and 17.0 MeV neutron energies. The measurement was performed with an sCVD (single-crystal Chemical Vapor Deposition) diamond detector, where the detector material acted simultaneously as sample and as sensor. A novel data analysis technique, based on pulse-shape discrimination, allowed an efficient reduction of background events. The results of the measurement are presented and compared to previously published values for this cross-section.

  10. Total and differential cross sections of η-production in proton-deuteron fusion for excess energies between Qη = 13 MeV and Qη = 81 MeV

    NASA Astrophysics Data System (ADS)

    Adlarson, P.; Augustyniak, W.; Bardan, W.; Bashkanov, M.; Bergmann, F. S.; Berłowski, M.; Bondar, A.; Büscher, M.; Calén, H.; Ciepał, I.; Clement, H.; Czerwiński, E.; Demmich, K.; Engels, R.; Erven, A.; Erven, W.; Eyrich, W.; Fedorets, P.; Föhl, K.; Fransson, K.; Goldenbaum, F.; Goswami, A.; Grigoryev, K.; Gullström, C.-O.; Heijkenskjöld, L.; Hejny, V.; Hüsken, N.; Jarczyk, L.; Johansson, T.; Kamys, B.; Kemmerling, G.; Khatri, G.; Khoukaz, A.; Khreptak, A.; Kirillov, D. A.; Kistryn, S.; Kleines, H.; Kłos, B.; Krzemień, W.; Kulessa, P.; Kupść, A.; Kuzmin, A.; Lalwani, K.; Lersch, D.; Lorentz, B.; Magiera, A.; Maier, R.; Marciniewski, P.; Mariański, B.; Morsch, H.-P.; Moskal, P.; Ohm, H.; Parol, W.; Perez del Rio, E.; Piskunov, N. M.; Prasuhn, D.; Pszczel, D.; Pysz, K.; Pyszniak, A.; Ritman, J.; Roy, A.; Rudy, Z.; Rundel, O.; Sawant, S.; Schadmand, S.; Schätti-Ozerianska, I.; Sefzick, T.; Serdyuk, V.; Shwartz, B.; Sitterberg, K.; Skorodko, T.; Skurzok, M.; Smyrski, J.; Sopov, V.; Stassen, R.; Stepaniak, J.; Stephan, E.; Sterzenbach, G.; Stockhorst, H.; Ströher, H.; Szczurek, A.; Trzciński, A.; Wolke, M.; Wrońska, A.; Wüstner, P.; Yamamoto, A.; Zabierowski, J.; Zieliński, M. J.; Złomańczuk, J.; Żuprański, P.; Żurek, M.; Wilkin, C.; WASA-at-COSY Collaboration

    2018-07-01

    New data on both total and differential cross sections of the production of η mesons in proton-deuteron fusion to 3He η in the excess energy region 13.6MeV ≤Qη ≤ 80.9MeV are presented. These data have been obtained with the WASA-at-COSY detector setup located at the Forschungszentrum Jülich, using a proton beam at 15 different beam momenta between pp = 1.60GeV / c and pp = 1.74GeV / c. While significant structure of the total cross section is observed in the energy region 20MeV ≲Qη ≲ 60MeV, a previously reported sharp variation around Qη ≈ 50MeV cannot be confirmed. Angular distributions show the typical forward-peaking that was noted earlier. For the first time, it is possible to study the development of these angular distributions with rising excess energy over a wide interval.

  11. Cross-section measurement for the 67Zn(n, α)64Ni reaction at 6.0 MeV

    NASA Astrophysics Data System (ADS)

    Zhang, Guohui; Wu, Hao; Zhang, Jiaguo; Liu, Jiaming; Chen, Jinxiang; Gledenov, Yu. M.; Sedysheva, M. V.; Khuukhenkhuu, G.; Szalanski, P. J.

    2010-01-01

    Up to now, no experimental cross-section data exist for the 67Zn ( n, α) 64Ni reaction in the MeV neutron energy region. In the present work, the cross-section of the 67Zn ( n, α) 64Ni reaction was measured at E n = 6.0 MeV. Experiments were performed at the Van de Graaff accelerator of Peking University, China. Fast neutrons were produced through the D ( d, n) 3He reaction using a deuterium gas target. Absolute neutron flux was determined by a small 238U fission chamber and a BF3 long counter was used as a neutron flux monitor. A twin gridded ionization chamber was employed as the α -particle detector and two back-to-back 67Zn samples were used for α events measurement. Background was measured and subtracted from foreground. The measured cross-section of the 67Zn ( n, α) 64Ni reaction was 7.3 (1±15%) mb at 6.0MeV. The present result was compared with existing evaluations and TALYS code calculations.

  12. Attempt to Measure (n, xn) Double-Differential Cross Sections for Incident Neutron Energies above 100 MeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Watanabe, T.; Kunieda, S.; Shigyo, N.

    The experimental technique for measurement of (n, xn) double differential cross sections for incident neutron energy above 100 MeV has been attempted to be developed with continuous-energy neutrons up to 400 MeV. Neutrons were produced in the spallation reaction by the 800 MeV proton beam, which was incident on a thick, heavily shielded tungsten target at the WNR facility at Los Alamos National Laboratory. The energies of incident neutrons were determined by the time-of-flight method. Emitted neutrons were detected by the recoil proton method. A phoswich detector consisting of NaI(Tl) and NE102A plastic scintillators was used for detecting recoil protons.more » We compared the preliminary experimental cross section data with the calculations by PHITS and QMD codes.« less

  13. New Evaluated Semi-Empirical Formula Using Optical Model for 14-15 MeV ( n, t) Reaction Cross Sections

    NASA Astrophysics Data System (ADS)

    Tel, E.; Durgu, C.; Aydın, A.; Bölükdemir, M. H.; Kaplan, A.; Okuducu, Ş.

    2009-12-01

    In the next century the world will face the need for new energy sources. Nuclear fusion can be one of the most attractive sources of energy from the viewpoint of safety and minimal environmental impact. Fusion will not produce CO2 or SO2 and thus will not contribute to global warming or acid rain. Achieving acceptable performance for a fusion power system in the areas of economics, safety and environmental acceptability, is critically dependent on performance of the blanket and diverter systems which are the primary heat recovery, plasma purification, and tritium breeding systems. Tritium self-sufficiency must be maintained for a commercial power plant. The hybrid reactor is a combination of the fusion and fission processes. For self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. So working out the systematics of ( n, t) reaction cross-sections are of great importance for the definition of the excitation function character for the given reaction taking place on various nuclei at energies up to 20 MeV. In this study, we have calculated non-elastic cross-sections by using optical model for ( n, t) reactions at 14-15 MeV energy. We have investigated the excitation function character and reaction Q-values depending on the asymmetry term effect for the ( n, t) reaction cross-sections. We have obtained new coefficients for the ( n, t) reaction cross-sections. We have suggested semi-empirical formulas including optical model nonelastic effects by fitting two parameters for the ( n, t) reaction cross-sections at 14-15 MeV. We have discussed the odd-even effect and the pairing effect considering binding energy systematic of the nuclear shell model for the new experimental data and new cross-sections formulas ( n, t) reactions developed by Tel et al. We have determined a different parameter groups by the classification of nuclei into even-even, even-odd and odd-even for ( n, t) reactions cross-sections. The obtained cross-section formulas

  14. Study of activation cross-sections of deuteron induced reactions on rhodium up to 40 MeV

    NASA Astrophysics Data System (ADS)

    Ditrói, F.; Tárkányi, F.; Takács, S.; Hermanne, A.; Yamazaki, H.; Baba, M.; Mohammadi, A.; Ignatyuk, A. V.

    2011-09-01

    In the frame of a systematic study of the activation cross-sections of deuteron induced nuclear reactions, excitation functions of the 103Rh(d,x) 100,101,103Pd, 100g,101m,101g,102m,102gRh and 103gRu reactions were determined up to 40 MeV. Cross-sections were measured with the activation method using a stacked foil irradiation technique. Excitation functions of the contributing reactions were calculated using the ALICE-IPPE, EMPIRE-II and TALYS codes. From the measured cross-section data integral production yields were calculated and compared with experimental integral yield data reported in the literature. From the measured cross-sections and previous data, activation curves were deduced to support thin layer activation (TLA) on rhodium and Rh containing alloys.

  15. Measurement of the neutron-capture cross section on 63,65Cu between 0.4 and 7.5 MeV

    NASA Astrophysics Data System (ADS)

    Bray, Isabel; Bhike, Megha; Krishichayan, (None); Tornow, W.

    2015-10-01

    Copper is currently being used as a cooling and shielding material in most experimental searches for 0 ν β β decay. In order to accurately interpret background events in these experiments, the cross section of neutron-induced reactions on copper must be known. The purpose of this work was to measure the cross section of the 63,65Cu(n, γ)64,66Cu reactions. Data were collected through the activation method at a range of energies from approximately 0.4 MeV to 7.5 MeV, employing the neutron production reactions 3H(p,n)3Heand2H(d,n)3He. Previous data were limited to energies below approximately 3 MeV. The results are compared to predictions from the nuclear data libraries ENDF/B-VII.1 and TENDL-2014.

  16. Activation Cross-Sections for 14.2 MeV Neutrons on Molybdenum

    NASA Astrophysics Data System (ADS)

    Srinivasa Rao, C. V.; Lakshmana Das, N.; Thirumala Rao, B. V.; Rama Rao, J.

    1981-12-01

    Using the activation method, the cross-section for the following reactions on molybdenum were measured employing the mixed powder technique and Ge(Li) gamma-ray spectroscopy: 94Mo(n, 2n)93mMo, 3.5 ± 0.5 mbarn; 92Mo(n, 2n)91mMo, 19 ± 3 mbarn; 92Mo(n, 2n)91m+gMo, 226 ± 11 mbarn; 100Mo(n, p)100m2Nb, 9 ± 1 mbarn; 98Mo(n, p)98Nb, 10 ± 1 mbarn; 97Mo(n, p)97mNb, 5 ± 1 mbarn; 96Mo(n, p)96Nb, 12 ± 2 mbarn; 92Mo(n, α)89mZr, 2.1 ± 0.5 mbarn; and 92Mo(n, α)89m+gZr 24 ± 6 mbarn; the neutron energy was 14.2 ± 0.2 MeV. The experimental cross-sections were compared with the predictions of evaporation model and of different versions of pre-equilibrium model. The master equation approach appears to give satisfactory results.

  17. Determination of neutron capture cross sections of 232Th at 14.1 MeV and 14.8 MeV using the neutron activation method

    NASA Astrophysics Data System (ADS)

    Lan, Chang-Lin; Zhang, Yi; Lv, Tao; Xie, Bao-Lin; Peng, Meng; Yao, Ze-En; Chen, Jin-Gen; Kong, Xiang-Zhong

    2017-04-01

    The 232Th(n, γ)233Th neutron capture reaction cross sections were measured at average neutron energies of 14.1 MeV and 14.8 MeV using the activation method. The neutron flux was determined using the monitor reaction 27Al(n,α)24Na. The induced gamma-ray activities were measured using a low background gamma ray spectrometer equipped with a high resolution HPGe detector. The experimentally determined cross sections were compared with the data in the literature, and the evaluated data of ENDF/B-VII.1, JENDL-4.0u+, and CENDL-3.1. The excitation functions of the 232Th(n,γ)233Th reaction were also calculated theoretically using the TALYS1.6 computer code. Supported by Chinese TMSR Strategic Pioneer Science and Technology Project-The Th-U Fuel Physics Term (XDA02010100) and National Natural Science Foundation of China (11205076, 21327801)

  18. Photo-neutron reaction cross-sections for natMo in the bremsstrahlung end-point energies of 12-16 and 45-70 MeV

    NASA Astrophysics Data System (ADS)

    Naik, H.; Kim, G. N.; Kapote Noy, R.; Schwengner, R.; Kim, K.; Zaman, M.; Shin, S. G.; Gey, Y.; Massarczyk, R.; John, R.; Junghans, A.; Wagner, A.; Cho, M.-H.

    2016-07-01

    The natMo( γ, xn)90, 91, 99Mo reaction cross-sections were experimentally determined for the bremsstrahlung end-point energies of 12, 14, 16, 45, 50, 55, 60 and 70MeV by activation and off-line γ -ray spectrometric technique and using the 20MeV electron linac (ELBE) at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden, Germany, and the 100MeV electron linac at the Pohang Accelerator Laboratory (PAL), Pohang, Korea. The natMo( γ, xn)88, 89, 90, 91, 99Mo reaction cross-sections as a function of photon energy were also calculated using the computer code TALYS 1.6. The flux-weighted average cross-sections were obtained from the literature data and the calculated values of TALYS based on mono-energetic photons and are found to be in general agreement with the present results. The flux-weighted average experimental and theoretical cross-sections for the natMo( γ, xn)88, 89, 90, 91, 99Mo reactions increase with the bremsstrahlung end-point energy, which indicates the role of excitation energy. After a certain energy, the individual natMo( γ, xn) reaction cross-sections decrease with the increase of bremsstrahlung energy due to opening of other reactions, which indicates sharing of energy in different reaction channels. The 100Mo( γ, n) reaction cross-section is important for the production of 99Mo , which is a probable alternative to the 98Mo(n, γ) and 235U(n, f ) reactions.

  19. C$sup 12$(n,p) B$sup 12$ CROSS SECTION FOR 14.9- TO 17.5-MEV NEUTRONS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kreger, W.E.; Kern, B.D.

    1958-09-23

    The cross section for the C/sup 12/(n,p)B/sup 12/ reaction has been measured for 14.9- to 17.5-Mev nuetrons. The neutrons were obtained from the T(d,n)He/sup 4/ reaction and their flux density was determined by counting the recoil alpha particles or by counting the neutrons directly with a Li/sup 6/I(Eu) scintillation counter. A cylindrical plastic scintillator 5 inches in diameter and 3 inches in length served as the carbon-containing target and permitted the counting of the B/sup 12/ decay beta rays in nine consecutive 7-msec intervals during the beam-off period or a pulsed neutron beam cycle. The cross section rises from slightlymore » above the reaction threshold of 13.6-Mev to a value of 29.09 plus or minus 4.36 millibarns at 17.5 Mev. The B/sup 12/ beta decay half life has been redetermined as 18.87 plus or minus 0.50 milliseconds. (auth)« less

  20. Evaluation of cross sections for neutron-induced reactions in sodium. [10/sup -5/ eV to 20 MeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Larson, D.C.

    1980-09-01

    An evaluation of the neutron-induced cross sections of /sup 23/Na has been done for the energy range from 10/sup -5/ eV to 20 MeV. All significant cross sections are given, including differential cross sections for production of gamma rays. The recommended values are based on experimental data where available, and use results of a consistent model code analysis of available data to predict cross sections where there are no experimental data. This report describes the evaluation that was submitted to the Cross Section Evaluation Working Group (CSEWG) for consideration as a part of the Evaluated Nuclear Data File, Version V,more » and subsequently issued as MAT 1311. 126 references, 130 figures, 14 tables.« less

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

    DOE PAGES

    Ablikim, M.

    2015-11-28

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

  2. Neutron production cross sections for (d,n) reactions at 55 MeV

    NASA Astrophysics Data System (ADS)

    Wakasa, T.; Goto, S.; Matsuno, M.; Mitsumoto, S.; Okada, T.; Oshiro, H.; Sakaguchi, S.

    2017-08-01

    The cross sections for (d,n) reactions on {}^natC-{}^{197}Au have been measured at a bombarding energy of 55 MeV and a laboratory scattering angle of θ_lab = 9.5°. The angular distributions for the {}^natC(d,n) reaction have also been obtained at θ_lab = 0°-40°. The neutron energy spectra are dominated by deuteron breakup contributions and their peak positions can be reasonably reproduced by considering the Coulomb force effects. The data are compared with the TENDL-2015 nuclear data and Particle and Heavy Ion Transport code System (PHITS) calculations. Both calculations fail to reproduce the measured energy spectra and angular distributions.

  3. Extension of the energy range of experimental activation cross-sections data of deuteron induced nuclear reactions on indium up to 50MeV.

    PubMed

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

    2015-11-01

    The energy range of our earlier measured activation cross-sections data of longer-lived products of deuteron induced nuclear reactions on indium were extended from 40MeV up to 50MeV. The traditional stacked foil irradiation technique and non-destructive gamma spectrometry were used. No experimental data were found in literature for this higher energy range. Experimental cross-sections for the formation of the radionuclides (113,110)Sn, (116m,115m,114m,113m,111,110g,109)In and (115)Cd are reported in the 37-50MeV energy range, for production of (110)Sn and (110g,109)In these are the first measurements ever. The experimental data were compared with the results of cross section calculations of the ALICE and EMPIRE nuclear model codes and of the TALYS 1.6 nuclear model code as listed in the on-line library TENDL-2014. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Measurements of the 40Ar(n, γ)41Ar radiative-capture cross section between 0.4 and 14.8 MeV

    NASA Astrophysics Data System (ADS)

    Bhike, Megha; Fallin, B.; Tornow, W.

    2014-09-01

    The 40Ar(n, γ)41Ar neutron capture cross section has been measured between 0.4 and 14.8 MeV neutron energy using the activation technique. The data are important for estimating backgrounds in argon-based neutrino and dark-matter detectors and in the neutrino-less double-beta decay search GERDA, which uses liquid argon as cooling and shielding medium. For the first time the 40Ar(n, γ)41Ar cross section has been measured for neutron energies above 1 MeV. Our results are compared to the evaluation ENDF/B-VII.1 and the calculated prediction TENDL-2013. The latter agrees very well with the present results.

  5. Neutron-Induced Fission Cross Sections of 240Pu, 243Am, and natW in the Energy Range 1-200 MeV

    NASA Astrophysics Data System (ADS)

    Laptev, A. B.; Donets, A. Yu.; Dushin, V. N.; Fomichev, A. V.; Fomichev, A. A.; Haight, R. C.; Shcherbakov, O. A.; Soloviev, S. M.; Tuboltsev, Yu. V.; Vorobyev, A. S.

    2005-05-01

    A long-range research program devoted to measurements of neutron-induced fission cross-sections of actinides and stable isotopes is under way at the GNEIS facility. By now the new series of experiments for measurements of fission cross-section ratios relative to 235U has been completed for 240Pu, 243Am, and natW in a wide energy range of incident neutrons from 1 MeV to 200 MeV in the frame of the ISTC Project ♯1971. The measurements were performed using the multiplate ionization chamber and time-of-flight techniques. The results obtained in this measurement are presented in comparison with the other data.

  6. Charge-changing cross-section measurements of C-1612 at around 45 A MeV and development of a Glauber model for incident energies 10 A -2100 A MeV

    NASA Astrophysics Data System (ADS)

    Tran, D. T.; Ong, H. J.; Nguyen, T. T.; Tanihata, I.; Aoi, N.; Ayyad, Y.; Chan, P. Y.; Fukuda, M.; Hashimoto, T.; Hoang, T. H.; Ideguchi, E.; Inoue, A.; Kawabata, T.; Khiem, L. H.; Lin, W. P.; Matsuta, K.; Mihara, M.; Momota, S.; Nagae, D.; Nguyen, N. D.; Nishimura, D.; Ozawa, A.; Ren, P. P.; Sakaguchi, H.; Tanaka, J.; Takechi, M.; Terashima, S.; Wada, R.; Yamamoto, T.; RCNP-E372 Collaboration

    2016-12-01

    We have measured for the first time the charge-changing cross sections (σCC) of C-1612 on a 12C target at energies below 100 A MeV. To analyze these low-energy data, we have developed a finite-range Glauber model with a global parameter set within the optical-limit approximation which is applicable to reaction cross section (σR) and σCC measurements at incident energies from 10 A to 2100 A MeV. Adopting the proton-density distribution of 12C known from the electron-scattering data, as well as the bare total nucleon-nucleon cross sections and the real-to-imaginary-part ratios of the forward proton-proton elastic scattering amplitude available in the literatures, we determine the energy-dependent slope parameter βp n of the proton-neutron elastic differential cross section so as to reproduce the existing σR and interaction cross-section data for 12C+12C over a wide range of incident energies. The Glauber model thus formulated is applied to calculate the σR's of 12C on a 9Be and 27Al targets at various incident energies. Our calculations show excellent agreement with the experimental data. Applying our model to the σR and σCC for the so-called neutron-skin 16C nucleus, we reconfirm the importance of measurements at incident energies below 100 A MeV. The proton root-mean-square radii of C-1612 are extracted using the measured σCC's and the existing σR data. The results for C-1412 are consistent with the values from the electron scatterings, demonstrating the feasibility, usefulness of the σCC measurement, and the present Glauber model.

  7. Measurement of the 115In(n,γ)116 m In reaction cross-section at the neutron energies of 1.12, 2.12, 3.12 and 4.12 MeV

    NASA Astrophysics Data System (ADS)

    Lawriniang, Bioletty Mary; Badwar, Sylvia; Ghosh, Reetuparna; Jyrwa, Betylda; Vansola, Vibha; Naik, Haladhara; Goswami, Ashok; Naik, Yeshwant; Datrik, Chandra Shekhar; Gupta, Amit Kumar; Singh, Vijay Pal; Pol, Sudir Shibaji; Subramanyam, Nagaraju Balabenkata; Agarwal, Arun; Singh, Pitambar

    2015-08-01

    The 115In(n,γ)116 m In reaction cross section at neutron energies of 1.12, 2.12, 3.12 and 4.12 MeV was determined by using an activation and off-line γ-ray spectrometric technique. The monoenergetic neutron energies of 1.12 - 4.12 MeV were generated from the 7Li(p,n) reaction by using proton beam with energies of 3 and 4 MeV from the folded tandem ion beam accelerator (FOTIA) at Bhabha Atomic Research Centre (BARC) and with energies of 5 and 6 MeV from the Pelletron facility at Tata Institute of Fundamental Research (TIFR), Mumbai. The 197Au(n,γ)198Au reaction cross-section was used as the neutron flux monitor.The 115In(n,γ)116 m In reaction cross section at neutron energies of 1.12, 2.12, 3.12 and 4.12 MeV was determined by using an activation and off-line γ-ray spectrometric technique. The monoenergetic neutron energies of 1.12 - 4.12 MeV were generated from the 7Li(p,n) reaction by using proton beam with energies of 3 and 4 MeV from the folded tandem ion beam accelerator (FOTIA) at Bhabha Atomic Research Centre (BARC) and with energies of 5 and 6 MeV from the Pelletron facility at Tata Institute of Fundamental Research (TIFR), Mumbai. The 197Au(n,γ)198 Au reaction cross-section was used as the neutron flux monitor. The 115In(n,γ)116 m In reaction cross-sections at neutron energies of 1.12 - 4.12 MeV were compared with the literature data and were found to be in good agreement with one set of data, but not with others. The 115In(n,γ)116 m In cross-section was also calculated theoretically by using the computer code TALYS 1.6 and was found to be slightly lower than the experimental data from the present work and the literature.)198Au reaction cross-section was used as the neutron flux monitor. The 115In(n,γ)116 m In reaction cross-sections at neutron energies of 1.12 - 4.12 MeV were compared with the literature data and were found to be in good agreement with one set of data, but not with others. The 115In(n,γ)116 m In cross-section was also calculated

  8. Proton-nucleus total inelastic cross sections - An empirical formula for E greater than 10 MeV

    NASA Technical Reports Server (NTRS)

    Letaw, J. R.; Silberberg, R.; Tsao, C. H.

    1983-01-01

    An empirical formula for the total inelastic cross section of protons on nuclei with charge greater than 1 is presented. The formula is valid with a varying degree of accuracy down to proton energies of 10 MeV. At high energies (equal to or greater than 2 GeV) the formula reproduces experimental data to within reported errors (about 2%).

  9. A review of electron-nucleus bremsstrahlung cross sections between 1 and 10 MeV

    NASA Astrophysics Data System (ADS)

    Mangiarotti, A.; Martins, M. N.

    2017-12-01

    More than 80 years have passed since the first calculations of electron-nucleus bremsstrahlung cross sections were published by Sommerfeld, for non-relativistic electrons, and, independently, by Sauter, Bethe and Heitler, and Racah, for relativistic electrons. The Bethe-Heitler expression, that is based on the first Born approximation and includes the screening of the Coulomb field of the nucleus by the atomic electrons, has proven to work well at moderately high energies where the Landau-Pomeranchuk-Migdal effect is negligible. We review the current theoretical and experimental status with a highlight on electrons with kinetic energies between 1 and 10 MeV. The choice is motivated by the peculiar difficulties present in this energy region, where it is necessary to treat simultaneously the interaction with the Coulomb field beyond the first Born approximation and the effect of screening. A fully numerical approach within the S-matrix formalism has proven to be extremely difficult above a few MeV, because the number of partial waves needed for an accurate evaluation is prohibitively large. Here we focus on analytic results, including the more complex ones employing the Furry-Sommerfeld-Maue wave functions and taking into account the next-to-leading order, and discuss the advantages and limitations in light of the best available data. The influence of multiple scattering in the target is investigated under the actual experimental conditions. A comparison with the widely used cross section tabulations by Seltzer and Berger is also presented.

  10. 10B(n,α)7Li and 10B(n,α1γ)7Li cross section data up to 3 MeV incident neutron energy

    NASA Astrophysics Data System (ADS)

    Bevilacqua, Riccardo; Hambsch, Franz-Josef; Vidali, Marzio; Ruskov, Ivan; Lamia, Livio

    2017-09-01

    The 10B(n,α) reaction cross-section is a well-established neutron cross-section standard for incident neutron energies up to 1 MeV. However, above this energy limit there are only scarce direct (n,α) measurements available and these few experimental data are showing large inconsistencies with each other. These discrepancies are reflected in the evaluated data libraries: ENDF/B-VII.1, JEFF-3.1.2 and JENDL-4.0 are in excellent agreement up to 100 keV incident neutrons, whereas the 10B(n,α) data in the different libraries show large differences in the MeV region. To address these inconsistencies, we have measured the cross section of the two branches of the 10B(n,α) reaction for incident neutron energies up to 3 MeV. We present here the 10B(n,α) and the 10B(n,α1γ) reactions cross section data, their branching ratio and the total 10B(n,α) reaction cross section. The measurements were conducted with a dedicated Frisch-grid ionization chamber installed at the GELINA pulsed neutron source of the EC-JRC. We compare our results with existing experimental data and evaluations.

  11. Elastic and inelastic neutron scattering cross sections for 12C at En = 5.9, 6.1, and 7.0 MeV

    NASA Astrophysics Data System (ADS)

    Lyons, Elizabeth; Hicks, Sally; Morin, Theodore; Derdeyn, Elizabeth; Peters, Erin

    2017-09-01

    Measurements of neutron elastic and inelastic scattering differential cross sections from 12C have been performed at incident neutron energies of 5.9, 6.1, and 7.0 MeV. Comparisons of existing experimental cross sections (NNDC) at these incident neutron energies reveal large discrepancies. Accurate measurements of 12C cross sections are vital to facilitate precise calculations regarding criticality conditions for nuclear reactors, advances in security screening methods, and better understanding astrophysical and nuclear phenomenon. During preliminary measurements of 12C cross sections at the University of Kentucky Accelerator Laboratory (UKAL), we realized the relative efficiency of the deuterated benzene (main) detector was needed over an unusually large range of neutron energies due to the high Q value of the first excited state of 12C. Those experiments were repeated during the summer of 2017 to measure in situ the relative detector efficiency with better beam conditions and a better understanding of background observed from the 2H(d, n)3He source reaction. The resulting improved detector efficiency was used in determining the neutron elastic and inelastic scattering cross sections. While the former were found to be in excellent agreement with evaluated cross sections from ENDF, the latter show some discrepancies, especially at 6.1 MeV. Our results will be presented. Research is supported by USDOE-NNSA-SSAP: NA0002931, NSF: PHY-1606890, and the Donald A. Cowan Physics Institute at the University of Dallas.

  12. Mass spectra and fusion cross sections for /sup 20/Ne+/sup 24/Mg interaction at 55 and 85 MeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Grotowski, K.; Belery, P.; Delbar, T.

    1981-06-01

    Inclusive ..gamma.. spectra from the /sup 20/Ne+/sup 24/Mg interaction have been measured using 55- and 85-MeV /sup 20/Ne ions. The identification of ..gamma.. lines allows the determination of mass spectra in the region 12< or =A< or =43. Experimental results are compared with statistical model calculations. The total reaction and fusion cross sections are extracted. Cross sections for inelastic scattering, few nucleon transfers, and deep inelastic scattering are estimated.

  13. A new measurement of the 6Li(n, α)t cross section at MeV energies using a 252Cf fission chamber and 6Li scintillators

    NASA Astrophysics Data System (ADS)

    Kirsch, Leo E.; Devlin, M.; Mosby, S. M.; Gomez, J. A.

    2017-12-01

    A new measurement is presented of the 6Li(n, α)t cross section from 245 keV to 10 MeV using a 252Cf fission chamber with 6LiI(Eu) and Cs2LiYCl6:Ce (CLYC) scintillators which act as both target and detector. Neutron energies are determined from the time of flight (TOF) method using the signals from spontaneous fission and reaction product recoil. Simulations of neutron downscatter in the crystals and fission chamber bring 6Li(n, α)t cross section values measured with the 6LiI(Eu) into agreement with previous experiments and evaluations, except for two resonances at 4.2 and 6.5 MeV introduced by ENDF/B-VII.1. Suspected neutron transport modeling issues cause the cross section values obtained with CLYC to be discrepant above 2 MeV.

  14. Total reaction cross sections and neutron-removal cross sections of neutron-rich light nuclei measured by the COMBAS fragment-separator

    NASA Astrophysics Data System (ADS)

    Hue, B. M.; Isataev, T.; Erdemchimeg, B.; Artukh, A. G.; Aznabaev, D.; Davaa, S.; Klygin, S. A.; Kononenko, G. A.; Khuukhenkhuu, G.; Kuterbekov, K.; Lukyanov, S. M.; Mikhailova, T. I.; Maslov, V. A.; Mendibaev, K.; Sereda, Yu M.; Penionzhkevich, Yu E.; Vorontsov, A. N.

    2017-12-01

    Preliminary results of measurements of the total reaction cross sections σR and neutron removal cross section σ-xn for weakly bound 6He, 8Li, 9Be and 10Be nuclei at energy range (20-35) A MeV with 28Si target is presented. The secondary beams of light nuclei were produced by bombardment of the 22Ne (35 A MeV) primary beam on Be target and separated by COMBAS fragment-separator. In dispersive focal plane a horizontal slit defined the momentum acceptance as 1% and a wedge degrader of 200 μm Al was installed. The Bρ of the second section of the fragment-separator was adjusted for measurements in energy range (20-35) A MeV. Two-neutron removal cross sections for 6He and 10Be and one -neutron removal cross sections 8Li and 9Be were measured.

  15. Stopping cross sections for 0.25-3.0-MeV He-4 ions in cadmium sulfide

    NASA Technical Reports Server (NTRS)

    Miller, W. E.; Hutchby, J. A.

    1975-01-01

    Stopping cross sections of He-4 ions with energies between 0.25 and 3.0 MeV have been measured for cadmium sulfide with a probable error of plus or minus 7% to 8%. The experimental method utilized the Rutherford backscattering technique and measured the energy loss of elastically scattered He-4 ions from films of cadmium sulfide sputtered on carbon substrates. The experimental data are compared with recent experimental and theoretical results.

  16. Neutron capture cross-section measurements for 238U between 0.4 and 1.4 MeV

    NASA Astrophysics Data System (ADS)

    Krishichayan, Fnu; Finch, S. W.; Howell, C. R.; Tonchev, A. P.; Tornow, W.

    2017-09-01

    Neutron-induced radiative-capture cross-section data of 238U are crucial for fundamental nuclear physics as well as for Stewardship Science, for advanced-fuel-cycle calculations, and for nuclear astrophysics. Based on different techniques, there are a large number of 238U(n, γ) 239U cross-section data available in the literature. However, there is a lack of systematic and consistent measurements in the 0.1 to 3.0 MeV energy range. The goal of the neutron-capture project at TUNL is to provide accurate 238U(n, γ) 239U cross-section data in this energy range. The 238U samples, sandwiched between gold foils of the same size, were irradiated for 8-14 hours with monoenergetic neutrons. To avoid any contribution from thermal neutrons, the 238U and 197Au targets were placed inside of a thin-walled pill-box made of 238U. Finally, the whole pill-box was wrapped in a gold foil as well. After irradiation, the samples were gamma-counted at the TUNL's low-background counting facility using high-efficient HPGe detectors. The 197Au monitor foils were used to calculate the neutron flux. The experimental technique and 238U(n, γ) 239U cross-section results at 6 energies will be discussed during the meeting.

  17. 197Au(n ,2 n ) reaction cross section in the 15-21 MeV energy range

    NASA Astrophysics Data System (ADS)

    Kalamara, A.; Vlastou, R.; Kokkoris, M.; Nicolis, N. G.; Patronis, N.; Serris, M.; Michalopoulou, V.; Stamatopoulos, A.; Lagoyannis, A.; Harissopulos, S.

    2018-03-01

    The cross section of the 197Au(n ,2 n )196Au reaction has been determined at six energies ranging from 15.3-20.9 MeV by means of the activation technique, relative to the 27Al(n ,α )24Na reaction. Quasimonoenergetic neutron beams were produced via the 3H(d ,n )4He reaction at the 5.5 MV Tandem T11/25 accelerator laboratory of NCSR "Demokritos". After the irradiations, the induced γ -ray activity of the target and reference foils was measured with high-resolution HPGe detectors. The cross section for the high spin isomeric state (12-) was determined along with the sum of the ground (2-), the first (5+), and second (12-) isomeric states. Theoretical calculations were carried out with the codes empire 3.2.2 and talys 1.8. Optimum input parameters were chosen in such a way as to simultaneously reproduce several experimental reaction channel cross sections in a satisfactory way, namely the (n ,elastic ), (n ,2 n ), (n ,3 n ), (n ,p ), (n ,α ), and (n ,total) ones.

  18. Evaluated cross-section libraries and kerma factors for neutrons up to 100 MeV on {sup 12}C

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chadwick, M.B.; Blann, M.; Cox, L.

    1995-04-11

    A program is being carried out at Lawrence Livermore National Laboratory to develop high-energy evaluated nuclear data libraries for use in Monte Carlo simulations of cancer radiation therapy. In this report we describe evaluated cross sections and kerma factors for neutrons with incident energies up to 100 MeV on {sup 12}C. The aim of this effort is to incorporate advanced nuclear physics modeling methods, with new experimental measurements, to generate cross section libraries needed for an accurate simulation of dose deposition in fast neutron therapy. The evaluated libraries are based mainly on nuclear model calculations, benchmarked to experimental measurements wheremore » they exist. We use the GNASH code system, which includes Hauser-Feshbach, preequilibrium, and direct reaction mechanisms. The libraries tabulate elastic and nonelastic cross sections, angle-energy correlated production spectra for light ejectiles with A{le}and kinetic energies given to light ejectiles and heavy recoil fragments. The major steps involved in this effort are: (1) development and validation of nuclear models for incident energies up to 100 MeV; (2) collation of experimental measurements, including new results from Louvain-la-Nueve and Los Alamos; (3) extension of the Livermore ENDL formats for representing high-energy data; (4) calculation and evaluation of nuclear data; and (5) validation of the libraries. We describe the evaluations in detail, with particular emphasis on our new high-energy modeling developments. Our evaluations agree well with experimental measurements of integrated and differential cross sections. We compare our results with the recent ENDF/B-VI evaluation which extends up to 32 MeV.« less

  19. Systematic measurement of double-differential neutron production cross sections for deuteron-induced reactions at an incident energy of 102 MeV

    NASA Astrophysics Data System (ADS)

    Araki, Shouhei; Watanabe, Yukinobu; Kitajima, Mizuki; Sadamatsu, Hiroki; Nakano, Keita; Kin, Tadahiro; Iwamoto, Yosuke; Satoh, Daiki; Hagiwara, Masayuki; Yashima, Hiroshi; Shima, Tatsushi

    2017-01-01

    Double-differential neutron production cross sections (DDXs) for deuteron-induced reactions on Li, Be, C, Al, Cu, and Nb at 102 MeV were measured at forward angles ≤25° by means of a time of flight (TOF) method with NE213 liquid organic scintillators at the Research Center of Nuclear Physics (RCNP), Osaka University. The experimental DDXs and energy-integrated cross sections were compared with TENDL-2015 data and Particle and Heavy Ion Transport code System (PHITS) calculation using a combination of the KUROTAMA model, the Liege Intra-Nuclear Cascade model, and the generalized evaporation model. The PHITS calculation showed better agreement with the experimental results than TENDL-2015 for all target nuclei, although the shape of the broad peak around 50 MeV was not satisfactorily reproduced by the PHITS calculation.

  20. Measurements of the 169Tm(n,2n)168Tm cross section between 9.0 and 17.5 MeV

    NASA Astrophysics Data System (ADS)

    Soter, J.; Bhike, Megha; Krishichayan, Fnu; Finch, S. W.; Tornow, W.

    2016-09-01

    Measurements of the 169Tm(n,2n)168Tm cross section have been performed in 0.5 MeV intervals for neutron energies ranging from 9.0 MeV to 17.5 MeV in order to resolve discrepancies in the current literature data. The neutron activation technique was used with 90Zr and 197Au as monitor foils. After irradiation, de-excitation gamma rays were recorded off-line with High-Purity Germanium (HPGE) detectors in TUNL's Low-Background Counting Facility. In addition, data for the 169Tm(n,3n)167Tm reaction have also been obtained from 15.5 MeV to 17.5 MeV. The results of these measurements provide the basis for investigating properties of the interial confinement fusion plasma in deuterium-tritium (DT) capsules at the National Ignition Facility located at Lawrence Livermore National Laboratory.

  1. Proton-impact ionization cross sections of adenine measured at 0.5 and 2.0 MeV by electron spectroscopy

    NASA Astrophysics Data System (ADS)

    Iriki, Y.; Kikuchi, Y.; Imai, M.; Itoh, A.

    2011-11-01

    Double-differential ionization cross sections (DDCSs) of vapor-phase adenine molecules (C5H5N5) by 0.5- and 2.0-MeV proton impact have been measured by the electron spectroscopy method. Electrons ejected from adenine were analyzed by a 45∘ parallel-plate electrostatic spectrometer over an energy range of 1.0-1000 eV at emission angles from 15∘ to 165∘. Single-differential cross sections (SDCSs) and total ionization cross sections (TICSs) were also deduced. It was found from the Platzman plot, defined as SDCSs divided by the classical Rutherford knock-on cross sections per target electron, that the SDCSs at higher electron energies are proportional to the total number of valence electrons (50) of adenine, while those at low-energy electrons are highly enhanced due to dipole and higher-order interactions. The present results of TICS are in fairly good agreement with recent classical trajectory Monte Carlo calculations, and moreover, a simple analytical formula gives nearly equivalent cross sections in magnitude at the incident proton energies investigated.

  2. Measurements of the (n,2n) Reaction Cross Section of 181Ta from 8 to 15 MeV

    NASA Astrophysics Data System (ADS)

    Bhatia, C.; Gooden, M. E.; Tornow, W.; Tonchev, A. P.

    2014-05-01

    The cross section for the reaction 181Ta(n,2n)180Tag was measured from 8 to 15 MeV in small energy steps to resolve inconsistencies in the existing databases. The activation technique was used, and the 93.4 keV γ-ray from the decay of the 180Tag ground state was recorded with a HPGe detector. In addition, the γ-rays from the monitor reactions 27Al(n,α)24Na and 197Au(n,2n)196Au were measured for neutron fluence determination. As a cross check, a calibrated neutron detector was also used. The ENDF/B-VII.1 and TENDL-2011 evaluations are in considerable disagreement with the present data, which in turn agree very well with the majority of the existing data in the 14 MeV energy region.

  3. Calculation and analysis of cross-sections for p+184W reactions up to 200 MeV

    NASA Astrophysics Data System (ADS)

    Sun, Jian-Ping; Zhang, Zheng-Jun; Han, Yin-Lu

    2015-08-01

    A set of optimal proton optical potential parameters for p+ 184W reactions are obtained at incident proton energy up to 250 MeV. Based on these parameters, the reaction cross-sections, elastic scattering angular distributions, energy spectra and double differential cross sections of proton-induced reactions on 184W are calculated and analyzed by using theoretical models which integrate the optical model, distorted Born wave approximation theory, intra-nuclear cascade model, exciton model, Hauser-Feshbach theory and evaporation model. The calculated results are compared with existing experimental data and good agreement is achieved. Supported by National Basic Research Program of China, Technology Research of Accelerator Driven Sub-critical System for Nuclear Waste Transmutation (2007CB209903) and Strategic Priority Research Program of Chinese Academy of Sciences, Thorium Molten Salt Reactor Nuclear Energy System (XDA02010100)

  4. Non-Rutherford cross-sections for alpha elastic scattering off Z = 28-38 elements in the energy range up to 10 MeV

    NASA Astrophysics Data System (ADS)

    Gurbich, A. F.; Bokhovko, M. V.

    2018-04-01

    The alpha elastic scattering cross-sections for Ni, Cu, and Y were measured at the energies above the onset of the non-Rutherford scattering. The obtained experimental data along with data from literature were incorporated into the theoretical analysis in the framework of the optical model. The optimization of the model parameters provided a basis for the calculations of the differential cross-sections for Z = 28-38 elements in the energy range up to 10 MeV. The obtained cross sections were made available for common use through the SigmaCalc web site at http://sigmacalc.iate.obninsk.ru/.

  5. L-shell x-ray production cross sections in Nd, Gd, Ho, Yb, Au and Pb for 25-MeV carbon and 32-MeV oxygen ions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Andrews, M.C.; McDaniel, F.D.; Duggan, J.L.

    1984-01-01

    L-shell x-ray production cross sections in /sub 60/Nd, /sub 64/Gd, /sub 67/Ho, /sub 70/Yb, /sub 79/Au and /sub 82/Pb have been measured for incident 25 MeV /sub 6//sup 12/C/sup +q/(q = 4,5,6) and 32 MeV /sub 8//sup 16/O/sup +q/(q = 5,7,8) ions. Measurements were made on targets ranging in thickness from 1 to 100 ..mu..g/cm/sup 2/. Echancement in the L-shell x-ray production cross section for projectiles with one or two K-shell vacancies over those for projectiles with no K-shell vacancies is observed. The sum of direct ionization to the continuum (DI) plus electron capture (EC) to the L,M,N ... shellsmore » and EC to the K-shell of the projectile have been extracted from the data. Calculations in the first Born approximation are approx. 10 times larger than the data. Predictions of the ECPSSR theory that accounts for the energy-loss, Coulomb deflection, perturbed-stationary state, and relativistic effects are in good agreement with the data for both ions.« less

  6. Activation cross section and isomeric cross section ratios for the (n ,2 n ) reaction on 153Eu

    NASA Astrophysics Data System (ADS)

    Luo, Junhua; Jiang, Li; Li, Suyuan

    2017-10-01

    The 153Eu(n ,2 n ) m1,m2,g152Eu cross section was measured by means of the activation technique at three neutron energies in the range 13-15 MeV. The quasimonoenergetic neutron beam was formed via the 3H(d ,n ) 4He reaction, in the Pd-300 Neutron Generator at the Chinese Academy of Engineering Physics (CAEP). The activities induced in the reaction products were measured using high-resolution γ-ray spectroscopy. The cross section of the population of the second high-spin (8-) isomeric state was measured along with the reaction cross section populating both the ground (3-) and the first isomeric state (0-). Cross sections were also evaluated theoretically using the numerical code TALYS-1.8, with different level density options at neutron energies varying from the reaction threshold to 20 MeV. Results are discussed and compared with the corresponding literature.

  7. Calculation of SF6-/SF6 and Cl-/CFCl3 electron attachment cross sections in the energy range 0-100 meV

    NASA Technical Reports Server (NTRS)

    Chutjian, A.

    1982-01-01

    Electron attachment cross sections for the processes SF6-/SF6 and Cl-/CFCl3 are calculated in a local theory using a model in which diatomic-like potential energy curves for the normal modes are constructed from available spectroscopic data. Thermally populated vibrational and rotational levels are included. Good agreement is found with experimental cross sections in the energy range 5-100 meV for a particular choice of potential energy curve parameters.

  8. Activation cross section and isomeric cross-section ratio for the 151Eu(n,2n)150m,gEu process

    NASA Astrophysics Data System (ADS)

    Luo, Junhua; Li, Suyuan; Jiang, Li

    2018-07-01

    The cross sections of 151Eu(n,2n)150m,gEu reactions and their isomeric cross section ratios σm/σt have been measured experimentally. Cross sections are measured, relative to a reference 93Nb(n,2n)92mNb reaction cross section, by means of the activation technique at three neutron energies 13.5, 14.1, and 14.8 MeV. Monoenergetic neutron beams were formed via the 3H(d,n)4He reaction and both Eu2O3 samples and Nb monitor foils were activated together to determine the reaction cross section and the incident neutron flux. The activities induced in the reaction products were measured using high-resolution gamma ray spectroscopy. Cross sections were also evaluated theoretically using the numerical nuclear model code, TALYS-1.8 with different level density options at neutron energies varying from the reaction threshold to 20 MeV. Results are discussed and compared with the corresponding literature.

  9. Activation cross section and isomeric cross section ratio for the 76Ge(n,2n)75m,gGe process

    NASA Astrophysics Data System (ADS)

    Luo, Junhua; Jiang, Li; Wang, Xinxing

    2018-04-01

    We measured neutron-induced reaction cross sections for the 76Ge(n,2n)75m,gGe reactions and their isomeric cross section ratios σm/σg at three neutron energies between 13 and 15MeV by an activation and off-line γ-ray spectrometric technique using the K-400 Neutron Generator at the Chinese Academy of Engineering Physics (CAEP). Ge samples and Nb monitor foils were activated together to determine the reaction cross section and the incident neutron flux. The monoenergetic neutron beams were formed via the 3H( d, n)4He reaction. The pure cross section of the ground state was derived from the absolute cross section of the metastable state and the residual nuclear decay analysis. The cross sections were also calculated using the nuclear model code TALYS-1.8 with different level density options at neutron energies varying from the reaction threshold to 20MeV. Results are discussed and compared with the corresponding literature data.

  10. Measurements of the 169Tm(n ,2 n )168Tm cross section from threshold to 15 MeV

    NASA Astrophysics Data System (ADS)

    Soter, J.; Bhike, M.; Finch, S. W.; Krishichayan, Tornow, W.

    2017-12-01

    Measurements of the 169Tm(n ,2 n )168Tm cross section have been performed via the activation technique at 13 energies between 8.5 and 15.0 MeV. The purpose of this comprehensive data set is to provide an alternative diagnostic tool for obtaining subtle information on the neutron energy distribution produced in inertial confinement deuterium-tritium fusion experiments at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. The 169Tm(n ,2 n )168Tm reaction not only provides the primary 14-MeV neutron fluence, but also the important down-scattered neutron fluence, the latter providing information on the density achieved in the deuterium-tritium plasma during a laser shot.

  11. Measurements of the Tm 169 ( n , 2 n ) Tm 168 cross section from threshold to 15 MeV

    DOE PAGES

    Soter, J.; Bhike, M.; Finch, S. W.; ...

    2017-12-27

    Measurements of the 169Tm(n,2n) 168Tm cross section have been performed via the activation technique at 13 energies between 8.5 and 15.0 MeV. The purpose of this comprehensive data set is to provide an alternative diagnostic tool for obtaining subtle information on the neutron energy distribution produced in inertial confinement deuterium-tritium fusion experiments at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. In conclusion, the 169Tm(n,2n) 168Tm reaction not only provides the primary 14-MeV neutron fluence, but also the important down-scattered neutron fluence, the latter providing information on the density achieved in the deuterium-tritium plasma during a laser shot.

  12. Neutron-capture cross-section measurements of Xe136 between 0.4 and 14.8 MeV

    NASA Astrophysics Data System (ADS)

    Bhike, Megha; Tornow, W.

    2014-03-01

    Fast-neutron-capture cross-section data on Xe136 have been measured with the activation method between 0.4 and 14.8 MeV. The cross section was found to be of the order of 1 mb at the eleven energies investigated. This result is important to interpret potential neutron-induced backgrounds in the enriched xenon observatory and KamLAND-Zen neutrinoless double-β decay searches that use xenon as both source and detector. A high-pressure sphere filled with Xe136 was irradiated with monoenergetic neutrons produced by the reactions 3H(p ,n)3He, 2H(d ,n)3He, and 3H(d ,n)4He. Indium and gold monitor foils were irradiated simultaneously with the Xe136 to determine the incident neutron flux. The activities of the reaction products were measured with high-resolution γ-ray spectroscopy. The present results are compared to predictions from ENDF/B-VII.1 and TENDL-2012.

  13. Photofission cross-section ratio measurement of 235U/238U using monoenergetic photons in the energy range of 9.0-16.6 MeV

    NASA Astrophysics Data System (ADS)

    Krishichayan; Bhike, Megha; Finch, S. W.; Howell, C. R.; Tonchev, A. P.; Tornow, W.

    2017-05-01

    Photofission cross-section ratios of 235U and 238U have been measured using monoenergetic photon beams at the HIγS facility of TUNL. These measurements have been performed in small energy steps between 9.0 and 16.6 MeV using a dual-fission ionization chamber. Measured cross-section ratios are compared with the previous experimental data as well as with the recent evaluated nuclear data library ENDF.

  14. Calculation of proton total reaction cross sections for some target nuclei in incident energy range of 10-600 MeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bueyuekuslu, H.; Kaplan, A., E-mail: kaplan@fef.sdu.edu.t; Aydin, A.

    2010-10-15

    In this study, proton total reaction cross sections have been investigated for some isotopes such as {sup 12}C, {sup 27}Al, {sup 9}Be, {sup 16}O, {sup 181}Ta, {sup 197}Au, {sup 6}Li, and {sup 14}N by a proton beam up to 600 MeV. Calculation of the proton total cross sections has been carried out by the analytic expression formulated by M.A. Alvi by using Coulomb-modified Glauber theory with the Helm model nuclear form factor. The obtained results have been discussed and compared with the available experimental data and found to be in agreement with each other.

  15. A new measurement of the 6Li(n,α)t cross section at MeV energies using a 252Cf fission chamber and 6Li scintillators

    DOE PAGES

    Kirsch, Leo Edward; Devlin, Matthew James; Mosby, Shea Morgan; ...

    2017-09-01

    We present a new measurement of the 6Li(n,α)t cross section from 245 keV to 10 MeV using a 252Cf fission chamber with 6LiI(Eu) and Cs 2LiYCl 6:Ce (CLYC) scintillators which act as both target and detector. Neutron energies are determined from the time of flight (TOF) method using the signals from spontaneous fission and reaction product recoil. Simulations of neutron downscatter in the crystals and fission chamber bring 6Li(n,α)t cross section values measured with the 6LiI(Eu) into agreement with previous experiments and evaluations, except for two resonances at 4.2 and 6.5 MeV introduced by ENDF/B-VII.1. Suspected neutron transport modeling issuesmore » cause the cross section values obtained with CLYC to be discrepant above 2 MeV.« less

  16. A new measurement of the 6Li(n,α)t cross section at MeV energies using a 252Cf fission chamber and 6Li scintillators

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kirsch, Leo Edward; Devlin, Matthew James; Mosby, Shea Morgan

    We present a new measurement of the 6Li(n,α)t cross section from 245 keV to 10 MeV using a 252Cf fission chamber with 6LiI(Eu) and Cs 2LiYCl 6:Ce (CLYC) scintillators which act as both target and detector. Neutron energies are determined from the time of flight (TOF) method using the signals from spontaneous fission and reaction product recoil. Simulations of neutron downscatter in the crystals and fission chamber bring 6Li(n,α)t cross section values measured with the 6LiI(Eu) into agreement with previous experiments and evaluations, except for two resonances at 4.2 and 6.5 MeV introduced by ENDF/B-VII.1. Suspected neutron transport modeling issuesmore » cause the cross section values obtained with CLYC to be discrepant above 2 MeV.« less

  17. Investigation of activation cross-sections of deuteron induced reactions on vanadium up to 40 MeV

    NASA Astrophysics Data System (ADS)

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

    2011-08-01

    Experimental excitation functions for deuteron induced reactions up to 40 MeV on natural vanadium were measured with the activation method using a stacked foil irradiation technique. From high resolution gamma spectrometry cross-section data for the production of 51Cr, 48V, 48,47,46Sc and 47Ca were determined. Comparisons with the earlier published data are presented and results for values predicted by different theoretical codes are included. Thick target yields were calculated from a fit to our experimental excitation curves and compared with the earlier experimental data. Depth distribution curves used for thin layer activation (TLA) are also presented.

  18. L-shell x-ray production cross sections of Ni, Cu, Ge, As, Rb, Sr, Y, Zr, and Pd by (0. 25--2. 5)-MeV protons

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Duggan, J.L.; Kocur, P.M.; Price, J.L.

    1985-10-01

    L-shell x-ray production cross sections by /sub 1//sup 1/H/sup +/ ions are reported. The data are compared to the first Born approximation (plane-wave Born approximation for direct ionization and Oppenheimer-Brinkman-Kramers approximation for electron capture) and to the ECPSSR (energy-loss and Coulomb-deflection effects, perturbed stationary-state approximation with relativistic correction) theory. The energy of the protons ranged from 0.25 to 2.5 MeV in steps of 0.25 MeV. The targets used in these measurements were /sub 28/Ni, /sub 29/Cu, /sub 32/Ge, /sub 33/As, /sub 37/Rb, /sub 38/Sr, /sub 39/Y, /sub 40/Zr, and /sub 46/Pd. The first Born theory generally agrees with the datamore » found in the literature at high energies and overpredicts them below 1.5 MeV. The ECPSSR predictions are in better agreement with experimental cross sections. At 0.25 MeV our data, however, are underestimated by this theory and tend to agree with the first Born approximation.« less

  19. Experimental cross-sections for proton induced nuclear reactions on mercury up to 65 MeV

    NASA Astrophysics Data System (ADS)

    Hermanne, A.; Tárkányi, F.; Takács, S.; Ditrói, F.; Szücs, Z.; Brezovcsik, K.

    2016-07-01

    Cross-sections for formation of activation products induced by protons on natural mercury targets were measured. Results for 196m,196g,197g(cum), 198m,198g,199g(cum), 200g(cum), 201,202Tl, 194g(cum), 195g(cum), 196g(cum), 198m,199g(cum) Au and 195m,197m,203Hg are presented up to 65 MeV incident particle energy, many of these for the first time. The experimental data are compared with literature values and with the predictions of the TALYS 1.6 code (results taken from TENDL-2015 on-line library), thick target yields were derived and possible applications in biomedical sciences are discussed.

  20. Measurement of cross sections for the 147Sm(n, alpha)144Nd reaction at 5.0 and 6.0 MeV.

    PubMed

    Zhang, Guohui; Zhang, Jiaguo; Guo, Li'an; Wu, Hao; Chen, Jinxiang; Tang, Guoyou; Gledenov, Yu M; Sedysheva, M V; Khuukhenkhuu, G; Szalanski, P J

    2009-01-01

    Cross sections of the (147)Sm(n, alpha)(144)Nd reaction were measured at En=5.0 and 6.0MeV. A twin gridded ionization chamber was used as a charged particle detector and two large area (147)Sm(2)O(3) samples placed back to back were employed. Experiments were performed at the 4.5MV Van de Graaff accelerator of Peking University. Neutrons were produced through the D(d, n)(3)He reaction with a deuterium gas target. Absolute neutron flux was determined by a small (238)U fission chamber. Present cross-section data are compared with existing results of evaluations and measurements.

  1. Cross sections for production of the 15.10 MeV and other astrophysically significant gamma-ray lines through excitation and spallation of sup 12 C and sup 16 O with protons

    NASA Technical Reports Server (NTRS)

    Lang, F. L.; Werntz, C. W.; Crannell, C. J.; Trombka, J. I.; Chang, C. C.

    1986-01-01

    The ratio of the flux of 15.10-MeV gamma rays to the flux of 4.438-MeV gamma rays resulting from excitation of the corresponding states in C-12 as a sensitive measure of the spectrum of the exciting particles produced in solar flares and other cosmic sources. These gamma rays are produced predominantly by interactions with C-12 and O-16, both of which are relatively abundant in the solar photosphere. Gamma ray production cross sections for proton interactions have been reported previously for all important channels except for the production of 15.10-MeV gamma rays from O-16. The first reported measurement of the 15.10-MeV gamma ray production cross section from p + O-16 is presented here. The University of Maryland cyclotron was employed to produce 40-, 65-, and 86-MeV protons which interacted with CH2 and BeO targets. The resultant gamma ray spectra were measured with a high-purity germanium semiconductor detector at 70, 90, 110, 125, and 140 degrees relative to the direction of the incident beam for each proton energy. Other gamma ray lines resulting from direct excitation and spallation reactions with C-12 and 0-16 were observed as well, and their gamma ray production cross sections described.

  2. 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.

    PubMed

    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.

  3. Measurement of the normalized 238U(n ,f )/235U(n ,f ) cross section ratio from threshold to 30 MeV with the NIFFTE fission Time Projection Chamber

    NASA Astrophysics Data System (ADS)

    Casperson, R. J.; Asner, D. M.; Baker, J.; Baker, R. G.; Barrett, J. S.; Bowden, N. S.; Brune, C.; Bundgaard, J.; Burgett, E.; Cebra, D. A.; Classen, T.; Cunningham, M.; Deaven, J.; Duke, D. L.; Ferguson, I.; Gearhart, J.; Geppert-Kleinrath, V.; Greife, U.; Grimes, S.; Guardincerri, E.; Hager, U.; Hagmann, C.; Heffner, M.; Hensle, D.; Hertel, N.; Higgins, D.; Hill, T.; Isenhower, L. D.; King, J.; Klay, J. L.; Kornilov, N.; Kudo, R.; Laptev, A. B.; Loveland, W.; Lynch, M.; Lynn, W. S.; Magee, J. A.; Manning, B.; Massey, T. N.; McGrath, C.; Meharchand, R.; Mendenhall, M. P.; Montoya, L.; Pickle, N. T.; Qu, H.; Ruz, J.; Sangiorgio, S.; Schmitt, K. T.; Seilhan, B.; Sharma, S.; Snyder, L.; Stave, S.; Tate, A. C.; Tatishvili, G.; Thornton, R. T.; Tovesson, F.; Towell, D. E.; Towell, R. S.; Walsh, N.; Watson, S.; Wendt, B.; Wood, L.; Yao, L.; Younes, W.; Niffte Collaboration

    2018-03-01

    The normalized 238U(n ,f )/235U(n ,f ) cross section ratio has been measured using the NIFFTE fission Time Projection Chamber (fissionTPC) from the reaction threshold to 30 MeV . The fissionTPC is a two-volume MICROMEGAS time projection chamber that allows for full three-dimensional reconstruction of fission-fragment ionization profiles from neutron-induced fission. The measurement was performed at the Los Alamos Neutron Science Center, where the neutron energy is determined from neutron time of-flight. The 238U(n ,f )/235U(n ,f ) ratio reported here is the first cross section measurement made with the fissionTPC, and will provide new experimental data for evaluation of the 238U(n ,f ) cross section, an important standard used in neutron-flux measurements. Use of a development target in this work prevented the determination of an absolute normalization, to be addressed in future measurements. Instead, the measured cross section ratio has been normalized to ENDF/B-VIII.β 5 at 14.5 MeV.

  4. Experiments on Antiprotons: Antiproton-Nucleon Cross Sections

    DOE R&D Accomplishments Database

    Chamberlain, Owen; Keller, Donald V.; Mermond, Ronald; Segre, Emilio; Steiner, Herbert M.; Ypsilantis, Tom

    1957-07-22

    In this paper experiments are reported on annihilation and scattering of antiprotons in H{sub 2}O , D{sub 2}O, and O{sub 2}. From the data measured it is possible to obtain an antiproton-proton and an antiproton-deuteron cross section at 457 Mev (lab). Further analysis gives the p-p and p-n cross sections as 104 mb for the p-p reaction cross section and 113 mb for the p-n reaction cross section. The respective annihilation cross sections are 89 and 74 mb. The Glauber correction necessary in order to pass from the p-d to the p-n cross section by subtraction of the p-p cross section is unfortunately large and somewhat uncertain. The data are compared with the p-p and p-n cross sections and with other results on p-p collisions.

  5. Neutron-induced fission-cross-section measurements and calculations of selected transplutonic isotopes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    White, R.M.; Browne, J.C.

    1982-08-27

    The neutron-induced fission cross sections of /sup 242m/Am and /sup 245/Cm have been measured over an energy range of 10/sup -4/ eV to approx. 20 MeV in a series of experiments at three facilities during the past several years. The combined results of these measurements, in which only sub-milligram quantities of enriched isotopes were used, yield cross sections with uncertainties of approximately 5% below 10 MeV relative to the /sup 235/U standard cross section used to normalize the data. We summarize the resonance analysis of the /sup 242m/Am(n,f) cross section in the eV region. Hauser-Feshbach statistical calculations of the detailedmore » fission cross sections of /sup 235/U and /sup 245/Cm have been carried out over the energy region from 0.1 to 5 MeV and these results are compared with our experimental data.« less

  6. Cross Section Measurement for the 95Mo(n, {alpha})92Zr Reaction at 4.0, 5.0 and 6.0 MeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Guohui; Wu, Hao; Zhang, Jiaguo

    2011-01-01

    For the {sup 95}Mo(n, {alpha}){sup 92}Zr reaction cross section, there is only one experimental datum in the MeV neutron energy region with large uncertainty. As a result, very large deviations exist in different evaluated nuclear data libraries. This paper report the measurement of cross sections of the {sup 95}Mo(n, {alpha}){sup 92}Zr reaction at En = 4.0, 5.0 and 6.0 MeV. Experiments were performed at the 4.5 MV Van de Graaff of Peking University, China. A twin gridded ionization chamber was used as alpha particle detector and two large area {sup 95}Mo samples placed back to back were adopted. Fast neutronsmore » were produced through the D(d, n){sup 3}He reaction by using a deuterium gas target. A small {sup 238}U fission chamber was adopted for absolute neutron flux determination and a BF{sub 3} long counter was used for neutron flux monitor. Present experimental data are compared with existing evaluations and measurement.« less

  7. Photofission cross-section ratio measurement of 235 U/ 238 U using monoenergetic photons in the energy range of 9.0–16.6 MeV

    DOE PAGES

    Krishichayan,; Bhike, Megha; Finch, S. W.; ...

    2017-05-01

    Photofission cross-section ratios of 235U and 238U have been measured using monoenergetic photon beams from the High Intensity Gamma-ray Source facility at the Triangle Universities Nuclear Laboratory. These measurements have been performed in small energy steps between 9.0 and 16.6 MeV using a dual-fission ionization chamber. The measured cross-section ratios are compared with the previous experimental data as well as with the recent evaluated nuclear data library ENDF.

  8. Defect formation in MeV H+ implanted GaN and 4H-SiC investigated by cross-sectional Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Huang, Kai; Jia, Qi; You, Tiangui; Zhang, Shibin; Lin, Jiajie; Zhang, Runchun; Zhou, Min; Yu, Wenjie; Zhang, Bo; Ou, Xin; Wang, Xi

    2017-09-01

    Cross-sectional Raman spectroscopy is used to characterize the defect formation and the defect recovery in MeV H+ implanted bulk GaN and 4H-SiC in the high energy MeV ion-cut process. The Raman intensity decreases but the forbidden modes are activated at the damage region, and the intensity decrease is proportional to the damage level. The Raman spectrum is quite sensitive to detect the damage recovery after annealing. The main peak intensity increases and the forbidden mode disappears in both annealed GaN and 4H-SiC samples. The Raman spectra of GaN samples annealed at different temperatures suggest that higher annealing temperature is more efficient for damage recovery. While, the Raman spectra of SiC indicate that higher implantation temperature results in heavier lattice damage and other polytype clusters might be generated by high annealing temperature in the annealed SiC samples. The cross-sectional Raman spectroscopy is a straightforward method to characterize lattice damage and damage recovery in high energy ion-cut process. It can serve as a fast supplementary measurement technique to Rutherford backscattering spectrometry (RBS), nuclear reaction analysis (NRA) and transmission electron microscope (TEM) for the defect characterizations.

  9. Neutron Fission of 235,237,239U and 241,243Pu: Cross Sections, Integral Cross Sections and Cross Sections on Excited States

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Younes, W; Britt, H C

    In a recent paper submitted to Phys. Rev. C they have presented estimates for (n,f) cross sections on a series of Thorium, Uranium and Plutonium isotopes over the range E{sub n} = 0.1-2.5 MeV. The (n,f) cross sections for many of these isotopes are difficult or impossible to measure in the laboratory. The cross sections were obtained from previous (t,pf) reaction data invoking a model which takes into account the differences between (t,pf) and (n,f) reaction processes, and which includes improved estimates for the neutron compound formation process. The purpose of this note is: (1) to compare the estimated crossmore » sections to current data files in both ENDF and ENDL databases; (2) to estimate ratios of cross sections relatively to {sup 235}U integrated over the ''tamped flattop'' critical assembly spectrum that was used in the earlier {sup 237}U report; and (3) to show the effect on the integral cross sections when the neutron capturing state is an excited rotational state or an isomer. The isomer and excited state results are shown for {sup 235}U and {sup 237}U.« less

  10. Microscopic description of production cross sections including deexcitation effects

    NASA Astrophysics Data System (ADS)

    Sekizawa, Kazuyuki

    2017-07-01

    Background: At the forefront of the nuclear science, production of new neutron-rich isotopes is continuously pursued at accelerator laboratories all over the world. To explore the currently unknown territories in the nuclear chart far away from the stability, reliable theoretical predictions are inevitable. Purpose: To provide a reliable prediction of production cross sections taking into account secondary deexcitation processes, both particle evaporation and fission, a new method called TDHF+GEMINI is proposed, which combines the microscopic time-dependent Hartree-Fock (TDHF) theory with a sophisticated statistical compound-nucleus deexcitation model, GEMINI++. Methods: Low-energy heavy ion reactions are described based on three-dimensional Skyrme-TDHF calculations. Using the particle-number projection method, production probabilities, total angular momenta, and excitation energies of primary reaction products are extracted from the TDHF wave function after collision. Production cross sections for secondary reaction products are evaluated employing GEMINI++. Results are compared with available experimental data and widely used grazing calculations. Results: The method is applied to describe cross sections for multinucleon transfer processes in 40Ca+124Sn (Ec .m .≃128.54 MeV ), 48Ca+124Sn (Ec .m .≃125.44 MeV ), 40Ca+208Pb (Ec .m .≃208.84 MeV ), 58Ni+208Pb (Ec .m .≃256.79 MeV ), 64Ni+238U (Ec .m .≃307.35 MeV ), and 136Xe+198Pt (Ec .m .≃644.98 MeV ) reactions at energies close to the Coulomb barrier. It is shown that the inclusion of secondary deexcitation processes, which are dominated by neutron evaporation in the present systems, substantially improves agreement with the experimental data. The magnitude of the evaporation effects is very similar to the one observed in grazing calculations. TDHF+GEMINI provides better description of the absolute value of the cross sections for channels involving transfer of more than one proton, compared to the grazing

  11. Investigation of 14-15 MeV ( n, t) Reaction Cross-sections by Using New Evaluated Empirical and Semi-empirical Systematic Formulas

    NASA Astrophysics Data System (ADS)

    Tel, E.; Aydın, A.; Kaplan, A.; Şarer, B.

    2008-09-01

    In the hybrid reactor, tritium self-sufficiency must be maintained for a commercial power plant. For self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. Working out the systematics of ( n, t) reaction cross-sections are of great importance for the definition of the excitation function character for the given reaction taking place on various nuclei at energies up to 20 MeV. In this study we have investigated asymmetry term effect for the ( n, t) reaction cross-sections at 14-15 neutron incident energy. It has been discussed the odd-even effect and the pairing effect considering binding energy systematic of the nuclear shell model for the new experimental data and new cross-sections formulas ( n, t) reactions developed by Tel et al. We have determined a different parameter groups by the classification of nuclei into even-even, even-odd and odd-even for ( n, t) reactions cross-sections. The obtained empirical and semi-empirical formulas by fitting two parameter for ( n, t) reactions were given. All calculated results have been compared with the experimental data and the other semi-empirical formulas.

  12. Cross section asymmetry of two-body carbon disintegration 12C (γ , p)11B with polarized photons at energy 40-50 MeV

    NASA Astrophysics Data System (ADS)

    Burdeinyi, D.; Brudvik, J.; Fissum, K.; Ganenko, V.; Hansen, K.; Isaksson, L.; Livingston, K.; Lundin, M.; Nilsson, B.; Schroder, B.

    2017-01-01

    The cross section asymmetry of 12C (γ ,p01)11B and 12C (γ ,p2-6)11B reactions has been studied at the energy range 40-55 MeV, using linearly polarized tagged photons of the MAX-lab facility. The asymmetry of the 12C (γ ,p01)11B processes, which assume the one-body mechanism of the reaction, is Σ ≈ 0.82 ± 0.05 for photon energies 45-50 MeV. The asymmetry for the 12C (γ ,p2-6)11B reactions, which produce a maximum at excitation energy ∼ 6 MeV, is Σ ≈ 0.53 ± 0.13 for a photon energy 49 MeV. It is close to the asymmetry of reaction of the free deuteron photodisintegration, and can be resulted from the two-body mechanism of the photon absorption.

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

    PubMed

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

    2012-01-27

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

  14. 12C(n , 2 n )11C cross section from threshold to 26.5 MeV

    NASA Astrophysics Data System (ADS)

    Yuly, M.; Eckert, T.; Hartshaw, G.; Padalino, S. J.; Polsin, D. N.; Russ, M.; Simone, A. T.; Brune, C. R.; Massey, T. N.; Parker, C. E.; Fitzgerald, R.; Sangster, T. C.; Regan, S. P.

    2018-02-01

    The 12C(n ,2 n )11C cross section was measured from just below threshold to 26.5 MeV using the Pelletron accelerator at Ohio University. Monoenergetic neutrons, produced via the 3H(d ,n )4He reaction, were allowed to strike targets of polyethylene and graphite. Activation of both targets was measured by counting positron annihilations resulting from the β+ decay of 11C. Annihilation gamma rays were detected, both in coincidence and singly, using back-to-back NaI detectors. The incident neutron flux was determined indirectly via 1H(n ,p ) protons elastically scattered from the polyethylene target. Previous measurements fall into upper and lower bands; the results of the present measurement are consistent with the upper band.

  15. Optical Model and Cross Section Uncertainties

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Herman,M.W.; Pigni, M.T.; Dietrich, F.S.

    2009-10-05

    Distinct minima and maxima in the neutron total cross section uncertainties were observed in model calculations using spherical optical potential. We found this oscillating structure to be a general feature of quantum mechanical wave scattering. Specifically, we analyzed neutron interaction with 56Fe from 1 keV up to 65 MeV, and investigated physical origin of the minima.We discuss their potential importance for practical applications as well as the implications for the uncertainties in total and absorption cross sections.

  16. Activation cross-sections of proton induced reactions on vanadium in the 37-65 MeV energy range

    NASA Astrophysics Data System (ADS)

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

    2016-08-01

    Experimental excitation functions for proton induced reactions on natural vanadium in the 37-65 MeV energy range were measured with the activation method using a stacked foil irradiation technique. By using high resolution gamma spectrometry cross-section data for the production of 51,48Cr, 48V, 48,47,46,44m,44g,43Sc and 43,42K were determined. Comparisons with the earlier published data are presented and results predicted by different theoretical codes (EMPIRE and TALYS) are included. Thick target yields were calculated from a fit to our experimental excitation curves and compared with the earlier experimental yield data. Depth distribution curves to be used for thin layer activation (TLA) are also presented.

  17. Computing the cross sections of nuclear reactions with nuclear clusters emission for proton energies between 30 MeV and 2.6 GeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Korovin, Yu. A.; Maksimushkina, A. V., E-mail: AVMaksimushkina@mephi.ru; Frolova, T. A.

    2016-12-15

    The cross sections of nuclear reactions involving emission of clusters of light nuclei in proton collisions with a heavy-metal target are computed for incident-proton energies between 30 MeV and 2.6 GeV. The calculation relies on the ALICE/ASH and CASCADE/INPE computer codes. The parameters determining the pre-equilibrium cluster emission are varied in the computation.

  18. Semi-empirical and empirical L X-ray production cross sections for elements with 50 ⩽ Z ⩽ 92 for protons of 0.5 3.0 MeV

    NASA Astrophysics Data System (ADS)

    Nekab, M.; Kahoul, A.

    2006-04-01

    We present in this contribution, semi-empirical production cross sections of the main X-ray lines Lα, Lβ and Lγ for elements from Sn to U and for protons with energies varying from 0.5 to 3.0 MeV. The theoretical X-ray production cross sections are firstly calculated from the theoretical ionization cross sections of the L i ( i = 1, 2, 3) subshell within the ECPSSR theory. The semi-empirical Lα, Lβ and Lγ cross sections are then deduced by fitting the available experimental data normalized to their corresponding theoretical values and give the better representation of the experimental data in some cases. On the other hand, the experimental data are directly fitted to deduce the empirical L X-ray production cross sections. A comparison is made between the semi-empirical cross sections, the empirical cross sections reported in this work and the empirical ones reported by Reis and Jesus [M.A. Reis, A.P. Jesus, Atom. Data Nucl. Data Tables 63 (1996) 1] and those of Strivay and Weber [Strivay, G. Weber, Nucl. Instr. and Meth. B 190 (2002) 112].

  19. Cross section measurement of alpha particle induced nuclear reactions on natural cadmium up to 52MeV.

    PubMed

    Ditrói, F; Takács, S; Haba, H; Komori, Y; Aikawa, M

    2016-12-01

    Cross sections of alpha particle induced nuclear reactions have been measured on thin natural cadmium targets foils in the energy range from 11 to 51.2MeV. This work was a part of our systematic study on excitation functions of light ion induced nuclear reactions on different target materials. Regarding the cross sections, the alpha induced reactions are not deeply enough investigated. Some of the produced isotopes are of medical interest, others have application in research and industry. The radioisotope 117m Sn is a very important theranostic (therapeutic + diagnostic) radioisotope, so special care was taken to the results for that isotope. The well-established stacked foil technique followed by gamma-spectrometry with HPGe gamma spectrometers were used. The target and monitor foils in the stack were commercial high purity metal foils. From the irradiated targets 117m Sn, 113 Sn, 110 Sn, 117m,g In, 116m In, 115m In, 114m In, 113m In, 111 In, 110m,g In, 109m In, 108m,g In, 115g Cd and 111m Cd were identified and their excitation functions were derived. The results were compared with the data of the previous measurements from the literature and with the results of the theoretical nuclear reaction model code calculations TALYS 1.8 (TENDL-2015) and EMPIRE 3.2 (Malta). From the cross section curves thick target yields were calculated and compared with the available literature data. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Measurement of 58Fe (p , n)58Co reaction cross-section within the proton energy range of 3.38 to 19.63 MeV

    NASA Astrophysics Data System (ADS)

    Ghosh, Reetuparna; Badwar, Sylvia; Lawriniang, Bioletty; Jyrwa, Betylda; Naik, Haldhara; Naik, Yeshwant; Suryanarayana, Saraswatula Venkata; Ganesan, Srinivasan

    2017-08-01

    The 58Fe (p , n)58Co reaction cross-section within Giant Dipole Resonance (GDR) region i.e. from 3.38 to 19.63 MeV was measured by stacked-foil activation and off-line γ-ray spectrometric technique using the BARC-TIFR Pelletron facility at Mumbai. The present data were compared with the existing literature data and found to be in good agreement. The 58Fe (p , n)58Co reaction cross-section as a function of proton energy was also theoretically calculated by using the computer code TALYS-1.8 and found to be in good agreement, which shows the validity of the TALYS-1.8 program.

  1. Cross sections of proton-induced nuclear reactions on bismuth and lead up to 100 MeV

    NASA Astrophysics Data System (ADS)

    Mokhtari Oranj, L.; Jung, N. S.; Bakhtiari, M.; Lee, A.; Lee, H. S.

    2017-04-01

    Production cross sections of 209Bi(p , x n )207,206,205,204,203Po, 209Bi(p , pxn) 207,206,205,204,203,202Bi, and natPb(p , x n ) 206,205,204,203,202,201Bi reactions were measured to fill the gap in the excitation functions up to 100 MeV as well as to figure out the effects of different nuclear properties on proton-induced reactions including heavy nuclei. The targets were arranged in two different stacks consisting of Bi, Pb, Al, Au foils and Pb plates. The proton beam intensity was determined by the activation analysis method using 27Al(p ,3 p n )24Na, 197Au(p ,p n )196Au, and 197Au(p , p 3 n )194Au monitor reactions in parallel as well as the Gafchromic film dosimetry method. The activities of produced radionuclei in the foils were measured by the HPGe spectroscopy system. Over 40 new cross sections were measured in the investigated energy range. A satisfactory agreement was observed between the present experimental data and the previously published data. Excitation functions of mentioned reactions were calculated by using the theoretical model based on the latest version of the TALYS code and compared to the new data as well as with other data in the literature. Additionally, the effects of various combinations of the nuclear input parameters of different level density models, optical model potentials, and γ-ray strength functions were considered. It was concluded that if certain level density models are used, the calculated cross sections could be comparable to the measured data. Furthermore, the effects of optical model potential and γ-ray strength functions were considerably lower than that of nuclear level densities.

  2. The 12C(n, 2n)11C cross section from threshold to 26.5 MeV

    PubMed Central

    Eckert, T.; Hartshaw, G.; Padalino, S. J.; Polsin, D. N.; Russ, M.; Simone, A. T.; Brune, C. R.; Massey, T. N.; Parker, C. E.; Fitzgerald, R.; Sangster, T. C.; Regan, S. P.

    2018-01-01

    The 12C(n, 2n)11C cross section was measured from just below threshold to 26.5 MeV using the Pelletron accelerator at Ohio University. Monoenergetic neutrons, produced via the 3H(d,n)4He reaction, were allowed to strike targets of polyethylene and graphite. Activation of both targets was measured by counting positron annihilations resulting from the β+ decay of 11C. Annihilation gamma rays were detected, both in coincidence and singly, using back-to-back NaI detectors. The incident neutron flux was determined indirectly via 1H(n,p) protons elastically scattered from the polyethylene target. Previous measurements fall into upper and lower bands; the results of the present measurement are consistent with the upper band. PMID:29732443

  3. The 12C(n, 2n)11C cross section from threshold to 26.5 MeV.

    PubMed

    Yuly, M; Eckert, T; Hartshaw, G; Padalino, S J; Polsin, D N; Russ, M; Simone, A T; Brune, C R; Massey, T N; Parker, C E; Fitzgerald, R; Sangster, T C; Regan, S P

    2018-02-01

    The 12 C(n, 2n) 11 C cross section was measured from just below threshold to 26.5 MeV using the Pelletron accelerator at Ohio University. Monoenergetic neutrons, produced via the 3 H(d,n) 4 He reaction, were allowed to strike targets of polyethylene and graphite. Activation of both targets was measured by counting positron annihilations resulting from the β + decay of 11 C. Annihilation gamma rays were detected, both in coincidence and singly, using back-to-back NaI detectors. The incident neutron flux was determined indirectly via 1 H(n,p) protons elastically scattered from the polyethylene target. Previous measurements fall into upper and lower bands; the results of the present measurement are consistent with the upper band.

  4. Measurement of the neutron-capture cross section of 76Ge and 74Ge below 15 MeV and its relevance to 0 νββ decay searches of 76Ge

    NASA Astrophysics Data System (ADS)

    Bhike, Megha; Fallin, B.; Krishichayan; Tornow, W.

    2015-02-01

    The neutron radiative-capture cross section of 76Ge was measured between 0.4 and 14.8 MeV using the activation technique. Germanium samples with the isotopic abundance of ∼ 86%76Ge and ∼ 14%74Ge used in the 0 νββ searches by the GERDA and Majorana Collaborations were irradiated with monoenergetic neutrons produced at eleven energies via the 3H (p , n)3He, 2H (d , n)3He and 3H (d , n)4He reactions. Previously, data existed only at thermal energies and at 14 MeV. As a by-product, capture cross-section data were also obtained for 74Ge at neutron energies below 8 MeV. Indium and gold foils were irradiated simultaneously for neutron fluence determination. High-resolution γ-ray spectroscopy was used to determine the γ-ray activity of the daughter nuclei of interest. For the 76Ge total capture cross section the present data are in good agreement with the TENDL-2013 model calculations and the ENDF/B-VII.1 evaluations, while for the 74Ge (n , γ)75Ge reaction, the present data are about a factor of two larger than predicted. It was found that the 74Ge (n , γ)75Ge yield in the High-Purity Germanium (HPGe) detectors used by the GERDA and Majorana Collaborations is only about a factor of two smaller than the 76Ge (n , γ)77Ge yield due to the larger cross section of the former reaction.

  5. Production cross sections of deuteron-induced reactions on natural palladium for Ag isotopes

    NASA Astrophysics Data System (ADS)

    Ukon, Naoyuki; Aikawa, Masayuki; Komori, Yukiko; Haba, Hiromitsu

    2018-07-01

    Activation cross sections for deuteron-induced reactions on natural palladium were measured up to 24 MeV using the stacked-foil method and the high resolution gamma-ray spectroscopy. The production cross sections of 103Ag, the parent of a medical radioactive isotope 103Pd, were obtained. We found that our result is in good agreement with the previous data up to 20.3 MeV, and obtained new data at higher energies. In addition, the production cross sections of 104g+mAg, 105Ag, 106mAg, 110mAg and 111Ag were presented.

  6. Measurement of the argon-38(n,2n)argon-37 and calcium- 40(n,alpha)argon-37 cross sections, and National Ignition Facility concrete activation using the rotating target neutron source. The design of an experiment to measure the beryllium-9(n,gamma)beryllium-10 cross section at 14 MeV

    NASA Astrophysics Data System (ADS)

    Belian, Anthony Paul

    The Rotating Target Neutron Source (RTNS) was used in experiments to measure neutron induced cross sections at 14 MeV, and the activation properties of a specific mix of concrete. The RTNS is an accelerator based DT fusion neutron source located at the University of California, Berkeley. Two of the experiments performed for this thesis were specifically of interest for the construction and operation of the National Ignition Facility (NIF), they were the 38Ar(n,2n)37Ar cross section measurement, and the concrete activation measurement. The NIF is a large multi-beam laser facility that will study the effects of age on the nation's stockpile of nuclear weapons. The NIF, when fully operational, will focus the energy of 192 Neodymium glass lasers onto a 1 mm diameter pellet filled with deuterium and tritium fuel. This pellet is compressed by the laser energy giving some of the individual atoms of deuterium and tritium enough kinetic energy to overcome the coulomb barrier and fuse. The energy output from these pellet implosions will be in the range of tens of mega-joules (MJ). The 38Ar(n,2n)37Ar reaction will be useful to NIF scientists to measure important parameters such as target energy yield and areal density. In order to make these measurements precise, an accurate 38Ar(n,2n)37Ar cross section was necessary. The cross sections measured were: 74.9 +/- 3.8 millibarns (mb) at 13.3 +/- 0.01 MeV, 89.2 +/- 4.0 mb at 14.0 +/- 0.03 MeV, and 123.57 +/- 6.4 mb at 15.0 +/- 0.06 MeV. With anticipated energy yields in the tens of mega-joules per pellet implosion, the number of neutrons released is in the range of 1019 to 1020 neutrons per implosion. With such a large number of neutrons, minimizing the activation of the surrounding structure is very much of interest for the sake of personnel radiation safety. To benchmark the computer codes used to calculate the anticipated neutron activation of target bay concrete, samples were irradiated at the RTNS. Dose rates from each sample

  7. Neutron elastic and inelastic cross section measurements for 28Si

    NASA Astrophysics Data System (ADS)

    Derdeyn, E. C.; Lyons, E. M.; Morin, T.; Hicks, S. F.; Vanhoy, J. R.; Peters, E. E.; Ramirez, A. P. D.; McEllistrem, M. T.; Mukhopadhyay, S.; Yates, S. W.

    2017-09-01

    Neutron elastic and inelastic cross sections are critical for design and implementation of nuclear reactors and reactor equipment. Silicon, an element used abundantly in fuel pellets as well as building materials, has little to no experimental cross sections in the fast neutron region to support current theoretical evaluations, and thus would benefit from any contribution. Measurements of neutron elastic and inelastic differential scattering cross sections for 28Si were performed at the University of Kentucky Accelerator Laboratory for incident neutron energies of 6.1 MeV and 7.0 MeV. Neutrons were produced by accelerated deuterons incident on a deuterium gas cell. These nearly mono-energetic neutrons then scattered off a natural Si sample and were detected using liquid deuterated benzene scintillation detectors. Scattered neutron energy was deduced using time-of-flight techniques in tandem with kinematic calculations for an angular distribution. The relative detector efficiency was experimentally determined over a neutron energy range from approximately 0.5 to 7.75 MeV prior to the experiment. Yields were corrected for multiple scattering and neutron attenuation in the sample using the forced-collision Monte Carlo correction code MULCAT. Resulting cross sections will be presented along with comparisons to various data evaluations. Research is supported by USDOE-NNSA-SSAP: NA0002931, NSF: PHY-1606890, and the Donald A. Cowan Physics Institute at the University of Dallas.

  8. Measurement of pion induced neutron-production double-differential cross sections on Fe and Pb at 870 MeV and 2.1 GeV

    NASA Astrophysics Data System (ADS)

    Iwamoto, Y.; Shigyo, N.; Satoh, D.; Kunieda, S.; Watanabe, T.; Ishimoto, S.; Tenzou, H.; Maehata, K.; Ishibashi, K.; Nakamoto, T.; Numajiri, M.; Meigo, S.; Takada, H.

    2004-08-01

    Neutron-production double-differential cross sections for 870 MeV π+ and π- and 2.1 GeV π+ mesons incident on iron and lead targets were measured with NE213 liquid scintillators by time-of-flight technique. NE213 liquid scintillators 12.7 cm in diameter and 12.7 cm thick were placed in directions of 15, 30, 60, 90, 120, and 150° . The typical flight path length was 1.5 m . Neutron detection efficiencies were evaluated by calculation results of SCINFUL and CECIL codes. The experimental results were compared with JAERI quantum molecular dynamics code. For the meson incident reactions, adoption of NN in-medium effects was slightly useful for reproducing 870 MeV π+ -incident neutron yields at neutron energies of 10 30 MeV , as was the case for proton incident reactions. The π- incident reaction generates more neutrons than π+ incidence as the number of nucleons in targets decrease.

  9. Cross Sections Calculations of ( d, t) Nuclear Reactions up to 50 MeV

    NASA Astrophysics Data System (ADS)

    Tel, E.; Yiğit, M.; Tanır, G.

    2013-04-01

    In nuclear fusion reactions two light atomic nuclei fuse together to form a heavier nucleus. Fusion power is the power generated by nuclear fusion processes. In contrast with fission power, the fusion reaction processes does not produce radioactive nuclides. The fusion will not produce CO2 or SO2. So the fusion energy will not contribute to environmental problems such as particulate pollution and excessive CO2 in the atmosphere. Fusion powered electricity generation was initially believed to be readily achievable, as fission power had been. However, the extreme requirements for continuous reactions and plasma containment led to projections being extended by several decades. In 2010, more than 60 years after the first attempts, commercial power production is still believed to be unlikely before 2050. Although there have been significant research and development studies on the inertial and magnetic fusion reactor technology, there is still a long way to go to penetrate commercial fusion reactors to the energy market. In the fusion reactor, tritium self-sufficiency must be maintained for a commercial power plant. Therefore, for self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. Working out the systematics of ( d, t) nuclear reaction cross sections is of great importance for the definition of the excitation function character for the given reaction taking place on various nuclei at different energies. Since the experimental data of charged particle induced reactions are scarce, self-consistent calculation and analyses using nuclear theoretical models are very important. In this study, ( d, t) cross sections for target nuclei 19F, 50Cr, 54Fe, 58Ni, 75As, 89Y, 90Zr, 107Ag, 127I, 197Au and 238U have been investigated up to 50 MeV deuteron energy. The excitation functions for ( d, t) reactions have been calculated by pre-equilibrium reaction mechanism. Calculation results have been also compared with the available measurements in

  10. K and L X-ray production cross sections and intensity ratios of rare-earth elements for proton impact in the energy range 20-25 MeV

    NASA Astrophysics Data System (ADS)

    Hajivaliei, M.; Puri, Sanjiv; Garg, M. L.; Mehta, D.; Kumar, A.; Chamoli, S. K.; Avasthi, D. K.; Mandal, A.; Nandi, T. K.; Singh, K. P.; Singh, Nirmal; Govil, I. M.

    2000-02-01

    The Kα1, Kα2, Kβ1, Kβ2, and the Lℓ, Lα, Lβ and Lγ X-ray production (XRP) cross sections and the relative intensity ratios for seven rare-earth elements with 60⩽Z⩽70 have been measured for 20, 22 and 25 MeV proton impact. The experimental data on the L-shell XRP cross sections for high energy proton impact have been reported for the first time. The measured XRP cross sections for all the K-lines and the relative intensity ratios Kα1/Kα, Kα2/Kα, Kβ1/Kα, Kβ2/Kα and Kβ/Kα are in good agreement with the theoretical ones calculated using ECPSSR ionisation cross sections for all the elements investigated at the three beam energies. The Lℓ, Lα, Lβ, and Lγ XRP cross sections measured at the three proton energies are found to be in general higher than the theoretical values calculated using the ECPSSR ionisation cross sections and the RDHS model-based Li sub-shell fluorescence and Coster-Kronig (CK) yields. The measured relative intensity ratios Lβ/Lα, and Lγ/Lα exhibit good agreement with the theoretical ones for all the elements under investigation, whereas the Lℓ/Lα ratios are found to deviate from the theoretical ones.

  11. Proton-Proton Scattering at 105 Mev and 75 Mev

    DOE R&D Accomplishments Database

    Birge, R. W.; Kruse, U. E.; Ramsey, N. F.

    1951-01-31

    The scattering of protons by protons provides an important method for studying the nature of nuclear forces. Recent proton-proton scattering experiments at energies as high as thirty Mev{sup 1} have failed to show any appreciable contribution to the cross section from higher angular momentum states, but it is necessary to bring in tensor forces to explain the magnitude of the observed cross section.

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

    NASA Astrophysics Data System (ADS)

    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.

  13. Cross section of the 197Au(n,2n)196Au reaction

    NASA Astrophysics Data System (ADS)

    Kalamara, A.; Vlastou, R.; Kokkoris, M.; Diakaki, M.; Serris, M.; Patronis, N.; Axiotis, M.; Lagoyannis, A.

    2017-09-01

    The 197Au(n,2n)196Au reaction cross section has been measured at two energies, namely at 17.1 MeV and 20.9 MeV, by means of the activation technique, relative to the 27Al(n,α)24Na reference reaction cross section. Quasi-monoenergetic neutron beams were produced at the 5.5 MV Tandem T11/25 accelerator laboratory of NCSR "Demokritos", by means of the 3H(d,n)4He reaction, implementing a new Ti-tritiated target of ˜ 400 GBq activity. The induced γ-ray activity at the targets and reference foils has been measured with HPGe detectors. The cross section for the population of the second isomeric (12-) state m2 of 196Au was independently determined. Auxiliary Monte Carlo simulations were performed using the MCNP code. The present results are in agreement with previous experimental data and with theoretical calculations of the measured reaction cross sections, which were carried out with the use of the EMPIRE code.

  14. Experimental results on antiproton-nuclei annihilation cross section at very low energies

    NASA Astrophysics Data System (ADS)

    Aghai-Khozani, H.; Barna, D.; Corradini, M.; Hayano, R.; Hori, M.; Kobayashi, T.; Leali, M.; Lodi-Rizzini, E.; Mascagna, V.; Prest, M.; Soter, A.; Todoroki, K.; Vallazza, E.; Venturelli, L.; Zurlo, N.

    2014-03-01

    Investigating the antiproton cross section on nuclei at low energies (1 eV - 1 MeV) is of great interest for fundamental cosmology and nuclear physics as well. The process is of great relevance for the models which try to explain the matter/antimatter asymmetry in the universe assuming the existence of the so-called "island" where antinucleon-nucleon annihilations occur in the border region [1]. For the nuclear physics point of view, the annihilation process is considered a useful tool to evaluate the neutron/proton ratio probing the external region of the nucleus. Moreover, the cross section measured at LEAR in the 80s-90s showed an unexpected behaviour for energies below 1 MeV. The results showed a saturation with the atomic mass number against the A2/3 trend which is known for higher energies. The ASACUSA collaboration at CERN measured 5.3 MeV antiproton annihilation cross section on different nuclei whose results demonstrated to be consistent with the black-disk model with the Coulomb correction [2]. So far, experimental limits prevented the data acquisition for energies below 1 MeV. In 2012 the 100 keV region has been investigated for the first time [3]. We present here the results of the experiment.

  15. Calculation of the Effective Cross Sections of the Reaction X(n,p)Y with Neutrons in the Energy Range 2-5 Mev; CALCULO DE SECCIONES EFICACES X(n,p)Y CON NEUTRONES DE ENERGIAS ENTRE 2-5 Mev

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rapaport, J.; Trier, A.

    1960-05-01

    Parallel with experimental work to measure the ic neutrons between 2 and 3.6 Mev, it was necessary to estimate the theoretical behavior of these cross sections. The statistical theory of Blatt and Weisskopf was used in the calculation. The theoretical results obtained for squarewell and diffuse-well development are compared with the experimental results. (J.S.R.)

  16. Towards the high-accuracy determination of the 238U fission cross section at the threshold region at CERN - n_TOF

    NASA Astrophysics Data System (ADS)

    Diakaki, M.; Audouin, L.; Berthoumieux, E.; Calviani, M.; Colonna, N.; Dupont, E.; Duran, I.; Gunsing, F.; Leal-Cidoncha, E.; Le Naour, C.; Leong, L. S.; Mastromarco, M.; Paradela, C.; Tarrio, D.; Tassan-Got, L.; Aerts, G.; Altstadt, S.; Alvarez, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Badurek, G.; Barbagallo, M.; Baumann, P.; Becares, V.; Becvar, F.; Belloni, F.; Berthier, B.; Billowes, J.; Boccone, V.; Bosnar, D.; Brugger, M.; Calvino, F.; Cano-Ott, D.; Capote, R.; Carrapiço, C.; Cennini, P.; Cerutti, F.; Chiaveri, E.; Chin, M.; Cortes, G.; Cortes-Giraldo, M. A.; Cosentino, L.; Couture, A.; Cox, J.; David, S.; Dillmann, I.; Domingo-Pardo, C.; Dressler, R.; Dridi, W.; Eleftheriadis, C.; Embid-Segura, M.; Ferrant, L.; Ferrari, A.; Finocchiaro, P.; Fraval, K.; Fujii, K.; Furman, W.; Ganesan, S.; Garcia, A. R.; Giubrone, G.; Gomez-Hornillos, M. B.; Goncalves, I. F.; Gonzalez-Romero, E.; Goverdovski, A.; Gramegna, F.; Griesmayer, E.; Guerrero, C.; Gurusamy, P.; Haight, R.; Heil, M.; Heinitz, S.; Igashira, M.; Isaev, S.; Jenkins, D. G.; Jericha, E.; Kadi, Y.; Kaeppeler, F.; Karadimos, D.; Karamanis, D.; Kerveno, M.; Ketlerov, V.; Kivel, N.; Kokkoris, M.; Konovalov, V.; Krticka, M.; Kroll, J.; Lampoudis, C.; Langer, C.; Lederer, C.; Leeb, H.; Lo Meo, S.; Losito, R.; Lozano, M.; Manousos, A.; Marganiec, J.; Martinez, T.; Marrone, S.; Massimi, C.; Mastinu, P.; Mendoza, E.; Mengoni, A.; Milazzo, P. M.; Mingrone, F.; Mirea, M.; Mondelaers, W.; Moreau, C.; Mosconi, M.; Musumarra, A.; O'Brien, S.; Pancin, J.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perkowski, J.; Perrot, L.; Pigni, M. T.; Plag, R.; Plompen, A.; Plukis, L.; Poch, A.; Pretel, C.; Praena, J.; Quesada, J.; Rauscher, T.; Reifarth, R.; Riego, A.; Roman, F.; Rudolf, G.; Rubbia, C.; Rullhusen, P.; Salgado, J.; Santos, C.; Sarchiapone, L.; Sarmento, R.; Saxena, A.; Schillebeeckx, P.; Schmidt, S.; Schumann, D.; Stephan, C.; Tagliente, G.; Tain, J. L.; Tavora, L.; Terlizzi, R.; Tsinganis, A.; Valenta, S.; Vannini, G.; Variale, V.; Vaz, P.; Ventura, A.; Versaci, R.; Vermeulen, M. J.; Villamarin, D.; Vincente, M. C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Wallner, A.; Walter, S.; Ware, T.; Weigand, M.; Weiß, C.; Wiesher, M.; Wisshak, K.; Wright, T.; Zugec, P.

    2016-03-01

    The 238U fission cross section is an international standard beyond 2 MeV where the fission plateau starts. However, due to its importance in fission reactors, this cross-section should be very accurately known also in the threshold region below 2 MeV. The 238U fission cross section has been measured relative to the 235U fission cross section at CERN - n_TOF with different detection systems. These datasets have been collected and suitably combined to increase the counting statistics in the threshold region from about 300 keV up to 3 MeV. The results are compared with other experimental data, evaluated libraries, and the IAEA standards.

  17. Cross sections of the {sup 67}Zn(n,{alpha}){sup 64}Ni reaction at 4.0, 5.0, and 6.0 MeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang Guohui; Liu Jiaming; Wu Hao

    2010-11-15

    Experimental cross section data of the {sup 67}Zn(n,{alpha}){sup 64}Ni reaction are very scanty because the residual nucleus {sup 64}Ni is stable and the commonly used activation method is not feasible. As a result, very large deviations (about 10 times) exist among different nuclear data libraries. In the present work, cross sections of the partial {sup 67}Zn(n,{alpha}{sub 0}){sup 64}Ni and total {sup 67}Zn(n,{alpha}){sup 64}Ni reactions are measured at neutron energies of 4.0 and 5.0 MeV for the first time, and those of 6.0 MeV are remeasured for consistency checking. A twin-gridded ionization chamber was used as the charged-particle detector and twomore » enriched back-to-back-set {sup 67}Zn samples were adopted. Experiments were performed at the 4.5 MV Van de Graaff Accelerator of Peking University. Neutrons were produced through the {sup 2}H(d,n){sup 3}He reaction using a deuterium gas target. Absolute neutron flux was determined by counting the fission fragments from a {sup 238}U sample placed inside the gridded ionization chamber while a BF{sub 3} long counter was employed as neutron flux monitor. Present data are compared with results of previous measurements, evaluations, and talys code calculations.« less

  18. Measurements of the differential cross sections for recoil tritons in 4He- 3T scattering at energies between 0.5 and 2.5 MeV

    NASA Astrophysics Data System (ADS)

    Sawicki, J. A.

    1988-03-01

    Differential cross-sections for recoil detection of tritons from elastic scattering of α-particles on tritium were measured at forward recoil angles from 10° and 40° and over incident 4He energies ranging from 0.5 to 2.5 MeV. Thin solid state targets consisted of about 10 16T {at.}/{cm 2} either absorbed in a thin film of titanium or implanted at low energy in the matrix of amorphous silicon. The recoil yields were normalized against the yields of the T(d, α)n reaction measured on the same targets. It is found that the cross sections obtained are considerably enhanced as compared to the Rutherford recoil cross section, what can be attributed to the combined effect of Coulomb and nuclear potentials and formation of compound 7Li nuclei. The applications of the elastic recoil detection as a means for depth profiling of tritium in materials are briefly considered. The measured dependence of the triton recoil cross section on the incident energy of 4He + ions allows profiling the concentration of tritium across a range ˜ l μm below the surface of solids.

  19. New Parameterization of Neutron Absorption Cross Sections

    NASA Technical Reports Server (NTRS)

    Tripathi, Ram K.; Wilson, John W.; Cucinotta, Francis A.

    1997-01-01

    Recent parameterization of absorption cross sections for any system of charged ion collisions, including proton-nucleus collisions, is extended for neutron-nucleus collisions valid from approx. 1 MeV to a few GeV, thus providing a comprehensive picture of absorption cross sections for any system of collision pairs (charged or uncharged). The parameters are associated with the physics of the problem. At lower energies, optical potential at the surface is important, and the Pauli operator plays an increasingly important role at intermediate energies. The agreement between the calculated and experimental data is better than earlier published results.

  20. Low-energy and very-low energy total cross sections for electron collisions with N2

    NASA Astrophysics Data System (ADS)

    Kitajima, Masashi; Kishino, Takaya; Okumura, Takuma; Kobayashi, Naomasa; Sayama, Atsushi; Mori, Yuma; Hosaka, Kouichi; Odagiri, Takeshi; Hoshino, Masamitsu; Tanaka, Hiroshi

    2017-06-01

    Absolute grand total cross sections for electron scattering from N2 are obtained in the energy range from 20 eV down to 5 meV with very narrow electron energy width of 9 meV using the threshold-photoelectron source. Total cross sections obtained in the present study are compared with the previous experimentally obtained results. At the very-low energy region below 50 meV, the present total cross sections are somewhat smaller than those reported by the Aarhus group [S.V. Hoffmann et al., Rev. Sci. Instrum. 73, 4157 (2002)], which has been the only experimental work that provided the total cross sections in the very-low energy region. The energy positions of the peaks in the total cross sections due to the 2Πg shape resonance are obtained with higher accuracy, due to the improved uncertainty of the energy position in the present measurement compared to the previous works. The resonance structure in the total cross sections due to the Feshbach resonances of N2 at around 11.5 eV are also observed. Analysis of the resonant structure was carried out in order to determine the values of resonance width of Feshbach resonances of N2. Contribution to the Topical Issue: "Atomic and Molecular Data and their Applications", edited by Gordon W.F. Drake, Jung-Sik Yoon, Daiji Kato, Grzegorz Karwasz.

  1. SU-E-I-43: Photoelectric Cross Section Revisited

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Haga, A; Nakagawa, K; Kotoku, J

    2015-06-15

    Purpose: The importance of the precision in photoelectric cross-section value increases for recent developed technology such as dual energy computed tomography, in which some reconstruction algorithms require the energy dependence of the photo-absorption in each material composition of human being. In this study, we revisited the photoelectric cross-section calculation by self-consistent relativistic Hartree-Fock (HF) atomic model and compared with that widely distributed as “XCOM database” in National Institute of Standards and Technology, which was evaluated with localdensity approximation for electron-exchange (Fock)z potential. Methods: The photoelectric cross section can be calculated with the electron wave functions in initial atomic state (boundmore » electron) and final continuum state (photoelectron). These electron states were constructed based on the selfconsistent HF calculation, where the repulsive Coulomb potential from the electron charge distribution (Hartree term) and the electron exchange potential with full electromagnetic interaction (Fock term) were included for the electron-electron interaction. The photoelectric cross sections were evaluated for He (Z=2), Be (Z=4), C (Z=6), O (Z=8), and Ne (Z=10) in energy range of 10keV to 1MeV. The Result was compared with XCOM database. Results: The difference of the photoelectric cross section between the present calculation and XCOM database was 8% at a maximum (in 10keV for Be). The agreement tends to be better as the atomic number increases. The contribution from each atomic shell has a considerable discrepancy with XCOM database except for K-shell. However, because the photoelectric cross section arising from K-shell is dominant, the net photoelectric cross section was almost insensitive to the different handling in Fock potential. Conclusion: The photoelectric cross-section program has been developed based on the fully self-consistent relativistic HF atomic model. Due to small effect on the

  2. Lanl Neutron-Induced Fission Cross Section Measurement Program

    NASA Astrophysics Data System (ADS)

    Laptev, A. B.; Tovesson, F.; Hill, T. S.

    2014-09-01

    A well established program of neutron-induced fission cross section measurement at Los Alamos Neutron Science Center (LANSCE) is supporting the Fuel Cycle Research program (FC R&D). Combining measurements at two LANSCE facilities, the Lujan Center and the Weapons Neutron Research facility (WNR), cover neutron energies over 10 orders of magnitude: from sub-thermal up to 200 MeV. A parallel-plate fission ionization chamber was used as a fission fragment detector. The 235U(n,f) standard was used as the reference. Fission cross sections have been measured for multiple actinides. The new data presented here completes the suite of long-lived Uranium isotopes that were investigated with this experimental approach. The cross section data are presented in comparison with existing evaluations and previous measurements.

  3. Neutron scattering cross section measurements for Fe 56

    DOE PAGES

    Ramirez, A. P. D.; Vanhoy, J. R.; Hicks, S. F.; ...

    2017-06-09

    Elastic and inelastic differential cross sections for neutron scattering from 56Fe have been measured for several incident energies from 1.30 to 7.96 MeV at the University of Kentucky Accelerator Laboratory. Scattered neutrons were detected using a C 6D 6 liquid scintillation detector using pulse-shape discrimination and time-of-flight techniques. The deduced cross sections have been compared with previously reported data, predictions from evaluation databases ENDF, JENDL, and JEFF, and theoretical calculations performed using different optical model potentials using the TALYS and EMPIRE nuclear reaction codes. The coupled-channel calculations based on the vibrational and soft-rotor models are found to describe the experimentalmore » (n,n 0) and (n,n 1) cross sections well.« less

  4. Neutron scattering cross section measurements for 56Fe

    NASA Astrophysics Data System (ADS)

    Ramirez, A. P. D.; Vanhoy, J. R.; Hicks, S. F.; McEllistrem, M. T.; Peters, E. E.; Mukhopadhyay, S.; Harrison, T. D.; Howard, T. J.; Jackson, D. T.; Lenzen, P. D.; Nguyen, T. D.; Pecha, R. L.; Rice, B. G.; Thompson, B. K.; Yates, S. W.

    2017-06-01

    Elastic and inelastic differential cross sections for neutron scattering from 56Fe have been measured for several incident energies from 1.30 to 7.96 MeV at the University of Kentucky Accelerator Laboratory. Scattered neutrons were detected using a C6D6 liquid scintillation detector using pulse-shape discrimination and time-of-flight techniques. The deduced cross sections have been compared with previously reported data, predictions from evaluation databases ENDF, JENDL, and JEFF, and theoretical calculations performed using different optical model potentials using the talys and empire nuclear reaction codes. The coupled-channel calculations based on the vibrational and soft-rotor models are found to describe the experimental (n ,n0 ) and (n ,n1 ) cross sections well.

  5. Absolute single-photoionization cross sections of Se 2 + : Experiment and theory

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Macaluso, D. A.; Aguilar, A.; Kilcoyne, A. L. D.

    2015-12-28

    Absolute single-photoionization cross-section measurements for Se 2+ ions were performed at the Advanced Light Source at Lawrence Berkeley National Laboratory using the merged-beams photo-ion technique. Measurements were made at a photon energy resolution of 24 ± 3 meV in the photon energy range 23.5-42.5 eV, spanning the ground state and low-lying metastable state ionization thresholds. Here, to clearly resolve the resonant structure near the ground-state threshold, high-resolution measurements were made from 30.0 to 31.9 eV at a photon energy resolution of 6.7 ± 0.7 meV. Numerous resonance features observed in the experimental spectra are assigned and their energies and quantummore » defects tabulated. The high-resolution cross-section measurements are compared with large-scale, state-of-the-art theoretical cross-section calculations obtained from the Dirac Coulomb R -matrix method. Suitable agreement is obtained over the entire photon energy range investigated. In conclusion, these results are an experimental determination of the absolute photoionization cross section of doubly ionized selenium and include a detailed analysis of the photoionization resonance spectrum of this ion.« less

  6. Measurement of the neutron-capture cross section of ⁷⁶Ge and ⁷⁴Ge below 15 MeV and its relevance to 0νββ decay searches of ⁷⁶Ge

    DOE PAGES

    Bhike, Megha; Fallin, B.; Krishichayan, none; ...

    2015-02-01

    The neutron radiative-capture cross section of ⁷⁶Ge was measured between 0.4 and 14.8 MeV using the activation technique. Germanium samples with the isotopic abundance of ~86% ⁷⁶Ge and ~14% ⁷⁴Ge used in the 0νββ searches by the GERDA and Majorana Collaborations were irradiated with monoenergetic neutrons produced at eleven energies via the ³H(p,n)³He, ²H(d,n)³He and ³H(d,n)⁴He reactions. Previously, data existed only at thermal energies and at 14 MeV. As a by-product, capture cross-section data were also obtained for ⁷⁴Ge at neutron energies below 8 MeV. Indium and gold foils were irradiated simultaneously for neutron fluence determination. High-resolution γ-ray spectroscopy wasmore » used to determine the γ-ray activity of the daughter nuclei of interest. For the ⁷⁶Ge total capture cross section the present data are in good agreement with the TENDL-2013 model calculations and the ENDF/B-VII.1 evaluations, while for the ⁷⁴Ge(n,γ)⁷⁵Ge reaction, the present data are about a factor of two larger than predicted. It was found that the ⁷⁴Ge(n,γ)⁷⁵Ge yield in the High-Purity Germanium (HPGe) detectors used by the GERDA and Majorana Collaborations is only about a factor of two smaller than the ⁷⁶Ge(n,γ)⁷⁷Ge yield due to the larger cross section of the former reaction.« less

  7. Measurement of the neutron-capture cross section of ⁷⁶Ge and ⁷⁴Ge below 15 MeV and its relevance to 0νββ decay searches of ⁷⁶Ge

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bhike, Megha; Fallin, B.; Krishichayan, none

    The neutron radiative-capture cross section of ⁷⁶Ge was measured between 0.4 and 14.8 MeV using the activation technique. Germanium samples with the isotopic abundance of ~86% ⁷⁶Ge and ~14% ⁷⁴Ge used in the 0νββ searches by the GERDA and Majorana Collaborations were irradiated with monoenergetic neutrons produced at eleven energies via the ³H(p,n)³He, ²H(d,n)³He and ³H(d,n)⁴He reactions. Previously, data existed only at thermal energies and at 14 MeV. As a by-product, capture cross-section data were also obtained for ⁷⁴Ge at neutron energies below 8 MeV. Indium and gold foils were irradiated simultaneously for neutron fluence determination. High-resolution γ-ray spectroscopy wasmore » used to determine the γ-ray activity of the daughter nuclei of interest. For the ⁷⁶Ge total capture cross section the present data are in good agreement with the TENDL-2013 model calculations and the ENDF/B-VII.1 evaluations, while for the ⁷⁴Ge(n,γ)⁷⁵Ge reaction, the present data are about a factor of two larger than predicted. It was found that the ⁷⁴Ge(n,γ)⁷⁵Ge yield in the High-Purity Germanium (HPGe) detectors used by the GERDA and Majorana Collaborations is only about a factor of two smaller than the ⁷⁶Ge(n,γ)⁷⁷Ge yield due to the larger cross section of the former reaction.« less

  8. Determination of the cross section for (n,p) and (n,α) reactions on (165)Ho at 13.5 and 14.8MeV.

    PubMed

    Luo, Junhua; An, Li; Jiang, Li; He, Long

    2015-04-01

    Activation cross-sections for the (165)Ho(n,p)(165)Dy and (165)Ho(n,α)(162)Tb reactions were measured by means of the activation method at 13.5 and 14.8MeV, to resolve inconsistencies in existing data. A neutron beam produced via the (3)H(d,n)(4)He reaction was used. Statistical model calculations were performed using the nuclear-reaction codes EMPIRE-3.2 Malta and TALYS-1.6 with default parameters, at neutron energies varying from the reaction threshold to 20MeV. Results are also discussed and compared with some corresponding values found in the literature. The calculational results on the (165)Ho(n,α)(162)Tb reaction agreed fairly well with experimental data, but there were large discrepancies in the results for the (165)Ho(n,p)(165)Dy reaction. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Photoabsorption cross section of acetylene in the EUV region

    NASA Technical Reports Server (NTRS)

    Wu, C. Y. R.; Judge, D. L.

    1985-01-01

    The measurement of the absolute photoabsorption cross sections of C2H2 in the 175-740 A region by means of a double ionization chamber is reported. The continuum background source is the synchrotron radiation emitted by the Wisconsin 240 MeV electron storage ring. It is found that the cross sections range from 2 to a maximum of 36 Mb. Two new Rydberg series are identified and the cross section data are applied in the analysis of various sum rules. From the rules, it is shown that the data of C2H2 in the 580-1088 A range may be too low, while the measured ionization transition moment may be too high.

  10. Measurement of the Ir-191,193(n,2n)Ir-190,192 Reaction Cross Section Between 9.0 and 16.5 MeV

    NASA Astrophysics Data System (ADS)

    Wildenhain, Elizabeth; Finch, Sean; Tornow, Werner; Krishichayan, F.

    2017-09-01

    Iridium is one of the elements prioritized by Nonproliferation and Homeland Security agencies. In addition, Ir-192 is being used in various medical treatments. Improved data and corresponding evaluations of neutron-induced reactions on the iridium isotopes are required to meet the demands of several applications of societal interest. This study measured the cross section of the Ir-191,193(n, 2n)Ir-190,192 reactions at energies from 9.0 to 16.5 MeV using the activation technique. Natural Ir samples [Ir-191 37.3%, Ir-193 62.7%] were sandwiched between Au-197 monitor foils and irradiated with monoenergetic neutron beams at the tandem facility of the Triangle Universities Nuclear Laboratory (TUNL). Gamma rays from the irradiated samples were counted in TUNL's low background facility using high-efficient HPGe detectors. Measured cross-section data are compared to previous data and to predictions from nuclear data libraries (e.g. ENDF). Research at TUNL funded by the NSF.

  11. Neutron-capture cross-section measurements of 74Ge and 76Ge in the energy region 0.4-14.8 MeV for neutrinoless double β decay applications

    NASA Astrophysics Data System (ADS)

    Bhike, Megha; Tornow, Werner

    2013-10-01

    Fast neutron capture cross sections for the reactions 74Ge(n, γ)75Ge and 76Ge(n, γ)77Ge have been measured in the neutron energy region 0.4-14.8 MeV with the activation method. The results are important to identify backgrounds in the neutrinoless double- β decay experiments GERDA and MAJORANA, which use germanium as both source and detector. Isotopically enriched targets which consisted of 86% of 76Ge and 14% of 74Ge were irradiated with mono-energetic neutrons produced via 3H(p,n)3He, 2H(d,n)3He and 3H(d,n)4He reactions. The cross sections were determined relative to 197Au(n, γ)198Au, 115In(n,n')115mIn and 197Au(n,2n)196Au standard cross sections. The activities of the products were measured using high-resolution γ-ray spctroscopy. The present results are compared with the evaluated data from ENDF/B-VII.1 and TALYS.

  12. Target correlation effects on neutron-nucleus total, absorption, and abrasion cross sections

    NASA Technical Reports Server (NTRS)

    Cucinotta, Francis A.; Townsend, Lawrence W.; Wilson, John W.

    1991-01-01

    Second order optical model solutions to the elastic scattering amplitude were used to evaluate total, absorption, and abrasion cross sections for neutron nucleus scattering. Improved agreement with experimental data for total and absorption cross sections is found when compared with first order (coherent approximation) solutions, especially below several hundred MeV. At higher energies, the first and second order solutions are similar. There are also large differences in abrasion cross section calculations; these differences indicate a crucial role for cluster knockout in the abrasion step.

  13. Elastic and inelastic neutron scattering cross sections for fission reactor applications

    NASA Astrophysics Data System (ADS)

    Hicks, S. F.; Chakraborty, A.; Combs, B.; Crider, B. P.; Downes, L.; Girgis, J.; Kersting, L. J.; Kumar, A.; Lueck, C. J.; McDonough, P. J.; McEllistrem, M. T.; Peters, E. E.; Prados-Estevz, F. M.; Schniederjan, J.; Sidwell, L.; Sigillito, A. J.; Vanhoy, J. R.; Watts, D.; Yates, S. W.

    2013-04-01

    Nuclear data important for the design and development of the next generation of light-water reactors and future fast reactors include neutron elastic and inelastic scattering cross sections on important structural materials, such as Fe, and on coolant materials, such as Na. These reaction probabilities are needed since neutron reactions impact fuel performance during irradiations and the overall efficiency of reactors. While neutron scattering cross sections from these materials are available for certain incident neutron energies, the fast neutron region, particularly above 2 MeV, has large gaps for which no measurements exist, or the existing uncertainties are large. Measurements have been made at the University of Kentucky Accelerator Laboratory to measure neutron scattering cross sections on both Fe and Na in the region where these gaps occur and to reduce the uncertainties on scattering from the ground state and first excited state of these nuclei. Results from measurements on Fe at incident neutron energies between 2 and 4 MeV will be presented and comparisons will be made to model calculations available from data evaluators.

  14. Cross Sections of P-Induced Reactions up to 100 MeV for the Interpretation of Solar Cosmic Ray Produced Nuclides

    NASA Astrophysics Data System (ADS)

    Schiekel, T.; Rosel, R.; Herpers, U.; Bodemann, R.; Michel, R.; Dittrich, B.; Hofmann, H. J.; Suter, M.; Wolfli, W.; Holmqvist, B.; Conde, H.; Malmborg, P.

    1992-07-01

    Integral excitation functions for the production of residual nuclides by proton-induced reactions are the basic data for an accurate modelling of the interactions of solar cosmic ray (SCR) particles with extraterrestrial matter. Due to the relatively low energies (<200 MeV/A) of SCR particles the production of nuclear active secondary particles can be widely neglected and theoretical production rate depth profiles can be calculated by simply folding the depth dependent SCR spectra with thin target cross sections of the underlying nuclear reactions. The accuracy of such calculations exclusively depends on the quality of the available cross sections. For many nuclides, in particular for long-lived radionuclides and stable rare gas isotopes, the exis- ting cross section database is neither comprehensive nor reliable. Therefore, we started a series of experiments to improve this situation. Eighteen elements (C, N as Si3N4, O as SiO2, Mg, Al, Si, Ti, V, Mn as Mn/Ni-alloy, Fe, Co, Ni, Cu, Zr, Nb, Rh, Ba as Ba-contai- ning glass, and Au) were irradiated with 94 and 99 MeV protons at the external beam of the TSL-cyclotron at Uppsala. Cross sections were determined using the stacked foil technique. Beam monitoring was done by investigating the production of ^22Na from Al, for which evaluated cross sections exist. Residual nuclides were measured by X-, gamma- and accelerator-mass spectrometry. In order to check the quality of our experimental procedure some target elements (22 <= Z <= 28) were included in the new exper- iments, which had been formerly irradiated at Julich, at Louvain La Neuve, and at IPN Orsay. Comparisons between the earlier measurements (1,2) and the new cross sections showed excellent agreement. Up to now, cross sections were measured for more than 120 different reactions. Here, we report on the results obtained for the target elements C, N, O, Mg, Al, and Si. The status of experimental excitation functions for the production of some radionuclides

  15. Double differential cross section calculations for 16O and 90Zr elements

    NASA Astrophysics Data System (ADS)

    Demirkol, İ.

    2018-04-01

    Double differential cross sections in proton induced reactions on 90Zr and O2 (inert matrix fuel) is calculated at the bombarding energies between 29 and 300 MeV. The proton-induced nuclear reaction cross section data can be used in technical applications such as the isotope production alternatives, spallation reactions for production of neutrons in spallation neutron source, etc. In this study, the cascade excition model including the effect of preequilibrium is used to calculate the differential cross section. Then, the obtained results are discussed and compared with available experimental data.

  16. s-wave threshold in electron attachment - Observations and cross sections in CCl4 and SF6 at ultralow electron energies

    NASA Technical Reports Server (NTRS)

    Chutjian, A.; Alajajian, S. H.

    1985-01-01

    The threshold photoionization method was used to study low-energy electron attachment phenomena in and cross sections of CCl4 and SF6 compounds, which have applications in the design of gaseous dielectrics and diffuse discharge opening switches. Measurements were made at electron energies from below threshold to 140 meV at resolutions of 6 and 8 meV. A narrow resolution-limited structure was observed in electron attachment to CCl4 and SF6 at electron energies below 10 meV, which is attributed to the divergence of the attachment cross section in the limit epsilon, l approaches zero. The results are compared with experimental collisional-ionization results, electron-swarm unfolded cross sections, and earlier threshold photoionization data.

  17. Partial Cross Sections of Neutron-Induced Reactions on nCu at En = 6, 8, 10, 12, 14, and 16 MeV for 0νββ Background Studies

    NASA Astrophysics Data System (ADS)

    Gooden, M. E.; Fallin, B. A.; Finch, S. W.; Kelley, J. H.; Howell, C. R.; Rusev, G.; Tonchev, A. P.; Tornow, W.; Stanislav, V.

    2014-05-01

    Partial cross-section measurements of (n,n'γ) reactions on natCu were carried out at TUNL using monoenergetic neutrons at six energies of En = 6, 8, 10, 12, 14, 16 MeV. These studies were performed to provide accurate cross-section data on materials abundant in experimental setups involving HPGe detectors used to search for rare events, like the neutrino-less double-beta decay of 76Ge. Spallation and (α,n) neutrons are expected to cause the largest source of external background in the energy region of interest. At TUNL pulsed neutron beams were produced via the 2H(d,n)3He reaction and the deexcitation γ rays from the reaction natCu(n,xγ) were detected with clover HPGe detectors. Cross-section results for the strongest transtions in 63Cu and 65Cu will be reported, and will compared to model calculations and to data recently obtained at LANL with a white neutron beam.

  18. Experimental measurements with Monte Carlo corrections and theoretical calculations of neutron inelastic scattering cross section of 115In

    NASA Astrophysics Data System (ADS)

    Wang, Chao; Xiao, Jun; Luo, Xiaobing

    2016-10-01

    The neutron inelastic scattering cross section of 115In has been measured by the activation technique at neutron energies of 2.95, 3.94, and 5.24 MeV with the neutron capture cross sections of 197Au as an internal standard. The effects of multiple scattering and flux attenuation were corrected using the Monte Carlo code GEANT4. Based on the experimental values, the 115In neutron inelastic scattering cross sections data were theoretically calculated between the 1 and 15 MeV with the TALYS software code, the theoretical results of this study are in reasonable agreement with the available experimental results.

  19. Large Scale Accelerator Production of 225Ac: Effective Cross sections for 78-192 MeV Protons Incident on 232Th Targets

    DOE PAGES

    Griswold, Justin R; Medvedev, Dmitri G.; Engle, Jonathan W.; ...

    2016-09-28

    Actinium-225 and 213Bi have been used successfully in targeted alpha therapy (TAT) in preclinical and clinical research. This paper is a continuation of research activities aiming to expand the availability of 225Ac. The high energy proton spallation reaction on natural thorium metal target has been utilized to produce millicurie quantities of 225Ac. The results of sixteen irradiation experiments of Th metal at beam energies between 78 and 200 MeV are summarized in this work. Irradiations have been conducted at Brookhaven National Laboratory (BNL) and Los Alamos National Laboratory (LANL), while target dissolution and processing was carried out at Oak Ridgemore » National Laboratory (ORNL). Excitation functions for actinium and thorium isotopes as well as for some of the fission products are presented. The cross sections for production of 225Ac range from 3.6 to 16.7 mb in the incident proton energy range of 78 to 192 MeV. Based on these data, production of Curie quantities of 225Ac is possible by irradiating a 5.0 g cm -2232Th target for 10 days in either BNL or LANL proton irradiation facilities.« less

  20. Large scale accelerator production of 225Ac: Effective cross sections for 78-192MeV protons incident on 232Th targets.

    PubMed

    Griswold, J R; Medvedev, D G; Engle, J W; Copping, R; Fitzsimmons, J M; Radchenko, V; Cooley, J C; Fassbender, M E; Denton, D L; Murphy, K E; Owens, A C; Birnbaum, E R; John, K D; Nortier, F M; Stracener, D W; Heilbronn, L H; Mausner, L F; Mirzadeh, S

    2016-12-01

    Actinium-225 and 213 Bi have been used successfully in targeted alpha therapy (TAT) in preclinical and clinical research. This paper is a continuation of research activities aiming to expand the availability of 225 Ac. The high-energy proton spallation reaction on natural thorium metal targets has been utilized to produce millicurie quantities of 225 Ac. The results of sixteen irradiation experiments of thorium metal at beam energies between 78 and 192MeV are summarized in this work. Irradiations have been conducted at Brookhaven National Laboratory (BNL) and Los Alamos National Laboratory (LANL), while target dissolution and processing was carried out at Oak Ridge National Laboratory (ORNL). Excitation functions for actinium and thorium isotopes, as well as for some of the fission products, are presented. The cross sections for production of 225 Ac range from 3.6 to 16.7mb in the incident proton energy range of 78-192MeV. Based on these data, production of curie quantities of 225 Ac is possible by irradiating a 5.0gcm -2 232 Th target for 10 days in either BNL or LANL proton irradiation facilities. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Extension of activation cross-section data of deuteron induced nuclear reactions on cadmium up to 50 MeV

    NASA Astrophysics Data System (ADS)

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

    2016-10-01

    The excitation functions for 109,110g,111m+g,113m,114m,115mIn, 107,109,115m,115gCd and 105g,106m,110g,111Ag are presented for stacked foil irradiations on natCd targets in the 49-33 MeV deuteron energy domain. Reduced uncertainty is obtained by determining incident particle flux and energy scale relative to re-measured monitor reactions natAl(d,x)22,24Na. The results were compared to our earlier studies on natCd and on enriched 112Cd targets. The merit of the values predicted by the TALYS 1.6 code (resulting from a weighted combination of reaction cross-section data on all stable Cd isotopes as available in the on-line libraries TENDL-2014 and TENDL-2015) is discussed. Influence on optimal production routes for several radionuclides with practical applications (111In, 114mIn, 115Cd, 109,107Cd….) is reviewed.

  2. Measurement of (n,α) cross section for set of structural material isotopes

    NASA Astrophysics Data System (ADS)

    Khryachkov, Vitaly; Gurbich, Alexander; Khromyleva, Tatiana; Bondarenko, Ivan; Ketlerov, Vladimir; Prusachenko, Pavel

    2017-09-01

    A novel spectrometer was developed and used to measure the cross section for the (n,α) reaction at IPPE. Direct measurements of the α-particles yield from solid isotopic pure targets of 50, 52 and 53 chromium, 54 and 57 iron, 60 nickel, and 64 zinc were carried out in the neutron energy range from 4.7 to 7.2 MeV. For some isotopes the (n,α) reaction cross-section for neutron energies less than 14 MeV were measured for the first time. The result of the comparison of new experimental data with the evaluated data from libraries ENDF/B VII, JENDL 4.0, JEFF 3.1, ROSFOND 2010 and BROND 3 and with the experimental data of other authors is presented.

  3. Fragmentation cross sections and binding energies of neutron-rich nuclei

    NASA Astrophysics Data System (ADS)

    Tsang, M. B.; Lynch, W. G.; Friedman, W. A.; Mocko, M.; Sun, Z. Y.; Aoi, N.; Cook, J. M.; Delaunay, F.; Famiano, M. A.; Hui, H.; Imai, N.; Iwasaki, H.; Motobayashi, T.; Niikura, M.; Onishi, T.; Rogers, A. M.; Sakurai, H.; Suzuki, H.; Takeshita, E.; Takeuchi, S.; Wallace, M. S.

    2007-10-01

    An exponential dependence of the fragmentation cross section on the average binding energy is observed and reproduced with a statistical model. The observed functional dependence is robust and allows the extraction of binding energies from measured cross sections. From the systematics of Cu isotope cross sections, the binding energies of Cu76,77,78,79 have been extracted. They are 636.94±0.4,647.1±0.4,651.6±0.4, and 657.8±0.5 MeV, respectively. Specifically, the uncertainty of the binding energy of Cu75 is reduced from 980 keV, as listed in the 2003 mass table of Audi, Wapstra, and Thibault to 400 keV. The predicted cross sections of two near drip-line nuclei, Na39 and Mg40 from the fragmentation of Ca48 are discussed.

  4. Measurement of the normalized U 238 ( n , f ) / U 235 ( n , f ) cross section ratio from threshold to 30 MeV with the NIFFTE fission Time Projection Chamber

    DOE PAGES

    Casperson, R. J.; Asner, D. M.; Baker, J.; ...

    2018-03-23

    We present that the normalized 238U(n,f)/ 235U(n,f) cross section ratio has been measured using the NIFFTE fission Time Projection Chamber (fissionTPC) from the reaction threshold to 30 MeV . The fissionTPC is a two-volume MICROMEGAS time projection chamber that allows for full three-dimensional reconstruction of fission-fragment ionization profiles from neutron-induced fission. The measurement was performed at the Los Alamos Neutron Science Center, where the neutron energy is determined from neutron time of-flight. The 238U(n,f)/ 235U(n,f) ratio reported here is the first cross section measurement made with the fissionTPC, and will provide new experimental data for evaluation of the 238U(n,f) crossmore » section, an important standard used in neutron-flux measurements. Use of a development target in this work prevented the determination of an absolute normalization, to be addressed in future measurements. Instead, the measured cross section ratio has been normalized to ENDF/B-VIII.β5 at 14.5 MeV.« less

  5. Measurement of the normalized U 238 ( n , f ) / U 235 ( n , f ) cross section ratio from threshold to 30 MeV with the NIFFTE fission Time Projection Chamber

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Casperson, R. J.; Asner, D. M.; Baker, J.

    We present that the normalized 238U(n,f)/ 235U(n,f) cross section ratio has been measured using the NIFFTE fission Time Projection Chamber (fissionTPC) from the reaction threshold to 30 MeV . The fissionTPC is a two-volume MICROMEGAS time projection chamber that allows for full three-dimensional reconstruction of fission-fragment ionization profiles from neutron-induced fission. The measurement was performed at the Los Alamos Neutron Science Center, where the neutron energy is determined from neutron time of-flight. The 238U(n,f)/ 235U(n,f) ratio reported here is the first cross section measurement made with the fissionTPC, and will provide new experimental data for evaluation of the 238U(n,f) crossmore » section, an important standard used in neutron-flux measurements. Use of a development target in this work prevented the determination of an absolute normalization, to be addressed in future measurements. Instead, the measured cross section ratio has been normalized to ENDF/B-VIII.β5 at 14.5 MeV.« less

  6. Measurement of the antiproton-nucleus annihilation cross-section at low energy

    NASA Astrophysics Data System (ADS)

    Aghai-Khozani, H.; Bianconi, A.; Corradini, M.; Hayano, R.; Hori, M.; Leali, M.; Lodi Rizzini, E.; Mascagna, V.; Murakami, Y.; Prest, M.; Vallazza, E.; Venturelli, L.; Yamada, H.

    2018-02-01

    Systematic measurements of the annihilation cross sections of low energy antinucleons were performed at CERN in the 80's and 90's. However the antiproton data on medium-heavy and heavy nuclear targets are scarce. The ASACUSA Collaboration at CERN has measured the antiproton annihilation cross section on carbon at 5.3 MeV: the value is (1.73 ± 0.25) barn. The result is compared with the antineutron experimental data and with the theoretical previsions.

  7. Total reaction cross sections in CEM and MCNP6 at intermediate energies

    DOE PAGES

    Kerby, Leslie M.; Mashnik, Stepan G.

    2015-05-14

    Accurate total reaction cross section models are important to achieving reliable predictions from spallation and transport codes. The latest version of the Cascade Exciton Model (CEM) as incorporated in the code CEM03.03, and the Monte Carlo N-Particle transport code (MCNP6), both developed at Los Alamos National Laboratory (LANL), each use such cross sections. Having accurate total reaction cross section models in the intermediate energy region (50 MeV to 5 GeV) is very important for different applications, including analysis of space environments, use in medical physics, and accelerator design, to name just a few. The current inverse cross sections used inmore » the preequilibrium and evaporation stages of CEM are based on the Dostrovsky et al. model, published in 1959. Better cross section models are now available. Implementing better cross section models in CEM and MCNP6 should yield improved predictions for particle spectra and total production cross sections, among other results.« less

  8. Total reaction cross sections in CEM and MCNP6 at intermediate energies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kerby, Leslie M.; Mashnik, Stepan G.

    Accurate total reaction cross section models are important to achieving reliable predictions from spallation and transport codes. The latest version of the Cascade Exciton Model (CEM) as incorporated in the code CEM03.03, and the Monte Carlo N-Particle transport code (MCNP6), both developed at Los Alamos National Laboratory (LANL), each use such cross sections. Having accurate total reaction cross section models in the intermediate energy region (50 MeV to 5 GeV) is very important for different applications, including analysis of space environments, use in medical physics, and accelerator design, to name just a few. The current inverse cross sections used inmore » the preequilibrium and evaporation stages of CEM are based on the Dostrovsky et al. model, published in 1959. Better cross section models are now available. Implementing better cross section models in CEM and MCNP6 should yield improved predictions for particle spectra and total production cross sections, among other results.« less

  9. Vacuum ultraviolet photoionization cross section of the hydroxyl radical.

    PubMed

    Dodson, Leah G; Savee, John D; Gozem, Samer; Shen, Linhan; Krylov, Anna I; Taatjes, Craig A; Osborn, David L; Okumura, Mitchio

    2018-05-14

    The absolute photoionization spectrum of the hydroxyl (OH) radical from 12.513 to 14.213 eV was measured by multiplexed photoionization mass spectrometry with time-resolved radical kinetics. Tunable vacuum ultraviolet (VUV) synchrotron radiation was generated at the Advanced Light Source. OH radicals were generated from the reaction of O( 1 D) + H 2 O in a flow reactor in He at 8 Torr. The initial O( 1 D) concentration, where the atom was formed by pulsed laser photolysis of ozone, was determined from the measured depletion of a known concentration of ozone. Concentrations of OH and O( 3 P) were obtained by fitting observed time traces with a kinetics model constructed with literature rate coefficients. The absolute cross section of OH was determined to be σ(13.436 eV) = 3.2 ± 1.0 Mb and σ(14.193 eV) = 4.7 ± 1.6 Mb relative to the known cross section for O( 3 P) at 14.193 eV. The absolute photoionization spectrum was obtained by recording a spectrum at a resolution of 8 meV (50 meV steps) and scaling to the single-energy cross sections. We computed the absolute VUV photoionization spectrum of OH and O( 3 P) using equation-of-motion coupled-cluster Dyson orbitals and a Coulomb photoelectron wave function and found good agreement with the observed absolute photoionization spectra.

  10. Vacuum ultraviolet photoionization cross section of the hydroxyl radical

    NASA Astrophysics Data System (ADS)

    Dodson, Leah G.; Savee, John D.; Gozem, Samer; Shen, Linhan; Krylov, Anna I.; Taatjes, Craig A.; Osborn, David L.; Okumura, Mitchio

    2018-05-01

    The absolute photoionization spectrum of the hydroxyl (OH) radical from 12.513 to 14.213 eV was measured by multiplexed photoionization mass spectrometry with time-resolved radical kinetics. Tunable vacuum ultraviolet (VUV) synchrotron radiation was generated at the Advanced Light Source. OH radicals were generated from the reaction of O(1D) + H2O in a flow reactor in He at 8 Torr. The initial O(1D) concentration, where the atom was formed by pulsed laser photolysis of ozone, was determined from the measured depletion of a known concentration of ozone. Concentrations of OH and O(3P) were obtained by fitting observed time traces with a kinetics model constructed with literature rate coefficients. The absolute cross section of OH was determined to be σ(13.436 eV) = 3.2 ± 1.0 Mb and σ(14.193 eV) = 4.7 ± 1.6 Mb relative to the known cross section for O(3P) at 14.193 eV. The absolute photoionization spectrum was obtained by recording a spectrum at a resolution of 8 meV (50 meV steps) and scaling to the single-energy cross sections. We computed the absolute VUV photoionization spectrum of OH and O(3P) using equation-of-motion coupled-cluster Dyson orbitals and a Coulomb photoelectron wave function and found good agreement with the observed absolute photoionization spectra.

  11. Determination of the fast-neutron-induced fission cross-section of 242Pu at nELBE

    NASA Astrophysics Data System (ADS)

    Kögler, Toni; Beyer, Roland; Junghans, Arnd R.; Schwengner, Ronald; Wagner, Andreas

    2018-03-01

    The fast-neutron-induced fission cross section of 242Pu was determined in the energy range of 0.5 MeV to 10MeV at the neutron time-of-flight facility nELBE. Using a parallel-plate fission ionization chamber this quantity was measured relative to 235U(n,f). The number of target nuclei was thereby calculated by means of measuring the spontaneous fission rate of 242Pu. An MCNP 6 neutron transport simulation was used to correct the relative cross section for neutron scattering. The determined results are in good agreement with current experimental and evaluated data sets.

  12. Direct processes in 54-MeV Li-7 breakup reactions on C-12 and Au-197 targets, and the extraction of astrophysical cross sections

    NASA Astrophysics Data System (ADS)

    Gazes, S. B.; Mason, J. E.; Roberts, R. B.; Teichmann, S. G.

    1992-01-01

    Strong direct processes were observed for elastic breakup in 54-MeV Li-7 + C-12, Au-197 reactions. In the case of C-12, the observed Li-7 to alpha + t direct-breakup yield was significantly larger than predicted by a Coulomb-breakup calculation, indicating the importance of the nuclear field. For Au-197, final-state interactions produced a strong distortion in the fragment energy spectra, as well as a modulation of the coincidence efficiency for different detector geometries. Such Coulomb effects are found to severely complicate the extraction of radiative-capture cross sections from direct-breakup data.

  13. Fragmentation cross sections and binding energies of neutron-rich nuclei

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsang, M. B.; Lynch, W. G.; Mocko, M.

    An exponential dependence of the fragmentation cross section on the average binding energy is observed and reproduced with a statistical model. The observed functional dependence is robust and allows the extraction of binding energies from measured cross sections. From the systematics of Cu isotope cross sections, the binding energies of {sup 76,77,78,79}Cu have been extracted. They are 636.94{+-}0.4,647.1{+-}0.4,651.6{+-}0.4, and 657.8{+-}0.5 MeV, respectively. Specifically, the uncertainty of the binding energy of {sup 75}Cu is reduced from 980 keV, as listed in the 2003 mass table of Audi, Wapstra, and Thibault to 400 keV. The predicted cross sections of two near drip-linemore » nuclei, {sup 39}Na and {sup 40}Mg from the fragmentation of {sup 48}Ca are discussed.« less

  14. Measurements of production cross sections of 10Be and 26Al by 120 GeV and 392 MeV proton bombardment of 89Y, 159Tb, and natCu targets

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sekimoto, S.; Okumura, S.; Yashima, H.

    2015-08-12

    The production cross sections of 10Be and 26Al were measured by accelerator mass spectrometry using 89Y, 159Tb, and natCu targets bombarded by protons with energies E p of 120 GeV and 392 MeV. The production cross sections obtained for 10Be and 26Al were compared with those previously reported using E p = 50 MeV–24 GeV and various targets. It was found that the production cross sections of 10Be monotonically increased with increasing target mass number when the proton energy was greater than a few GeV. On the other hand, it was also found that the production cross sections of 10Bemore » decreased as the target mass number increased from that of carbon to those near the mass numbers of nickel and zinc when the proton energy was below approximately 1 GeV. They also increased as the target mass number increased from near those of nickel and zinc to that of bismuth, in the same proton energy range. Similar results were observed in the production cross sections of 26Al, though the absolute values were quite different between 10Be and 26Al. As a result, the difference between these production cross sections may depend on the impact parameter (nuclear radius) and/or the target nucleus stiffness.« less

  15. Commentary: exciting new developments in fast neutron cross sections and dosimetry

    NASA Astrophysics Data System (ADS)

    Bielajew, A. F.; Chadwick, M. B.

    1998-12-01

    The field of fast neutron therapy, and to some extent the practice of radiation protection in the vicinity of medical linear accelerators, requires accurate physical data. The paucity of physical data for neutron cross sections above about 15 MeV in low- Z materials is best exemplified (and somewhat exaggerated!) in the late Herb Attix's standard textbook Introduction to Radiological Physics and Radiation Dosimetry (Attix 1986). On page 464, the contributions to kerma in tissue from neutrons stops abruptly shortly above about 15 MeV. Photon and electron dosimetry has benefited from a well established and highly cohesive relationship between measurement and theory due to the enormous success of quantum electrodynamics. In contrast, measurements in the field of neutron radiotherapy have benefited less from theory because of the complexity of the quantum mechanics of nuclear structure, especially for light elements. This is because the nuclear levels are widely spaced at low excitation energies unlike for heavy elements where the energy level spacing is more dense and statistical assumptions can be applied with success. This means that accurate measurements are crucial for guiding and testing theoretical development. Measurements contributing to the field of fast neutron dosimetry are few and far between. Amazingly, in this issue of Physics in Medicine and Biology there are two such contributions! The paper by Benck, Slypen, Meulders and Corcalciuc (1998) entitled `Experimental double differential cross sections and derived kerma factors for oxygen at incident neutron energies from reaction thresholds to 65 MeV' reports on a set of measurements of the doubly-differential cross sections (energy and angle) for fast neutrons on for 9 energies between 25 and 65 MeV. The reaction channels measured were (n, px), (n, dx), (n, tx) and (n, x). These cross sections were then integrated to produce partial and total kerma factors. There are several features of this paper that are

  16. Measurements of Deuteron-Induced Activation Cross Sections for IFMIF Accelerator Structural Materials

    NASA Astrophysics Data System (ADS)

    Nakao, Makoto; Hori, Jun-ichi; Ochiai, Kentaro; Sato, Satoshi; Yamauchi, Michinori; Ishioka, Noriko S.; Nishitani, Takeo

    2005-05-01

    Activation cross sections for deuteron-induced reactions on aluminum, copper, and tungsten were measured by using a stacked-foil method. The stacked foils were irradiated with deuteron beam at the AVF cyclotron in the TIARA facility, JAERI. We obtained the activation cross sections for 27Al(d,2p)27Mg, 27Al(d,x)24Na, natCu(d,x)62,63Zn, 61,64Cu, and natW(d,x)181-184,186Re, 187W in the 22-40 MeV region. These cross sections were compared with other experimental ones and the data in the ACSELAM library calculated by the ALICE-F code.

  17. The Study of ( n, d) Reaction Cross Sections for New Evaluated Semi-Empirical Formula Using Optical Model

    NASA Astrophysics Data System (ADS)

    Bölükdemir, M. H.; Tel, E.; Okuducu, Ş.; Aydın, A.

    2009-12-01

    Nuclear fusion can be one of the most attractive sources of energy from the viewpoint of safety and minimal environmental impact. The neutron scattering cross sections data have a critical importance on fusion reactor (and in the fusion-fission hybrid) reactors. So, the study of the systematic of ( n, d) etc., reaction cross sections is of great importance in the definition of the excitation function character for reaction taking place on various nuclei at energies up to 20 MeV. In this study, non-elastic cross-sections have been calculated by using optical model for ( n, d) reactions at 14-15 MeV energy. The excitation function character and reaction Q-values depending on the asymmetry term effect for the ( n, d) reaction have been investigated. New coefficients have been obtained and the semi-empirical formulas including optical model non-elastic effects by fitting two parameters for the ( n, d) reaction cross-sections have been suggested. The obtained cross-section formulas with new coefficients have been compared with the available experimental data and discussed.

  18. Calculated differential and double differential cross section of DT neutron induced reactions on natural chromium (Cr)

    NASA Astrophysics Data System (ADS)

    Rajput, Mayank; Vala, Sudhirsinh; Srinivasan, R.; Abhangi, M.; Subhash, P. V.; Pandey, B.; Rao, C. V. S.; Bora, D.

    2018-01-01

    Chromium is an important alloying element of stainless steel (SS) and SS is the main constituent of structural material proposed for fusion reactors. Energy and double differential cross section data will be required to estimate nuclear responses in the materials used in fusion reactors. There are no experimental data of energy and double differential cross section, available for neutron induced reactions on natural chromium at 14 MeV neutron energy. In this study, energy and double differential cross section data of (n,p) and (n,α) reactions for all the stable isotopes of chromium have been estimated, using appropriate nuclear models in TALYS code. The cross section data of stable isotopes are later converted into the energy and double differential cross section data of natural Cr using the isotopic abundance. The contribution from compound, pre-equilibrium and direct nuclear reaction to total reaction have also been calculated for 52,50Cr(n,p) and 52Cr(n,α). The calculation of energy differential cross section shows that most of emitted protons and alpha particles are of 3 and 8 MeV respectively. The calculated data is compared with the data from EXFOR data library and is found to be in good agreement.

  19. Quasicontinuum γ decay of Zr 91 , 92 : Benchmarking indirect ( n , γ ) cross section measurements for the s process

    DOE PAGES

    Guttormsen, M.; Goriely, S.; Larsen, A. C.; ...

    2017-08-21

    Here, nuclear level densities (NLDs) and γ-ray strength functions (γSFs) have been extracted from particle-γ coincidences of the 92Zr(p,p´γ) 92Zr and 92Zr (p,dγ) 91Zr reactions using the Oslo method. The new 91,92Zr γSF data, combined with photonuclear cross sections, cover the whole energy range from Eγ ≈ 1.5 MeV up to the giant dipole resonance at Eγ ≈ 17 MeV. The wide-range γSF data display structures at Eγ ≈ 9.5 MeV, compatible with a superposition of the spin-flip M1 resonance and a pygmy E1 resonance. Furthermore, the γSF shows a minimum at Eγ ≈ 2–3 MeV and an increase atmore » lower γ-ray energies. The experimentally constrained NLDs and γSFs are shown to reproduce known (n,γ) and Maxwellian-averaged cross sections for 91,92Zr using the TALYS reaction code, thus serving as a benchmark for this indirect method of estimating (n,γ) cross sections for Zr isotopes.« less

  20. Measurement of Activation Cross Sections Producing Short-Lived Nuclei with Pulsed Neutron Beam

    NASA Astrophysics Data System (ADS)

    Shimizu, Toshiaki; Arakita, Kazumasa; Miyazaki, Itaru; Shibata, Michihiro; Kawade, Kiyoshi; Hori, Jun-ichi; Ochiai, Kentaro; Nishitani, Takeo

    2005-05-01

    Activation cross sections for the (n, n') reaction were measured by means of the activation method at the neutron energies of 3.1 and 2.54 MeV by using a pulsed neutron beam. Target nuclei were 79Br, 90Zr, 197Au, and 207Pb, whose half-lives were between 0.8 and 8 s. The cross section for the 90Zr (n, n') 90mZr reaction was obtained for the first time in this energy range. The d-D neutrons were generated by bombarding a deuterated titanium target with a 350-keV d+ beam at the 80-degree beam line of the Fusion Neutronics Source at the Japan Atomic Energy Research Institute. In order to obtain reliable activation cross sections, careful attention was paid to correct the efficiency for a volume source, and the self-absorption of gamma rays in an irradiated sample. The systematics of the (n, n') reaction at the neutron energy of 3.1 MeV, which could be predicted within an accuracy of 50%, was proposed on the basis of our data.

  1. Gadolinium-148 and other spallation production cross section measurements for accelerator target facilities

    NASA Astrophysics Data System (ADS)

    Kelley, Karen Corzine

    At the Los Alamos Neutron Science Center accelerator complex, protons are accelerated to 800 MeV and directed to two tungsten targets, Target 4 at the Weapons Neutron Research facility and the 1L target at the Lujan Center. The Department of Energy requires hazard classification analyses to be performed on these targets and places limits on certain radionuclide inventories in the targets to avoid characterizing the facilities as "nuclear facilities." Gadolinium-148 is a radionuclide created from the spallation of tungsten. Allowed isotopic inventories are particularly low for this isotope because it is an alpha-particle emitter with a 75-year half-life. The activity level of Gadolinium-148 is low, but it encompasses almost two-thirds of the total dose burden for the two tungsten targets based on present yield estimates. From a hazard classification standpoint, this severely limits the lifetime of these tungsten targets. The cross section is not well-established experimentally and this is the motivation for measuring the Gadolinium-148 production cross section from tungsten. In a series of experiments at the Weapons Neutron Research facility, Gadolinium-148 production was measured for 600- and 800-MeV protons on tungsten, tantalum, and gold. These experiments used 3 mum thin tungsten, tantalum, and gold foils and 10 mum thin aluminum activation foils. In addition, spallation yields were determined for many short-lived and long-lived spallation products with these foils using gamma and alpha spectroscopy and compared with predictions of the Los Alamos National Laboratory codes CEM2k+GEM2 and MCNPX. The cumulative Gadolinium-148 production cross section measured from tantalum, tungsten, and gold for incident 600-MeV protons were 15.2 +/- 4.0, 8.31 +/- 0.92, and 0.591 +/- 0.155, respectively. The average production cross sections measured at 800 MeV were 28.6 +/- 3.5, 19.4 +/- 1.8, and 3.69 +/- 0.50 for tantalum, tungsten, and gold, respectively. These cumulative

  2. Measurements of 67Ga production cross section induced by protons on natZn in the low energy range from 1.678 to 2.444 MeV

    NASA Astrophysics Data System (ADS)

    Wachter, J. A.; Miranda, P. A.; Morales, J. R.; Cancino, S. A.; Correa, R.

    2015-02-01

    The experimental production cross section for the reaction natZn(p,x)67Ga has been measured in the energy range from 1.678 to 2.444 MeV. The methodology used in this work is based on characteristic X-ray emitted after irradiation by the daughter nuclei that decays by electron capture (EC) and the use of a complementary PIXE experiment. By doing so, expressions needed to determine cross section values are simplified since experimental factors such as geometric setup and an detector efficiency are avoided. 67Ga is a radionuclide particularly suited for this method since it decays by electron capture in 100% and the subsequent characteristic X-ray emission is easily detected. Natural zinc targets were fabricated by PVD technique and afterwards their thicknesses were determined by Rutherford Backscattering Spectrometry. Cross sections measurements were carried out by using the Van de Graaff accelerator located at Faculty of Sciences, University of Chile. It was found that our data for the natZn(p,x)67Ga reaction are, in general, in good agreement when compared to existing experimental data and to those calculated ALICE/ASH nuclear code. On the other hand, values predicted by Talys-1.6 are showing systematically lower magnitudes than our measured data.

  3. High resolution measurements of the {sup 241}Am(n,2n) reaction cross section

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sage, C.; European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440 Geel; Commissariat a L'Energie Atomique Cadarache, DEN/CAD/DER/SPRC/LEPh, F-13108 St Paul-lez-Durance

    Measurements of the {sup 241}Am(n,2n) reaction cross section have been performed at the Joint Research Centre (JRC) Geel in the frame of a collaboration between the European Commission (EC) JRC and French laboratories from CNRS and the Commissariat a L'Energie Atomique (CEA) Cadarache. Raw material coming from the Atalante facility of CEA Marcoule has been transformed by JRC Karlsruhe into suitable {sup 241}AmO{sub 2} samples embedded in Al{sub 2}O{sub 3} matrices specifically designed for these measurements. The irradiations were carried out at the 7-MV Van de Graaff accelerator. The {sup 241}Am(n,2n) reaction cross section was determined relative to the {supmore » 27}Al(n,alpha){sup 24}Na standard cross section. The measurements were performed in four sessions, using quasi-mono-energetic neutrons with energies ranging from 8 to 21 MeV produced via the {sup 2}H(d,n){sup 3}He and the {sup 3}H(d,n){sup 4}He reactions. The induced activity was measured by standard gamma-ray spectrometry using a high-purity germanium detector. Below 15 MeV, the present results are in agreement with data obtained earlier. Above 15 MeV, these measurements allowed the experimental investigation of the {sup 241}Am(n,2n) reaction cross section for the first time. The present data are in good agreement with predictions obtained with the talys code that uses an optical and fission model developed at CEA.« less

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

    NASA Astrophysics Data System (ADS)

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

    2017-08-01

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

  5. Neutron induced fission cross section measurements of 240Pu and 242Pu

    NASA Astrophysics Data System (ADS)

    Belloni, F.; Eykens, R.; Heyse, J.; Matei, C.; Moens, A.; Nolte, R.; Plompen, A. J. M.; Richter, S.; Sibbens, G.; Vanleeuw, D.; Wynants, R.

    2017-09-01

    Accurate neutron induced fission cross section of 240Pu and 242Pu are required in view of making nuclear technology safer and more efficient to meet the upcoming needs for the future generation of nuclear power plants (GEN-IV). The probability for a neutron to induce such reactions figures in the NEA Nuclear Data High Priority Request List [1]. A measurement campaign to determine neutron induced fission cross sections of 240Pu and 242Pu at 2.51 MeV and 14.83 MeV has been carried out at the 3.7 MV Van De Graaff linear accelerator at Physikalisch-Technische Bundesanstalt (PTB) in Braunschweig. Two identical Frisch Grid fission chambers, housing back to back a 238U and a APu target (A = 240 or A = 242), were employed to detect the total fission yield. The targets were molecular plated on 0.25 mm aluminium foils kept at ground potential and the employed gas was P10. The neutron fluence was measured with the proton recoil telescope (T1), which is the German primary standard for neutron fluence measurements. The two measurements were related using a De Pangher long counter and the charge as monitors. The experimental results have an average uncertainty of 3-4% at 2.51 MeV and for 6-8% at 14.81 MeV and have been compared to the data available in literature.

  6. Poster - 18: New features in EGSnrc for photon cross sections

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ali, Elsayed; Mainegra-Hing, Ernesto; Rogers, Davi

    2016-08-15

    Purpose: To implement two new features in the EGSnrc Monte Carlo system. The first is an option to account for photonuclear attenuation, which can contribute a few percent to the total cross section at the higher end of the energy range of interest to medical physics. The second is an option to use exact NIST XCOM photon cross sections. Methods: For the first feature, the photonuclear total cross sections are generated from the IAEA evaluated data. In the current, first-order implementation, after a photonuclear event, there is no energy deposition or secondary particle generation. The implementation is validated against deterministicmore » calculations and experimental measurements of transmission signals. For the second feature, before this work, if the user explicitly requested XCOM photon cross sections, EGSnrc still used its own internal incoherent scattering cross sections. These differ by up to 2% from XCOM data between 30 keV and 40 MeV. After this work, exact XCOM incoherent scattering cross sections are an available option. Minor interpolation artifacts in pair and triplet XCOM cross sections are also addressed. The default for photon cross section in EGSnrc is XCOM except for the new incoherent scattering cross sections, which have to be explicitly requested. The photonuclear, incoherent, pair and triplet data from this work are available for elements and compounds for photon energies from 1 keV to 100 GeV. Results: Both features are implemented and validated in EGSnrc.Conclusions: The two features are part of the standard EGSnrc distribution as of version 4.2.3.2.« less

  7. Measurements of Radiative Capture Cross Sections at Big Bang Energies

    NASA Astrophysics Data System (ADS)

    Tanaka, Masaomi; Fukuda, Mitsunori; Tanaka, Yutaro; Du, Hang; Ohnishi, Kousuke; Yagi, Shoichi; Sugihara, Takanobu; Hori, Taichi; Nakamura, Shoken; Yanagihara, Rikuto; Matsuta, Kensaku; Mihara, Mototsugu; Nishimura, Daiki; Iwakiri, Shuichi; Kambayashi, Shohei; Kunimatsu, Shota; Sakakibara, Hikaru; Yamaoka, Shintaro

    We measured d(p, γ )3He cross sections at ECM = 0.12, 0.19, 0.44, and 0.57 MeV. In this energy region, available experimental values are systematically smaller than the recent calculation, so that additional experiments are desired for understanding the Big Bang Nucleosynthesis. The experiment was performed by bombarding proton beams to the D2 gas target with the 5 MV Van de Graaff accelerator at Osaka University. The experimental d(p, γ )3He cross sections of the present study are systematically larger than previous data. On the other hand, recent theoretical results by Marcucci et al. are in good agreement with present experimental results.

  8. Extension of activation cross section data of long lived products in deuteron induced nuclear reactions on platinum up to 50 MeV

    NASA Astrophysics Data System (ADS)

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

    2017-06-01

    In the frame of a systematical study of light ion induced nuclear reactions on platinum, activation cross sections for deuteron induced reactions were investigated. Excitation functions were measured in the 20.8-49.2 MeV energy range for the natPt(d,xn)191,192,193,194,195,196m2,196g,198g,199Au, natPt(d,x)188,189,191,195m,197m,197gPt and natPt(d,x)189,190,192,194m2Ir reactions by using the stacked foil irradiation technique. The experimental results are compared with previous results from the literature and with the theoretical predictions in the TENDL-2014 and TENDL-2015 libraries. The applicability of the produced radio-tracers for wear measurements has been presented.

  9. Accurate 238U(n , 2 n )237U reaction cross-section measurements from 6.5 to 14.8 MeV

    NASA Astrophysics Data System (ADS)

    Krishichayan, Bhike, M.; Tornow, W.; Tonchev, A. P.; Kawano, T.

    2017-10-01

    The cross section for the 238U(n ,2 n )237U reaction has been measured in the incident neutron energy range from 6.5 to 14.8 MeV in small energy steps using an activation technique. Monoenergetic neutron beams were produced via the 2H(d ,n )3He and 3H(d ,n )4He reactions. 238U targets were activated along with Au and Al monitor foils to determine the incident neutron flux. The activity of the reaction products was measured in TUNL's low-background counting facility using high-resolution γ -ray spectroscopy. The results are compared with previous measurements and latest data evaluations. Statistical-model calculations, based on the Hauser-Feshbach formalism, have been carried out using the CoH3 code and are compared with the experimental results. The present self-consistent and high-quality data are important for stockpile stewardship and nuclear forensic purposes as well as for the design and operation of fast reactors.

  10. LETTER TO THE EDITOR: Cross sections of 6Li(t,d1)7Li*[0.478] and 6Li(t,p1)8Li*[0.981] nuclear reactions in the 0-2 MeV energy range

    NASA Astrophysics Data System (ADS)

    Voronchev, V. T.; Kukulin, V. I.

    2000-12-01

    An original extrapolation technique developed previously is modified and applied to study nuclear reactions in the 6Li + T system at energies E = 0-2 MeV. Cross sections of gamma-ray-producing reactions 6Li(t,d1)7Li*[0.478] and 6Li(t,p1)8Li*[0.981] with important diagnostic implications are calculated. The (t,d1) nuclear data found exceed those accepted elsewhere by 2.5-3.5 times at sub-barrier energies. The cross sections of the (t,p1) reaction are calculated for the first time.

  11. Activation cross sections of alpha-induced reactions on natIn for 117mSn production

    NASA Astrophysics Data System (ADS)

    Aikawa, M.; Saito, M.; Ukon, N.; Komori, Y.; Haba, H.

    2018-07-01

    The production of 117mSn by charged-particle induced reactions is an interesting topic for medical application. Production cross sections of α-induced reactions on natIn for 117mSn up to 50 MeV were measured using the stacked foil technique and activation method. The integral yield of 117mSn was estimated using the measured cross sections. The results were compared with experimental data investigated earlier and theoretical calculation. Measured cross sections for 113Sn and 116m,117,118mSb isotopes were also presented.

  12. Measurements of Reaction Cross Sections for 9-11C

    NASA Astrophysics Data System (ADS)

    Nishizuka, Kenji; Takechi, Maya; Ohtsubo, Takashi; Nishimura, Daiki; Fukuda, Mitsunori; Aoki, Kazuya; Abe, Keijiro; Ikeda, Ayaka; Izumikawa, Takuji; Oikawa, Hiroyuki; Ohnishi, Kosuke; Ohno, Junichi; Ohmika, Shunichiro; Kato, Ikuma; Kanke, Yuki; Kanbe, Shunsuke; Kanda, Naoto; Kikuchi, Haruka; Kitagawa, Atsushi; Sato, Shinji; Sayama, Umito; Shimaya, Jiro; Sugihara, Takanobu; Suzuki, Shinji; Suzuki, Takeshi; Takahashi, Hiroki; Taguchi, Yoshisada; Takei, Yuki; Takeuchi, Yuki; Takenouchi, Arashi; Takemoto, Takanori; Tadano, Natsuki; Tanaka, Masaomi; Tanaka, Yutaro; Chikaato, Kazuya; Du, Hang; Nagai, Takumi; Nagumo, Junya; Fukuda, Shigekazu; Hori, Kensyu; Honma, Akira; Machida, Masahiro; Matsunaga, Satoshi; Mizukami, Atsushi; Mihara, Mototsugu; Miyata, Eri; Murooka, Daiki; Yagi, Shoichi; Yamaoka, Shintaro; Yamaguchi, Takayuki; Yokoyama, Kouhei

    In order to probe the differences of matter and charge radii of atomic nucleus in the proton-rich C isotopes, measurements of reaction cross sections (σR) for 9-11C on proton targets in the energy range from 50 to 120A MeV were performed at HIMAC facility, NIRS. Owing to the large differences between proton-proton and proton-neutron scattering cross sections at this intermediate energy region, σR data for atomic nuclei on proton targets are expected to have the sensitivity to the differences between proton and neutron distributions in the nucleus. Present preliminary data are compared with the Glauber calculation, which suggest the larger enhancements of proton distributions in 9C and 10C compared to 11C.

  13. Cross section measurement of 14N(p ,γ )15O in the CNO cycle

    NASA Astrophysics Data System (ADS)

    Li, Q.; Görres, J.; deBoer, R. J.; Imbriani, G.; Best, A.; Kontos, A.; LeBlanc, P. J.; Uberseder, E.; Wiescher, M.

    2016-05-01

    Background: The CNO cycle is the main energy source in stars more massive than our sun; it defines the energy production and the cycle time that lead to the lifetime of massive stars, and it is an important tool for the determination of the age of globular clusters. In our sun about 1.6% of the total solar neutrino flux comes from the CNO cycle. The largest uncertainty in the prediction of this CNO flux from the standard solar model comes from the uncertainty in the 14N(p ,γ )15O reaction rate; thus, the determination of the cross section at astrophysical temperatures is of great interest. Purpose: The total cross section of the 14N(p ,γ )15O reaction has large contributions from the transitions to the Ex=6.79 MeV excited state and the ground state of 15O. The Ex=6.79 MeV transition is dominated by radiative direct capture, while the ground state is a complex mixture of direct and resonance capture components and the interferences between them. Recent studies have concentrated on cross-section measurements at very low energies, but broad resonances at higher energy may also play a role. A single measurement has been made that covers a broad higher-energy range but it has large uncertainties stemming from uncorrected summing effects. Furthermore, the extrapolations of the cross section vary significantly depending on the data sets considered. Thus, new direct measurements have been made to improve the previous high-energy studies and to better constrain the extrapolation. Methods: Measurements were performed at the low-energy accelerator facilities of the nuclear science laboratory at the University of Notre Dame. The cross section was measured over the proton energy range from Ep=0.7 to 3.6 MeV for both the ground state and the Ex=6.79 MeV transitions at θlab=0∘ , 45∘, 90∘, 135∘, and 150∘. Both TiN and implanted-14N targets were utilized. γ rays were detected by using an array of high-purity germanium detectors. Results: The excitation function as

  14. Deformation effect in the fast neutron total cross section of aligned /sup 59/Co

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fasoli, U.; Pavan, P.; Toniolo, D.

    1983-05-01

    The variation of the total neutron cross section, ..delta..sigma/sub align/, on /sup 59/Co due to nuclear alignment of the target has been measured over the energy range from 0.8 to 20 MeV employing a cobalt single crystal with a 34% nuclear alignment. The results show that ..delta..sigma/sub align/ oscillates from a minimum of -5% at about 2.5 MeV to a maximum of +1% at about 10 MeV. The data were successfully fitted by optical model coupled-channel calculations. The coupling terms were deduced from a model representing the /sup 59/Co nucleus as a vibrational /sup 60/Ni core coupled to a protonmore » hole in a (1f/sub 7/2/) shell, without free parameters. The optical model parameters were determined by fitting the total cross section, which was independently measured. The theoretical calculations show that, at lower energies, ..delta..sigma/sub align/ depends appreciably on the coupling with the low-lying levels.« less

  15. 3He(γ,pp)n cross sections with tagged photons below the Δ resonance energy

    NASA Astrophysics Data System (ADS)

    Kolb, N. R.; Feldman, G.; O'rielly, G. V.; Pywell, R. E.; Skopik, D. M.; Hackett, E. D.; Quraan, M. A.; Rodning, N. L.

    1996-11-01

    Cross sections have been measured for the 3He(γ,pp)n reaction with tagged photons in the range Eγ =161-208 MeV using the Saskatchewan-Alberta Large Acceptance Detector (SALAD). The protons were detected over a range of polar angles of 40°-140° and azimuthal angles of 0°-360° with an energy threshold of 40 MeV. Comparisons are made with a microscopic calculation which includes one-, two-, and three-nucleon absorption mechanisms. One- and two-nucleon processes, including final-state interactions, are unable to account for the measured cross sections. The addition of three-nucleon absorption diagrams gives roughly the right strength, but the distribution in phase space is in disagreement with the data.

  16. Neutron-induced fission cross-section measurement of 234U with quasi-monoenergetic beams in the keV and MeV range using micromegas detectors

    NASA Astrophysics Data System (ADS)

    Tsinganis, A.; Kokkoris, M.; Vlastou, R.; Kalamara, A.; Stamatopoulos, A.; Kanellakopoulos, A.; Lagoyannis, A.; Axiotis, M.

    2017-09-01

    Accurate data on neutron-induced fission cross-sections of actinides are essential for the design of advanced nuclear reactors based either on fast neutron spectra or alternative fuel cycles, as well as for the reduction of safety margins of existing and future conventional facilities. The fission cross-section of 234U was measured at incident neutron energies of 560 and 660 keV and 7.5 MeV with a setup based on `microbulk' Micromegas detectors and the same samples previously used for the measurement performed at the CERN n_TOF facility (Karadimos et al., 2014). The 235U fission cross-section was used as reference. The (quasi-)monoenergetic neutron beams were produced via the 7Li(p,n) and the 2H(d,n) reactions at the neutron beam facility of the Institute of Nuclear and Particle Physics at the `Demokritos' National Centre for Scientific Research. A detailed study of the neutron spectra produced in the targets and intercepted by the samples was performed coupling the NeuSDesc and MCNPX codes, taking into account the energy spread, energy loss and angular straggling of the beam ions in the target assemblies, as well as contributions from competing reactions and neutron scattering in the experimental setup. Auxiliary Monte-Carlo simulations were performed with the FLUKA code to study the behaviour of the detectors, focusing particularly on the reproduction of the pulse height spectra of α-particles and fission fragments (using distributions produced with the GEF code) for the evaluation of the detector efficiency. An overview of the developed methodology and preliminary results are presented.

  17. Low energy scattering cross section ratios of 14N(p ,p ) 14N

    NASA Astrophysics Data System (ADS)

    deBoer, R. J.; Bardayan, D. W.; Görres, J.; LeBlanc, P. J.; Manukyan, K. V.; Moran, M. T.; Smith, K.; Tan, W.; Uberseder, E.; Wiescher, M.; Bertone, P. F.; Champagne, A. E.; Islam, M. S.

    2015-04-01

    Background: The slowest reaction in the first CNO cycle is 14N(p ,γ ) 15O , therefore its rate determines the overall energy production efficiency of the entire cycle. The cross section presents several strong resonance contributions, especially for the ground-state transition. Some of the properties of the corresponding levels in the 15O compound nucleus remain uncertain, which affects the uncertainty in extrapolating the capture cross section to the low energy range of astrophysical interest. Purpose: The 14N(p ,γ ) 15O cross section can be described by using the phenomenological R matrix. Over the energy range of interest, only the proton and γ -ray channels are open. Since resonance capture makes significant contributions to the 14N(p ,γ ) 15O cross section, resonant proton scattering data can be used to provide additional constraints on the R -matrix fit of the capture data. Methods: A 4 MV KN Van de Graaff accelerator was used to bombard protons onto a windowless gas target containing enriched 14N gas over the proton energy range from Ep=1.0 to 3.0 MeV. Scattered protons were detected at θlab=90 , 120∘, 135∘, 150∘, and 160∘ using ruggedized silicon detectors. In addition, a 10 MV FN Tandem Van de Graaff accelerator was used to accelerate protons onto a solid Adenine (C5H5N5 ) target, of natural isotopic abundance, evaporated onto a thin self-supporting carbon backing, over the energy range from Ep=1.8 to 4.0 MeV. Scattered protons were detected at 28 angles between θlab=30 .4∘ and 167 .7∘ by using silicon photodiode detectors. Results: Relative cross sections were extracted from both measurements. While the relative cross sections do not provide as much constraint as absolute measurements, they greatly reduce the dependence of the data on otherwise significant systematic uncertainties, which are more difficult to quantify. The data are fit simultaneously using an R -matrix analysis and level energies and proton widths are extracted. Even

  18. Pu 236 ( n , f ) , Pu 237 ( n , f ) , and Pu 238 ( n , f ) cross sections deduced from ( p , t ) , ( p , d ) , and ( p , p ' ) surrogate reactions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hughes, R. O.; Beausang, C. W.; Ross, T. J.

    2014-07-01

    The Pu 236(n,f), Pu 237(n,f) and Pu 238(n,f) cross sections have been inferred by utilizing the surrogate ratio method. Targets of Pu 239 and U 235 were bombarded with 28.5-MeV protons, and the light ion recoils, as well as fission fragments, were detected using the STARS detector array at the K150 Cyclotron at the Texas A&M cyclotron facility. The (p, tf) reaction on Pu 239 and U 235 targets was used to deduce the σ (Pu 236(n,f))/σ(U 232(n,f)) ratio, and the Pu 236(n,f) cross section was subsequently determined for En=0.5–7.5 MeV. Similarly, the (p,df) reaction on the same two targetsmore » was used to deduce the σ(Pu 237(n,f))/σ(U 233(n,f)) ratio, and the Pu 237(n,f) cross section was extracted in the energy range En=0.5–7 MeV. The Pu 238(n,f) cross section was also deduced by utilizing the (p,p') reaction channel on the same targets. There is good agreement with the recent ENDF/B-VII.1 evaluated cross section data for Pu 238(n,f) in the range En=0.5–10.5 MeV and for Pu 237(n,f) in the range En=0.5–7 MeV; however, the Pu 236(n,f) cross section deduced in the present work is higher than the evaluation between 2 and 7 MeV.« less

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

    DOE PAGES

    Gooden, M. E.; Bredeweg, T. A.; Champine, B.; ...

    2017-08-01

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

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gooden, M. E.; Bredeweg, T. A.; Champine, B.

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

  1. Relativistic three-dimensional Lippmann-Schwinger cross sections for space radiation applications

    NASA Astrophysics Data System (ADS)

    Werneth, C. M.; Xu, X.; Norman, R. B.; Maung, K. M.

    2017-12-01

    Radiation transport codes require accurate nuclear cross sections to compute particle fluences inside shielding materials. The Tripathi semi-empirical reaction cross section, which includes over 60 parameters tuned to nucleon-nucleus (NA) and nucleus-nucleus (AA) data, has been used in many of the world's best-known transport codes. Although this parameterization fits well to reaction cross section data, the predictive capability of any parameterization is questionable when it is used beyond the range of the data to which it was tuned. Using uncertainty analysis, it is shown that a relativistic three-dimensional Lippmann-Schwinger (LS3D) equation model based on Multiple Scattering Theory (MST) that uses 5 parameterizations-3 fundamental parameterizations to nucleon-nucleon (NN) data and 2 nuclear charge density parameterizations-predicts NA and AA reaction cross sections as well as the Tripathi cross section parameterization for reactions in which the kinetic energy of the projectile in the laboratory frame (TLab) is greater than 220 MeV/n. The relativistic LS3D model has the additional advantage of being able to predict highly accurate total and elastic cross sections. Consequently, it is recommended that the relativistic LS3D model be used for space radiation applications in which TLab > 220MeV /n .

  2. Experimental Cross Sections of Fission Fragments of Thorium-232 Irradiated with Medium-Energy Protons

    NASA Astrophysics Data System (ADS)

    Libanova, O. N.; Golubeva, E. S.; Ermolaev, S. V.; Matushko, V. L.; Botvina, A. S.

    2018-05-01

    This paper is focused on fission of Th-232 nuclei induced by protons with energies ranging from 20 to 140 MeV. This energy range is the most informative for studying the competition between asymmetric and symmetric fission modes. Experimental cross sections of production of radionuclides in thorium targets have been determined a year after irradiation. The corresponding theoretical values are calculated using the cascade-evaporation-fission model. The theoretical and experimental cross sections (literature data included) are compared.

  3. Cross Sections of the 36Ar(d,α)34mCl, 40Ar(d,α)38Cl and 40Ar(d,p)41Ar Nuclear Reactions below 8.4 MeV

    PubMed Central

    Engle, J W; Severin, G W; Barnhart, T E; Knutson, L D; Nickles, R J

    2011-01-01

    We have measured the cross section for production of the medically interesting isotope 34mCl, along with 38Cl and 41Ar, using deuteron bombardments of 36Ar and 40Ar below 8.4 MeV. ALICE/ASH analytical codes were employed to determine the shape of nuclear excitation functions, and experiments were performed using the University of Wisconsin tandem electrostatic accelerator to irradiate thin targets of argon gas. PMID:22041299

  4. Designing an upgrade of the Medley setup for light-ion production and fission cross-section measurements

    NASA Astrophysics Data System (ADS)

    Jansson, K.; Gustavsson, C.; Al-Adili, A.; Hjalmarsson, A.; Andersson-Sundén, E.; Prokofiev, A. V.; Tarrío, D.; Pomp, S.

    2015-09-01

    Measurements of neutron-induced fission cross-sections and light-ion production are planned in the energy range 1-40 MeV at the upcoming Neutrons For Science (NFS) facility. In order to prepare our detector setup for the neutron beam with continuous energy spectrum, a simulation software was written using the Geant4 toolkit for both measurement situations. The neutron energy range around 20 MeV is troublesome when it comes to the cross-sections used by Geant4 since data-driven cross-sections are only available below 20 MeV but not above, where they are based on semi-empirical models. Several customisations were made to the standard classes in Geant4 in order to produce consistent results over the whole simulated energy range. Expected uncertainties are reported for both types of measurements. The simulations have shown that a simultaneous precision measurement of the three standard cross-sections H(n,n), 235U(n,f) and 238U(n,f) relative to each other is feasible using a triple layered target. As high resolution timing detectors for fission fragments we plan to use Parallel Plate Avalanche Counters (PPACs). The simulation results have put some restrictions on the design of these detectors as well as on the target design. This study suggests a fissile target no thicker than 2 μm (1.7 mg/cm2) and a PPAC foil thickness preferably less than 1 μm. We also comment on the usability of Geant4 for simulation studies of neutron reactions in this energy range.

  5. Neutrino-nucleus cross sections for oscillation experiments

    NASA Astrophysics Data System (ADS)

    Katori, Teppei; Martini, Marco

    2018-01-01

    Neutrino oscillations physics is entering an era of high precision. In this context, accelerator-based neutrino experiments need a reduction in systematic errors to the level of a few percent. Today, one of the most important sources of systematic errors are neutrino-nucleus cross sections which, in the energy region of hundreds of MeV to a few GeV, are known to a precision not exceeding 20%. In this article we review the present experimental and theoretical knowledge of neutrino-nucleus interaction physics. After introducing neutrino-oscillation physics and accelerator-based neutrino experiments, we give an overview of general aspects of neutrino-nucleus cross sections, from both the theoretical and experimental point of view. Then, we focus on these cross sections in different reaction channels. We start with the quasi-elastic and quasi-elastic-like cross section, placing a special emphasis on the multinucleon emission channel, which has attracted a lot of attention in the last few years. We review the main aspects of the different microscopic models for this channel by discussing analogies and the differences among them. The discussion is always driven by a comparison with the experimental data. We then consider the one-pion production channel where agreement between data and theory remains highly unsatisfactory. We describe how to interpret pion data, and then analyze, in particular, the puzzle related to the difficulty of theoretical models and Monte Carlo to simultaneously describe MiniBooNE and MINERvA experimental results. Inclusive cross sections are also discussed, as well as the comparison between the {ν }μ and {ν }e cross sections, relevant for the charge-conjugation-parity violation experiments. The impact of nuclear effects on the reconstruction of neutrino energy and on the determination of the neutrino-oscillation parameters is also reviewed. Finally, we look to the future by discussing projects and efforts in relation to future detectors, beams

  6. The 75As(n,2n) Cross Sections into the 74As Isomer and Ground State

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Younes, W; Garrett, P E; Becker, J A

    2003-06-30

    The {sup 75}As(n, 2n) cross section for the population of the T{sub 1/2} = 26.8-ns isomer at E{sub x} = 259.3 keV in {sup 74}As has been measured as a function of incident neutron energy, from threshold to E{sub n} = 20 MeV. The cross section was measured using the GEANIE spectrometer at LANSCE/WNR. For convenience, the {sup 75}As(n, 2n) population cross section for the {sup 74}As ground state has been deduced as the difference between the previously-known (n, 2n) reaction cross section and the newly measured {sup 75}As(n, 2n){sup 74}As{sup m} cross section. The (n, 2n) reaction, ground-state, andmore » isomer population cross sections are tabulated in this paper.« less

  7. Experimental study of the energy dependence of the total cross section for the 6He + natSi and 9Li + natSi reactions

    NASA Astrophysics Data System (ADS)

    Sobolev, Yu. G.; Penionzhkevich, Yu. E.; Aznabaev, D.; Zemlyanaya, E. V.; Ivanov, M. P.; Kabdrakhimova, G. D.; Kabyshev, A. M.; Knyazev, A. G.; Kugler, A.; Lashmanov, N. A.; Lukyanov, K. V.; Maj, A.; Maslov, V. A.; Mendibayev, K.; Skobelev, N. K.; Slepnev, R. S.; Smirnov, V. V.; Testov, D.

    2017-11-01

    New experimental measurements of the total reaction cross sections for the 6He + natSi and 9Li + natSi processes in the energy range of 5 to 40 A MeV are presented. A modified transmission method based on high-efficiency detection of prompt n-γ radiation has been used in the experiment. A bump is observed for the first time in the energy dependence σR( E) at E ˜ 10-30 A MeV for the 9Li + natSi reaction, and existence of the bump in σR( E) at E ˜ 10-20 A MeV first observed in the standard transmission experiments is experimentally confirmed for the 6He + natSi reaction. Theoretical analysis of the measured 6He + natSi and 9Li + natSi reaction cross sections is performed within the microscopic double folding model. Disagreement is observed between the experimental and theoretical cross sections in the region of the bump at the energies of 10 to 20 A MeV, which requires further study.

  8. Cross sections of the 36Ar(d,α)34mCl, 40Ar(d,α)38Cl, and 40Ar(d,p)41Ar nuclear reactions below 8.4 MeV.

    PubMed

    Engle, J W; Severin, G W; Barnhart, T E; Knutson, L D; Nickles, R J

    2012-02-01

    We have measured the cross section for production of the medically interesting isotope (34m)Cl, along with (38)Cl and (41)Ar, using deuteron bombardments of (36)Ar and (40)Ar below 8.4 MeV. ALICE/ASH analytical codes were employed to determine the shape of nuclear excitation functions, and experiments were performed using the University of Wisconsin tandem electrostatic accelerator to irradiate thin targets of argon gas. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. Measurement of differential cross section of D(3He,p)4He from 0.8 MeV to 3.6 MeV

    NASA Astrophysics Data System (ADS)

    Zhu, J. P.; Xiao, X.; Yan, S.; Gao, Y.; Xue, J. M.; Wang, Y. G.

    2017-12-01

    Precise knowledge of the nuclear reaction cross-section is crucial for nuclear reaction analysis methods and its applications. In order to apply nuclear reaction analysis methods to Plasma Facing Materials studies on 4.5 MV electrostatic accelerator at Peking University, differential cross-section for d(3He,p) α at several backward angles was measured with a relative error about ± 6.2 % , gives detailed information at the laboratory angle of 135° from 800 keV to 3600 keV, as well as a rough angular distribution from 130° to 160°.

  10. Evaluated activation cross sections of longer-lived radionuclides produced by deuteron-induced reactions on natural copper

    NASA Astrophysics Data System (ADS)

    Takács, S.; Tárkányi, F.; Király, B.; Hermanne, A.; Sonck, M.

    2006-09-01

    Activation cross sections for deuteron-induced reactions on natural copper were measured by using a standard stacked foil technique up to 50 MeV deuteron bombarding energy. Reaction products with half-life longer than half an hour were studied. Experimental elemental cross sections were determined and compared with earlier measured data for 62,63,65Zn, 64Cu, 57,65Ni, 57,58,60Co and 59Fe isotopes.

  11. Measurements of Interaction Cross Sections for 19-27F Isotopes

    NASA Astrophysics Data System (ADS)

    Homma, Akira; Takechi, Maya; Ohtsubo, Takashi; Nishimura, Daiki; Fukuda, Mitsunori; Suzuki, Takeshi; Yamaguchi, Takayuki; Kuboki, Takamasa; Ozawa, Akira; Suzuki, Sinji; Ooishi, Hiroto; Moriguchi, Tetsuaki; Sumikawa, Takashi; Geissel, H.; Aoi, Nori; Chen, Rui-jiu; Fang, De-Qing; Fukuda, Naoki; Fukuoka, Shota; Furuki, Hisahiro; Inaba, Naruki; Ishibashi, Nobuyuki; Ito, Takeshi; Izumikawa, Takuji; Kameda, Daisuke; Kubo, Toshiyuki; Lantz, M.; Lee, C. S.; Ma, Yu-Gang; Mihara, Mototsugu; Momota, Satao; Nagae, Daisuke; Nishikiori, Ryo; Niwa, Takahiro; Ohnishi, Tetsuya; Okumura, Kimitake; Ogura, Toshiyuki; Nagashima, Masayuki; Sakurai, Hiroyoshi; Sato, Kanae; Shimbara, Yoshiriro; Suzuki, Hiroshi; Takeda, Hiroyuki; Takeuchi, Satoshi; Tanaka, Kenji; Uenishi, Hideaki; Winkler, M.; Yanagisawa, Yoshiyuki

    Interaction cross sections (σI) and reaction cross sections (σR) are physical quantities which are strongly related to the nuclear size. In our previous study of σI for Ne isotopes, the deformation features of neutron-rich Ne isotopes in the so-called "island of inversion" region have been successfully observed, and also the formation of the deformed halo structure in 31Ne has been indicated. In this study, σI for 19-27F, up to the vicinity of the island of inversion have been measured at around 240A MeV using BigRIPS at RIBF, RIKEN. Our preliminary results are slightly larger than A1/3 systematics and some of the data could be explained by nuclear deformation.

  12. Measurement of the scattering cross section of slow neutrons on liquid parahydrogen from neutron transmission

    DOE PAGES

    Grammer, K. B.; Alarcon, R.; Barrón-Palos, L.; ...

    2015-05-08

    Liquid hydrogen is a dense Bose fluid whose equilibrium properties are both calculable from first principles using various theoretical approaches and of interest for the understanding of a wide range of questions in many-body physics. Unfortunately, the pair correlation function g(r) inferred from neutron scattering measurements of the differential cross section dσ/dΩ from different measurements reported in the literature are inconsistent. We have measured the energy dependence of the total cross section and the scattering cross section for slow neutrons with energies between 0.43 and 16.1 meV on liquid hydrogen at 15.6 K (which is dominated by the parahydrogen component)more » using neutron transmission measurements on the hydrogen target of the NPDGamma collaboration at the Spallation Neutron Source at Oak Ridge National Laboratory. The relationship between the neutron transmission measurement we perform and the total cross section is unambiguous, and the energy range accesses length scales where the pair correlation function is rapidly varying. At 1 meV our measurement is a factor of 3 below the data from previous work. We present evidence that these previous measurements of the hydrogen cross section, which assumed that the equilibrium value for the ratio of orthohydrogen and parahydrogen has been reached in the target liquid, were in fact contaminated with an extra nonequilibrium component of orthohydrogen. Liquid parahydrogen is also a widely used neutron moderator medium, and an accurate knowledge of its slow neutron cross section is essential for the design and optimization of intense slow neutron sources. Furthermore, we describe our measurements and compare them with previous work.« less

  13. The differential production cross section of the $$\\phi $$ (1020) meson in $$\\sqrt{s}$$ TeV $pp$ collisions measured with the ATLAS detector

    DOE PAGES

    Aad, G.; Abajyan, T.; Abbott, B.; ...

    2014-07-01

    Ameasurement is presented of themore » $$\\phi $$×BR($$\\phi $$ →K < sup > + < /sup > K < sup > - < /sup > ) production cross section at √s = 7 TeV using pp collision data corresponding to an integrated luminosity of 383 μb -1, collected with the ATLAS experiment at the HC. Selection of $$\\phi $$(1020) mesons is based on the identification of charged kaons by their energy loss in the pixel detector. The differential cross section ismeasured as a function of the transverse momentum, pT,$$\\phi $$ , and rapidity, y$$\\phi $$, of the $$\\phi $$(1020) meson in the fiducial region 500 < pT,$$\\phi $$ < 1200MeV, |y$$\\phi $$ | < 0.8, kaon p T,K > 230 MeV and kaon momentum p K < 800 MeV. The integrated $$\\phi $$(1020)-meson production cross section in this fiducial range is measured to be sφ×BR($$\\phi $$ →K < sup > + < /sup > K < sup > - < /sup > ) = 570 ± 8 (stat) ± 66 (syst) ± 20 (lumi) μb.« less

  14. Exploring the anomaly in the interaction cross section and matter radius of (23)O

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kanungo, R.; Uchida, M.; Perro, C.

    New measurements of the interaction cross sections of {sup 22,23}O at 900A MeV performed at the GSI, Darmstadt are reported that address the unsolved puzzle of the large cross section previously observed for {sup 23}O. The matter radii for these oxygen isotopes extracted through a Glauber model analysis are in good agreement with the new predictions of the ab initio coupled-cluster theory reported here. They are consistent with a {sup 22}O + neutron description of {sup 23}O as well.

  15. Cross sections of the 144Sm(n,α)141Nd and 66Zn(n,α)63Ni reactions at 4.0, 5.0 and 6.0 MeV

    NASA Astrophysics Data System (ADS)

    Yury, Gledenov; Guohui, Zhang; Khuukhenkhuu, Gonchigdorj; Milana, Sedysheva; Lubos, Krupa; Sansarbayar, Enkhbold; Igor, Chuprakov; Zhimin, Wang; Xiao, Fan; Luyu, Zhang; Huaiyong, Bai

    2017-09-01

    Cross sections of the 144Sm(n,α)141Nd and 66Zn(n,α)63Ni reactions were measured at En = 4.0, 5.0 and 6.0 MeV performed at the 4.5-MV Van de Graaff Accelerator of Peking University, China. A double-section gridded ionization chamber was used to detect the alpha particles. The foil samples of 144Sm2O3 and enriched 66Zn were placed at the common cathode plate of the chamber. Monoenergetic neutrons were produced by a deuterium gas target through the 2H(d,n)3He reaction. The neutron flux was monitored by a BF3 long counter. Cross sections of the 238U(n,f) reaction were used as the standard to perform the (n,α) reaction measurement. Present results are compared with existing measurements and evaluations. They are generally in agreement with TALYS-1.6 code calculations. For the 144Sm(n,α)141Nd reaction our measurements support the data of JEF-2.2. For the 66Zn(n,α)63Ni reaction present results support the data of EAF-2010 and TENDL-2015 data.

  16. Cross-Section Measurements of the Kr86(γ,n) Reaction to Probe the s-Process Branching at Kr85

    NASA Astrophysics Data System (ADS)

    Raut, R.; Tonchev, A. P.; Rusev, G.; Tornow, W.; Iliadis, C.; Lugaro, M.; Buntain, J.; Goriely, S.; Kelley, J. H.; Schwengner, R.; Banu, A.; Tsoneva, N.

    2013-09-01

    We have carried out photodisintegration cross-section measurements on Kr86 using monoenergetic photon beams ranging from the neutron separation energy, Sn=9.86MeV, to 13 MeV. We combine our experimental Kr86(γ,n)Kr85 cross section with results from our recent Kr86(γ,γ') measurement below the neutron separation energy to obtain the complete nuclear dipole response of Kr86. The new experimental information is used to predict the neutron capture cross section of Kr85, an important branching point nucleus on the abundance flow path during s-process nucleosynthesis. Our new and more precise Kr85(n,γ)Kr86 cross section allows us to produce more precise predictions of the Kr86 abundance from s-process models. In particular, we find that the models of the s process in asymptotic giant branch stars of mass <1.5M⊙, where the C13 neutron source burns convectively rather than radiatively, represent a possible solution for the highest Kr86∶Kr82 ratios observed in meteoritic stardust SiC grains.

  17. Reaction mechanisms in 12C(γ,pp) near 200 MeV

    NASA Astrophysics Data System (ADS)

    Hackett, E. D.; McDonald, W. J.; Opper, A. K.; Quraan, M. A.; Rodning, N. L.; Rozon, F. M.; Feldman, G.; Kolb, N. R.; Pywell, R. E.; Skopik, D. M.; Tiller, D. E.; Vogt, J. M.; Korkmaz, E.; O'rielly, G. V.

    1996-03-01

    Inclusive 12C(γ,pp) cross sections have been measured with tagged photons in the range Eγ=187-227 MeV using the Saskatchewan-Alberta Large Acceptance Detector (SALAD). The large angular acceptance allowed the measurement of noncoplanar pp emission. The cross sections were compared to a Monte Carlo intranuclear cascade calculation. Agreement was reasonable for the shapes of the cross sections but the calculated total cross section was 3.9 times larger than the data.

  18. Neutron scattering measurements in {sup 197}Au from 850 keV to 2.0 MeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    O`Connor, M.; Chen, J.; Egan, J.J.

    1995-10-01

    Differential elastic and inelastic neutron scattering cross-sections for low lying levels in {sup 197}Au have been measured for incident neutron energies of 1.0 MeV, 1.5 MeV and 2.0 MeV. In addition, the total neutron cross sections in {sup 197}Au was measured from 850 keV to 1.5 MeV. For both experiments the UML 5.5 MV Van-de-Graaff accelerator with a Mobley post acceleration compression system, produced subnanosecond proton pulses which generated neutrons via the {sup 7}Li(p,n) {sup 7}Be reaction.

  19. Stopping cross sections of He + ions in bismuth

    NASA Astrophysics Data System (ADS)

    Kuldeep; Jain, Animesh K.

    1985-06-01

    The stopping cross sections, ɛ( E), of He + ions in bismuth have been measured by Rutherford backscattering spectrometry (RBS) at incident energies ranging from E = 1.6-3.4 MeV. The energy loss of He + ions and thicknesses of the bismuth films deposited on aluminium substrates were determined from the RBS spectra at each energy for scattering angles of 130° and 165°. The film thicknesses of some of the samples were also measured by weighing and the results compared with those from RBS. Parameters for energy dependence of stopping cross section in the Varelas-Biersack interpolation formula have been obtained for bismuth from a fit to all the available experimental data. Accuracy of our method based on RBS is demonstrated by measurements on copper, for which ɛ( E) is already well studied. It is also shown that reliable ɛ( E) values may be obtained even on samples with non-uniform film thickness.

  20. 7Li(p,n)7Be and 12C(p,n)12N reactions at 200, 300, and 400 MeV

    NASA Astrophysics Data System (ADS)

    Watson, J. W.; Pourang, R.; Abegg, R.; Alford, W. P.; Celler, A.; El-Kateb, S.; Frekers, D.; Häusser, O.; Helmer, R.; Henderson, R.; Hicks, K.; Jackson, K. P.; Jeppesen, R. G.; Miller, C. A.; Vetterli, M.; Yen, S.; Zafiratos, C. D.

    1989-07-01

    At 200, 300, and 400 MeV bombarding energies, we measured cross section angular distributions for the 7Li(p,n)7Be(g.s.+0.43 MeV) reaction and 0° cross sections for the 12C(p,n)12N(g.s.) reaction. Systematics of these reactions are presented. The center-of-mass cross section for the 7Li(p,n)7Be(g.s.+0.43 MeV) reaction, when plotted as a function of momentum transfer, is nearly independent of energy. The laboratory cross section for this reaction at 0° in the energy range from 60 to 400 MeV is also independent of energy, having a constant value, to within experimental errors, of 35.5 mb/sr with an estimated uncertainty of +/-1.5 mb/sr.

  1. Study of p-4He total reaction cross-section using Glauber and Coulomb-modified Glauber models

    NASA Astrophysics Data System (ADS)

    Tag El-Din, Ibrahim M. A.; Taha, M. M.; Hassan, Samia S. A.

    2014-02-01

    The total nuclear reaction cross-section σR for p-4He in the energy range from 25 MeV to 1000 MeV is calculated within Glauber and Coulomb-modified Glauber models. The Coulomb-modified Glauber model (CMGM) is introduced via modification of the Coulomb trajectory of the projectile from a straight line, and calculation of the effective radius of interaction. The effects of in-medium nucleon-nucleon (NN) total cross-section, phase variation, high order momentum transfer component of nucleon-nucleon elastic scattering amplitude and Pauli blocking are studied. It is pointed out that the phase variation of the nucleon-nucleon amplitude plays a significant role in describing σR with γ = -1.6 fm2 at in-medium nuclear density ϱ = 0 and γ = -2 fm2 at ϱ = 0.17 fm-3 in the whole energy range. A remarkable fit to the available experimental data is obtained by invoking Pauli blocking and high order momentum transfer of nucleon-nucleon (NN) elastic scattering amplitude for Ep < 100 MeV.

  2. Measurement of the cross section for the 4He(α, n)7Be reaction as a possible solution to the cosmological lithium problem

    NASA Astrophysics Data System (ADS)

    Kawabata, T.; Furuno, T.; Ichikawa, M.; Iwasa, N.; Kanada-En'yo, Y.; Koshikawa, A.; Kubono, S.; Miyawaki, E.; Morimoto, T.; Murata, M.; Nanamura, T.; Nishimura, S.; Shikata, Y.; Takahashi, Y.; Takeda, T.; Tsumura, M.; Watanabe, K.

    2017-06-01

    The cross section for the 4He(α,n)7Be reaction was measured at low energies between Eα = 38.50 and 39.64 MeV motivated by the cosmological lithium problem. On the basis of the detailed balance principle, the cross section for the 7Be(n,α)4He reaction was obtained at Ec.m. = 0.20-0.81 MeV close to the Big Bang nucleosynthesis (BBN) energy window for the first time. The obtained cross sections are significantly smaller than the theoretical estimation widely used in the BBN calculations. The present results suggest the 7Be(n,α)4He reaction rate is not large enough to solve the cosmological lithium problem.

  3. Precise 238U(n,2n)237U reaction cross-section measurements using the activation facility at TUNL

    NASA Astrophysics Data System (ADS)

    Krishichayan, Fnu; Bhike, M.; Tornow, W.

    2014-09-01

    Accurate neutron-induced 238U(n,2n)237U reaction data are required for many practical applications, especially in the field of nuclear energy, including advanced heavy water reactors, where 238U is used as the breeding material to regenerate the fissile material 239Pu. Precise (n,2n) cross-section measurements of 238U are underway at TUNL with mono-energetic neutrons in the 8.0 to 14.0 MeV energy range in steps of 0.25 MeV using the activation technique. After activation of the 0.5 inch diameter and 442 mg 238U foil, the activity of the 208 keV characteristic γ-line is tracked for 6 weeks with a high efficient HPGe clover detector to determine the initial activity needed for the cross-section determination. Results of the cross-section measurements, determined relative to 27Al and 197Au neutron activation monitor foils, and the comparison with theoretical models will be presented during the meeting.

  4. 3He(γ,pd) cross sections with tagged photons below the Δ resonance

    NASA Astrophysics Data System (ADS)

    Kolb, N. R.; Cairns, E. B.; Hackett, E. D.; Korkmaz, E.; Nakano, T.; Opper, A. K.; Quraan, M. A.; Rodning, N. L.; Rozon, F. M.; Asai, J.; Feldman, G.; Hallin, E.; O'rielly, G. V.; Pywell, R. E.; Skopik, D. M.

    1994-05-01

    The reaction cross section for 3He(γ,pd) has been measured using the Saskatchewan-Alberta Large Acceptance Detector (SALAD) with tagged photons in the energy range from 166 to 213 MeV. The energy and angle of the proton and the deuteron were measured with SALAD while the tagger determined the photon energy. Differential cross sections have been determined for 40°<θ*p<150°. The results are in agreement with the Bonn and Saclay photodisintegration measurements. The most recent photodisintegration measurement performed at Bates is higher by a factor of 1.3, which is just within the combined errors of the experiments. The proton capture results differ by a factor of 1.7 from the present experiment. Comparisons are made with microscopic calculations of the cross sections.

  5. Collision energy-resolved study of the emission cross-section and the Penning ionization cross-section in the reaction of BrCN with He*(2 3S)

    NASA Astrophysics Data System (ADS)

    Kanda, Kazuhiro; Yamakita, Yoshihiro; Ohno, Koichi

    2001-12-01

    The dissociative excitation of BrCN producing CN(B 2Σ +) fragment by the collision of He *(2 3S) was investigated by the collision energy-resolved electron and emission spectroscopy using time-of-flight method with a high-intensity He * beam. The Penning electrons ejected from BrCN and the subsequent CN ( B2Σ +- X2Σ +) emission were measured as a function of collision energy in the range of 90-180 meV. The formation of CN ( B2Σ +) is concluded to proceed dominantly via the promotion of an electron from Π-character orbital, by comparison between the collision energy dependence of the partial Penning ionization cross-sections and the CN ( B2Σ +- X2Σ +) emission cross-section.

  6. Activation cross-section measurement of proton induced reactions on cerium

    NASA Astrophysics Data System (ADS)

    Tárkányi, F.; Hermanne, A.; Ditrói, F.; Takács, S.; Spahn, I.; Spellerberg, S.

    2017-12-01

    In the framework of a systematic study of proton induced nuclear reactions on lanthanides we have measured the excitation functions on natural cerium for the production of 142,139,138m,137Pr, 141,139,137m,137g,135Ce and 133La up to 65 MeV proton energy using the activation method with stacked-foil irradiation technique and high-resolution γ-ray spectrometry. The cross-sections of the investigated reactions were compared with the data retrieved from the TENDL-2014 and TENDL-2015 libraries, based on the latest version of the TALYS code system. No earlier experimental data were found in the literature. The measured cross-section data are important for further improvement of nuclear reaction models and for practical applications in nuclear medicine, other labeling and activation studies.

  7. Recent cross-section measurements of neutron-induced reactions of importance for background estimates in 0νββ searches

    NASA Astrophysics Data System (ADS)

    Tornow, W.; Bhike, M.; Finch, S. W.; Krishichayan

    2017-09-01

    We report on cross-section measurements for the reactions 76Ge(n,2n)75Ge, 76Ge(n,n'γ)76Ge, 126,127,128Te(n,γ)127,129,131Te, and 136Xe(n,n'γ)136Xe in the neutron energy range between 0.5 MeV and 15 MeV.

  8. Measurements of cross sections for the 209Bi(n, 4n) reaction by using high energy neutrons with continuous energy spectra

    NASA Astrophysics Data System (ADS)

    Min, Kyung Joo; Bak, Sang-In; Ham, Cheolmin; In, Eun Jin; Kim, Do Yoon; Myung, Hyunjeong; Shim, Chungbo; Shin, Jae Won; Zhou, Yujie; Park, Tae-Sun; Hong, Seung-Woo; Bhoraskar, V. N.

    2017-09-01

    We measured 209Bi(n, 4n) cross sections at neutron energies En = 29.8 ± 1.8 MeV and En = 34.8 ± 1.8 MeV. Bismuth oxide samples were irradiated with the neutrons produced by impinging 30, 35 and 40 MeV proton beams on a 1.05 cm thick beryllium target, where the proton beams were from the MC-50 Cyclotron of Korea Institute of Radiological Medical Sciences (KIRAMS). The neutron flux for each proton beam energy Ep, ΦEp(En), has a broad spectrum with respect to En. By taking the difference in the neutron fluxes, the difference spectra, Φ40(En) -Φ35(En) and Φ35(En) -Φ30(En), are obatined and found to be peaked at En = 29.8 and 34.8 MeV, respectively, with a width of about 3.6 MeV. By making use of this observation and employing the TENDL-2009 library we could extract the 209Bi(n, 4n)206Bi cross sections at the aforementioned neutron energies.

  9. Activation cross sections of α-induced reactions on natZn for Ge and Ga production

    NASA Astrophysics Data System (ADS)

    Aikawa, M.; Saito, M.; Ebata, S.; Komori, Y.; Haba, H.

    2018-07-01

    The production cross sections of 68,69Ge and 66,67Ga by α-induced reactions on natZn have been measured using the stacked-foil activation method and off-line γ-ray spectrometry from their threshold energies to 50.7 MeV. The derived cross sections were compared with the previous experimental data and the calculated values in the TENLD-2017 library. Our result shows a slightly larger amplitude than the previous data at the peak, though the peak energy is consistent with them.

  10. Precision Measurement of the e+e-→Λc+Λ¯c - Cross Section Near Threshold

    NASA Astrophysics Data System (ADS)

    Ablikim, M.; Achasov, M. N.; Ahmed, S.; Albrecht, M.; Alekseev, M.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Bai, Y.; Bakina, O.; Baldini Ferroli, R.; Ban, Y.; Begzsuren, K.; Bennett, D. W.; Bennett, J. V.; Berger, N.; Bertani, M.; Bettoni, D.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chai, J.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, J. C.; Chen, M. L.; Chen, P. L.; Chen, S. J.; Chen, X. R.; Chen, Y. B.; Chu, X. K.; Cibinetto, G.; Cossio, F.; Dai, H. L.; Dai, J. P.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; de Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Dou, Z. L.; Du, S. X.; Duan, P. F.; Fang, J.; Fang, S. S.; Fang, Y.; Farinelli, R.; Fava, L.; Fegan, S.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. L.; Gao, Y.; Gao, Y. G.; Gao, Z.; Garillon, B.; Garzia, I.; Gilman, A.; Goetzen, K.; Gong, L.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guo, A. Q.; Guo, R. P.; Guo, Y. P.; Guskov, A.; Haddadi, Z.; Han, S.; Hao, X. Q.; Harris, F. A.; He, K. L.; He, X. Q.; Heinsius, F. H.; Held, T.; Heng, Y. K.; Holtmann, T.; Hou, Z. L.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, X. Z.; Huang, Z. L.; Hussain, T.; Ikegami Andersson, W.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, X. S.; Jiang, X. Y.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Jin, Y.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Khan, T.; Khoukaz, A.; Kiese, P.; Kliemt, R.; Koch, L.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kuemmel, M.; Kuhlmann, M.; Kupsc, A.; Kühn, W.; Lange, J. S.; Lara, M.; Larin, P.; Lavezzi, L.; Leithoff, H.; Li, C.; Li, Cheng; Li, D. M.; Li, F.; Li, F. Y.; Li, G.; Li, H. B.; Li, H. J.; Li, J. C.; Li, J. W.; Li, Jin; Li, K. J.; Li, Kang; Li, Ke; Li, Lei; Li, P. L.; Li, P. R.; Li, Q. Y.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Libby, J.; Lin, C. X.; Lin, D. X.; Liu, B.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. L.; Liu, H. M.; Liu, Huanhuan; Liu, Huihui; Liu, J. B.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, Ke; Liu, L. D.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqing; Long, Y. F.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, X. L.; Lusso, S.; Lyu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, M. M.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Ma, Y. M.; Maas, F. E.; Maggiora, M.; Malik, Q. A.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Meng, Z. X.; Messchendorp, J. G.; Mezzadri, G.; Min, J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales Morales, C.; Muchnoi, N. Yu.; Muramatsu, H.; Mustafa, A.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Papenbrock, M.; Patteri, P.; Pelizaeus, M.; Pellegrino, J.; Peng, H. P.; Peng, Z. Y.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Pitka, A.; Poling, R.; Prasad, V.; Qi, H. R.; Qi, M.; Qi, T. Y.; Qian, S.; Qiao, C. F.; Qin, N.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Richter, M.; Ripka, M.; Rolo, M.; Rong, G.; Rosner, Ch.; Sarantsev, A.; Savrié, M.; Schnier, C.; Schoenning, K.; Shan, W.; Shan, X. Y.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Shi, X.; Song, J. J.; Song, W. M.; Song, X. Y.; Sosio, S.; Sowa, C.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, L.; Sun, S. S.; Sun, X. H.; Sun, Y. J.; Sun, Y. K.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tan, Y. T.; Tang, C. J.; Tang, G. Y.; Tang, X.; Tapan, I.; Tiemens, M.; Tsednee, B.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, Dan; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, Meng; Wang, P.; Wang, P. L.; Wang, W. P.; Wang, X. F.; Wang, Y.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. Y.; Wang, Zongyuan; Weber, T.; Wei, D. H.; Wei, J. H.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, L. J.; Wu, Z.; Xia, L.; Xia, Y.; Xiao, D.; Xiao, Y. J.; Xiao, Z. J.; Xie, Y. G.; Xie, Y. H.; Xiong, X. A.; Xiu, Q. L.; Xu, G. F.; Xu, J. J.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Yan, F.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y. H.; Yang, Y. X.; Yang, Yifan; Ye, M.; Ye, M. H.; Yin, J. H.; You, Z. Y.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yuan, C. Z.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zeng, Y.; Zeng, Z.; Zhang, B. X.; Zhang, B. Y.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. Q.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. T.; Zhang, Yang; Zhang, Yao; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, Q.; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, A. N.; Zhu, J.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zou, B. S.; Zou, J. H.; Besiii Collaboration

    2018-03-01

    The cross section of the e+e-→Λc+Λ¯c - process is measured with unprecedented precision using data collected with the BESIII detector at √{s }=4574.5 , 4580.0, 4590.0 and 4599.5 MeV. The nonzero cross section near the Λc+Λ¯c- production threshold is cleared. At center-of-mass energies √{s }=4574.5 and 4599.5 MeV, the higher statistics data enable us to measure the Λc polar angle distributions. From these, the Λc electric over magnetic form-factor ratios (|GE/GM|) are measured for the first time. They are found to be 1.14 ±0.14 ±0.07 and 1.23 ±0.05 ±0.03 , respectively, where the first uncertainties are statistical and the second are systematic.

  11. Precision Measurement of the e + e - → Λ c + Λ ¯ c - Cross Section Near Threshold

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ablikim, M.; Achasov, M. N.; Ahmed, S.

    The cross section of the e +e - →more » $$Λ_c^+$$$\\bar{Λ}$$$_c^-$$ process is measured with unprecedented precision using data collected with the BESIII detector at √s = 4574.5, 4580.0, 4590.0 and 4599.5 MeV. The non-zero cross section near the $$Λ_c^+$$$\\bar{Λ}$$$_c^-$$ production threshold is cleared. At center-of-mass energies √s = 4574.5 and 4599.5 MeV, the higher statistics data enable us to measure the Λ c polar angle distributions. From these, the Λ c electric over magnetic form factor ratios (|GE/GM|) are measured for the first time. They are found to be 1.14±0.14±0.07 and 1.23±0.05±0.03 respectively, where the first uncertainties are statistical and the second are systematic.« less

  12. Precision Measurement of the e + e - → Λ c + Λ ¯ c - Cross Section Near Threshold

    DOE PAGES

    Ablikim, M.; Achasov, M. N.; Ahmed, S.; ...

    2018-03-29

    The cross section of the e +e - →more » $$Λ_c^+$$$\\bar{Λ}$$$_c^-$$ process is measured with unprecedented precision using data collected with the BESIII detector at √s = 4574.5, 4580.0, 4590.0 and 4599.5 MeV. The non-zero cross section near the $$Λ_c^+$$$\\bar{Λ}$$$_c^-$$ production threshold is cleared. At center-of-mass energies √s = 4574.5 and 4599.5 MeV, the higher statistics data enable us to measure the Λ c polar angle distributions. From these, the Λ c electric over magnetic form factor ratios (|GE/GM|) are measured for the first time. They are found to be 1.14±0.14±0.07 and 1.23±0.05±0.03 respectively, where the first uncertainties are statistical and the second are systematic.« less

  13. Measurement of 208Pb(n ,γ )209Pb Maxwellian averaged neutron capture cross section

    NASA Astrophysics Data System (ADS)

    Weissman, L.; Tessler, M.; Arenshtam, A.; Eliyahu, I.; Halfon, S.; Guerrero, C.; Kaizer, B.; Kijel, D.; Kreisel, A.; Palchan, T.; Paul, M.; Perry, A.; Schimel, G.; Silverman, I.; Shor, A.; Tamim, N.; Vaintraub, S.

    2017-07-01

    The doubly magic 208Pb nucleus is a bottleneck at the termination of the s -process path due to its very low neutron capture cross section. This cross section is also important for the decomposition of s , r processes and U/Th radiogenic decay contributions to the Pb-Bi solar abundances. The 208Pb(n ,γ )209Pb cross section was measured at the Soreq Applied Research Accelerator Facility Phase I using an intense quasi-Maxwellian neutron source produced by irradiation of the liquid-lithium target with a 1.5-mA continuous-wave proton beam at 1.94 MeV. The cross section was measured by counting the β activity from the irradiated lead target. The measurement allowed us to evaluate the Maxwellian averaged cross section (MACS) at 30 keV obtaining a value of 0.33(2) mb. This has been compared with the earlier activation and time-of-flight measurements found in the literature. The MACS cross-sectional value of the 63Cu(n ,γ )64Cu reaction was determined in the same experiment and is compared to a recent published value.

  14. Cross sections for n+{sup 14}N from an R-matrix analysis of the {sup 15}N system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hale, G.M.; Young, P.G.; Chadwick, M.B.

    1994-06-01

    As part of the Hiroshima-Nagasaki Dose Reevaluation Program, a new evaluation of the neutron cross sections for {sup 14}N was made for ENDF/B-VI, based at energies below 2.5 MeV on a multichannel R-matrix analysis of reactions in the {sup 15}N system. The types of data used in the analysis, and the resulting cross sections and resonance structure for {sup 15}N are briefly described. The resonant features of the neutron cross sections were especially well determined by including precise, high-resolution neutron total cross section measurements from ORNL. While the new evaluated cross section appear to be significant improvements over the earliermore » ones, they still need to be tested more extensively against recent measurements of the differential elastic cross section from Oak Ridge.« less

  15. Trojan horse measurement of the 10B(p ,α0)7Be cross section in the energy range from 3 keV to 2.2 MeV

    NASA Astrophysics Data System (ADS)

    Cvetinović, A.; Spitaleri, C.; Spartá, R.; Rapisarda, G. G.; Puglia, S. M. R.; La Cognata, M.; Cherubini, S.; Guardo, G. L.; Gulino, M.; Lamia, L.; Pizzone, R. G.; Romano, S.; Sergi, M. L.; Tumino, A.

    2018-06-01

    The 10B(p ,α0)7Be excitation function has been studied in a wide energy range, from 2.2 MeV down to astrophysical energies, reproducing the cross section above and below the Coulomb barrier in a single experiment. An optimized experimental setup ensured good energy resolution and for the first time a clear separation of α0 and α1 channels of the 10B+2H interaction has been achieved by applying the Trojan Horse method. An improved normalization of the Trojan Horse bare-nucleus astrophysical S (E )-factor to direct data was performed and a value of Ue=391 ±74 eV was obtained for the electron screening potential.

  16. The Trojan Horse Method application on the 10B(p,α0)7Be reaction cross section measurements

    NASA Astrophysics Data System (ADS)

    Cvetinović, A.; Spitaleri, C.; Spartá, R.; Rapisarda, G. G.; Puglia, S. M.; La Cognata, M.; Cherubini, S.; Guardo, G. L.; Gulino, M.; Lamia, L.; Pizzone, R. G.; Romano, S.; Sergi, M. L.

    2018-01-01

    The 10B(p,α0)7Be reaction cross section has been measured in an wide energy range from 2.2 MeV down to 3 keV in a single experiment applying THM. Optimized experimental set-up ensured good energy resolution leading to a good separation of α0 and α1 contributions to the cross section coming from the 7Be ground and first excited state, respectively.

  17. Cross sections for proton-induced reactions on natSb up to 68 MeV

    NASA Astrophysics Data System (ADS)

    Mosby, M. A.; Birnbaum, E. R.; Nortier, F. M.; Engle, J. W.

    2017-12-01

    Nuclear excitation functions for proton induced reactions on antimony targets have been measured up to 68 MeV using stacked foil activation techniques at the Crocker Laboratory of the University of California at Davis. Measurements made are expected to be useful in production of therapeutic radionuclides 119Sb (via production of its parents 119mTe and 119gTe) and 117mSn. This work extends the energy coverage of available data upwards by approximately 30 MeV into a range relevant to medium-energy radionuclide production facilities like the Isotope Production Facility in Los Alamos, New Mexico and the Brookhaven Linear Isotope Producer in Upton, New York.

  18. Effect of wave function on the proton induced L XRP cross sections for 62Sm and 74W

    NASA Astrophysics Data System (ADS)

    Shehla, Kaur, Rajnish; Kumar, Anil; Puri, Sanjiv

    2015-08-01

    The Lk(k= 1, α, β, γ) X-ray production cross sections have been calculated for 74W and 62Sm at different incident proton energies ranging 1-5 MeV using theoretical data sets of different physical parameters, namely, the Li(i=1-3) sub-shell X-ray emission rates based on the Dirac-Fork (DF) model, the fluorescence and Coster Kronig yields based on the Dirac- Hartree-Slater (DHS) model and two sets the proton ionization cross sections based on the DHS model and the ECPSSR in order to assess the influence of the wave function on the XRP cross sections. The calculated cross sections have been compared with the measured cross sections reported in the recent compilation to check the reliability of the calculated values.

  19. Neutron-induced reaction cross-sections of 93Nb with fast neutron based on 9Be(p,n) reaction

    NASA Astrophysics Data System (ADS)

    Naik, H.; Kim, G. N.; Kim, K.; Zaman, M.; Nadeem, M.; Sahid, M.

    2018-02-01

    The cross-sections of the 93Nb (n , 2 n)92mNb, 93Nb (n , 3 n)91mNb and 93Nb (n , 4 n)90Nb reactions with the average neutron energies of 14.4 to 34.0 MeV have been determined by using an activation and off-line γ-ray spectrometric technique. The fast neutrons were produced using the 9Be (p , n) reaction with the proton energies of 25-, 35- and 45-MeV from the MC-50 Cyclotron at the Korea Institute of Radiological and Medical Sciences (KIRAMS). The neutron flux-weighted average cross-sections of the 93Nb(n , xn ; x = 2- 4) reactions were also obtained from the mono-energetic neutron-induced reaction cross-sections of 93Nb calculated using the TALYS 1.8 code, and the neutron flux spectrum based on the MCNPX 2.6.0 code. The present results for the 93Nb(n , xn ; x = 2- 4) reactions are compared with the calculated neutron flux-weighted average values and found to be in good agreement.

  20. First measurement of the muon neutrino charged current single pion production cross section on water with the T2K near detector

    NASA Astrophysics Data System (ADS)

    Abe, K.; Andreopoulos, C.; Antonova, M.; Aoki, S.; Ariga, A.; Assylbekov, S.; Autiero, D.; Ban, S.; Barbi, M.; Barker, G. J.; Barr, G.; Bartet-Friburg, P.; Batkiewicz, M.; Bay, F.; Berardi, V.; Berkman, S.; Bhadra, S.; Bienstock, S.; Blondel, A.; Bolognesi, S.; Bordoni, S.; Boyd, S. B.; Brailsford, D.; Bravar, A.; Bronner, C.; Buizza Avanzini, M.; Calland, R. G.; Campbell, T.; Cao, S.; Caravaca Rodríguez, J.; Cartwright, S. L.; Castillo, R.; Catanesi, M. G.; Cervera, A.; Cherdack, D.; Chikuma, N.; Christodoulou, G.; Clifton, A.; Coleman, J.; Collazuol, G.; Coplowe, D.; Cremonesi, L.; Dabrowska, A.; De Rosa, G.; Dealtry, T.; Denner, P. F.; Dennis, S. R.; Densham, C.; Dewhurst, D.; Di Lodovico, F.; Di Luise, S.; Dolan, S.; Drapier, O.; Duffy, K. E.; Dumarchez, J.; Dytman, S.; Dziewiecki, M.; Emery-Schrenk, S.; Ereditato, A.; Feusels, T.; Finch, A. J.; Fiorentini, G. A.; Friend, M.; Fujii, Y.; Fukuda, D.; Fukuda, Y.; Furmanski, A. P.; Galymov, V.; Garcia, A.; Giffin, S. G.; Giganti, C.; Gilje, K.; Gizzarelli, F.; Gonin, M.; Grant, N.; Hadley, D. R.; Haegel, L.; Haigh, M. D.; Hamilton, P.; Hansen, D.; Harada, J.; Hara, T.; Hartz, M.; Hasegawa, T.; Hastings, N. C.; Hayashino, T.; Hayato, Y.; Helmer, R. L.; Hierholzer, M.; Hillairet, A.; Himmel, A.; Hiraki, T.; Hirota, S.; Hogan, M.; Holeczek, J.; Horikawa, S.; Hosomi, F.; Huang, K.; Ichikawa, A. K.; Ieki, K.; Ikeda, M.; Imber, J.; Insler, J.; Intonti, R. A.; Irvine, T. J.; Ishida, T.; Ishii, T.; Iwai, E.; Iwamoto, K.; Izmaylov, A.; Jacob, A.; Jamieson, B.; Jiang, M.; Johnson, S.; Jo, J. H.; Jonsson, P.; Jung, C. K.; Kabirnezhad, M.; Kaboth, A. C.; Kajita, T.; Kakuno, H.; Kameda, J.; Karlen, D.; Karpikov, I.; Katori, T.; Kearns, E.; Khabibullin, M.; Khotjantsev, A.; Kielczewska, D.; Kikawa, T.; Kim, H.; Kim, J.; King, S.; Kisiel, J.; Knight, A.; Knox, A.; Kobayashi, T.; Koch, L.; Koga, T.; Konaka, A.; Kondo, K.; Kopylov, A.; Kormos, L. L.; Korzenev, A.; Koshio, Y.; Kropp, W.; Kudenko, Y.; Kurjata, R.; Kutter, T.; Lagoda, J.; Lamont, I.; Larkin, E.; Lasorak, P.; Laveder, M.; Lawe, M.; Lazos, M.; Lindner, T.; Liptak, Z. J.; Litchfield, R. P.; Li, X.; Longhin, A.; Lopez, J. P.; Lou, T.; Ludovici, L.; Lu, X.; Magaletti, L.; Mahn, K.; Malek, M.; Manly, S.; Marino, A. D.; Marteau, J.; Martin, J. F.; Martins, P.; Martynenko, S.; Maruyama, T.; Matveev, V.; Mavrokoridis, K.; Ma, W. Y.; Mazzucato, E.; McCarthy, M.; McCauley, N.; McFarland, K. S.; McGrew, C.; Mefodiev, A.; Metelko, C.; Mezzetto, M.; Mijakowski, P.; Miller, C. A.; Minamino, A.; Mineev, O.; Mine, S.; Missert, A.; Miura, M.; Moriyama, S.; Mueller, Th. A.; Murphy, S.; Myslik, J.; Nakadaira, T.; Nakahata, M.; Nakamura, K. G.; Nakamura, K.; Nakamura, K. D.; Nakayama, S.; Nakaya, T.; Nakayoshi, K.; Nantais, C.; Nielsen, C.; Nirkko, M.; Nishikawa, K.; Nishimura, Y.; Novella, P.; Nowak, J.; O'Keeffe, H. M.; Ohta, R.; Okumura, K.; Okusawa, T.; Oryszczak, W.; Oser, S. M.; Ovsyannikova, T.; Owen, R. A.; Oyama, Y.; Palladino, V.; Palomino, J. L.; Paolone, V.; Patel, N. D.; Pavin, M.; Payne, D.; Perkin, J. D.; Petrov, Y.; Pickard, L.; Pickering, L.; Pinzon Guerra, E. S.; Pistillo, C.; Popov, B.; Posiadala-Zezula, M.; Poutissou, J.-M.; Poutissou, R.; Przewlocki, P.; Quilain, B.; Radermacher, T.; Radicioni, E.; Ratoff, P. N.; Ravonel, M.; Rayner, M. A. M.; Redij, A.; Reinherz-Aronis, E.; Riccio, C.; Rojas, P.; Rondio, E.; Roth, S.; Rubbia, A.; Rychter, A.; Sacco, R.; Sakashita, K.; Sánchez, F.; Sato, F.; Scantamburlo, E.; Scholberg, K.; Schoppmann, S.; Schwehr, J.; Scott, M.; Seiya, Y.; Sekiguchi, T.; Sekiya, H.; Sgalaberna, D.; Shah, R.; Shaikhiev, A.; Shaker, F.; Shaw, D.; Shiozawa, M.; Shirahige, T.; Short, S.; Smy, M.; Sobczyk, J. T.; Sobel, H.; Sorel, M.; Southwell, L.; Stamoulis, P.; Steinmann, J.; Stewart, T.; Stowell, P.; Suda, Y.; Suvorov, S.; Suzuki, A.; Suzuki, K.; Suzuki, S. Y.; Suzuki, Y.; Tacik, R.; Tada, M.; Takahashi, S.; Takeda, A.; Takeuchi, Y.; Tanaka, H. K.; Tanaka, H. A.; Terhorst, D.; Terri, R.; Thakore, T.; Thompson, L. F.; Tobayama, S.; Toki, W.; Tomura, T.; Touramanis, C.; Tsukamoto, T.; Tzanov, M.; Uchida, Y.; Vacheret, A.; Vagins, M.; Vallari, Z.; Vasseur, G.; Wachala, T.; Wakamatsu, K.; Walter, C. W.; Wark, D.; Warzycha, W.; Wascko, M. O.; Weber, A.; Wendell, R.; Wilkes, R. J.; Wilking, M. J.; Wilkinson, C.; Wilson, J. R.; Wilson, R. J.; Yamada, Y.; Yamamoto, K.; Yamamoto, M.; Yanagisawa, C.; Yano, T.; Yen, S.; Yershov, N.; Yokoyama, M.; Yoo, J.; Yoshida, K.; Yuan, T.; Yu, M.; Zalewska, A.; Zalipska, J.; Zambelli, L.; Zaremba, K.; Ziembicki, M.; Zimmerman, E. D.; Zito, M.; Żmuda, J.; T2K Collaboration

    2017-01-01

    The T2K off-axis near detector, ND280, is used to make the first differential cross section measurements of muon neutrino charged current single positive pion production on a water target at energies ˜0.8 GeV . The differential measurements are presented as a function of the muon and pion kinematics, in the restricted phase space defined by pπ+>200 MeV /c , pμ>200 MeV /c , cos (θπ+) >0.3 and cos (θμ) >0.3 . The total flux integrated νμ charged current single positive pion production cross section on water in the restricted phase space is measured to be ⟨σ ⟩ϕ =4.25 ±0.48 (stat )±1.56 (syst )×10-40 cm2/nucleon . The total cross section is consistent with the NEUT prediction (5.03 ×10-40 cm2/nucleon ) and 2 σ lower than the GENIE prediction (7.68 ×10-40 cm2/nucleon ). The differential cross sections are in good agreement with the NEUT generator. The GENIE simulation reproduces well the shapes of the distributions, but overestimates the overall cross section normalization.

  1. Evaluated activation cross sections of longer-lived radionuclides produced by deuteron induced reactions on natural nickel

    NASA Astrophysics Data System (ADS)

    Takács, S.; Tárkányi, F.; Király, B.; Hermanne, A.; Sonck, M.

    2007-07-01

    Activation cross sections for deuteron induced nuclear reactions on natural nickel target were studied by using a standard stacked foil technique and gamma spectrometry up to 50 MeV deuteron bombarding energy. Reaction products with half life of at least half an hour were studied. Experimental elemental activation cross sections were determined for reactions on nickel resulting in 61,64Cu, 56,57Ni, 55,56,57,58,60,61Co, 52,54,56Mn and 51Cr radionuclides and were compared with earlier measured data.

  2. Accurate measurements of the 63Cu(d,p)64Cu and natCu(d,x)65Zn cross-sections in the 2.77-5.62 MeV energy range

    NASA Astrophysics Data System (ADS)

    Weissman, L.; Kreisel, A.; Hirsh, T.; Aviv, O.; Berkovits, D.; Girshevitz, O.; Eisen, Y.

    2015-01-01

    The cross sections of 63Cu(d,p)64Cu and natCu(d,x)65Zn were determined for deuteron beam energy range of 2.77-5.62 MeV at the SARAF Phase I variable energy LINAC. Thin copper foils were irradiated by a deuteron beam followed up by measurement of the produced activation at the Soreq NRC low-background γ-counting system. The results are consistent with data in the literature, but are of better accuracy. The data are important for assessment of the activation of components of Radio Frequency Quadrupole injectors and Medium Energy Beam Transport beam dumps in modern deuteron LINACs.

  3. Precision Measurement of the e + e − → Λ c + Λ ¯ c − Cross Section Near Threshold

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ablikim, M.; Achasov, M. N.; Ahmed, S.

    2018-03-01

    The cross section of the e+e− ! +c¯ −c process is measured with unprecedented precision using data collected with the BESIII detector at ps = 4574.5, 4580.0, 4590.0 and 4599.5 MeV. The non-zero cross section near the +c¯ −c production threshold is cleared. At center-of-mass energies ps = 4574.5 and 4599.5 MeV, the higher statistics data enable us to measure the c polar angle distributions. From these, the c electric over magnetic form factor ratios (|GE/GM|) are measured for the first time. They are found to be 1.14±0.14±0.07 and 1.23±0.05±0.03 respectively, where the first uncertainties are statistical and the secondmore » are systematic.« less

  4. M-shell electron capture and direct ionization of gold by 25-MeV carbon and 32-MeV oxygen ions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Andrews, M.C.; McDaniel, F.D.; Duggan, J.L.

    1984-01-01

    M-shell x-ray production cross sections have been measured for thin solid targets of Au for 25 MeV /sup 12/C/sup q+/ (q = 4, 5, 6) and for 32 MeV /sup 16/O/sup q+/ (q = 5, 7, 8). The microscopic cross sections were determined from measurements made with targets ranging in thickness from 0.5 to 100 ..mu..g/cm/sup 2/. For projectiles with one or two K-shell vacancies, the M-shell x-ray production cross sections are found to be enhanced over those by projectiles without a K-shell vacancy. The sum of direct ionization to the continuum (DI) and electron capture (EC) to the L,more » M, N ... shells and EC to the K-shell of the projectile have been extracted from the data. The results are compared to the predictions of first Born theories i.e. PWBA for DI and OBK of Nikolaev for EC and the ECPSSR approach that accounts for energy loss, Coulomb deflection and relativistic effects in the perturbed stationary state theory. 25 references, 3 figures, 1 table.« less

  5. Measurement of the neutrino neutral-current elastic differential cross section on mineral oil at Eν˜1GeV

    NASA Astrophysics Data System (ADS)

    Aguilar-Arevalo, A. A.; Anderson, C. E.; Bazarko, A. O.; Brice, S. J.; Brown, B. C.; Bugel, L.; Cao, J.; Coney, L.; Conrad, J. M.; Cox, D. C.; Curioni, A.; Dharmapalan, R.; Djurcic, Z.; Finley, D. A.; Fleming, B. T.; Ford, R.; Garcia, F. G.; Garvey, G. T.; Grange, J.; Green, C.; Green, J. A.; Hart, T. L.; Hawker, E.; Imlay, R.; Johnson, R. A.; Karagiorgi, G.; Kasper, P.; Katori, T.; Kobilarcik, T.; Kourbanis, I.; Koutsoliotas, S.; Laird, E. M.; Linden, S. K.; Link, J. M.; Liu, Y.; Liu, Y.; Louis, W. C.; Mahn, K. B. M.; Marsh, W.; Mauger, C.; McGary, V. T.; McGregor, G.; Metcalf, W.; Meyers, P. D.; Mills, F.; Mills, G. B.; Monroe, J.; Moore, C. D.; Mousseau, J.; Nelson, R. H.; Nienaber, P.; Nowak, J. A.; Osmanov, B.; Ouedraogo, S.; Patterson, R. B.; Pavlovic, Z.; Perevalov, D.; Polly, C. C.; Prebys, E.; Raaf, J. L.; Ray, H.; Roe, B. P.; Russell, A. D.; Sandberg, V.; Schirato, R.; Schmitz, D.; Shaevitz, M. H.; Shoemaker, F. C.; Smith, D.; Soderberg, M.; Sorel, M.; Spentzouris, P.; Spitz, J.; Stancu, I.; Stefanski, R. J.; Sung, M.; Tanaka, H. A.; Tayloe, R.; Tzanov, M.; van de Water, R. G.; Wascko, M. O.; White, D. H.; Wilking, M. J.; Yang, H. J.; Zeller, G. P.; Zimmerman, E. D.

    2010-11-01

    We report a measurement of the flux-averaged neutral-current elastic differential cross section for neutrinos scattering on mineral oil (CH2) as a function of four-momentum transferred squared, Q2. It is obtained by measuring the kinematics of recoiling nucleons with kinetic energy greater than 50 MeV which are readily detected in MiniBooNE. This differential cross-section distribution is fit with fixed nucleon form factors apart from an axial mass MA that provides a best fit for MA=1.39±0.11GeV. Using the data from the charged-current neutrino interaction sample, a ratio of neutral-current to charged-current quasielastic cross sections as a function of Q2 has been measured. Additionally, single protons with kinetic energies above 350 MeV can be distinguished from neutrons and multiple nucleon events. Using this marker, the strange quark contribution to the neutral-current axial vector form factor at Q2=0, Δs, is found to be Δs=0.08±0.26.

  6. Observation of a cross-section enhancement near mass threshold in e+e-→Λ Λ ¯

    NASA Astrophysics Data System (ADS)

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

    2018-02-01

    The process e+e-→Λ Λ ¯ is studied using data samples at √{s }=2.2324 , 2.400, 2.800 and 3.080 GeV collected with the BESIII detector operating at the BEPCII collider. The Born cross section is measured at √{s }=2.2324 GeV , which is 1.0 MeV above the Λ Λ ¯ mass threshold, to be 305 ±4 5-36+66 pb , where the first uncertainty is statistical and the second systematic. The cross section near threshold is larger than that expected from theory, which predicts the cross section to vanish at threshold. The Born cross sections at √{s }=2.400 , 2.800 and 3.080 GeV are measured and found to be consistent with previous experimental results, but with improved precision. Finally, the corresponding effective electromagnetic form factors of Λ are deduced.

  7. 56Fe capture cross section experiments at the RPI LINAC Center

    NASA Astrophysics Data System (ADS)

    McDermott, Brian; Blain, Ezekiel; Thompson, Nicholas; Weltz, Adam; Youmans, Amanda; Danon, Yaron; Barry, Devin; Block, Robert; Daskalakis, Adam; Epping, Brian; Leinweber, Gregory; Rapp, Michael

    2017-09-01

    A new array of C6D6 detectors installed at the RPI LINAC Center has enabled the capability to measure neutron capture cross sections above the 847 keV inelastic scattering threshold of 56Fe through the use of digital post-processing filters and pulse-integral discriminators, without sacrificing the statistical quality of data at lower incident neutron energies where such filtering is unnecessary. The C6D6 detectors were used to perform time-of-flight capture cross section measurements on a sample 99.87% enriched iron-56. The total-energy method, combined with the pulse height weighting technique, were then applied to the raw data to determine the energy-dependent capture yield. Above the inelastic threshold, the data were analyzed with a pulse-integral filter to reveal the capture signal, extending the the full data set to 2 MeV.

  8. Experimental differential cross sections, level densities, and spin cutoffs as a testing ground for nuclear reaction codes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Voinov, Alexander V.; Grimes, Steven M.; Brune, Carl R.

    Proton double-differential cross sections from 59Co(α,p) 62Ni, 57Fe(α,p) 60Co, 56Fe( 7Li,p) 62Ni, and 55Mn( 6Li,p) 60Co reactions have been measured with 21-MeV α and 15-MeV lithium beams. Cross sections have been compared against calculations with the empire reaction code. Different input level density models have been tested. It was found that the Gilbert and Cameron [A. Gilbert and A. G. W. Cameron, Can. J. Phys. 43, 1446 (1965)] level density model is best to reproduce experimental data. Level densities and spin cutoff parameters for 62Ni and 60Co above the excitation energy range of discrete levels (in continuum) have been obtainedmore » with a Monte Carlo technique. Furthermore, excitation energy dependencies were found to be inconsistent with the Fermi-gas model.« less

  9. Neutron Scattering Cross Section Measurements for 169Tm via the (n,n') Technique

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Alimeti, Afrim; Kegel, Gunter H.R.; Egan, James J.

    2005-05-24

    The neutron physics group at the University of Massachusetts Lowell (UML) has been involved in a program of scattering cross-section measurements for highly deformed nuclei such as 159Tb, 169Tm, 232Th, 235U, 238U, and 239Pu. Ko et al. have reported neutron inelastic scattering data from 169Tm for states above 100 keV via the (n,n'{gamma}) reaction at incident energies in the 0.2 MeV to 1.0 MeV range. In the present research, in which the time-of-flight method was employed, direct (n,n') measurements of neutrons scattered from 169Tm in the 0.2 to 1.0 MeV range were taken. It requires that our 5.5-MeV Van demore » Graaff accelerator be operated in the pulsed and bunched beam mode producing subnanosecond pulses at a 5-MHz repetition frequency. Neutrons are produced by the 7Li(p,n)7Be reaction using a thin metallic elemental lithium target.« less

  10. Measurement of Continuous-Energy Neutron-Incident Neutron-Production Cross Section

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shigyo, Nobuhiro; Kunieda, Satoshi; Watanabe, Takehito

    Continuous energy neutron-incident neutron-production double differential cross sections were measured at the Weapons Neutron Research (WNR) facility of the Los Alamos Neutron Science Center. The energy of emitted neutrons was derived from the energy deposition in a detector. The incident-neutron energy was obtained by the time-of-flight method between the spallation target of WNR and the emitted neutron detector. Two types of detectors were adopted to measure the wide energy range of neutrons. The liquid organic scintillators covered up to 100 MeV. The recoil proton detectors that constitute the recoil proton radiator and phoswich type NaI (Tl) scintillators were used formore » neutrons above several tens of MeV. Iron and lead were used as sample materials. The experimental data were compared with the evaluated nuclear data, the results of GNASH, JQMD, and PHITS codes.« less

  11. Inelastic neutron scattering cross-section measurements on 7Li and 63,65Cu

    NASA Astrophysics Data System (ADS)

    Nyman, Markus; Belloni, Francesca; Ichinkhorloo, Dagvadorj; Pirovano, Elisa; Plompen, Arjan; Rouki, Chariklia

    2017-09-01

    The γ-ray production cross section for the 477.6-keV transition in 7Li following inelastic neutron scattering has been measured from the reaction threshold up to 18 MeV. This cross section is interesting as a possible standard for other inelastic scattering measurements. The experiment was conducted at the Geel Electron LINear Accelerator (GELINA) pulsed white neutron source with the Gamma Array for Inelastic Neutron Scattering (GAINS) spectrometer. Previous measurements of this cross section are reviewed and compared with our results. Recently, this cross section has also been calculated using the continuum discretized coupled-channels (CDCC) method. Experiments for studying neutrinoless double-β decay (2β0ν) or other very rare processes require greatly reducing the background radiation level (both intrinsic and external). Copper is a common shielding and structural material, used extensively in experiments such as COBRA, CUORE, EXO, GERDA, and MAJORANA. Understanding the background contribution arising from neutron interactions in Cu is important when searching for very weak experimental signals. Neutron inelastic scattering on natCu was investigated with GAINS. The results are compared with previous experimental data and evaluated nuclear data libraries.

  12. Neutron-Induced Fission Cross Section Measurements for Full Suite of Uranium Isotopes

    NASA Astrophysics Data System (ADS)

    Laptev, Alexander; Tovesson, Fredrik; Hill, Tony

    2010-11-01

    A well established program of neutron-induced fission cross section measurement at Los Alamos Neutron Science Center (LANSCE) is supporting the Fuel Cycle Research program (FC R&D). The incident neutron energy range spans energies from sub-thermal energies up to 200 MeV by measuring both the Lujan Center and the Weapons Neutron Research center (WNR). Conventional parallel-plate fission ionization chambers with actinide deposited foils are used as a fission detector. The time-of-flight method is implemented to measure neutron energy. Counting rate ratio from investigated and standard U-235 foils is translated into fission cross section ratio. Different methods of normalization for measured ratio are employed, namely, using of actinide deposit thicknesses, normalization to evaluated data, etc. Finally, ratios are converted to cross sections based on the standard U-235 fission cross section data file. Preliminary data for newly investigated isotopes U-236 and U-234 will be reported. Those new data complete a full suite of Uranium isotopes, which were investigated with presented experimental approach. When analysis of the new measured data will is completed, data will be delivered to evaluators. Having data for full set of Uranium isotopes will increase theoretical modeling capabilities and make new data evaluations much more reliable.

  13. 16O(n,α) cross section investigation using LENZ instrument at LANSCE

    NASA Astrophysics Data System (ADS)

    Lee, H. Y.; Mosby, S.; Haight, R. C.; White, M. C.

    2016-06-01

    Importance of studying the 16O(n,α) reaction is motivated by multiple nuclear applications. The Los Alamos Neutron Science Center (LANSCE) produces a white neutron spectrum ranging from thermal to several hundreds of MeV energies. We have recently developed the LENZ (Low Energy NZ-neutron induced charged particle detection) capability to measure high-precision (n,α) cross sections. In order to provide more reliable data, we have enhanced solid angle coverage, and improved signal-to-noise ratios and time-of-flight resolution by implementing digitizer waveform analysis. The LENZ was commissioned by studying the 59Co(n,α) reaction with neutron beams in early 2015. For the 16O(n,α) reaction, we investigate solid oxygen targets and make a relative measurement to a better known cross section, such as the 6Li(n,α) reaction in order to further reduce systematic uncertainty. We will discuss the progress of the 16O(n,α) study at LANSCE and the outlook for improving Hauser-Feshbah prediction on (n,p) reaction cross sections.

  14. Elastic and Inelastic Scattering of 27.6 Mev Deuterons in Ni. Report No. 55; DISPERSION ELASTICA E INELASTICA DE DEUTERONES DE 27,6 Mev POR Ni. INFORME NO. 55

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mayo, S.; Rosenblatt, J.

    1961-01-01

    Elastic and inelastic differential cross sections in Ni(d,d)Ni with 27.6 Mev deuterons were measured with the aid of scintillation technique. Charged particle spectra from the reaction were observed at laboratory angles of 15 up to 150 degrees, showing the presence of Q-positive stripping protons and elastic and inelastic deuteron groups. Due to isotopic mixture in natural Ni and the rather high level density above 2 Mev of excitation in most of those isotopes, only inelastic deuteron groups going to the first excited states in Ni/sup 58/ and Ni/ sup 60/ could be identified. Elastic angular distribution exhibits similarities to thatmore » obtained by Yntema at 21.6 Mev, showing the typical diffraction patterns. At backward angles, a slight growing in the crosssection was observed which was not observed at 21.6 Mev. By regarding the elastic scattering like a classical light diffraction by a black disk, an interaction radius of 6.8 plus or minus 0.8 f was derived. Inelastic angular distributions were fitted by semiclassical Butler et al. theory and Huby-Newns theory. Due to above-mentioned limitations level mixtures could not be avoided; however, a group of deuterons going to Ni/ sup 58/ 1.45 Mev, probably mixed with Ni/sup 60/ 1.33 Mev, could be identified as proceeding via direct interaction with l = 2 and interaction radius 6.7 f and 6.9 f, respectively. Another inelastic group identified as Ni/sup 58/ 2.46 Mev mixed with Ni/sup 60/ 2.50 Mev is well fitted by l = 2 plus l = 4 and interaction radius 8.9 f and 8.7 f respectively, showing direct interaction behavor. Contributions to the above processes from compound nucleus formation are small as can be seen from absolute cross sections above 50 degrees. Total cross section for the formation of compound nucleus is about 860 mbarn. According to selection rules for deuteron scattering, 2/sup +/ is assigned to levels 1.45 Mev and 2.46 Mev in Ni/sup 58/; however this assignment is not definitive due to background from

  15. Cross Sections for the Production of Cosmogenic Nuclides with Protons up to 400 MeV for the Interpretation of Cosmic-Ray-produced Nuclides

    NASA Astrophysics Data System (ADS)

    Schiekel, Th.; Rosel, R.; Herpers, U.; Bodemann, R.; Leya, I.; Gloris, M.; Michel, R.; Dittrich, B.; Kubik, P.; Suter, M.

    1993-07-01

    Integral excitation functions of the cosmogenic nuclides are the basic requirement for the interpretation of interactions between cosmic ray particles and extraterrestrial and terrestrial matter. Together with the knowledge of primary and secondary particle fields inside an irradiated body, model calculations can be developed to interpret abundances of cosmogenic nuclides in dependencies of the irradiation history of the irradiated body and of the cosmic particle ray itself. The quality of those model calculations depends on the quality of the available cross-section database, which is neither comprehensive nor reliable for the most important nuclides like the long-lived radionuclides (i.e., 10Be, 26Al, 36Cl, 41Ca) and the stable rare gas isotopes. For a systematic investigation in this field of science we carried out several irradiation experiments with protons in the energy region between 45 MeV and 400 MeV at the Paul Scherrer Institut (Villigen, Switzerland) and the Laboratoire Nationale Saturne (Saclay, France) using the stacked foil technique. We included 21 different target elements with Z between 6 and 79 (C, N as Si3N4, O as SiO2, Mg, Al, Si, Ca as CaC2H2O4, Ti, V, Mn as Mn/Ni alloy, Fe, Co, Ni, Cu, Sr as SrF2, Y, Zr, Nb, Rh, Ba as Ba containing glass and Au) in our experiments. The proton fluxes were monitored via the reaction 27Al(p,3p3n)22Na using the evaluated data of [1]. Residual nuclides were measured by X-, gamma-, and after a chemical separation by accelerator mass spectrometry. In order to check the quality of our experimental procedures we included some target elements in our new experiments for which consistent excitation functions have already been determined [2,3,4]. Our new data show excellent agreement with the earlier measurements. We measured cross sections for more than 120 different reactions. Here we report on the results for target elements with Z up to 28. The exsisting database of experimental excitation functions for the production

  16. Theoretical and Experimental K+ + Nucleus Total and Reaction Cross Sections from the KDP-RIA Model

    NASA Astrophysics Data System (ADS)

    Kerr, L. K.; Clark, B. C.; Hama, S.; Ray, L.; Hoffmann, G. W.

    2000-02-01

    The 5-dimensional spin-0 form of the Kemmer-Duffin-Petiau (KDP) equation is used to calculate scattering observables [elastic differential cross sections (dσ / dΩ), total cross sections (σ Tot ), and total reaction cross sections (σ Reac )] and to deduce σ Tot and σReac from transmission data for K+ + 6Li, 12C, 28Si and 40Ca at several momenta in the range 488 - 714 MeV / c. Realistic uncertainties are generated for the theoretical predictions. These errors, mainly due to uncertainties associated with the elementary K+ + nucleon amplitudes, are large, which may account for some of the disagreement between experimental and theoretical σTot and σReac. The results suggest that the K+ + nucleon amplitudes need to be much better determined before further improvement in the understanding of these data can occur.

  17. α -induced reactions on 115In: Cross section measurements and statistical model analysis

    NASA Astrophysics Data System (ADS)

    Kiss, G. G.; Szücs, T.; Mohr, P.; Török, Zs.; Huszánk, R.; Gyürky, Gy.; Fülöp, Zs.

    2018-05-01

    Background: α -nucleus optical potentials are basic ingredients of statistical model calculations used in nucleosynthesis simulations. While the nucleon+nucleus optical potential is fairly well known, for the α +nucleus optical potential several different parameter sets exist and large deviations, reaching sometimes even an order of magnitude, are found between the cross section predictions calculated using different parameter sets. Purpose: A measurement of the radiative α -capture and the α -induced reaction cross sections on the nucleus 115In at low energies allows a stringent test of statistical model predictions. Since experimental data are scarce in this mass region, this measurement can be an important input to test the global applicability of α +nucleus optical model potentials and further ingredients of the statistical model. Methods: The reaction cross sections were measured by means of the activation method. The produced activities were determined by off-line detection of the γ rays and characteristic x rays emitted during the electron capture decay of the produced Sb isotopes. The 115In(α ,γ )119Sb and 115In(α ,n )Sb118m reaction cross sections were measured between Ec .m .=8.83 and 15.58 MeV, and the 115In(α ,n )Sb118g reaction was studied between Ec .m .=11.10 and 15.58 MeV. The theoretical analysis was performed within the statistical model. Results: The simultaneous measurement of the (α ,γ ) and (α ,n ) cross sections allowed us to determine a best-fit combination of all parameters for the statistical model. The α +nucleus optical potential is identified as the most important input for the statistical model. The best fit is obtained for the new Atomki-V1 potential, and good reproduction of the experimental data is also achieved for the first version of the Demetriou potentials and the simple McFadden-Satchler potential. The nucleon optical potential, the γ -ray strength function, and the level density parametrization are also

  18. Evaluation of proton cross-sections for radiation sources in the proton accelerator

    NASA Astrophysics Data System (ADS)

    Cho, Young-Sik; Lee, Cheol-Woo; Lee, Young-Ouk

    2007-08-01

    Proton Engineering Frontier Project (PEFP) is currently building a proton accelerator in Korea which consists of a proton linear accelerator with 100 MeV of energy, 20 mA of current and various particle beam facilities. The final goal of this project consists of the production of 1 GeV proton beams, which will be used for various medical and industrial applications as well as for research in basic and applied sciences. Carbon and copper in the proton accelerator for PEPP, through activation, become radionuclides such as 7Be and 64Cu. Copper is a major element of the accelerator components and the carbon is planned to be used as a target material of the beam dump. A recent survey showed that the currently available cross-sections create a large difference from the experimental data in the production of some residual nuclides by the proton-induced reactions for carbon and copper. To more accurately estimate the production of radioactive nuclides in the accelerator, proton cross-sections for carbon and copper are evaluated. The TALYS code was used for the evaluation of the cross-sections for the proton-induced reactions. To obtain the cross-sections which best fits the experimental data, optical model parameters for the neutron, proton and other complex particles such as the deuteron and alpha were successively adjusted. The evaluated cross-sections in this study are compared with the measurements and other evaluations .

  19. Observation of a cross-section enhancement near mass threshold in e + e - → Λ Λ ¯

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ablikim, M.; Achasov, M. N.; Ahmed, S.

    Tmore » he process e + e - → Λ Λ ¯ is studied using data samples at √s = 2.2324, 2.400, 2.800 and 3.080 GeV collected with the BESIII detector operating at the BEPCII collider. he Born cross section is measured at √s=2.2324 GeV, which is 1.0 MeV above the Λ Λ ¯ mass threshold, to be 305±$$45_{-36}^{+66}$$ pb, where the first uncertainty is statistical and the second systematic. he substantial cross section near threshold is significantly larger than that expected from theory, which predicts the cross section to vanish at threshold. he Born cross sections at √s=2.400, 2.800 and 3.080 GeV are measured and found to be consistent with previous experimental results, but with improved precision. Finally, the corresponding effective electromagnetic form factors of Λ are deduced.« less

  20. Observation of a cross-section enhancement near mass threshold in e + e - → Λ Λ ¯

    DOE PAGES

    Ablikim, M.; Achasov, M. N.; Ahmed, S.; ...

    2018-02-28

    Tmore » he process e + e - → Λ Λ ¯ is studied using data samples at √s = 2.2324, 2.400, 2.800 and 3.080 GeV collected with the BESIII detector operating at the BEPCII collider. he Born cross section is measured at √s=2.2324 GeV, which is 1.0 MeV above the Λ Λ ¯ mass threshold, to be 305±$$45_{-36}^{+66}$$ pb, where the first uncertainty is statistical and the second systematic. he substantial cross section near threshold is significantly larger than that expected from theory, which predicts the cross section to vanish at threshold. he Born cross sections at √s=2.400, 2.800 and 3.080 GeV are measured and found to be consistent with previous experimental results, but with improved precision. Finally, the corresponding effective electromagnetic form factors of Λ are deduced.« less

  1. Closed-form expressions for state-to-state charge-transfer differential cross sections in a modified Faddeev three-body approach

    NASA Astrophysics Data System (ADS)

    Adivi, E. Ghanbari; Brunger, M. J.; Bolorizadeh, M. A.; Campbell, L.

    2007-02-01

    The second-order Faddeev-Watson-Lovelace approximation in a modified form is applied to charge transfer from hydrogenlike target atoms by a fully stripped energetic projectile ion. The state-to-state, nlm→n'l'm' , partial transition amplitudes are calculated analytically. The method is specifically applied to the collision of protons with hydrogen atoms, where differential cross sections of different transitions are calculated for incident energies of 2.8 and 5.0MeV . It is shown that the Thomas peak is present in all transition cross sections. The partial cross sections are then summed and compared with the available forward-angle experimental data, showing good agreement.

  2. Investigation of the 68Zn(p, 2p) 67Cu nuclear reaction: New measurements up to 40 MeV and compilation up to 100 MeV

    NASA Astrophysics Data System (ADS)

    Szelecsényi, F.; Steyn, G. F.; Dolley, S. G.; Kovács, Z.; Vermeulen, C.; van der Walt, T. N.

    2009-06-01

    The excitation function was measured for the 68Zn(p, 2p) 67Cu nuclear reaction from its threshold energy up to 40 MeV. Nine pieces of highly enriched 68Zn (>98%) metal foils were irradiated to obtain reliable cross-sections using the usual stacked-foil technique. All foils were subjected to high efficiency radiochemical separation before the activity measurements. A critical compilation of the available experimental cross-section results was also performed. Thick target yields of 67Cu and the longer-lived copper radio-contaminants ( 61Cu and 64Cu) were calculated using the reliable literature results up to 100 MeV. Additionally, EOB (End Of Bombardment) contamination levels as a function of bombarding energy and irradiation time were deduced.

  3. Direct measurement of the 7Be(n, α)4 He reaction cross sections for the cosmological Li problem

    NASA Astrophysics Data System (ADS)

    Kawabata, Takahiro; Fujikawa, Yuki; Furuno, Tatsuya; Goto, Tatsuya; Hashimoto, Toshikazu; Ichikawa, Masaya; Itoh, Makoto; Iwasa, Naohito; Kanada-En'yo, Yoshiko; Koshikawa, Ami; Kubono, Shigeru; Miyawaki, Eisuke; Mizuno, Masatoshi; Mizutani, Keigo; Morimoto, Takahiro; Murata, Motoki; Nanamura, Takuya; Nishimura, Shunji; Nanamura, Takuya; Okamoto, Shintaro; Sakaguchi, Yuichi; Sakata, Itsushi; Sakaue, Akane; Sawada, Ryo; Shikata, Yuki; Takahashi, Yu; Takechi, Daiki; Takeda, Tomoya; Takimoto, Chisato; Tsumura, Miho; Watanabe, Ken; Yoshida, Sota

    2017-11-01

    The cross sections of the 7Be(n, α)4He reaction for p-wave neutrons were experimentally determined at Ec.m. = 0.20-0.81 MeV close to the Big Bang nucleosynthesis (BBN) energy window for the first time on the basis of the detailed balance principle by measuring the time-reverse reaction. The obtained cross sections are much larger than the cross sections for s-wave neutrons inferred from the recent measurement at the n_TOF facility in CERN, but significantly smaller than the theoretical estimation widely used in the BBN calculations. The present results suggest the 7Be(n, α)4 He reaction rate is not large enough to solve the cosmological lithium problem

  4. Neutron capture cross section measurement of 151Sm at the CERN neutron time of flight facility (n_TOF).

    PubMed

    Abbondanno, U; Aerts, G; Alvarez-Velarde, F; Alvarez-Pol, H; Andriamonje, S; Andrzejewski, J; Badurek, G; Baumann, P; Becvár, F; Benlliure, J; Berthoumieux, E; Calviño, F; Cano-Ott, D; Capote, R; Cennini, P; Chepel, V; Chiaveri, E; Colonna, N; Cortes, G; Cortina, D; Couture, A; Cox, J; Dababneh, S; Dahlfors, M; David, S; Dolfini, R; Domingo-Pardo, C; Duran, I; Embid-Segura, M; Ferrant, L; Ferrari, A; Ferreira-Marques, R; Frais-Koelbl, H; Furman, W; Goncalves, I; Gallino, R; Gonzalez-Romero, E; Goverdovski, A; Gramegna, F; Griesmayer, E; Gunsing, F; Haas, B; Haight, R; Heil, M; Herrera-Martinez, A; Isaev, S; Jericha, E; Käppeler, F; Kadi, Y; Karadimos, D; Kerveno, M; Ketlerov, V; Koehler, P; Konovalov, V; Krticka, M; Lamboudis, C; Leeb, H; Lindote, A; Lopes, I; Lozano, M; Lukic, S; Marganiec, J; Marrone, S; Martinez-Val, J; Mastinu, P; Mengoni, A; Milazzo, P M; Molina-Coballes, A; Moreau, C; Mosconi, M; Neves, F; Oberhummer, H; O'Brien, S; Pancin, J; Papaevangelou, T; Paradela, C; Pavlik, A; Pavlopoulos, P; Perlado, J M; Perrot, L; Pignatari, M; Plag, R; Plompen, A; Plukis, A; Poch, A; Policarpo, A; Pretel, C; Quesada, J; Raman, S; Rapp, W; Rauscher, T; Reifarth, R; Rosetti, M; Rubbia, C; Rudolf, G; Rullhusen, P; Salgado, J; Soares, J C; Stephan, C; Tagliente, G; Tain, J; Tassan-Got, L; Tavora, L; Terlizzi, R; Vannini, G; Vaz, P; Ventura, A; Villamarin, D; Vincente, M C; Vlachoudis, V; Voss, F; Wendler, H; Wiescher, M; Wisshak, K

    2004-10-15

    The151Sm(n,gamma)152Sm cross section has been measured at the spallation neutron facility n_TOF at CERN in the energy range from 1 eV to 1 MeV. The new facility combines excellent resolution in neutron time-of-flight, low repetition rates, and an unsurpassed instantaneous luminosity, resulting in rather favorable signal/background ratios. The 151Sm cross section is of importance for characterizing neutron capture nucleosynthesis in asymptotic giant branch stars. At a thermal energy of kT=30 keV the Maxwellian averaged cross section of this unstable isotope (t(1/2)=93 yr) was determined to be 3100+/-160 mb, significantly larger than theoretical predictions.

  5. Rapidity gap cross sections measured with the ATLAS detector in pp collisions at $$\\sqrt{s} = 7 \\mbox{~TeV}$$

    DOE PAGES

    Aad, G.; Abbott, B.; Abdallah, J.; ...

    2012-03-13

    Pseudorapidity gap distributions in proton-proton collisions at s√=7 ~TeVs=7 ~TeV are studied using a minimum bias data sample with an integrated luminosity of 7.1 μb -1. Cross sections are measured differentially in terms of Δη F, the larger of the pseudorapidity regions extending to the limits of the ATLAS sensitivity, at η= ±4.9, in which no final state particles are produced above a transverse momentum threshold pmore » $$cut\\atop{T}$$ . The measurements span the region 0F < 8 for 200~MeV< p$$cut\\atop{T}$$ <800~MeV200~MeVF, the data test the reliability of hadronisation models in describing rapidity and transverse momentum fluctuations in final state particle production. The measurements at larger gap sizes are dominated by contributions from the single diffractive dissociation process (pp→Xp), enhanced by double dissociation (pp→XY) where the invariant mass of the lighter of the two dissociation systems satisfies M Y≲7 GeV. The resulting cross section is dσ/dΔη F≈1 mb for Δη F≳3. The large rapidity gap data are used to constrain the value of the Pomeron intercept appropriate to triple Regge models of soft diffraction. Finally, the cross section integrated over all gap sizes is compared with other LHC inelastic cross section measurements.« less

  6. Evaporation residue cross-section measurements for 48Ti-induced reactions

    NASA Astrophysics Data System (ADS)

    Sharma, Priya; Behera, B. R.; Mahajan, Ruchi; Thakur, Meenu; Kaur, Gurpreet; Kapoor, Kushal; Rani, Kavita; Madhavan, N.; Nath, S.; Gehlot, J.; Dubey, R.; Mazumdar, I.; Patel, S. M.; Dhibar, M.; Hosamani, M. M.; Khushboo, Kumar, Neeraj; Shamlath, A.; Mohanto, G.; Pal, Santanu

    2017-09-01

    Background: A significant research effort is currently aimed at understanding the synthesis of heavy elements. For this purpose, heavy ion induced fusion reactions are used and various experimental observations have indicated the influence of shell and deformation effects in the compound nucleus (CN) formation. There is a need to understand these two effects. Purpose: To investigate the effect of proton shell closure and deformation through the comparison of evaporation residue (ER) cross sections for the systems involving heavy compound nuclei around the ZCN=82 region. Methods: A systematic study of ER cross-section measurements was carried out for the 48Ti+Nd,150142 , 144Sm systems in the energy range of 140 -205 MeV . The measurement has been performed using the gas-filled mode of the hybrid recoil mass analyzer present at the Inter University Accelerator Centre (IUAC), New Delhi. Theoretical calculations based on a statistical model were carried out incorporating an adjustable barrier scaling factor to fit the experimental ER cross section. Coupled-channel calculations were also performed using the ccfull code to obtain the spin distribution of the CN, which was used as an input in the calculations. Results: Experimental ER cross sections for 48Ti+Nd,150142 were found to be considerably smaller than the statistical model predictions whereas experimental and statistical model predictions for 48Ti+144Sm were of comparable magnitudes. Conclusion: Though comparison of experimental ER cross sections with statistical model predictions indicate considerable non-compound-nuclear processes for 48Ti+Nd,150142 reactions, no such evidence is found for the 48Ti+144Sm system. Further investigations are required to understand the difference in fusion probabilities of 48Ti+142Nd and 48Ti+144Sm systems.

  7. A dependence of quasielastic charged-current neutrino-nucleus cross sections

    NASA Astrophysics Data System (ADS)

    Van Dessel, N.; Jachowicz, N.; González-Jiménez, R.; Pandey, V.; Van Cuyck, T.

    2018-04-01

    Background: 12C has been and is still widely used in neutrino-nucleus scattering and oscillation experiments. More recently, 40Ar has emerged as an important nuclear target for current and future experiments. Liquid argon time projection chambers (LArTPCs) possess various advantages in measuring electroweak neutrino-nucleus cross sections. Concurrent theoretical research is an evident necessity. Purpose: 40Ar is larger than 12C , and one expects nuclear effects to play a bigger role in reactions. We present inclusive differential and total cross section results for charged-current neutrino scattering on 40Ar and perform a comparison with 12C , 16O , and 56Fe targets, to find out about the A -dependent behavior of model predictions. Method: Our model starts off with a Hartree-Fock description of the nucleus, with the nucleons interacting through a mean field generated by an effective Skyrme force. Long-range correlations are introduced by means of a continuum random phase approximation approach. Further methods to improve the accuracy of model predictions are also incorporated in the calculations. Results: We present calculations for 12C , 16O , 40Ar , and 56Fe , showcasing differential cross sections over a broad range of kinematic values in the quasielastic regime. We furthermore show flux-folded results for 40Ar and we discuss the differences between nuclear responses. Conclusions: At low incoming energies and forward scattering we identify an enhancement in the 40Ar cross section compared to 12C , as well as in the high ω (low Tμ) region across the entire studied Eν range. The contribution to the folded cross section of the reaction strength at values of ω lower than 50 MeV for forward scattering is sizable.

  8. N/Z effect on reaction mechanisms cross sections in the 78Kr + 40Ca and 86Kr + 48Ca collisions at 10A MeV

    NASA Astrophysics Data System (ADS)

    Gnoffo, B.; Pirrone, S.; Politi, G.; La Commara, M.; Wieleczko, J. P.; De Filippo, E.; Russotto, P.; Trimarchi, M.; Vigilante, M.; Ademard, G.; Auditore, L.; Beck, C.; Bercenau, I.; Bonnet, E.; Borderie, B.; Cardella, G.; Chibihi, A.; Colonna, M.; De Luca, S.; Dell'Aquila, D.; D'Onofrio, A.; Frankland, J. D.; Lanzalone, G.; Lautesse, P.; Lebhertz, D.; Le Neidre, N.; Lombardo, I.; Martorana, N. S.; Mazurek, N.; Norella, S.; Pagano, A.; Pagano, E. V.; Papa, M.; Piasecki, E.; Porto, F.; Quattrocchi, L.; Rizzo, F.; Spadaccini, G.; Trifirò, A.; Verde, G.

    2017-11-01

    Nuclear reactions between medium-mass nuclei at low bombarding energy are characterized by the competition between binary and evaporation processes in the compound nucleus decay. A study of the influence of the neutron richness of the entrance channel on the decay paths of the compound nuclei formed in the 78Kr + 40Ca and 86Kr + 48Ca at 10MeV/A is presented. The experiment has been performed at Laboratori Nazionali del Sud by using the CHIMERA 4 π multidetector for charged particles. The kinematical characteristics of the two reactions support the conclusion of a production of the IMFs via long-lived system and the global features suggest a different competition among the various reaction channels. The cross sections of the mechanisms responsible for the fragments production have been extracted. Besides the results relative to the n-poor system are compared to those obtained at GANIL, performed at 5.5A MeV, in order to study the energy influence on the mechanisms.

  9. New production cross sections for the theranostic radionuclide 67Cu

    NASA Astrophysics Data System (ADS)

    Pupillo, Gaia; Sounalet, Thomas; Michel, Nathalie; Mou, Liliana; Esposito, Juan; Haddad, Férid

    2018-01-01

    The cross sections of the 68Zn(p,2p)67Cu, 68Zn(p,2n)67Ga and 68Zn(p,3n)66Ga reactions were measured at the ARRONAX facility by using the 70 MeV cyclotron, with particular attention to the production of the theranostic radionuclide 67Cu. Enriched 68Zn material was electroplated on silver backing and exposed to a low-intensity proton beam by using the stacked-foils target method. Since 67Cu and 67Ga radionuclides have similar half-lives and same γ-lines (they both decay to 67Zn), a radiochemical process aimed at Cu/Ga separation was mandatory to avoid interferences in γ-spectrometry measurements. A simple chemical procedure having a high separation efficiency (>99%) was developed and monitored during each foil processing, thanks to the tracer isotopes 61Cu and 66Ga. Nuclear cross sections were measured in the energy range 35-70 MeV by using reference reactions recommended by the International Atomic Energy Agency (IAEA) to monitor beam flux. In comparison with literature data a general good agreement on the trend of the nuclear reactions was noted, especially with latest measurements, but slightly lower values were obtained in case of 67Cu. Experimental results of the 68Zn(p,2p)67Cu, 68Zn(p,2n)67Ga and 68Zn(p,3n)66Ga reactions were also compared with the theoretical values estimated by using the software TALYS. The production yield of the theranostic radionuclide 67Cu was estimated considering the results obtained in this work.

  10. Activation cross-sections of proton induced reactions on natHf in the 38-65 MeV energy range: Production of 172Lu and of 169Yb

    NASA Astrophysics Data System (ADS)

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

    2018-07-01

    In the frame of a systematical study of light ion induced nuclear reactions on hafnium, activation cross sections for proton induced reactions were investigated. Excitation functions were measured in the 38-65 MeV energy range for the natHf(p,xn)180g,177,176,175,173Ta, natHf(p,x)180m,179m,175,173,172,171Hf, 177g,173,172,171,170,169Lu and natHf(p,x)169Yb reactions by using the activation method, combining stacked foil irradiation and off line gamma ray spectroscopy. The experimental results are compared with earlier results in the overlapping energy range, and with the theoretical predictions of the ALICE IPPE and EMPIRE theoretical codes and of the TALYS code reported in the TENDL-2015 and TENDL-2017 libraries. The production routes of 172Lu (and its parent 172Hf) and of 169Yb are reviewed.

  11. Measurement of the neutrino-oxygen neutral-current interaction cross section by observing nuclear deexcitation γ rays

    NASA Astrophysics Data System (ADS)

    Abe, K.; Adam, J.; Aihara, H.; Akiri, T.; Andreopoulos, C.; Aoki, S.; Ariga, A.; Ariga, T.; Assylbekov, S.; Autiero, D.; Barbi, M.; Barker, G. J.; Barr, G.; Bass, M.; Batkiewicz, M.; Bay, F.; Bentham, S. W.; Berardi, V.; Berger, B. E.; Berkman, S.; Bertram, I.; Bhadra, S.; Blaszczyk, F. d. M.; Blondel, A.; Bojechko, C.; Bordoni, S.; Boyd, S. B.; Brailsford, D.; Bravar, A.; Bronner, C.; Buchanan, N.; Calland, R. G.; Caravaca Rodríguez, J.; Cartwright, S. L.; Castillo, R.; Catanesi, M. G.; Cervera, A.; Cherdack, D.; Christodoulou, G.; Clifton, A.; Coleman, J.; Coleman, S. J.; Collazuol, G.; Connolly, K.; Cremonesi, L.; Dabrowska, A.; Danko, I.; Das, R.; Davis, S.; de Perio, P.; De Rosa, G.; Dealtry, T.; Dennis, S. R.; Densham, C.; Dewhurst, D.; Di Lodovico, F.; Di Luise, S.; Drapier, O.; Duboyski, T.; Duffy, K.; Dufour, F.; Dumarchez, J.; Dytman, S.; Dziewiecki, M.; Emery-Schrenk, S.; Ereditato, A.; Escudero, L.; Finch, A. J.; Fiorentini Aguirre, G. A.; Friend, M.; Fujii, Y.; Fukuda, Y.; Furmanski, A. P.; Galymov, V.; Gaudin, A.; Giffin, S.; Giganti, C.; Gilje, K.; Goeldi, D.; Golan, T.; Gomez-Cadenas, J. J.; Gonin, M.; Grant, N.; Gudin, D.; Hadley, D. R.; Haegel, L.; Haesler, A.; Haigh, M. D.; Hamilton, P.; Hansen, D.; Hara, T.; Hartz, M.; Hasegawa, T.; Hastings, N. C.; Hayato, Y.; Hearty, C.; Helmer, R. L.; Hierholzer, M.; Hignight, J.; Hillairet, A.; Himmel, A.; Hiraki, T.; Hirota, S.; Holeczek, J.; Horikawa, S.; Huang, K.; Ichikawa, A. K.; Ieki, K.; Ieva, M.; Ikeda, M.; Imber, J.; Insler, J.; Irvine, T. J.; Ishida, T.; Ishii, T.; Ives, S. J.; Iwai, E.; Iwamoto, K.; Iyogi, K.; Izmaylov, A.; Jacob, A.; Jamieson, B.; Johnson, R. A.; Johnson, S.; Jo, J. H.; Jonsson, P.; Jung, C. K.; Kabirnezhad, M.; Kaboth, A. C.; Kajita, T.; Kakuno, H.; Kameda, J.; Kanazawa, Y.; Karlen, D.; Karpikov, I.; Katori, T.; Kearns, E.; Khabibullin, M.; Khotjantsev, A.; Kielczewska, D.; Kikawa, T.; Kilinski, A.; Kim, J.; King, S.; Kisiel, J.; Kitching, P.; Kobayashi, T.; Koch, L.; Kolaceke, A.; Konaka, A.; Kormos, L. L.; Korzenev, A.; Koseki, K.; Koshio, Y.; Kreslo, I.; Kropp, W.; Kubo, H.; Kudenko, Y.; Kumaratunga, S.; Kurjata, R.; Kutter, T.; Lagoda, J.; Laihem, K.; Lamont, I.; Larkin, E.; Laveder, M.; Lawe, M.; Lazos, M.; Lee, K. P.; Licciardi, C.; Lindner, T.; Lister, C.; Litchfield, R. P.; Longhin, A.; Ludovici, L.; Macaire, M.; Magaletti, L.; Mahn, K.; Malek, M.; Manly, S.; Marino, A. D.; Marteau, J.; Martin, J. F.; Martynenko, S.; Maruyama, T.; Marzec, J.; Mathie, E. L.; Matveev, V.; Mavrokoridis, K.; Mazzucato, E.; McCarthy, M.; McCauley, N.; McFarland, K. S.; McGrew, C.; Mefodiev, A.; Metelko, C.; Mezzetto, M.; Mijakowski, P.; Miller, C. A.; Minamino, A.; Mineev, O.; Mine, S.; Missert, A.; Miura, M.; Monfregola, L.; Moriyama, S.; Mueller, Th. A.; Murakami, A.; Murdoch, M.; Murphy, S.; Myslik, J.; Nagasaki, T.; Nakadaira, T.; Nakahata, M.; Nakai, T.; Nakamura, K.; Nakayama, S.; Nakaya, T.; Nakayoshi, K.; Nantais, C.; Naples, D.; Nielsen, C.; Nirkko, M.; Nishikawa, K.; Nishimura, Y.; Nowak, J.; O'Keeffe, H. M.; Ohta, R.; Okumura, K.; Okusawa, T.; Oryszczak, W.; Oser, S. M.; Ovsyannikova, T.; Owen, R. A.; Oyama, Y.; Palladino, V.; Palomino, J. L.; Paolone, V.; Payne, D.; Pearce, G. F.; Perevozchikov, O.; Perkin, J. D.; Petrov, Y.; Pickard, L.; Pinzon Guerra, E. S.; Pistillo, C.; Plonski, P.; Poplawska, E.; Popov, B.; Posiadala-Zezula, M.; Poutissou, J.-M.; Poutissou, R.; Przewlocki, P.; Quilain, B.; Radicioni, E.; Ratoff, P. N.; Ravonel, M.; Rayner, M. A. M.; Redij, A.; Reeves, M.; Reinherz-Aronis, E.; Riccio, C.; Retiere, F.; Robert, A.; Rodrigues, P. A.; Rojas, P.; Rondio, E.; Roth, S.; Rubbia, A.; Ruterbories, D.; Sacco, R.; Sakashita, K.; Sánchez, F.; Sato, F.; Scantamburlo, E.; Scholberg, K.; Schoppmann, S.; Schwehr, J.; Scott, M.; Seiya, Y.; Sekiguchi, T.; Sekiya, H.; Sgalaberna, D.; Shaker, F.; Shiozawa, M.; Short, S.; Shustrov, Y.; Sinclair, P.; Smith, B.; Smith, R. J.; Smy, M.; Sobczyk, J. T.; Sobel, H.; Sorel, M.; Southwell, L.; Stamoulis, P.; Steinmann, J.; Still, B.; Suda, Y.; Suzuki, A.; Suzuki, K.; Suzuki, S. Y.; Suzuki, Y.; Szeglowski, T.; Tacik, R.; Tada, M.; Takahashi, S.; Takeda, A.; Takeuchi, Y.; Tanaka, H. K.; Tanaka, H. A.; Tanaka, M. M.; Taylor, I. J.; Terhorst, D.; Terri, R.; Thompson, L. F.; Thorley, A.; Tobayama, S.; Toki, W.; Tomura, T.; Totsuka, Y.; Touramanis, C.; Tsukamoto, T.; Tzanov, M.; Uchida, Y.; Ueno, K.; Vacheret, A.; Vagins, M.; Vasseur, G.; Wachala, T.; Waldron, A. V.; Walter, C. W.; Wark, D.; Wascko, M. O.; Weber, A.; Wendell, R.; Wilkes, R. J.; Wilking, M. J.; Wilkinson, C.; Williamson, Z.; Wilson, J. R.; Wilson, R. J.; Wongjirad, T.; Yamada, Y.; Yamamoto, K.; Yanagisawa, C.; Yano, T.; Yen, S.; Yershov, N.; Yokoyama, M.; Yuan, T.; Yu, M.; Zalewska, A.; Zalipska, J.; Zambelli, L.; Zaremba, K.; Ziembicki, M.; Zimmerman, E. D.; Zito, M.; Żmuda, J.; T2K Collaboration

    2014-10-01

    We report the first measurement of the neutrino-oxygen neutral-current quasielastic (NCQE) cross section. It is obtained by observing nuclear deexcitation γ rays which follow neutrino-oxygen interactions at the Super-Kamiokande water Cherenkov detector. We use T2K data corresponding to 3.01 ×1 020 protons on target. By selecting only events during the T2K beam window and with well-reconstructed vertices in the fiducial volume, the large background rate from natural radioactivity is dramatically reduced. We observe 43 events in the 4-30 MeV reconstructed energy window, compared with an expectation of 51.0, which includes an estimated 16.2 background events. The background is primarily nonquasielastic neutral-current interactions and has only 1.2 events from natural radioactivity. The flux-averaged NCQE cross section we measure is 1.55 ×1 0-38 cm2 with a 68% confidence interval of (1.22 ,2.20 )×1 0-38 cm2 at a median neutrino energy of 630 MeV, compared with the theoretical prediction of 2.01 ×1 0-38 cm2 .

  12. Measurement of formation cross-section of 99Mo from the 98Mo(n,γ) and 100Mo(n,2n) reactions.

    PubMed

    Badwar, Sylvia; Ghosh, Reetuparna; Lawriniang, Bioletty M; Vansola, Vibha; Sheela, Y S; Naik, Haladhara; Naik, Yeshwant; Suryanarayana, Saraswatula V; Jyrwa, Betylda; Ganesan, Srinivasan

    2017-11-01

    The formation cross-section of medical isotope 99 Mo from the 98 Mo(n,γ) reaction at the neutron energy of 0.025eV and from the 100 Mo(n,2n) reaction at the neutron energies of 11.9 and 15.75MeV have been determined by using activation and off-line γ-ray spectrometric technique. The thermal neutron energy of 0.025eV was used from the reactor critical facility at BARC, Mumbai, whereas the average neutron energies of 11.9 and 15.75MeV were generated using 7 Li(p,n) reaction in the Pelletron facility at TIFR, Mumbai. The experimentally determined cross-sections were compared with the evaluated nuclear data libraries of ENDF/B-VII.1, CENDL-3.1, JENDL-4.0 and JEFF-3.2 and are found to be in close agreement. The 100 Mo(n,2n) 99 Mo reaction cross-sections were also calculated theoretically by using TALYS-1.8 and EMPIRE-3.2 computer codes and compared with the experimental data. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. An analysis of MCNP cross-sections and tally methods for low-energy photon emitters.

    PubMed

    Demarco, John J; Wallace, Robert E; Boedeker, Kirsten

    2002-04-21

    Monte Carlo calculations are frequently used to analyse a variety of radiological science applications using low-energy (10-1000 keV) photon sources. This study seeks to create a low-energy benchmark for the MCNP Monte Carlo code by simulating the absolute dose rate in water and the air-kerma rate for monoenergetic point sources with energies between 10 keV and 1 MeV. The analysis compares four cross-section datasets as well as the tally method for collision kerma versus absorbed dose. The total photon attenuation coefficient cross-section for low atomic number elements has changed significantly as cross-section data have changed between 1967 and 1989. Differences of up to 10% are observed in the photoelectric cross-section for water at 30 keV between the standard MCNP cross-section dataset (DLC-200) and the most recent XCOM/NIST tabulation. At 30 keV, the absolute dose rate in water at 1.0 cm from the source increases by 7.8% after replacing the DLC-200 photoelectric cross-sections for water with those from the XCOM/NIST tabulation. The differences in the absolute dose rate are analysed when calculated with either the MCNP absorbed dose tally or the collision kerma tally. Significant differences between the collision kerma tally and the absorbed dose tally can occur when using the DLC-200 attenuation coefficients in conjunction with a modern tabulation of mass energy-absorption coefficients.

  14. Statistical Model Analysis of (n,p) Cross Sections and Average Energy For Fission Neutron Spectrum

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Odsuren, M.; Khuukhenkhuu, G.

    2011-06-28

    Investigation of charged particle emission reaction cross sections for fast neutrons is important to both nuclear reactor technology and the understanding of nuclear reaction mechanisms. In particular, the study of (n,p) cross sections is necessary to estimate radiation damage due to hydrogen production, nuclear heating and transmutations in the structural materials of fission and fusion reactors. On the other hand, it is often necessary in practice to evaluate the neutron cross sections of the nuclides for which no experimental data are available.Because of this, we carried out the systematical analysis of known experimental (n,p) and (n,a) cross sections for fastmore » neutrons and observed a systematical regularity in the wide energy interval of 6-20 MeV and for broad mass range of target nuclei. To explain this effect using the compound, pre-equilibrium and direct reaction mechanisms some formulae were deduced. In this paper, in the framework of the statistical model known experimental (n,p) cross sections averaged over the thermal fission neutron spectrum of U-235 are analyzed. It was shown that the experimental data are satisfactorily described by the statistical model. Also, in the case of (n,p) cross sections the effective average neutron energy for fission spectrum of U-235 was found to be around 3 MeV.« less

  15. Coupled neutron--gamma multigroup--multitable cross sections for 29 materials pertinent to nuclear weapons effect calculations generated by LASL/TD Division

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sandmeier, H.A.; Hansen, G.E.; Seamon, R.E.

    This report lists 42-group, coupled, neutron -gamma cross sections for H, D, T, /sup 3/He, /sup 4/He, /sup 6/Li, /sup 7/Li, Be, /sup 10/B, /sup 11/B, C, N, O, Na, Mg, Ai, Si, Cl, A, K, Ca, Fe, Cu, W, Pb, /sup 235/U, /sup 238/U, / sup 239/Pu, and /sup 240/Pu. Most of these materials are used in nuclear- weaponseffects calculations, where the elements for air, ground, and sea water are needed. Further, lists are given of cross sections for materials used in nuclear weapons vulnerability calculations, such as the elements of high explosives as well as materials that willmore » undergo fusion and fission. Most of the common reactor materials are also listed. The 42 coupled neutron-gamma groups are split into 30 neutron groups (17 MeV through 1.39 x 10/sup -4/ eV) and 12 gamma groups (10 MeV through 0.01 MeV). Data sources and averaging schemes used for the development of these multigroup parameters are given. (119 tables) (auth)« less

  16. Proton and deuteron double differential cross sections at angles from 10 deg to 60 deg from Be, C, Al, Fe, Cu, Ge, W, and Pb under 558-MeV-proton irradiation

    NASA Technical Reports Server (NTRS)

    Beck, S. M.; Powell, C. A.

    1976-01-01

    The double differential cross sections for the production of protons and deuterons from targets of Be, C, Al, Fe, Cu, Ge, W, and Pb were obtained at laboratory angles of scatter of 10, 20, 30, 40, 50, and 60 degrees for 558-MeV incident protons. The position of the quasi-elastic peak, discernible in the cross sections up to approximately 40 degrees, corresponded closely to the theoretical predictions for proton-proton elastic scattering at 558 MeV. The mean ratio of deuteron to proton energy-integrated cross sections was 0.056 + or - 0.008. The dependence of energy-integrated cross sections for both protons and deuterons on target mass number A varied from A to the 1/3 power at 10 degrees to A to the 2/3 power above approximately 30 degrees. The ratio of energy-integrated deuteron cross sections for quasielastic processes to that for reactions yielding a deuteron-pi-meson pair was approximately 10 percent.

  17. Deuteron-induced reactions on Ni isotopes up to 60 MeV

    NASA Astrophysics Data System (ADS)

    Avrigeanu, M.; Šimečková, E.; Fischer, U.; Mrázek, J.; Novak, J.; Štefánik, M.; Costache, C.; Avrigeanu, V.

    2016-07-01

    Background: The high complexity of the deuteron-nucleus interaction from the deuteron weak binding energy of 2.224 MeV is also related to a variety of reactions induced by the deuteron-breakup (BU) nucleons. Thus, specific noncompound processes as BU and direct reactions (DR) make the deuteron-induced reactions so different from reactions with other incident particles. The scarce consideration of only pre-equilibrium emission (PE) and compound-nucleus (CN) mechanisms led to significant discrepancies with experimental results so that recommended reaction cross sections of high-priority elements as, e.g., Ni have mainly been obtained by fit of the data. Purpose: The unitary and consistent BU and DR account in deuteron-induced reactions on natural nickel may take advantage of an extended database for this element, including new accurate measurements of particular reaction cross sections. Method: The activation cross sections of 64,61,60Cu, Ni,5765, and 55,56,57,58,59m,60Co nuclei for deuterons incident on natural Ni at energies up to 20 MeV, were measured by the stacked-foil technique and high-resolution gamma spectrometry using U-120M cyclotron of CANAM, NPI CAS. Then, within an extended analysis of deuteron interactions with Ni isotopes up to 60 MeV, all processes from elastic scattering until the evaporation from fully equilibrated compound system have been taken into account while an increased attention is paid especially to the BU and DR mechanisms. Results: The deuteron activation cross-section analysis, completed by consideration of the PE and CN contributions corrected for decrease of the total-reaction cross section from the leakage of the initial deuteron flux towards BU and DR processes, is proved satisfactory for the first time to all available data. Conclusions: The overall agreement of the measured data and model calculations validates the description of nuclear mechanisms taken into account for deuteron-induced reactions on Ni, particularly the BU and

  18. Theoretical estimates of supernova-neutrino cross sections for the stable even-even lead isotopes: Charged-current reactions

    NASA Astrophysics Data System (ADS)

    Almosly, W.; Carlsson, B. G.; Suhonen, J.; Toivanen, J.; Ydrefors, E.

    2016-10-01

    A detailed study of the charged-current supernova electron neutrino and electron antineutrino scattering off the stable even-mass lead isotopes A =204 , 206, and 208 is reported in this work. The proton-neutron quasiparticle random-phase approximation (pnQRPA) is adopted to construct the nuclear final and initial states. Three different Skyrme interactions are tested for their isospin and spin-isospin properties and then applied to produce (anti)neutrino-nucleus scattering cross sections for (anti)neutrino energies below 80 MeV. Realistic estimates of the nuclear responses to supernova (anti)neutrinos are computed by folding the computed cross sections with a two-parameter Fermi-Dirac distribution of the electron (anti)neutrino energies. The computed cross sections are compared with earlier calculations and the analyses are extended to take into account the effects coming from the neutrino oscillations.

  19. Cross section measurements at LANSCE for defense, science and applications

    DOE PAGES

    Nelson, Ronald O.; Schwengner, R.; Zuber, K.

    2015-05-28

    The Los Alamos Neutron Science Center (LANSCE) has three neutron sources that are used for nuclear science measurements. These sources are driven by an 800 MeV proton linear accelerator and cover an energy range from sub-thermal to hundreds of MeV. Research at the facilities is performed under the auspices of a US DOE user program under which research proposals are rated for merit by a program advisory committee and are scheduled based on merit and availability of beam time. A wide variety of instruments is operated at the neutron flight paths at LANSCE including neutron detector arrays, gamma-ray detector arrays,more » fission fragment detectors, and charged particle detectors. These instruments provide nuclear data for multiple uses that range from increasing knowledge in fundamental science to satisfying data needs for diverse applications such as nuclear energy, global security, and industrial applications. In addition, highlights of recent research related to cross sections measurements are presented, and future research initiatives are discussed.« less

  20. Measurement of νμ and ν¯μ induced neutral current single π0 production cross sections on mineral oil at Eν˜O (1 GeV)

    NASA Astrophysics Data System (ADS)

    Aguilar-Arevalo, A. A.; Anderson, C. E.; Bazarko, A. O.; Brice, S. J.; Brown, B. C.; Bugel, L.; Cao, J.; Coney, L.; Conrad, J. M.; Cox, D. C.; Curioni, A.; Djurcic, Z.; Finley, D. A.; Fleming, B. T.; Ford, R.; Garcia, F. G.; Garvey, G. T.; Gonzales, J.; Grange, J.; Green, C.; Green, J. A.; Hart, T. L.; Hawker, E.; Imlay, R.; Johnson, R. A.; Karagiorgi, G.; Kasper, P.; Katori, T.; Kobilarcik, T.; Kourbanis, I.; Koutsoliotas, S.; Laird, E. M.; Linden, S. K.; Link, J. M.; Liu, Y.; Liu, Y.; Louis, W. C.; Mahn, K. B. M.; Marsh, W.; Mauger, C.; McGary, V. T.; McGregor, G.; Metcalf, W.; Meyers, P. D.; Mills, F.; Mills, G. B.; Monroe, J.; Moore, C. D.; Mousseau, J.; Nelson, R. H.; Nienaber, P.; Nowak, J. A.; Osmanov, B.; Ouedraogo, S.; Patterson, R. B.; Pavlovic, Z.; Perevalov, D.; Polly, C. C.; Prebys, E.; Raaf, J. L.; Ray, H.; Roe, B. P.; Russell, A. D.; Sandberg, V.; Schirato, R.; Schmitz, D.; Shaevitz, M. H.; Shoemaker, F. C.; Smith, D.; Soderberg, M.; Sorel, M.; Spentzouris, P.; Spitz, J.; Stancu, I.; Stefanski, R. J.; Sung, M.; Tanaka, H. A.; Tayloe, R.; Tzanov, M.; de Water, R. G. Van; Wascko, M. O.; White, D. H.; Wilking, M. J.; Yang, H. J.; Zeller, G. P.; Zimmerman, E. D.; MiniBooNE Collaboration

    2010-01-01

    MiniBooNE reports the first absolute cross sections for neutral current single π0 production on CH2 induced by neutrino and antineutrino interactions measured from the largest sets of NC π0 events collected to date. The principal result consists of differential cross sections measured as functions of π0 momentum and π0 angle averaged over the neutrino flux at MiniBooNE. We find total cross sections of (4.76±0.05stat±0.76sys)×10-40cm2/nucleon at a mean energy of ⟨Eν⟩=808MeV and (1.48±0.05stat±0.23sys)×10-40cm2/nucleon at a mean energy of ⟨Eν⟩=664MeV for νμ and ν¯μ induced production, respectively. In addition, we have included measurements of the neutrino and antineutrino total cross sections for incoherent exclusive NC 1π0 production corrected for the effects of final state interactions to compare to prior results.

  1. Cross-Section Measurements via the Activation Technique at the Cologne Clover Counting Setup

    NASA Astrophysics Data System (ADS)

    Heim, Felix; Mayer, Jan; Netterdon, Lars; Scholz, Philipp; Zilges, Andreas

    The activation technique is a widely used method for the determination of cross-section values for charged-particle induced reactions at astrophysically relevant energies. Since network calculations of nucleosynthesis processes often depend on reaction rates calculated in the scope of the Hauser-Feshbach statistical model, these cross-sections can be used to improve the nuclear-physics input-parameters like optical-model potentials (OMP), γ-ray strength functions, and nuclear level densities. In order to extend the available experimental database, the 108Cd(α, n)111Sn reaction cross section was investigated at ten energies between 10.2 and 13.5 MeV. As this reaction at these energies is almost only sensitive on the α-decay width, the results were compared to statistical model calculations using different models for the α-OMP. The irradiation as well as the consecutive γ-ray counting were performed at the Institute for Nuclear Physics of the University of Cologne using the 10 MV FN-Tandem accelerator and the Cologne Clover Counting Setup. This setup consists of two clover- type high purity germanium (HPGe) detectors in a close face-to-face geometry to cover a solid angle of almost 4π.

  2. Transport analysis of measured neutron leakage spectra from spheres as tests of evaluated high energy cross sections

    NASA Technical Reports Server (NTRS)

    Bogart, D. D.; Shook, D. F.; Fieno, D.

    1973-01-01

    Integral tests of evaluated ENDF/B high-energy cross sections have been made by comparing measured and calculated neutron leakage flux spectra from spheres of various materials. An Am-Be (alpha,n) source was used to provide fast neutrons at the center of the test spheres of Be, CH2, Pb, Nb, Mo, Ta, and W. The absolute leakage flux spectra were measured in the energy range 0.5 to 12 MeV using a calibrated NE213 liquid scintillator neutron spectrometer. Absolute calculations of the spectra were made using version 3 ENDF/B cross sections and an S sub n discrete ordinates multigroup transport code. Generally excellent agreement was obtained for Be, CH2, Pb, and Mo, and good agreement was observed for Nb although discrepancies were observed for some energy ranges. Poor comparative results, obtained for Ta and W, are attributed to unsatisfactory nonelastic cross sections. The experimental sphere leakage flux spectra are tabulated and serve as possible benchmarks for these elements against which reevaluated cross sections may be tested.

  3. γ production and neutron inelastic scattering cross sections for 76Ge

    NASA Astrophysics Data System (ADS)

    Rouki, C.; Domula, A. R.; Drohé, J. C.; Koning, A. J.; Plompen, A. J. M.; Zuber, K.

    2013-11-01

    The 2040.7-keV γ ray from the 69th excited state of 76Ge was investigated in the interest of Ge-based double-β-decay experiments like the Germanium Detector Array (GERDA) experiment. The predicted transition could interfere with valid 0νββ events at 2039.0 keV, creating false signals in large-volume 76Ge enriched detectors. The measurement was performed with the Gamma Array for Inelastic Neutron Scattering (GAINS) at the Geel Electron Linear Accelerator (GELINA) white neutron source, using the (n,n'γ) technique and focusing on the strongest γ rays originating from the level. Upper limits obtained for the production cross section of the 2040.7-keV γ ray showed no possible influence on GERDA data. Additional analysis of the data yielded high-resolution cross sections for the low-lying states of 76Ge and related γ rays, improving the accuracy and extending existing data for five transitions and five levels. The inelastic scattering cross section for 76Ge was determined for incident neutron energies up to 2.23 MeV, significantly increasing the energy range for which experimental data are available. Comparisons with model calculations using the talys code are presented indicating that accounting for the recently established asymmetric rotor structure should lead to an improved description of the data.

  4. M-shell x-ray production cross sections for 19 elements in the range Z=54-92 by H/sup +/, He/sup +/ and He/sup + +/ ions from 300 keV to 40 MeV. [Xe, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Yb, Hf, Ta, W, Pt, Au, Hg, Pb, Bi, and U

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mehta, R.; Duggan, J.L.; Kocur, P.M.

    1983-04-01

    In this report, the measurements done over the last three decades at various laboratories are surveyed. The elements studied were Xe, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Yb, Hf, Ta, W, Pt, Au, Hg, Pb, Bi, and U. The projectile energies investigated range from 300 keV to 40 MeV for the protons and 250 keV to 2.5 MeV for He/sup +/ ions. Also reported are the M-shell x-ray production cross sections of some rare-earth elements recently measured at NTSU. For these measurements the energy of incident /sup 1/H/sup +/ and /sup 4/He/sup +/ ions ranged from 0.25 tomore » 2.5 MeV. The experimental data are compared to the M-shell ionization cross section predictions of first Born approximation, i.e. the PWBA for direct ionization plus the OBK of Nikolaev for electron capture. Comparison is also made with the theory by Brandt and Lapicki that goes beyond the first Born approximation, i.e. the ECPSSR approach which accounts for the Energy loss, Coulomb deflection and Relativistic effects in the Perturbed Stationary State theory.« less

  5. Theoretical detection limit of PIXE analysis using 20 MeV proton beams

    NASA Astrophysics Data System (ADS)

    Ishii, Keizo; Hitomi, Keitaro

    2018-02-01

    Particle-induced X-ray emission (PIXE) analysis is usually performed using proton beams with energies in the range 2∼3 MeV because at these energies, the detection limit is low. The detection limit of PIXE analysis depends on the X-ray production cross-section, the continuous background of the PIXE spectrum and the experimental parameters such as the beam currents and the solid angle and detector efficiency of X-ray detector. Though the continuous background increases as the projectile energy increases, the cross-section of the X-ray increases as well. Therefore, the detection limit of high energy proton PIXE is not expected to increase significantly. We calculated the cross sections of continuous X-rays produced in several bremsstrahlung processes and estimated the detection limit of a 20 MeV proton PIXE analysis by modelling the Compton tail of the γ-rays produced in the nuclear reactions, and the escape effect on the secondary electron bremsstrahlung. We found that the Compton tail does not affect the detection limit when a thin X-ray detector is used, but the secondary electron bremsstrahlung escape effect does have an impact. We also confirmed that the detection limit of the PIXE analysis, when used with 4 μm polyethylene backing film and an integrated beam current of 1 μC, is 0.4∼2.0 ppm for proton energies in the range 10∼30 MeV and elements with Z = 16-90. This result demonstrates the usefulness of several 10 MeV cyclotrons for performing PIXE analysis. Cyclotrons with these properties are currently installed in positron emission tomography (PET) centers.

  6. Spin-flip isovector giant resonances from the 90Zr(n,p)90Y reaction at 198 MeV

    NASA Astrophysics Data System (ADS)

    Raywood, K. J.; Spicer, B. M.; Yen, S.; Long, S. A.; Moinester, M. A.; Abegg, R.; Alford, W. P.; Celler, A.; Drake, T. E.; Frekers, D.; Green, P. E.; Häusser, O.; Helmer, R. L.; Henderson, R. S.; Hicks, K. H.; Jackson, K. P.; Jeppesen, R. G.; King, J. D.; King, N. S.; Miller, C. A.; Officer, V. C.; Schubank, R.; Shute, G. G.; Vetterli, M.; Watson, J.; Yavin, A. I.

    1990-06-01

    Doubly differential cross sections of the reaction 90Zr(n,p)90Y have been measured at 198 MeV for excitations up to 38 MeV in the residual nucleus. An overall resolution of 1.3 MeV was achieved. The spectra show qualitative agreement in shape and magnitude with recent random phase approximation calculations; however, all of the calculations underestimate the high excitation region of the spectra. A multipole decomposition of the data has been performed using differential cross sections calculated in the distorted-wave impulse approximation. An estimate of the Gamow-Teller strength in the reaction is given. The isovector spin-flip dipole giant resonance has been identified and there is also an indication of isovector monopole strength.

  7. 3He(α, γ)7Be cross section in a wide energy range

    NASA Astrophysics Data System (ADS)

    Szücs, Tamás; Gyürky, György; Halász, Zoltán; Kiss, Gábor Gy.; Fülöp, Zsolt

    2018-01-01

    The reaction rate of the 3He(α,γ)7 Be reaction is important both in the Big Bang Nucleosynthesis (BBN) and in the Solar hydrogen burning. There have been a lot of experimental and theoretical efforts to determine this reaction rate with high precision. Some long standing issues have been solved by the more precise investigations, like the different S(0) values predicted by the activation and in-beam measurement. However, the recent, more detailed astrophysical model predictions require the reaction rate with even higher precision to unravel new issues like the Solar composition. One way to increase the precision is to provide a comprehensive dataset in a wide energy range, extending the experimental cross section database of this reaction. This paper presents a new cross section measurement between Ecm = 2.5 - 4.4 MeV, in an energy range which extends above the 7Be proton separation threshold.

  8. Peeling Off Neutron Skins from Neutron-Rich Nuclei: Constraints on the Symmetry Energy from Neutron-Removal Cross Sections

    NASA Astrophysics Data System (ADS)

    Aumann, T.; Bertulani, C. A.; Schindler, F.; Typel, S.

    2017-12-01

    An experimentally constrained equation of state of neutron-rich matter is fundamental for the physics of nuclei and the astrophysics of neutron stars, mergers, core-collapse supernova explosions, and the synthesis of heavy elements. To this end, we investigate the potential of constraining the density dependence of the symmetry energy close to saturation density through measurements of neutron-removal cross sections in high-energy nuclear collisions of 0.4 to 1 GeV /nucleon . We show that the sensitivity of the total neutron-removal cross section is high enough so that the required accuracy can be reached experimentally with the recent developments of new detection techniques. We quantify two crucial points to minimize the model dependence of the approach and to reach the required accuracy: the contribution to the cross section from inelastic scattering has to be measured separately in order to allow a direct comparison of experimental cross sections to theoretical cross sections based on density functional theory and eikonal theory. The accuracy of the reaction model should be investigated and quantified by the energy and target dependence of various nucleon-removal cross sections. Our calculations explore the dependence of neutron-removal cross sections on the neutron skin of medium-heavy neutron-rich nuclei, and we demonstrate that the slope parameter L of the symmetry energy could be constrained down to ±10 MeV by such a measurement, with a 2% accuracy of the measured and calculated cross sections.

  9. Cross sections for nuclide production in proton- and deuteron-induced reactions on 93Nb measured using the inverse kinematics method

    NASA Astrophysics Data System (ADS)

    Nakano, Keita; Watanabe, Yukinobu; Kawase, Shoichiro; Wang, He; Otsu, Hideaki; Sakurai, Hiroyoshi; Takeuchi, Satoshi; Togano, Yasuhiro; Nakamura, Takashi; Maeda, Yukie; Ahn, Deuk Soon; Aikawa, Masayuki; Araki, Shouhei; Chen, Sidong; Chiga, Nobuyuki; Doornenbal, Pieter; Fukuda, Naoki; Ichihara, Takashi; Isobe, Tadaaki; Kawakami, Shunsuke; Kin, Tadahiro; Kondo, Yosuke; Koyama, Shunpei; Kubo, Toshiyuki; Kubono, Shigeru; Kurokawa, Meiko; Makinaga, Ayano; Matsushita, Masafumi; Matsuzaki, Teiichiro; Michimasa, Shin'ichiro; Momiyama, Satoru; Nagamine, Shunsuke; Niikura, Megumi; Ozaki, Tomoyuki; Saito, Atsumi; Saito, Takeshi; Shiga, Yoshiaki; Shikata, Mizuki; Shimizu, Yohei; Shimoura, Susumu; Sumikama, Toshiyuki; Söderström, Pär-Anders; Suzuki, Hiroshi; Takeda, Hiroyuki; Taniuchi, Ryo; Tsubota, Jun'ichi; Watanabe, Yasushi; Wimmer, Kathrin; Yamamoto, Tatsuya; Yoshida, Koichi

    2017-09-01

    Isotopic production cross sections were measured for proton- and deuteron-induced reactions on 93Nb by means of the inverse kinematics method at RIKEN Radioactive Isotope Beam Factory. The measured production cross sections of residual nuclei in the reaction 93Nb + p at 113 MeV/u were compared with previous data measured by the conventional activation method in the proton energy range between 46 and 249 MeV. The present inverse kinematics data of four reaction products (90Mo, 90Nb, 88Y, and 86Y) were in good agreement with the data of activation measurement. Also, the model calculations with PHITS describing the intra-nuclear cascade and evaporation processes generally well reproduced the measured isotopic production cross sections.

  10. The fission cross sections of /sup 230/Th, /sup 232/Th, /sup 233/U, /sup 234/U, /sup 236/U, /sup 238/U, /sup 237/Np, /sup 239/Pu and /sup 242/Pu relative /sup 235/U at 14. 74 MeV neutron energy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Meadows, J.W.

    1986-12-01

    The measurement of the fission cross section ratios of nine isotopes relative to /sup 235/U at an average neutron energy of 14.74 MeV is described with particular attention to the determination of corrections and to sources of error. The results are compared to ENDF/B-V and to other measurements of the past decade. The ratio of the neutron induced fission cross section for these isotopes to the fission cross section for /sup 235/U are: /sup 230/Th - 0.290 +- 1.9%; /sup 232/Th - 0.191 +- 1.9%; /sup 233/U - 1.132 +- 0.7%; /sup 234/U - 0.998 +- 1.0%; /sup 236/U -more » 0.791 +- 1.1%; /sup 238/U - 0.587 +- 1.1%; /sup 237/Np - 1.060 +- 1.4%; /sup 239/Pu - 1.152 +- 1.1%; /sup 242/Pu - 0.967 +- 1.0%. 40 refs., 11 tabs., 9 figs.« less

  11. Application of PIXE in the determination of the production cross section of a radionuclide decaying by electron capture

    NASA Astrophysics Data System (ADS)

    Morales, J. R.; Chesta, M. A.; Cancino, S. A.; Miranda, P. A.; Dinator, M. I.; Avila, M. J.

    2005-01-01

    Proton induced X-ray emission (PIXE) has been applied to the measurement of the production cross section of a radionuclide decaying by electron capture. By performing a PIXE type experiment on the daughter nuclide important advantages are obtained. The determination of some factors with usually large uncertainties, like solid angle and detector efficiency were avoided. The method was applied to the determination of cross section of the reaction 63Cu(d, p)64Cu at 2.4 MeV for 64Cu production. This result is in full agreement with that obtained through the decay of the 1346 keV gamma ray of 64Cu.

  12. Towards the measurement of the13C(d, p)14C cross section using AMS

    NASA Astrophysics Data System (ADS)

    Murillo-Morales, S.; Barrón-Palos, L.; Chávez, E.; Araujo-Escalona, V.

    2017-07-01

    A plan to study the total cross section for the13C(d, p)14C nuclear reaction has been developed for energies in the center-of-mass frame between 133 and 400 keV. The proposed experiment will use a deuterium beam (1-3 MeV of energy) from the Instituto de Física-UNAM 5.5 MV Van de Graaff accelerator and the produced14C will be afterwards measured by AMS technique in the LEMA-UNAM (HVEE 1 MV Tandetron). One of the main goals is to study the performance of the LEMA-UNAM facility in the cross section measurement in comparison with other data reported in the literature, measured by other techniques. In this work we present the current status of these studies. The relevance of the13C(d, p)14C reaction in the study of compound nucleus formation as well as in some astrophysics scenarios, and the importance of the development of the AMS technique to measure cross sections of nuclear reactions of astrophysical interest in Mixico are also discussed.

  13. Evaluation of neutron total and capture cross sections on 99Tc in the unresolved resonance region

    NASA Astrophysics Data System (ADS)

    Iwamoto, Nobuyuki; Katabuchi, Tatsuya

    2017-09-01

    Long-lived fission product Technetium-99 is one of the most important radioisotopes for nuclear transmutation. The reliable nuclear data are indispensable for a wide energy range up to a few MeV, in order to develop environmental load reducing technology. The statistical analyses of resolved resonances were performed by using the truncated Porter-Thomas distribution, coupled-channels optical model, nuclear level density model and Bayes' theorem on conditional probability. The total and capture cross sections were calculated by a nuclear reaction model code CCONE. The resulting cross sections have statistical consistency between the resolved and unresolved resonance regions. The evaluated capture data reproduce those recently measured at ANNRI of J-PARC/MLF above resolved resonance region up to 800 keV.

  14. Electron-Impact Ionization Cross Section Database

    National Institute of Standards and Technology Data Gateway

    SRD 107 Electron-Impact Ionization Cross Section Database (Web, free access)   This is a database primarily of total ionization cross sections of molecules by electron impact. The database also includes cross sections for a small number of atoms and energy distributions of ejected electrons for H, He, and H2. The cross sections were calculated using the Binary-Encounter-Bethe (BEB) model, which combines the Mott cross section with the high-incident energy behavior of the Bethe cross section. Selected experimental data are included.

  15. Neutron-neutron quasifree scattering in nd breakup at 10 MeV

    NASA Astrophysics Data System (ADS)

    Malone, R. C.; Crowe, B.; Crowell, A. S.; Cumberbatch, L. C.; Esterline, J. H.; Fallin, B. A.; Friesen, F. Q. L.; Han, Z.; Howell, C. R.; Markoff, D.; Ticehurst, D.; Tornow, W.; Witała, H.

    2016-03-01

    The neutron-deuteron (nd) breakup reaction provides a rich environment for testing theoretical models of the neutron-neutron (nn) interaction. Current theoretical predictions based on rigorous ab-initio calculations agree well with most experimental data for this system, but there remain a few notable discrepancies. The cross section for nn quasifree (QFS) scattering is one such anomaly. Two recent experiments reported cross sections for this particular nd breakup configuration that exceed theoretical calculations by almost 20% at incident neutron energies of 26 and 25 MeV [1, 2]. The theoretical values can be brought into agreement with these results by increasing the strength of the 1S0 nn potential matrix element by roughly 10%. However, this modification of the nn effective range parameter and/or the 1S0 scattering length causes substantial charge-symmetry breaking in the nucleon-nucleon force and suggests the possibility of a weakly bound di-neutron state [3]. We are conducting new measurements of the cross section for nn QFS in nd breakup. The measurements are performed at incident neutron beam energies below 20 MeV. The neutron beam is produced via the 2H(d, n)3He reaction. The target is a deuterated plastic cylinder. Our measurements utilize time-of-flight techniques with a pulsed neutron beam and detection of the two emitted neutrons in coincidence. A description of our initial measurements at 10 MeV for a single scattering angle will be presented along with preliminary results. Also, plans for measurements at other energies with broad angular coverage will be discussed.

  16. Neutron capture cross-section studies of Tellurium isotopes for neutrinoless double beta decay applications

    NASA Astrophysics Data System (ADS)

    Bhike, Megha; Tornow, Werner

    2014-09-01

    The CUORE detector at Gran Sasso, aimed at searching for neutrinoless double-beta decay of 130Te, employs an array of TeO2 bolometer modules. To understand and identify the contribution of muon and (α,n) induced neutrons to the CUORE background, fast neutron cature cross-section data of the tellurium isotopes 126Te, 128Te and 130Te have been measured with the activation method at eight different energies in the neutron energy range 0.5-7.5 MeV. Plastic pill boxes of diameter 1.6 cm and width 1 cm containing Te were irradiated with mono-energetic neutrons produced via the 3H(p,n)3He and 2H(d,n)3He reactions. The cross-sections were determined relative to the 197Au(n, γ)198Au and 115In(n,n')115m In standard cross sections. The activities of the products were measured using 60% lead-shielded HPGe detectors at TUNL's low background counting facility. The present results are compared with the evaluated data from TENDL-2012, ENDF/B-VII.1, JEFF-3.2 and JENDL-4.0, as well as with literature data.

  17. Effect of in-medium nucleon-nucleon cross section on proton-proton momentum correlation in intermediate-energy heavy-ion collisions

    NASA Astrophysics Data System (ADS)

    Wang, Ting-Ting; Ma, Yu-Gang; Zhang, Chun-Jian; Zhang, Zheng-Qiao

    2018-03-01

    The proton-proton momentum correlation function from different rapidity regions is systematically investigated for the Au + Au collisions at different impact parameters and different energies from 400 A MeV to 1500 A MeV in the framework of the isospin-dependent quantum molecular dynamics model complemented by the Lednický-Lyuboshitz analytical method. In particular, the in-medium nucleon-nucleon cross-section dependence of the correlation function is brought into focus, while the impact parameter and energy dependence of the momentum correlation function are also explored. The sizes of the emission source are extracted by fitting the momentum correlation functions using the Gaussian source method. We find that the in-medium nucleon-nucleon cross section obviously influences the proton-proton momentum correlation function, which is from the whole-rapidity or projectile or target rapidity region at smaller impact parameters, but there is no effect on the mid-rapidity proton-proton momentum correlation function, which indicates that the emission mechanism differs between projectile or target rapidity and mid-rapidity protons.

  18. Temperature-Dependent, Linearly Interpolable, Tabulated Cross Section Library Based on ENDF/B-VI, Release 8.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    CULLEN, D. E.

    2005-02-21

    Version 00 As distributed, the original evaluated data include cross sections represented in the form of a combination of resonance parameters and/or tabulated energy dependent cross sections, nominally at 0 Kelvin temperature. For use in applications this library has been processed into the form of temperature dependent cross sections at eight neutron reactor like temperatures, between 0 and 2100 Kelvin, in steps of 300 Kelvin. It has also been processed to five astrophysics like temperatures, 1, 10, 100 eV, 1 and 10 keV. For reference purposes, 300 Kelvin is approximately 1/40 eV, so that 1 eV is approximately 12,000 Kelvin.more » At each temperature the cross sections are tabulated and linearly interpolable in energy. POINT2004 contains all of the evaluations in the ENDF/B-VI general purpose library, which contains evaluations for 328 materials (isotopes or naturally occurring elemental mixtures of isotopes). No special purpose ENDF/B-VI libraries, such as fission products, thermal scattering, or photon interaction data are included. The majority of these evaluations are complete, in the sense that they include all cross sections over the energy range 10-5 eV to at least 20 MeV. However, the following are only partial evaluations that either contain only single reactions and no total cross section (Mg24, K41, Ti46, Ti47, Ti48, Ti50 and Ni59), or do not include energy dependent cross sections above the resonance region (Ar40, Mo92, Mo98, Mo100, In115, Sn120, Sn122 and Sn124). The CCC-638/TART20002 code package is recommended for use with these data. Codes within TART can be used to display these data or to run calculations using these data.« less

  19. Light ion induced L X-ray production cross-sections in Au and Pb

    NASA Astrophysics Data System (ADS)

    Ouziane, S.; Amokrane, A.; Toumert, I.

    2008-04-01

    Experimental proton-induced Lα, Lβ, Lγ, Lℓ and Ltot absolute X-ray production cross-sections for Au and Pb in the incident proton energy range between 1 and 2.5 MeV are presented. The experimental results for X-ray production cross-sections are compared to available data given in Sokhi and Crumpton [R.S. Sokhi, D. Crumpton, At. Data Nucl. Data Tables 30 (1984) 49], Jesus et al. [A.P. Jesus, J.S. Lopes, J.P. Ribeiro, J. Phys. B: At. Mol. Phys. 18 (1985) 2456; A.P. Jesus, T.M. Pinheiro, I.A. Nisa, J.P. Ribeiro, J.S. Lopes, Nucl. Instrum. Methods B15 (1986) 95] and Goudarzi et al. [M. Goudarzi, F. Shokouhi, M. Lamehi-Rachti, P.Olialiy, Nucl. Instrum. Methods Phys. Res. B247 (2006) 218]. The given data are also compared with the predictions of ECPSSR model [W. Brandt, G. Lapicki, Phys. Rev. A23 (1981) 1717].

  20. Tables of nuclear cross sections for galactic cosmic rays: Absorption cross sections

    NASA Technical Reports Server (NTRS)

    Townsend, L. W.; Wilson, J. W.

    1985-01-01

    A simple but comprehensive theory of nuclear reactions is presented. Extensive tables of nucleon, deuteron, and heavy-ion absorption cross sections over a broad range of energies are generated for use in cosmic ray shielding studies. Numerous comparisons of the calculated values with available experimental data show agreement to within 3 percent for energies above 80 MeV/nucleon and within approximately 10 percent for energies as low as 30 MeV/nucleon. These tables represent the culmination of the development of the absorption cross section formalism and supersede the preliminary absorption cross sections published previously in NASA TN D-8107, NASA TP-2138, and NASA TM-84636.

  1. Alpha particle induced reactions on natCr up to 39 MeV: Experimental cross-sections, comparison with theoretical calculations and thick target yields for medically relevant 52gFe production

    NASA Astrophysics Data System (ADS)

    Hermanne, A.; Adam Rebeles, R.; Tárkányi, F.; Takács, S.

    2015-08-01

    Thin natCr targets were obtained by electroplating, using 23.75 μm Cu foils as backings. In five stacked foil irradiations, followed by high resolution gamma spectroscopy, the cross sections for production of 52gFe, 49,51cumCr, 52cum,54,56cumMn and 48cumV in Cr and 61Cu,68Ga in Cu were measured up to 39 MeV incident α-particle energy. Reduced uncertainty is obtained by simultaneous remeasurement of the natCu(α,x)67,66Ga monitor reactions over the whole energy range. Comparisons with the scarce literature values and results from the TENDL-2013 on-line library, based on the theoretical code family TALYS-1.6, were made. A discussion of the production routes for 52gFe with achievable yields and contamination rates was made.

  2. Calculating Rayleigh scattering amplitudes from 100 eV to 10 MeV. [100 eV to 10 MeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Parker, J.C.; Reynaud, G.W.; Botto, D.J.

    1979-05-01

    An attempt is made to explain how to calculate the contribution to elastic photon-atom scattering due to Rayleigh scattering (the scattering off bound electrons) in the photon energy range 100 eV less than or equal to W less than or equal to 10 MeV. All intermediate calculations are described, including the calculation of the potential, bound state wave functions, matrix elements, and final cross sections. 12 references. (JFP)

  3. A Temperature-Dependent, Linearly Interpolable, Tabulated Cross Section Library Based on ENDF/B-VI, Release 7.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    CULLEN, D. E.

    2001-06-13

    Version 00 As distributed, the original evaluated data include cross sections represented in the form of a combination of resonance parameters and/or tabulated energy dependent cross sections, nominally at 0 Kelvin temperature. For use in applications, these ENDF/B-VI, Release 7 data were processed into the form of temperature dependent cross sections at eight temperatures between 0 and 2100 Kelvin, in steps of 300 Kelvin. At each temperature the cross sections are tabulated and linearly interpolable in energy. POINT2000 contains all of the evaluations in the ENDF/B-VI general purpose library, which contains evaluations for 324 materials (isotopes or naturally occurring elementalmore » mixtures of isotopes). No special purpose ENDF/B-VI libraries, such as fission products, thermal scattering, photon interaction data are included. The majority of these evaluations are complete, in the sense that they include all cross sections over the energy range 10-5 eV to at least 20 MeV. However, the following are only partial evaluations that either only contain single reactions and no total cross section (Mg24, K41, Ti46, Ti47, Ti48, Ti50 and Ni59), or do not include energy dependent cross sections above the resonance region (Ar40, Mo92, Mo98, Mo100, In115, Sn120, Sn122 and Sn124). The CCC-638/TART96 code package will soon be updated to TART2000, which is recommended for use with these data. Codes within TART2000 can be used to display these data or to run calculations using these data.« less

  4. Total Hadron Cross Section, New Particles, and Muon Electron Events in e{sup +}e{sup -} Annihilation at SPEAR

    DOE R&D Accomplishments Database

    Richter, B.

    1976-01-01

    The review of total hadron electroproduction cross sections, the new states, and the muon--electron events includes large amount of information on hadron structure, nine states with width ranging from 10's of keV to many MeV, the principal decay modes and quantum numbers of some of the states, and limits on charm particle production. 13 references. (JFP)

  5. Benchmark of neutron production cross sections with Monte Carlo codes

    NASA Astrophysics Data System (ADS)

    Tsai, Pi-En; Lai, Bo-Lun; Heilbronn, Lawrence H.; Sheu, Rong-Jiun

    2018-02-01

    Aiming to provide critical information in the fields of heavy ion therapy, radiation shielding in space, and facility design for heavy-ion research accelerators, the physics models in three Monte Carlo simulation codes - PHITS, FLUKA, and MCNP6, were systematically benchmarked with comparisons to fifteen sets of experimental data for neutron production cross sections, which include various combinations of 12C, 20Ne, 40Ar, 84Kr and 132Xe projectiles and natLi, natC, natAl, natCu, and natPb target nuclides at incident energies between 135 MeV/nucleon and 600 MeV/nucleon. For neutron energies above 60% of the specific projectile energy per nucleon, the LAQGMS03.03 in MCNP6, the JQMD/JQMD-2.0 in PHITS, and the RQMD-2.4 in FLUKA all show a better agreement with data in heavy-projectile systems than with light-projectile systems, suggesting that the collective properties of projectile nuclei and nucleon interactions in the nucleus should be considered for light projectiles. For intermediate-energy neutrons whose energies are below the 60% projectile energy per nucleon and above 20 MeV, FLUKA is likely to overestimate the secondary neutron production, while MCNP6 tends towards underestimation. PHITS with JQMD shows a mild tendency for underestimation, but the JQMD-2.0 model with a modified physics description for central collisions generally improves the agreement between data and calculations. For low-energy neutrons (below 20 MeV), which are dominated by the evaporation mechanism, PHITS (which uses GEM linked with JQMD and JQMD-2.0) and FLUKA both tend to overestimate the production cross section, whereas MCNP6 tends to underestimate more systems than to overestimate. For total neutron production cross sections, the trends of the benchmark results over the entire energy range are similar to the trends seen in the dominate energy region. Also, the comparison of GEM coupled with either JQMD or JQMD-2.0 in the PHITS code indicates that the model used to describe the first

  6. Measurement of sigma(e+e- -->psi(3770)-->hadrons) at Ec.m.=3773 MeV.

    PubMed

    Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Gong, D T; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Smith, A; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A; Zweber, P; Ernst, J; Arms, K; Severini, H; Dytman, S A; Love, W; Mehrabyan, S; Mueller, J A; Savinov, V; Li, Z; Lopez, A; Mendez, H; Ramirez, J; Huang, G S; Miller, D H; Pavlunin, V; Sanghi, B; Shipsey, I P J; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Napolitano, J; He, Q; Muramatsu, H; Park, C S; Thorndike, E H; Coan, T E; Gao, Y S; Liu, F; Artuso, M; Boulahouache, C; Blusk, S; Butt, J; Li, J; Menaa, N; Mountain, R; Nisar, S; Randrianarivony, K; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, K; Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Briere, R A; Chen, G P; Chen, J; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L; Adam, N E; Alexander, J P; Berkelman, K; Cassel, D G; Duboscq, J E; Ecklund, K M; Ehrlich, R; Fields, L; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Meyer, T O; Onyisi, P U E; Patterson, J R; Peterson, D; Phillips, E A; Pivarski, J; Riley, D; Ryd, A; Sadoff, A J; Schwarthoff, H; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Patel, R; Potlia, V; Stoeck, H; Yelton, J; Rubin, P; Cawlfield, C; Eisenstein, B I; Karliner, I; Kim, D; Lowrey, N; Naik, P; Sedlack, C; Selen, M; White, E J; Wiss, J; Shepherd, M R; Asner, D M; Edwards, K W

    2006-03-10

    We measure the cross section for e+e- -->psi(3770) -->hadrons at Ec.m.=3773 MeV to be (6.38+/-0.08(+0.41)(-0.30) nb using the CLEO detector at the CESR e+e- collider. The difference between this and the e+e- -->psi(3770) -->DD cross section at the same energy is found to be (-0.01+/-0.08(+0.41)(-0.30) nb. With the observed total cross section, we extract Gamma(ee)(psi(3770))=(0.204+/-0.003(+0.041)(-0.027) keV. Uncertainties shown are statistical and systematic, respectively.

  7. Neutron Scattering Differential Cross Sections for 12C

    NASA Astrophysics Data System (ADS)

    Byrd, Stephen T.; Hicks, S. F.; Nickel, M. T.; Block, S. G.; Peters, E. E.; Ramirez, A. P. D.; Mukhopadhyay, S.; McEllistrem, M. T.; Yates, S. W.; Vanhoy, J. R.

    2016-09-01

    Because of the prevalence of its use in the nuclear energy industry and for our overall understanding of the interactions of neutrons with matter, accurately determining the effects of fast neutrons scattering from 12C is important. Previously measured 12C inelastic neutron scattering differential cross sections found in the National Nuclear Data Center (NNDC) show significant discrepancies (>30%). Seeking to resolve these discrepancies, neutron inelastic and elastic scattering differential cross sections for 12C were measured at the University of Kentucky Acceleratory Laboratory for incident neutron energies of 5.58, 5.83, and 6.04 MeV. Quasi mono-energetic neutrons were scattered off an enriched 12C target (>99.99%) and detected by a C6D6 liquid scintillation detector. Time-of-flight (TOF) techniques were used to determine scattered neutron energies and allowed for elastic/inelastic scattering distinction. Relative detector efficiencies were determined through direct measurements of neutrons produced by the 2H(d,n) and 3H(p,n) source reactions, and absolute normalization factors were found by comparing 1H scattering measurements to accepted NNDC values. This experimental procedure has been successfully used for prior neutron scattering measurements and seems well-suited to our current objective. Significant challenges were encountered, however, with measuring the neutron detector efficiency over the broad incident neutron energy range required for these measurements. Funding for this research was provided by the National Nuclear Security Administration (NNSA).

  8. Cross section measurements for neutron inelastic scattering and the ( n ,   2 n γ ) reaction on Pb 206

    DOE PAGES

    Negret, A.; Mihailescu, L. C.; Borcea, C.; ...

    2015-06-30

    We measured excitation functions for γ production associated with the neutron inelastic scattering and the (n, 2n) reactions on 206Pb from threshold up to 18 MeV for about 40 transitions. Two independent measurements were performed using different samples and acquisition systems to check consistency of the results. Moreover, the neutron flux was determined with a 235U fission chamber and a procedure that were validated against a fluence standard. For incident energy higher than the threshold for the first excited level and up to 3.5 MeV, estimates are provided for the total inelastic and level cross sections by combining the presentmore » γ production cross sections with the level and decay data of 206Pb reported in the literature. The uncertainty common to all incident energies is 3.0% allowing overall uncertainties from 3.3% to 30% depending on transition and neutron energy. Finally, the present data agree well with earlier work, but significantly expand the experimental database while comparisons with model calculations using the talys reaction code show good agreement over the full energy range.« less

  9. Cross-section measurements of the 86Kr(γ,n) reaction to probe the s-process branching at 85Kr.

    PubMed

    Raut, R; Tonchev, A P; Rusev, G; Tornow, W; Iliadis, C; Lugaro, M; Buntain, J; Goriely, S; Kelley, J H; Schwengner, R; Banu, A; Tsoneva, N

    2013-09-13

    We have carried out photodisintegration cross-section measurements on 86Kr using monoenergetic photon beams ranging from the neutron separation energy, S(n) = 9.86  MeV, to 13 MeV. We combine our experimental 86Kr(γ,n)85Kr cross section with results from our recent 86Kr(γ,γ') measurement below the neutron separation energy to obtain the complete nuclear dipole response of 86Kr. The new experimental information is used to predict the neutron capture cross section of 85Kr, an important branching point nucleus on the abundance flow path during s-process nucleosynthesis. Our new and more precise 85Kr(n,γ)86Kr cross section allows us to produce more precise predictions of the 86Kr abundance from s-process models. In particular, we find that the models of the s process in asymptotic giant branch stars of mass <1.5M⊙, where the 13C neutron source burns convectively rather than radiatively, represent a possible solution for the highest 86Kr:82Kr ratios observed in meteoritic stardust SiC grains.

  10. The 200 MeV Pi+ induced single-nucleon removal from 24Mg

    NASA Technical Reports Server (NTRS)

    Joyce, Donald; Lieb, B. Joseph; Lieb, B. Joseph; Lieb, B. Joseph; Lieb, B. Joseph; Lieb, B. Joseph; Lieb, B. Joseph; Lieb, B. Joseph; Lieb, B. Joseph; Lieb, B. Joseph; hide

    1985-01-01

    Nuclear gamma-rays in coincidence with outgoing pions or protons following single nucleon removal from Mg-24 by 200 MeV pions (+) were detected with Ge(Li) detectors. Differential cross sections are reported for gamma-rays from the first excited mirror states of Na-23 and Mg-23 in coincidence with positive pions or protons detected in particle telescopes at 30, 60, 90, 120, and 150 deg; angle-integrated absolute cross sections and cross section ratios are calculated. These results are compared with the predictions of a Pauli-blocked plane-wave impulse approximation (PWIA) and the intranuclear cascade (INC) and nucleon charge exchange (NCX) reaction models. The PWIA and the INC calculations generally agree with the angular dependence of the experimental results but not the absolute magnitude. The NCX calculation does not reproduce the observed cross section charge ratios.

  11. Cross section of α-induced reactions on iridium isotopes obtained from thick target yield measurement for the astrophysical γ process

    NASA Astrophysics Data System (ADS)

    Szücs, T.; Kiss, G. G.; Gyürky, Gy.; Halász, Z.; Fülöp, Zs.; Rauscher, T.

    2018-01-01

    The stellar reaction rates of radiative α-capture reactions on heavy isotopes are of crucial importance for the γ process network calculations. These rates are usually derived from statistical model calculations, which need to be validated, but the experimental database is very scarce. This paper presents the results of α-induced reaction cross section measurements on iridium isotopes carried out at first close to the astrophysically relevant energy region. Thick target yields of 191Ir(α,γ)195Au, 191Ir(α,n)194Au, 193Ir(α,n)196mAu, 193Ir(α,n)196Au reactions have been measured with the activation technique between Eα = 13.4 MeV and 17 MeV. For the first time the thick target yield was determined with X-ray counting. This led to a previously unprecedented sensitivity. From the measured thick target yields, reaction cross sections are derived and compared with statistical model calculations. The recently suggested energy-dependent modification of the α + nucleus optical potential gives a good description of the experimental data.

  12. Annular-Cross-Section CFE Chamber

    NASA Technical Reports Server (NTRS)

    Sharnez, Rizwan; Sammons, David W.

    1994-01-01

    Proposed continuous-flow-electrophoresis (CFE) chamber of annular cross section offers advantages over conventional CFE chamber, and wedge-cross-section chamber described in "Increasing Sensitivity in Continuous-Flow Electrophoresis" (MFS-26176). In comparison with wedge-shaped chamber, chamber of annular cross section virtually eliminates such wall effects as electro-osmosis and transverse gradients of velocity. Sensitivity enhanced by incorporating gradient maker and radial (collateral) flow.

  13. Measurement of the 169Tm(n,3n) 167Tm cross section and the associated branching ratios in the decay of 167Tm [Measurement of the 169Tm(n,3n) 167Tm cross section and the branching ratios in the decay of 167Tm

    DOE PAGES

    Champine, B.; Gooden, M. E.; Krishichayan, .; ...

    2016-01-14

    The cross section for the 169Tm(n,3n) 167Tm reaction was measured from 17 to 22 MeV using quasimonoenergetic neutrons produced by the 2H(d,n) 3He reaction. This energy range was studied to resolve the discrepancy between previous (n,3n) cross-section measurements. In addition, the absolute γ-ray branching ratios following the electron-capture decay of 167Tm were measured. Furthermore, these results provide more reliable nuclear data for an important diagnostic that is used at the National Ignition Facility to estimate the yield of reaction-in-flight neutrons produced via the inertial-confinement-fusion plasma in deuterium-tritium capsules.

  14. Measurement of the beryllium-7 plus proton fusion cross section

    NASA Astrophysics Data System (ADS)

    Fitzgerald, Ryan P.

    2005-11-01

    The fusion of protons with radioactive nuclei plays an important role in a wide variety of astrophysical scenarios ranging from high-temperature environments like novae and X-ray bursts to the production of neutrinos in the sun. For example, the 8 B neutrino flux measured in neutrino detectors on earth is directly proportional to the cross section for the fusion of protons with radioactive 7 Be. An experimental program has been established to study proton-fusion experiments in inverse kinematics at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory (ORNL) using a windowless gas target and the Daresbury Recoil Separator (DRS). The performance of the target and separator have been well characterized using a variety of experiments with stable beams including 12 C, 19 F, and 24 Mg. For instance, the areal density of hydrogen in the target was determined to 3% accuracy. This well-characterized system was used to measure accurate stopping powers for many elements in hydrogen gas for the first time. The first measurement of a proton-fusion cross section with a radioactive ion beam at ORNL, the fusion of protons with 7 Be, was performed using the hydrogen gas target and the DRS. The 7 Be was produced at the Triangle Universities Nuclear Laboratory (TUNL) and chemically isolated at ORNL. An average 7 Be beam current of 2.5 ppA bombarded the windowless gas target for a period of 3 days. Recoiling B-8 nuclei were efficiently collected using the DRS and were clearly identified in a gas-filled ion detector. The cross section at a center-of-mass energy of 1.502 MeV was determined to be 1.12 mb with 24% uncertainty. The zero-energy S-factor was determined to be 26.8 eV-b with 25% uncertainty. The technique has been clearly demonstrated, and a precise measurement of the fusion cross section will be possible with the development of a somewhat more intense 7 Be radioactive ion beam.

  15. 239Pu(n,γ) from 10 eV to 1.3 MeV

    NASA Astrophysics Data System (ADS)

    Mosby, S.; Bredeweg, T. A.; Couture, A.; Jandel, M.; Kawano, T.; Ullmann, J.; Henderson, R. A.; Wu, C. Y.

    2018-02-01

    The 239Pu(n,γ) cross section has been measured from 10 eV to 1.3 MeV as part of an experimental campaign using the Detector for Advanced Neutron Capture Experiments (DANCE). The work represents a significant advance in experimental technique, with improved systematic uncertainties in key regions in the keV to MeV regime. In general the results of prior work are confirmed with improved uncertainties, particularly at the highest incident neutron energies.

  16. Kuang's Semi-Classical Formalism for Calculating Electron Capture Cross Sections: A Space- Physics Application

    NASA Technical Reports Server (NTRS)

    Barghouty, A. F.

    2014-01-01

    Accurate estimates of electroncapture cross sections at energies relevant to the modeling of the transport, acceleration, and interaction of energetic neutral atoms (ENA) in space (approximately few MeV per nucleon) and especially for multi-electron ions must rely on detailed, but computationally expensive, quantum-mechanical description of the collision process. Kuang's semi-classical approach is an elegant and efficient way to arrive at these estimates. Motivated by ENA modeling efforts for apace applications, we shall briefly present this approach along with sample applications and report on current progress.

  17. Vertically stabilized elongated cross-section tokamak

    DOEpatents

    Sheffield, George V.

    1977-01-01

    This invention provides a vertically stabilized, non-circular (minor) cross-section, toroidal plasma column characterized by an external separatrix. To this end, a specific poloidal coil means is added outside a toroidal plasma column containing an endless plasma current in a tokamak to produce a rectangular cross-section plasma column along the equilibrium axis of the plasma column. By elongating the spacing between the poloidal coil means the plasma cross-section is vertically elongated, while maintaining vertical stability, efficiently to increase the poloidal flux in linear proportion to the plasma cross-section height to achieve a much greater plasma volume than could be achieved with the heretofore known round cross-section plasma columns. Also, vertical stability is enhanced over an elliptical cross-section plasma column, and poloidal magnetic divertors are achieved.

  18. Gamma rays from the de-excitation of C-12 resonance 15.11 MeV and C-12 resonance 4.44 MeV as probes of energetic particle spectra

    NASA Technical Reports Server (NTRS)

    Crannell, C. J.; Crannell, H.; Ramaty, R.

    1977-01-01

    The flux of 15.11 MeV gamma rays relative to the flux 4.44 MeV gamma rays was calculated from measured cross sections for excitation of the corresponding states of C-12 and from experimental determinations of the branching ratios for direct de-excitation of these states to the ground state. Because of the difference in threshold energies for excitation of these two levels, the relative intensities in the two lines are particularly sensitive to the spectral distribution of energetic particles which excite the corresponding nuclear levels. For both solar and cosmic emission, the observability of the 15.11 MeV line is expected to be enhances by low source-background continuum in this energy range.

  19. Energy dependence of the ratio of isovector effective interaction strengths |JστJτ| from 0° (p,n) cross sections

    NASA Astrophysics Data System (ADS)

    Taddeucci, T. N.; Rapaport, J.; Bainum, D. E.; Goodman, C. D.; Foster, C. C.; Gaarde, C.; Larsen, J.; Goulding, C. A.; Horen, D. J.; Masterson, T.; Sugarbaker, E.

    1982-02-01

    Information concerning the ratio of the isovector effective interaction strengths |JστJτ| may be obtained from the ratio of (p,n) Gamow-Teller and isobaric analog state 0° differential cross sections. We have examined 0° (p,n) data for the energy range 5-200 MeV and find that for energies larger than 50 MeV and for targets with A=7-42 the product of the interaction-strength and distortion-factor ratios |JστJτ|(NστNτ)12 appears to be mass independent and linear as a function of bombarding energy. NUCLEAR REACTIONS 7Li, 13, 14C, 26Mg, 37Cl, 41Ca(p,n), measured σ(θ=0°), GT, IAS transitions, Ep=60-200 MeV. Deduced energy dependence, interaction strength ratio |JστJτ|.

  20. Comprehensive sets of 124Xe(n ,γ )125Xe and 124Xe(n ,2 n )123Xe cross-section data for assessment of inertial-confinement deuterium-tritium fusion plasma

    NASA Astrophysics Data System (ADS)

    Bhike, Megha; Fallin, B.; Gooden, M. E.; Ludin, N.; Tornow, W.

    2015-01-01

    Measurements of the neutron radiative-capture cross section of 124Xe have been performed for the first time for neutron energies above 100 keV. In addition, data for the 124Xe(n ,2 n )123Xe reaction cross section have been obtained from threshold to 14.8 MeV to cover the entire energy range of interest, while previous data existed only at around 14 MeV. The results of these measurements provide the basis for an alternative and sensitive diagnostic tool for investigating properties of the inertial confinement fusion plasma in deuterium-tritium (DT) capsules at the National Ignition Facility located at Lawrence Livermore National Laboratory. Here, areal density ρ R (density × radius) of the fuel, burn asymmetry, and fuel-ablator mix are of special interest. The 124Xe(n ,γ )125Xe reaction probes the down-scattered neutrons, while the 124Xe(n ,2 n )123Xe reaction provides a measure of the 14 MeV direct neutrons.

  1. Measurement of the 234U(n, f ) cross-section with quasi-monoenergetic beams in the keV and MeV range using a Micromegas detector assembly

    NASA Astrophysics Data System (ADS)

    Stamatopoulos, A.; Kanellakopoulos, A.; Kalamara, A.; Diakaki, M.; Tsinganis, A.; Kokkoris, M.; Michalopoulou, V.; Axiotis, M.; Lagoyiannis, A.; Vlastou, R.

    2018-01-01

    The 234U neutron-induced fission cross-section has been measured at incident neutron energies of 452, 550, 651 keV and 7.5, 8.7, 10 MeV using the 7Li ( p, n) and the 2H( d, n) reactions, respectively, relative to the 235U( n, f ) and 238U( n, f ) reference reactions. The measurement was performed at the neutron beam facility of the National Center for Scientific Research "Demokritos", using a set-up based on Micromegas detectors. The active mass of the actinide samples and the corresponding impurities were determined via α-spectroscopy using a surface barrier silicon detector. The neutron spectra intercepted by the actinide samples have been thoroughly studied by coupling the NeuSDesc and MCNP5 codes, taking into account the energy and angular straggling of the primary ion beams in the neutron source targets in addition to contributions from competing reactions ( e.g. deuteron break-up) and neutron scattering in the surrounding materials. Auxiliary Monte Carlo simulations were performed making combined use of the FLUKA and GEF codes, focusing particularly on the determination of the fission fragment detection efficiency. The developed methodology and the final results are presented.

  2. Measurement of the absolute differential cross section of proton–proton elastic scattering at small angles

    DOE PAGES

    Mchedlishvili, D.; Chiladze, D.; Dymov, S.; ...

    2016-02-03

    The differential cross section for proton-proton elastic scattering has been measured at a beam kinetic energy of 1.0 GeV and in 200 MeV steps from 1.6 to 2.8 GeV for centre-of-mass angles in the range from 12°-16° to 25°-30°, depending on the energy. A precision in the overall normalisation of typically 3% was achieved by studying the energy losses of the circulating beam of the COSY storage ring as it passed repeatedly through the windowless hydrogen target of the ANKE magnetic spectrometer. It is shown that the data have a significant impact upon the results of a partial wave analysis.more » Furthermore, after extrapolating the differential cross sections to the forward direction, the results are broadly compatible with the predictions of forward dispersion relations.« less

  3. A possible approach to 14MeV neutron moderation: A preliminary study case.

    PubMed

    Flammini, D; Pilotti, R; Pietropaolo, A

    2017-07-01

    Deuterium-Tritium (D-T) interactions produce almost monochromatic neutrons with about 14MeV energy. These neutrons are used in benchmark experiments as well as for neutron cross sections assessment in fusion reactors technology. The possibility to moderate 14MeV neutrons for purposes beyond fusion is worth to be studied in relation to projects of intense D-T sources. In this preliminary study, carried out using the MCNP Monte Carlo code, the moderation of 14MeV neutrons is approached foreseeing the use of combination of metallic materials as pre-moderator and reflectors coupled to standard water moderators. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. {sup 110,116}Cd({alpha},{alpha}){sup 110,116}Cd elastic scattering and systematic investigation of elastic {alpha} scattering cross sections along the Z=48 isotopic and N=62 isotonic chains

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kiss, G. G.; Fueloep, Zs.; Gyuerky, Gy.

    2011-06-15

    The elastic scattering cross sections for the reactions {sup 110,116}Cd({alpha},{alpha}){sup 110,116}Cd at energies above and below the Coulomb barrier are presented to provide a sensitive test for the {alpha}-nucleus optical potential parameter sets. Additional constraints for the optical potential are taken from the analysis of elastic scattering excitation functions at backward angles which are available in literature. Moreover, the variation of the elastic {alpha} scattering cross sections along the Z=48 isotopic and N=62 isotonic chain is investigated by the study of the ratios of the {sup 106,110,116}Cd({alpha},{alpha}){sup 106,110,116}Cd scattering cross sections at E{sub cm{approx_equal}}15.6and18.8 MeV and the ratio of themore » {sup 110}Cd({alpha},{alpha}){sup 110}Cd and {sup 112}Sn({alpha},{alpha}){sup 112}Sn reaction cross sections at E{sub cm{approx_equal}}18.8 MeV, respectively. These ratios are sensitive probes for the {alpha}-nucleus optical potential parametrizations. The potentials under study are a basic prerequisite for the prediction of {alpha}-induced reaction cross sections (e.g., for the calculation of stellar reaction rates in the astrophysical p or {gamma} process).« less

  5. HIGH PRECISION K-SHELL PHOTOABSORPTION CROSS SECTIONS FOR ATOMIC OXYGEN: EXPERIMENT AND THEORY

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McLaughlin, B. M.; Ballance, C. P.; Bowen, K. P.

    2013-07-01

    Photoabsorption of atomic oxygen in the energy region below the 1s {sup -1} threshold in X-ray spectroscopy from Chandra and XMM-Newton is observed in a variety of X-ray binary spectra. Photoabsorption cross sections determined from an R-matrix method with pseudo-states and new, high precision measurements from the Advanced Light Source (ALS) are presented. High-resolution spectroscopy with E/{Delta}E Almost-Equal-To 4250 {+-} 400 was obtained for photon energies from 520 eV to 555 eV at an energy resolution of 124 {+-} 12 meV FWHM. K-shell photoabsorption cross section measurements were made with a re-analysis of previous experimental data on atomic oxygen atmore » the ALS. Natural line widths {Gamma} are extracted for the 1s {sup -1}2s {sup 2}2p {sup 4}({sup 4} P)np {sup 3} P Degree-Sign and 1s {sup -1}2s {sup 2}2p {sup 4}({sup 2} P)np {sup 3} P Degree-Sign Rydberg resonances series and compared with theoretical predictions. Accurate cross sections and line widths are obtained for applications in X-ray astronomy. Excellent agreement between theory and the ALS measurements is shown which will have profound implications for the modeling of X-ray spectra and spectral diagnostics.« less

  6. 239Pu(n,γ) from 10 eV to 1.3 MeV

    DOE PAGES

    Mosby, Shea Morgan; Bredeweg, Todd Allen; Couture, Aaron Joseph; ...

    2018-02-01

    In this study, the 239Pu(n,γ) cross section has been measured from 10 eV to 1.3 MeV as part of an experimental campaign using the Detector for Advanced Neutron Capture Experiments (DANCE). The work represents a significant advance in experimental technique, with improved systematic uncertainties in key regions in the keV to MeV regime. In general the results of prior work are confirmed with improved uncertainties, particularly at the highest incident neutron energies.

  7. Measurements of 89Y(n,2n)88Y and 89Y(n,3n)87Y, 87mY cross sections for fast neutrons at KIRAMS

    NASA Astrophysics Data System (ADS)

    In, Eun Jin; Bak, Sang-In; Ham, Cheolmin; Kim, Do Yoon; Myung, Hyunjeong; Shim, Chungbo; Shin, Jae Won; Min, Kyung Joo; Zhou, Yujie; Park, Tae-Sun; Hong, Seung-Woo; Bhoraskar, V. N.

    2017-09-01

    A proton cyclotron MC-50 in Korea Institute of Radiological & Medical Science (KIRAMS) is used to carry out neutron activation experiments with Y2O3 targets irradiated with neutron beams of a continuous spectrum produced by proton beams on a thick beryllium target. Neutrons are generated by 9Be (p, n) reaction with an incident proton intensity of 20 μA. The neutron spectra generated by proton beams of 30, 35, and 40 MeV are calculated by GEANT4 simulations. Nb powders are used for neutron flux monitoring by measuring the activities of 92mNb through the reaction 93Nb (n, 2n). By using a subtraction method, the average cross section of 89Y(n,2n) and 89Y(n,3n) reactions at the neutron energies of 29.8 ± 1.8 MeV and 34.8 ± 1.8 MeV are extracted and are found to be close to the existing cross sections from the EXFOR data and the evaluated nuclear data libraries such as TENDL-2015 or EAF-2010.

  8. Nuclear Forensics and Radiochemistry: Cross Sections

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rundberg, Robert S.

    The neutron activation of components in a nuclear device can provide useful signatures of weapon design or sophistication. This lecture will cover some of the basics of neutron reaction cross sections. Nuclear reactor cross sections will also be presented to illustrate the complexity of convolving neutron energy spectra with nuclear excitation functions to calculate useful effective reactor cross sections. Deficiencies in the nuclear database will be discussed along with tools available at Los Alamos to provide new neutron cross section data.

  9. Total cross sections for positrons scattered elastically from helium based on new measurements of total ionization cross sections

    NASA Technical Reports Server (NTRS)

    Diana, L. M.; Chaplin, R. L.; Brooks, D. L.; Adams, J. T.; Reyna, L. K.

    1990-01-01

    An improved technique is presented for employing the 2.3m spectrometer to measure total ionization cross sections, Q sub ion, for positrons incident on He. The new ionization cross section agree with the values reported earlier. Estimates are also presented of total elastic scattering cross section, Q sub el, obtained by subtracting from total scattering cross sections, Q sub tot, reported in the literature, the Q sub ion and Q sub Ps (total positronium formation cross sections) and total excitation cross sections, Q sub ex, published by another researcher. The Q sub ion and Q sub el measured with the 3m high resolution time-of-flight spectrometer for 54.9eV positrons are in accord with the results from the 2.3m spectrometer. The ionization cross sections are in fair agreement with theory tending for the most part to be higher, especially at 76.3 and 88.5eV. The elastic cross section agree quite well with theory to the vicinity of 50eV, but at 60eV and above the experimental elastic cross sections climb to and remain at about 0.30 pi a sub o sq while the theoretical values steadily decrease.

  10. Reducing cross-sectional data using a genetic algorithm method and effects on cross-section geometry and steady-flow profiles

    USGS Publications Warehouse

    Berenbrock, Charles E.

    2015-01-01

    The effects of reduced cross-sectional data points on steady-flow profiles were also determined. Thirty-five cross sections of the original steady-flow model of the Kootenai River were used. These two methods were tested for all cross sections with each cross section resolution reduced to 10, 20 and 30 data points, that is, six tests were completed for each of the thirty-five cross sections. Generally, differences from the original water-surface elevation were smaller as the number of data points in reduced cross sections increased, but this was not always the case, especially in the braided reach. Differences were smaller for reduced cross sections developed by the genetic algorithm method than the standard algorithm method.

  11. Femtosecond time-resolved MeV electron diffraction

    DOE PAGES

    Zhu, Pengfei; Zhu, Y.; Hidaka, Y.; ...

    2015-06-02

    We report the experimental demonstration of femtosecond electron diffraction using high-brightness MeV electron beams. High-quality, single-shot electron diffraction patterns for both polycrystalline aluminum and single-crystal 1T-TaS 2 are obtained utilizing a 5 fC (~3 × 10 4 electrons) pulse of electrons at 2.8 MeV. The high quality of the electron diffraction patterns confirms that electron beam has a normalized emittance of ~50 nm rad. The transverse and longitudinal coherence length is ~11 and ~2.5 nm, respectively. The timing jitter between the pump laser and probe electron beam was found to be ~100 fs (rms). The temporal resolution is demonstrated bymore » observing the evolution of Bragg and superlattice peaks of 1T-TaS 2 following an 800 nm optical pump and was found to be 130 fs. Lastly, our results demonstrate the advantages of MeV electrons, including large elastic differential scattering cross-section and access to high-order reflections, and the feasibility of ultimately realizing below 10 fs time-resolved electron diffraction.« less

  12. Nucleon-Nucleon Total Cross Section

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    2008-01-01

    The total proton-proton and neutron-proton cross sections currently used in the transport code HZETRN show significant disagreement with experiment in the GeV and EeV energy ranges. The GeV range is near the region of maximum cosmic ray intensity. It is therefore important to correct these cross sections, so that predictions of space radiation environments will be accurate. Parameterizations of nucleon-nucleon total cross sections are developed which are accurate over the entire energy range of the cosmic ray spectrum.

  13. Inelastic scattering of 61 MeV protons by pb-207

    NASA Technical Reports Server (NTRS)

    Owais, M.

    1976-01-01

    Differential cross sections for the excitation of the first four neutron-hole states and the doublet at 2.61 MeV by 61.2 MeV protons were measured. The data are analyzed in terms of both a purely collective model description and a microscopic model supplemented by macroscopic core polarization. A realistic two-body interaction is used and knock-on amplitudes are included. Core polarization is found to be important but represents a relatively smaller contribution than in most nuclei previously studied. A parallel analysis of similar data at lower proton bombarding energies reveals a surprisingly strong energy dependence of the reaction mechanisms.

  14. Exclusive measurements of light fragment production at forward angles in NePb and NeNaF collisions at {E}/{A} = 400 MeV and 800 MeV

    NASA Astrophysics Data System (ADS)

    Bastid, N.; Alard, J. P.; Arnold, J.; Augerat, J.; Babinet, R.; Biagi, F.; Brochard, F.; Crouau, M.; Charmensat, P.; Dupieux, P.; Fodor, Z.; Fraysse, L.; Girard, J.; Gorodetzky, P.; Gosset, J.; Laspalles, C.; Lemaire, M. C.; Le Merdy, A.; L'hôte, D.; Lucas, B.; Marroncle, J.; Montarou, G.; Parizet, M. J.; Poitou, J.; Qassoud, D.; Racca, C.; Rahmani, A.; Schimmerling, W.; Terrien, Y.; Valette, O.

    1990-01-01

    Emission of light fragments at small angles is studied in relativistic heavy ion collisions using the Diogene plastic wall for both symmetrical and non-symmetrical target-projectile systems with 400 MeV per nucleon and 800 MeV per nucleon incident neon nuclei. Efficiency of multiplicity measurements in the small angle range for the selection of central or peripheral collisions is confirmed for asymmetric systems. Differential production cross sections of Z = 1 fragments show evidence for the existence of two emitting sources. The apparent temperature of each source is obtained from comparison with a thermodynamical model.

  15. Exclusive measurements of light fragment production at forward angles in Ne-Pb and Ne-NaF collisions at E/A=400 MeV and 800 MeV

    NASA Technical Reports Server (NTRS)

    Bastid, N.; Alard, J. P.; Arnold, J.; Augerat, J.; Babinet, R.; Biagi, F.; Brochard, F.; Crouau, M.; Charmensat, P.; Dupieux, P.; hide

    1990-01-01

    Emission of light fragments at small angles is studied in relativistic heavy ion collisions using the Diogene plastic wall for both symmetrical and non-symmetrical target-projectile systems with 400 MeV per nucleon and 800 MeV per nucleon incident neon nuclei. Efficiency of multiplicity measurements in the small angle range for the selection of central or peripheral collisions is confirmed for asymmetric systems. Differential production cross sections of Z = 1 fragments show evidence for the existence of two emitting sources. The apparent temperature of each source is obtained from comparison with a thermodynamical model.

  16. On the effect of updated MCNP photon cross section data on the simulated response of the HPA TLD.

    PubMed

    Eakins, Jonathan

    2009-02-01

    The relative response of the new Health Protection Agency thermoluminescence dosimeter (TLD) has been calculated for Narrow Series X-ray distribution and (137)Cs photon sources using the Monte Carlo code MCNP5, and the results compared with those obtained during its design stage using the predecessor code, MCNP4c2. The results agreed at intermediate energies (approximately 0.1 MeV to (137)Cs), but differed at low energies (<0.1 MeV) by up to approximately 10%. This disparity has been ascribed to differences in the default photon interaction data used by the two codes, and derives ultimately from the effect on absorbed dose of the recent updates to the photoelectric cross sections. The sources of these data have been reviewed.

  17. Time-Reversal Measurement of the p -Wave Cross Sections of the 7Be (n ,α )4He Reaction for the Cosmological Li Problem

    NASA Astrophysics Data System (ADS)

    Kawabata, T.; Fujikawa, Y.; Furuno, T.; Goto, T.; Hashimoto, T.; Ichikawa, M.; Itoh, M.; Iwasa, N.; Kanada-En'yo, Y.; Koshikawa, A.; Kubono, S.; Miyawaki, E.; Mizuno, M.; Mizutani, K.; Morimoto, T.; Murata, M.; Nanamura, T.; Nishimura, S.; Okamoto, S.; Sakaguchi, Y.; Sakata, I.; Sakaue, A.; Sawada, R.; Shikata, Y.; Takahashi, Y.; Takechi, D.; Takeda, T.; Takimoto, C.; Tsumura, M.; Watanabe, K.; Yoshida, S.

    2017-02-01

    The cross sections of the 7Be (n ,α )4He reaction for p -wave neutrons were experimentally determined at Ec .m .=0.20 - 0.81 MeV slightly above the big bang nucleosynthesis (BBN) energy window for the first time on the basis of the detailed balance principle by measuring the time-reverse reaction. The obtained cross sections are much larger than the cross sections for s -wave neutrons inferred from the recent measurement at the n_TOF facility in CERN, but significantly smaller than the theoretical estimation widely used in the BBN calculations. The present results suggest the 7Be (n ,α )4He reaction rate is not large enough to solve the cosmological lithium problem, and this conclusion agrees with the recent result from the direct measurement of the s -wave cross sections using a low-energy neutron beam and the evaluated nuclear data library ENDF/B-VII.1.

  18. Grazing Incidence Cross-Sectioning of Thin-Film Solar Cells via Cryogenic Focused Ion Beam: A Case Study on CIGSe

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sardashti, Kasra; Haight, Richard; Anderson, Ryan

    2016-06-22

    Cryogenic focused ion beam (Cryo-FIB) milling at near-grazing angles is employed to fabricate cross-sections on thin Cu(In,Ga)Se2 with >8x expansion in thickness. Kelvin probe force microscopy (KPFM) on sloped cross sections showed reduction in grain boundaries potential deeper into the film. Cryo Fib-KPFM enabled the first determination of the electronic structure of the Mo/CIGSe back contact, where a sub 100 nm thick MoSey assists hole extraction due to 45 meV higher work function. This demonstrates that CryoFIB-KPFM combination can reveal new targets of opportunity for improvement in thin-films photovoltaics such as high-work-function contacts to facilitate hole extraction through the backmore » interface of CIGS.« less

  19. Radiolysis of astrophysical ices by heavy ion irradiation: Destruction cross section measurement

    NASA Astrophysics Data System (ADS)

    de Barros, A. L. F.; Boduch, P.; Domaracka, A.; Rothard, H.; da Silveira, E. F.

    2012-08-01

    Many solar system objects, such as planets and their satellites, dust grains in rings, and comets, are known to either be made of ices or to have icy surfaces. These ices are exposed to ionizing radiation including keV, MeV and GeV ions from solar wind or cosmic rays. Moreover, icy dust grains are present in interstellar space and, in particular, in dense molecular clouds. Radiation effects include radiolysis (the destruction of molecules leading to formation of radicals), the formation of new molecules following radiolysis, the desorption or sputtering of atoms or molecules from the surface, compaction of porous ices, and phase changes. This review discusses the application of infrared spectroscopy FTIR to study the evolution of the chemical composition of ices containing the most abundant molecular species found in the solar system and interstellar medium, such as H2O, CO, CO2 and hydrocarbons. We focus on the evolution of chemical composition with ion fluence in order to deduce the corresponding destruction and formation cross sections. Although initial approach focused on product identification, it became increasingly necessary to work toward a comprehensive understanding of ice chemistry. The abundances of these molecules in different phases of ice mantles provide important clues to the chemical processes in dense interstellar clouds, and therefore it is of importance to accurately measure the quantities such as dissociation and formation cross sections of the infrared features of these molecules. We also are able to obtain the scaling of these cross sections with deposited energy.

  20. Direct measurement of nuclear cross-section of astrophysical interest: Results and perspectives

    NASA Astrophysics Data System (ADS)

    Cavanna, Francesca; Prati, Paolo

    2018-03-01

    Stellar evolution and nucleosynthesis are interconnected by a wide network of nuclear reactions: the study of such connection is usually known as nuclear astrophysics. The main task of this discipline is the determination of nuclear cross-section and hence of the reaction rate in different scenarios, i.e. from the synthesis of a few very light isotopes just after the Big Bang to the heavy element production in the violent explosive end of massive stars. The experimental determination of reaction cross-section at the astrophysical relevant energies is extremely difficult, sometime impossible, due to the Coulomb repulsion between the interacting nuclei which turns out in cross-section values down to the fbar level. To overcome these obstacles, several experimental approaches have been developed and the adopted techniques can be roughly divided into two categories, i.e. direct and indirect methods. In this review paper, the general problem of nuclear astrophysics is introduced and discussed from the point of view of experimental approach. We focus on direct methods and in particular on the features of low-background experiments performed at underground laboratory facilities. The present knowledge of reactions involved in the Big Bang and stellar hydrogen-burning scenarios is discussed as well as the ongoing projects aiming to investigate mainly the helium- and carbon-burning phases. Worldwide, a new generation of experiment in the MeV range is in the design phase or at the very first steps and decisive progresses are expected to come in the next years.

  1. Electron ionization cross-section calculations for liquid water at high impact energies

    NASA Astrophysics Data System (ADS)

    Bousis, C.; Emfietzoglou, D.; Hadjidoukas, P.; Nikjoo, H.; Pathak, A.

    2008-04-01

    Cross-sections for the ionization of liquid water is perhaps the most essential set of data needed for modeling electron transport in biological matter. The complexity of ab initio calculations for any multi-electron target has led to largely heuristic semi-empirical models which take advantage elements of the Bethe, dielectric and binary collision theories. In this work we present various theoretical models for calculating total ionization cross-sections (TICSs) for liquid water over the 10 keV-1 MeV electron energy range. In particular, we extend our recent dielectric model calculations for liquid water to relativistic energies using both the appropriate kinematic corrections and the transverse part. Comparisons are made with widely used atomic and molecular TICS models such as those of Khare and co-workers, Kim-Rudd, Deutsch-Märk, Vriens and Gryzinski. The required dipole oscillator strength was provided by our recent optical-data model which is based on the latest experimental data for liquid water. The TICSs computed by the above models differ by up to 40% from the dielectric results. The best agreement (to within ∼10%) was obtained by Khare's original model and an approximate form of Gryzinski's model. In contrast, the binary-encounter-dipole (BED) models of both Kim-Rudd and Khare and co-workers resulted in ∼10-20% higher TICS values, while discrepancies increased to ∼30-40% when their simpler binary-encounter-Bethe (BEB) versions were used. Finally, we discuss to what extent the accuracy of the TICS is indicative of the reliability of the underlying differential cross-sections.

  2. Statistical γ -decay properties of 64Ni and deduced (n ,γ ) cross section of the s -process branch-point nucleus 63Ni

    NASA Astrophysics Data System (ADS)

    Crespo Campo, L.; Bello Garrote, F. L.; Eriksen, T. K.; Görgen, A.; Guttormsen, M.; Hadynska-Klek, K.; Klintefjord, M.; Larsen, A. C.; Renstrøm, T.; Sahin, E.; Siem, S.; Springer, A.; Tornyi, T. G.; Tveten, G. M.

    2016-10-01

    Particle-γ coincidence data have been analyzed to obtain the nuclear level density and the γ -strength function of 64Ni by means of the Oslo method. The level density found in this work is in very good agreement with known energy levels at low excitation energies as well as with data deduced from particle-evaporation measurements at excitation energies above Ex≈5.5 MeV. The experimental γ -strength function presents an enhancement at γ energies below Eγ≈3 MeV and possibly a resonancelike structure centered at Eγ≈9.2 MeV. The obtained nuclear level density and γ -strength function have been used to estimate the (n ,γ ) cross section for the s -process branch-point nucleus 63Ni, of particular interest for astrophysical calculations of elemental abundances.

  3. A kinematically complete, interdisciplinary, and co-institutional measurement of the 19F(α,n) cross section for nuclear safeguards science

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peters, W. A.; Smith, M. S.; Pittman, S.

    2016-05-01

    Alpha particles emitted from the decay of uranium in a UF 6 matrix can interact with fluorine and generate neutrons via the 19F(α,n) 22Na reaction. These neutrons can be used to determine the uranium content in a UF 6 storage cylinder. The accuracy of this self-interrogating, non-destructive assay (NDA) technique is, however, limited by the uncertainty of the 19F(α,n) 22Na cross section. We have performed complementary measurements of the 19F(α,n) 22Na reaction with both 4He and 19F beams to improve the precision of the 19F(α,n) 22Na cross section over the alpha energy range that encompasses common actinide alpha decay neededmore » for NDA studies. We have determined an absolute cross section for the 19F(α,n) 22Na reaction to an average precision of 7.6% over the alpha energy range of 3.9 – 6.7 MeV. We utilized this cross section in a simulation of a 100 g spherical UF 6 assembly and obtained a change in neutron emission rate values of approximately 10-12%, and a significant (factor of 3.6) decrease in the neutron emission rate uncertainty (from 50-51% to 13-14%), compared to simulations using the old cross section. Our new absolute cross section enables improved interpretations of NDAs of containers of arbitrary size and configuration.« less

  4. Cross-Section Measurement of the 169Tm(n,3n)167Tm Reaction and Constraining the Branching Ratio of 167Tm

    NASA Astrophysics Data System (ADS)

    Champine, Brian; Gooden, Matthew; Thomas, Keenan; Krishichayan, F.; Norman, Eric; Scielzo, Nick; Tonchev, Anton; Tornow, Werner

    2015-10-01

    The cross section of the 169Tm(n,3n)167Tm reaction has been measured from 17.5 to 21.5 MeV using activation technique. This energy region was chosen to resolve the two different trends of the previous (n,3n) cross section measurements on 169Tm. In addition, the branching ratio of the 207.8 keV γ-ray line stemming from electron capture of 167Tm was measured to be 0.419(16). The result of these measurements provide more accurate diagnostic estimation of the so called reaction-in-flight neutrons produced via the internal confinement fusion plasma in deuterium-tritium capsules at the National Ignition Facility.

  5. Measurement of 100- and 290-MeV/A Carbon Incident Neutron Production Cross Sections for Carbon, Nitrogen and Oxygen

    NASA Astrophysics Data System (ADS)

    Shigyo, N.; Uozumi, U.; Uehara, H.; Nishizawa, T.; Mizuno, T.; Takamiya, M.; Hashiguchi, T.; Satoh, D.; Sanami, T.; Koba, Y.; Takada, M.; Matsufuji, N.

    2014-05-01

    Neutron double-differential cross sections from carbon ion incident on carbon, nitrogen and oxygen targets have been measured for neutron energies down to 0.6 MeV in wide directions from 15∘ to 90∘ with 100- and 290-MeV/A incident energies at the Heavy Ion Medical Accelerator in Chiba (HIMAC), National Institute of Radiological Sciences. Two sizes of NE213 scintillators were used as neutron detectors in order to enable neutron energy from below one to several hundred MeV. The neutron energy was measured by the time-of-flight technique between the beam pickup detector and an NE213 scintillator. By using the experimental data, the validity of the calculation results by the PHITS code was examined.

  6. 5 MeV Mott Polarimeter Development at Jefferson Lab

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Price, J. S.; Sinclair, C. K.; Cardman, L. S.

    1997-01-01

    Low energy (E{sub k}=100 keV) Mott scattering polarimeters are ill- suited to support operations foreseen for the polarized electron injector at Jefferson Lab. One solution is to measure the polarization at 5 MeV where multiple and plural scattering are unimportant and precision beam monitoring is straightforward. The higher injector beam current offsets the lower cross-sections. Recent improvements in the CEBAF injector polarimeter scattering chamber have improved signal to noise.

  7. Neutron-induced fission cross section measurements for uranium isotopes 236U and 234U at LANSCE

    NASA Astrophysics Data System (ADS)

    Laptev, A. B.; Tovesson, F.; Hill, T. S.

    2013-04-01

    A well established program of neutron-induced fission cross section measurement at Los Alamos Neutron Science Center (LANSCE) is supporting the Fuel Cycle Research program (FC R&D). The incident neutron energy range spans from sub-thermal up to 200 MeV by combining two LANSCE facilities, the Lujan Center and the Weapons Neutron Research facility (WNR). The time-of-flight method is implemented to measure the incident neutron energy. A parallel-plate fission ionization chamber was used as a fission fragment detector. The event rate ratio between the investigated foil and a standard 235U foil is converted into a fission cross section ratio. In addition to previously measured data new measurements include 236U data which is being analyzed, and 234U data acquired in the 2011-2012 LANSCE run cycle. The new data complete the full suite of Uranium isotopes which were investigated with this experimental approach. Obtained data are presented in comparison with existing evaluations and previous data.

  8. Blister formation at subcritical doses in tungsten irradiated by MeV protons

    NASA Astrophysics Data System (ADS)

    Gavish Segev, I.; Yahel, E.; Silverman, I.; Makov, G.

    2017-12-01

    The material response of tungsten to irradiation by MeV protons has been studied experimentally, in particular with respect to bubble and blister formation. Tungsten samples were irradiated by 2.2 MeV protons at the Soreq Applied Research Accelerator Facility (SARAF) to doses of the order of 1017 protons/cm2 which are below the reported critical threshold for blister formation derived from keV range irradiation studies. Large, well-developed blisters are observed indicating that for MeV range protons the critical threshold is at least an order of magnitude lower than the lowest value reported previously. The effects of fluence, flux, and corresponding temperature on the distribution and characteristics of the obtained blisters were studied. FIB cross sections of several blisters exposed their depth and structure.

  9. L -subshell ionization of Ce, Nd, and Lu by 4-10-MeV C ions

    NASA Astrophysics Data System (ADS)

    Lapicki, G.; Mandal, A. C.; Santra, S.; Mitra, D.; Sarkar, M.; Bhattacharya, D.; Sen, P.; Sarkadi, L.; Trautmann, D.

    2005-08-01

    Ll,Lα,Lβ,Lγ,Lγ1+5,Lγ2+3,Lγ4+4' x-ray production cross sections of Ce58 , Nd60 and Lu71 induced by 4-, 6-, 8-, and 10-MeV carbon ions were measured. For Lu, Lγ2+3 is separated from Lγ2+3+6 after revision of the technique of Datz so that Lγ1+5 was used instead of Lγ1 , the Lγ4+4'/Lγ1+5 ratio was corrected for multiple ionization, and uncertainties in Lγ4+4' were incorporated in the fitting process. L -subshell ionization cross sections were extracted as a weighted average from two combinations of these cross sections, {Lα,Lγ1+5,Lγ2+3} and {Lα,Lγ1+5,Lγ} . It is shown that, to within a few percent, the first of these two combinations results in the identical cross sections as this weighted average. Within 10%, permutations of different sets of single-hole atomic parameters yielded the same ionization cross sections. These cross sections are typically within 15% and at most 35% of the cross sections obtained with atomic parameters that were altered in two different ways for multiple ionization. Extracted subshell and total L -shell ionization cross sections as well as Ce and Nd data of Braziewicz are compared with the ECPSSR theory of Brandt and Lapicki that accounts for the energy-loss (E), Coulomb-deflection (C), perturbed-stationary-state (PSS) and relativistic (R) effects. These measurements are also compared with the ECPSSR theory after its corrections—in a separated and united atom (USA) treatment, and for the intrashell (IS) transitions with the factors of Sarkadi and Mukoyama normalized to match L -shell cross section with the sum of L -subshell cross sections—as well as with the similarly improved semiclassical approximation of Trautmann. For Ce and Nd, the agreement of the extracted ionization cross sections with these theories is poor for L1 and good for L2 , L3 , and total L shell ionization. For the L2 subshell, this agreement is better for Ce and Nd than for Lu. The ECPSSR theory corrected for the USA and IS effects is surprisingly

  10. Fission cross section of 239Th and 232Th relative to 235U

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Meadows, J. W.

    1979-01-01

    The fission cross sections of /sup 230/Th and /sup 232/Th were measured relative to /sup 235/U from near threshold to near 10 MeV. The weights of the thorium samples were determined by isotopic dilution. The weight of the uranium deposit was based on specific activity measurements of a /sup 234/U-/sup 235/U mixture and low geometry alpha counting. Corrections were made for thermal background, loss of fragments in the deposits, neutron scattering in the detector assembly, sample geometry, sample composition and the spectrum of the neutron source. Generally the systematic errors were approx. 1%. The combined systematic and statistical errors weremore » typically 1.5%. 17 references.« less

  11. Description of Differential Cross Sections for 63Cu + p Nuclear Reactions Induced by High-Energy Cosmic-Ray Protons

    NASA Astrophysics Data System (ADS)

    Chuvilskaya, T. V.; Shirokova, A. A.

    2018-03-01

    The results of calculation of 63Cu + p differential cross sections at incident-proton energies between 10 and 200 MeV and a comparative analysis of these results are presented as a continuation of the earlier work of our group on developing methods for calculating the contribution of nuclear reactions to radiative effects arising in the onboard spacecraft electronics under the action of high-energy cosmic-ray protons on 63Cu nuclei (generation of single-event upsets) and as a supplement to the earlier calculations performed on the basis of the TALYS code in order to determine elastic- and inelastic-scattering cross sections and charge, mass, and energy distributions of recoil nuclei (heavy products of the 63Cu + p nuclear reaction). The influence of various mechanisms of the angular distributions of particles emitted in the 63Cu + p nuclear reaction is also discussed.

  12. Measurement of the 169Tm (n ,3 n ) 167Tm cross section and the associated branching ratios in the decay of 167Tm

    NASA Astrophysics Data System (ADS)

    Champine, B.; Gooden, M. E.; Krishichayan, Norman, E. B.; Scielzo, N. D.; Stoyer, M. A.; Thomas, K. J.; Tonchev, A. P.; Tornow, W.; Wang, B. S.

    2016-01-01

    The cross section for the 169Tm(n ,3 n ) 167Tm reaction was measured from 17 to 22 MeV using quasimonoenergetic neutrons produced by the 2H(d ,n ) 3He reaction. This energy range was studied to resolve the discrepancy between previous (n ,3 n ) cross-section measurements. In addition, the absolute γ -ray branching ratios following the electron-capture decay of 167Tm were measured. These results provide more reliable nuclear data for an important diagnostic that is used at the National Ignition Facility to estimate the yield of reaction-in-flight neutrons produced via the inertial-confinement-fusion plasma in deuterium-tritium capsules.

  13. Doppler Broadening and its Contribution to Compton Energy-Absorption Cross Sections: An Analysis of the Compton Component in Terms of Mass-Energy Absorption Coefficient

    NASA Astrophysics Data System (ADS)

    Rao, D. V.; Takeda, T.; Itai, Y.; Akatsuka, T.; Cesareo, R.; Brunetti, A.; Gigante, G. E.

    2002-09-01

    Compton energy absorption cross sections are calculated using the formulas based on a relativistic impulse approximation to assess the contribution of Doppler broadening and to examine the Compton profile literature and explore what, if any, effect our knowledge of this line broadening has on the Compton component in terms of mass-energy absorption coefficient. Compton energy-absorption cross sections are evaluated for all elements, Z=1-100, and for photon energies 1 keV-100 MeV. Using these cross sections, the Compton component of the mass-energy absorption coefficient is derived in the energy region from 1 keV to 1 MeV for all the elements Z=1-100. The electron momentum prior to the scattering event should cause a Doppler broadening of the Compton line. The momentum resolution function is evaluated in terms of incident and scattered photon energy and scattering angle. The overall momentum resolution of each contribution is estimated for x-ray and γ-ray energies of experimental interest in the angular region 1°-180°. Also estimated is the Compton broadening using nonrelativistic formula in the angular region 1°-180°, for 17.44, 22.1, 58.83, and 60 keV photons for a few elements (H, C, N, O, P, S, K, and Ca) of biological importance.

  14. Elastic neutron scattering studies at 96 MeV for transmutation.

    PubMed

    Osterlund, M; Blomgren, J; Hayashi, M; Mermod, P; Nilsson, L; Pomp, S; Ohrn, A; Prokofiev, A V; Tippawan, U

    2007-01-01

    Elastic neutron scattering from (12)C, (14)N, (16)O, (28)Si, (40)Ca, (56)Fe, (89)Y and (208)Pb has been studied at 96 MeV in the10-70 degrees interval, using the SCANDAL (SCAttered Nucleon Detection AssembLy) facility. The results for (12)C and (208)Pb have recently been published, while the data on the other nuclei are under analysis. The achieved energy resolution, 3.7 MeV, is about an order of magnitude better than for any previous experiment above 65 MeV incident energy. A novel method for normalisation of the absolute scale of the cross section has been used. The estimated normalisation uncertainty, 3%, is unprecedented for a neutron-induced differential cross section measurement on a nuclear target. Elastic neutron scattering is of utmost importance for a vast number of applications. Besides its fundamental importance as a laboratory for tests of isospin dependence in the nucleon-nucleon, and nucleon-nucleus, interaction, knowledge of the optical potentials derived from elastic scattering come into play in virtually every application where a detailed understanding of nuclear processes is important. Applications for these measurements are dose effects due to fast neutrons, including fast neutron therapy, as well as nuclear waste incineration and single event upsets in electronics. The results at light nuclei of medical relevance ((12)C, (14)N and (16)O) are presented separately. In the present contribution, results on the heavier nuclei are presented, among which several are of relevance to shielding of fast neutrons.

  15. XCOM: Photon Cross Sections Database

    National Institute of Standards and Technology Data Gateway

    SRD 8 XCOM: Photon Cross Sections Database (Web, free access)   A web database is provided which can be used to calculate photon cross sections for scattering, photoelectric absorption and pair production, as well as total attenuation coefficients, for any element, compound or mixture (Z <= 100) at energies from 1 keV to 100 GeV.

  16. Sensitivity of the fusion cross section to the density dependence of the symmetry energy

    NASA Astrophysics Data System (ADS)

    Reinhard, P.-G.; Umar, A. S.; Stevenson, P. D.; Piekarewicz, J.; Oberacker, V. E.; Maruhn, J. A.

    2016-04-01

    Background: The study of the nuclear equation of state (EOS) and the behavior of nuclear matter under extreme conditions is crucial to our understanding of many nuclear and astrophysical phenomena. Nuclear reactions serve as one of the means for studying the EOS. Purpose: It is the aim of this paper to discuss the impact of nuclear fusion on the EOS. This is a timely subject given the expected availability of increasingly exotic beams at rare isotope facilities [A. B. Balantekin et al., Mod. Phys. Lett. A 29, 1430010 (2014), 10.1142/S0217732314300109]. In practice, we focus on 48Ca+48Ca fusion. Method: We employ three different approaches to calculate fusion cross sections for a set of energy density functionals with systematically varying nuclear matter properties. Fusion calculations are performed using frozen densities, using a dynamic microscopic method based on density-constrained time-dependent Hartree-Fock (DC-TDHF) approach, as well as direct TDHF study of above barrier cross sections. For these studies, we employ a family of Skyrme parametrizations with systematically varied nuclear matter properties. Results: The folding-potential model provides a reasonable first estimate of cross sections. DC-TDHF, which includes dynamical polarization, reduces the fusion barriers and delivers much better cross sections. Full TDHF near the barrier agrees nicely with DC-TDHF. Most of the Skyrme forces which we used deliver, on the average, fusion cross sections in good agreement with the data. Trying to read off a trend in the results, we find a slight preference for forces which deliver a slope of symmetry energy of L ≈50 MeV that corresponds to a neutron-skin thickness of 48Ca of Rskin=(0.180 -0.210 ) fm. Conclusions: Fusion reactions in the barrier and sub-barrier region can be a tool to study the EOS and the neutron skin of nuclei. The success of the approach will depend on reduced experimental uncertainties of fusion data as well as the development of fusion

  17. Oscillator strengths and integral cross sections for the valence-shell excitations of nitric oxide studied by fast electron impact.

    PubMed

    Xu, Xin; Xu, Long-Quan; Xiong, Tao; Chen, Tao; Liu, Ya-Wei; Zhu, Lin-Fan

    2018-01-28

    The generalized oscillator strengths for the valence-shell excitations of A 2 Σ + , C 2 Π, and D 2 Σ + electronic-states of nitric oxide have been determined at an incident electron energy of 1500 eV with an energy resolution of 70 meV. The optical oscillator strengths for these transitions have been obtained by extrapolating the generalized oscillator strengths to the limit that the squared momentum transfer approaches to zero, which give an independent cross-check to the previous experimental and theoretical results. The integral cross sections for the valence-shell excitations of nitric oxide have been determined systematically from the threshold to 2500 eV with the aid of the newly developed BE-scaling method for the first time. The present optical oscillator strengths and integral cross sections of the valence-shell excitations of nitric oxide play an important role in understanding many physics and chemistry of the Earth's upper atmosphere such as the radiative cooling, ozone destruction, day glow, aurora, and so on.

  18. Capture cross sections on unstable nuclei

    NASA Astrophysics Data System (ADS)

    Tonchev, A. P.; Escher, J. E.; Scielzo, N.; Bedrossian, P.; Ilieva, R. S.; Humby, P.; Cooper, N.; Goddard, P. M.; Werner, V.; Tornow, W.; Rusev, G.; Kelley, J. H.; Pietralla, N.; Scheck, M.; Savran, D.; Löher, B.; Yates, S. W.; Crider, B. P.; Peters, E. E.; Tsoneva, N.; Goriely, S.

    2017-09-01

    Accurate neutron-capture cross sections on unstable nuclei near the line of beta stability are crucial for understanding the s-process nucleosynthesis. However, neutron-capture cross sections for short-lived radionuclides are difficult to measure due to the fact that the measurements require both highly radioactive samples and intense neutron sources. Essential ingredients for describing the γ decays following neutron capture are the γ-ray strength function and level densities. We will compare different indirect approaches for obtaining the most relevant observables that can constrain Hauser-Feshbach statistical-model calculations of capture cross sections. Specifically, we will consider photon scattering using monoenergetic and 100% linearly polarized photon beams. Challenges that exist on the path to obtaining neutron-capture cross sections for reactions on isotopes near and far from stability will be discussed.

  19. Radial secondary electron dose profiles and biological effects in light-ion beams based on analytical and Monte Carlo calculations using distorted wave cross sections.

    PubMed

    Wiklund, Kristin; Olivera, Gustavo H; Brahme, Anders; Lind, Bengt K

    2008-07-01

    To speed up dose calculation, an analytical pencil-beam method has been developed to calculate the mean radial dose distributions due to secondary electrons that are set in motion by light ions in water. For comparison, radial dose profiles calculated using a Monte Carlo technique have also been determined. An accurate comparison of the resulting radial dose profiles of the Bragg peak for (1)H(+), (4)He(2+) and (6)Li(3+) ions has been performed. The double differential cross sections for secondary electron production were calculated using the continuous distorted wave-eikonal initial state method (CDW-EIS). For the secondary electrons that are generated, the radial dose distribution for the analytical case is based on the generalized Gaussian pencil-beam method and the central axis depth-dose distributions are calculated using the Monte Carlo code PENELOPE. In the Monte Carlo case, the PENELOPE code was used to calculate the whole radial dose profile based on CDW data. The present pencil-beam and Monte Carlo calculations agree well at all radii. A radial dose profile that is shallower at small radii and steeper at large radii than the conventional 1/r(2) is clearly seen with both the Monte Carlo and pencil-beam methods. As expected, since the projectile velocities are the same, the dose profiles of Bragg-peak ions of 0.5 MeV (1)H(+), 2 MeV (4)He(2+) and 3 MeV (6)Li(3+) are almost the same, with about 30% more delta electrons in the sub keV range from (4)He(2+)and (6)Li(3+) compared to (1)H(+). A similar behavior is also seen for 1 MeV (1)H(+), 4 MeV (4)He(2+) and 6 MeV (6)Li(3+), all classically expected to have the same secondary electron cross sections. The results are promising and indicate a fast and accurate way of calculating the mean radial dose profile.

  20. Measurement of the 19F(α,n)22Na Cross Section for Nuclear Safeguards Science

    NASA Astrophysics Data System (ADS)

    Lowe, Marcus; Smith, M. S.; Pain, S.; Febbraro, M.; Pittman, S.; Chipps, K. A.; Thompson, S. J.; Grinder, M.; Grzywacz, R.; Smith, K.; Thornsberry, C.; Thompson, P.; Peters, W. A.; Waddell, D.; Blanchard, R.; Carls, A.; Shadrick, S.; Engelhardt, A.; Hertz-Kintish, D.; Allen, N.; Sims, H.

    2015-10-01

    Enriched uranium is commonly stored in fluoride matrices such as UF6. Alpha decays of uranium in UF6 will create neutrons via the 19F(α,n)22Na reaction. An improved cross section for this reaction will enable improved nondestructive assays of uranium content in storage cylinders at material enrichment facilities. To determine this reaction cross section, we have performed experiments using both forward and inverse kinematic techniques at the University of Notre Dame (forward) and Oak Ridge National Laboratory (inverse). Both experiments utilized the Versatile Array of Neutron Detectors at Low Energy (VANDLE) for neutron detection. The ORNL experiment also used a new ionization chamber for 22Na particle identification. Gating on the 22Na nuclei detected drastically reduced the background counts in the neutron time-of-flight spectra. The latest analysis and results will be presented for 19F beam energies ranging from 20-37 MeV. This work is funded in part by the DOE Office of Nuclear Physics, the National Nuclear Security Administration's Office of Defense Nuclear Nonproliferation R&D, and the NSF.

  1. Cross-Sectional Analysis of Longitudinal Mediation Processes.

    PubMed

    O'Laughlin, Kristine D; Martin, Monica J; Ferrer, Emilio

    2018-01-01

    Statistical mediation analysis can help to identify and explain the mechanisms behind psychological processes. Examining a set of variables for mediation effects is a ubiquitous process in the social sciences literature; however, despite evidence suggesting that cross-sectional data can misrepresent the mediation of longitudinal processes, cross-sectional analyses continue to be used in this manner. Alternative longitudinal mediation models, including those rooted in a structural equation modeling framework (cross-lagged panel, latent growth curve, and latent difference score models) are currently available and may provide a better representation of mediation processes for longitudinal data. The purpose of this paper is twofold: first, we provide a comparison of cross-sectional and longitudinal mediation models; second, we advocate using models to evaluate mediation effects that capture the temporal sequence of the process under study. Two separate empirical examples are presented to illustrate differences in the conclusions drawn from cross-sectional and longitudinal mediation analyses. Findings from these examples yielded substantial differences in interpretations between the cross-sectional and longitudinal mediation models considered here. Based on these observations, researchers should use caution when attempting to use cross-sectional data in place of longitudinal data for mediation analyses.

  2. Measurement of the 64Zn,47Ti(n,p) cross sections using a DD neutron generator for medical isotope studies

    NASA Astrophysics Data System (ADS)

    Voyles, A. S.; Basunia, M. S.; Batchelder, J. C.; Bauer, J. D.; Becker, T. A.; Bernstein, L. A.; Matthews, E. F.; Renne, P. R.; Rutte, D.; Unzueta, M. A.; van Bibber, K. A.

    2017-11-01

    Cross sections for the 47Ti(n,p)47Sc and 64Zn(n,p)64Cu reactions have been measured for quasi-monoenergetic DD neutrons produced by the UC Berkeley High Flux Neutron Generator (HFNG). The HFNG is a compact neutron generator designed as a "flux-trap" that maximizes the probability that a neutron will interact with a sample loaded into a specific, central location. The study was motivated by interest in the production of 47Sc and 64Cu as emerging medical isotopes. The cross sections were measured in ratio to the 113In(n,n‧)113mIn and 115In(n,n‧)115mIn inelastic scattering reactions on co-irradiated indium samples. Post-irradiation counting using an HPGe and LEPS detectors allowed for cross section determination to within 5% uncertainty. The 64Zn(n,p)64Cu cross section for 2.76-0.02+0.01 MeV neutrons is reported as 49.3 ± 2.6 mb (relative to 113In) or 46.4 ± 1.7 mb (relative to 115In), and the 47Ti(n,p)47Sc cross section is reported as 26.26 ± 0.82 mb. The measured cross sections are found to be in good agreement with existing measured values but with lower uncertainty (<5%), and also in agreement with theoretical values. This work highlights the utility of compact, flux-trap DD-based neutron sources for nuclear data measurements and potentially the production of radionuclides for medical applications.

  3. Experimental study on beryllium-7 production via sequential reactions in lithium-containing compounds irradiated by 14 MeV neutrons

    NASA Astrophysics Data System (ADS)

    Maekawa, F.; Verzilov, Y. M.; Smith, D. L.; Ikeda, Y.

    2000-12-01

    Except for 3H and 14C, no radioactive nuclide is produced by neutron-induced reactions with lithium in lithium-containing materials such as Li 2O and Li 2CO 3. However, when the lithium-containing materials are irradiated by 14 MeV neutrons, radioactive 7Be is produced by sequential charged particle reactions (SCPR). In this study, we measured effective 7Be production cross-sections in several lithium-containing samples at 14 MeV: the cross-sections are in the order of μb. Estimation of the effective cross-sections is attempted, and the estimated values agreed well with the experimental data. It was shown that the 7Be activity in a unit volume of lithium-containing materials in D-T fusion reactors can exceed total activity of the same unit volume of the SiC structural material in a certain cooling time. Consequently, a careful consideration of the 7Be production by SCPR is required to assess radioactive inventories in lithium-containing D-T fusion blanket materials.

  4. Capture cross sections on unstable nuclei

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tonchev, A. P.; Escher, J. E.; Scielzo, N.

    2017-09-13

    Accurate neutron-capture cross sections on unstable nuclei near the line of beta stability are crucial for understanding the s-process nucleosynthesis. However, neutron-capture cross sections for short-lived radionuclides are difficult to measure due to the fact that the measurements require both highly radioactive samples and intense neutron sources. Essential ingredients for describing the γ decays following neutron capture are the γ-ray strength function and level densities. We will compare different indirect approaches for obtaining the most relevant observables that can constrain Hauser-Feshbach statistical-model calculations of capture cross sections. Specifically, we will consider photon scattering using monoenergetic and 100% linearly polarized photonmore » beams. Here, challenges that exist on the path to obtaining neutron-capture cross sections for reactions on isotopes near and far from stability will be discussed.« less

  5. DBCC Software as Database for Collisional Cross-Sections

    NASA Astrophysics Data System (ADS)

    Moroz, Daniel; Moroz, Paul

    2014-10-01

    Interactions of species, such as atoms, radicals, molecules, electrons, and photons, in plasmas used for materials processing could be very complex, and many of them could be described in terms of collisional cross-sections. Researchers involved in plasma simulations must select reasonable cross-sections for collisional processes for implementing them into their simulation codes to be able to correctly simulate plasmas. However, collisional cross-section data are difficult to obtain, and, for some collisional processes, the cross-sections are still not known. Data on collisional cross-sections can be obtained from numerous sources including numerical calculations, experiments, journal articles, conference proceedings, scientific reports, various universities' websites, national labs and centers specifically devoted to collecting data on cross-sections. The cross-sections data received from different sources could be partial, corresponding to limited energy ranges, or could even not be in agreement. The DBCC software package was designed to help researchers in collecting, comparing, and selecting cross-sections, some of which could be constructed from others or chosen as defaults. This is important as different researchers may place trust in different cross-sections or in different sources. We will discuss the details of DBCC and demonstrate how it works and why it is beneficial to researchers working on plasma simulations.

  6. Neutron radiative capture cross section of Cu,6563 between 0.4 and 7.5 MeV

    NASA Astrophysics Data System (ADS)

    Newsome, I.; Bhike, M.; Krishichayan, Tornow, W.

    2018-04-01

    Natural copper is commonly used as cooling and shielding medium in detector arrangements designed to search for neutrinoless double-β decay. Neutron-induced background reactions on copper could potentially produce signals that are indistinguishable from the signals of interest. The present work focuses on radiative neutron capture experiments on Cu,6563 in the 0.4 to 7.5 MeV neutron energy range. The new data provide evaluations and model calculations with benchmark data needed to extend their applicability in predicting background rates in neutrinoless double-β decay experiments.

  7. Measurements of the total cross section of natBe with thermal neutrons from a photo-neutron source

    NASA Astrophysics Data System (ADS)

    Liu, L. X.; Wang, H. W.; Ma, Y. G.; Cao, X. G.; Cai, X. Z.; Chen, J. G.; Zhang, G. L.; Han, J. L.; Zhang, G. Q.; Hu, J. F.; Wang, X. H.; Li, W. J.; Yan, Z.; Fu, H. J.

    2017-11-01

    The total neutron cross sections of natural beryllium in the neutron energy region of 0.007 to 0.1 eV were measured by using a time-of-flight (TOF) technique at the Shanghai Institute of Applied Physics (SINAP). The low energy neutrons were obtained by moderating the high energy neutrons from a pulsed photo-neutron source generated from a 16 MeV electron linac. The time dependent neutron background component was determined by employing the 12.8 cm boron-loaded polyethylene (PEB) (5% w.t.) to block neutron TOF path and using the Monte Carlo simulation methods. The present data was compared with the fold Harvey data with the response function of the photo-neutron source (PNS, phase-1). The present measurement of total cross section of natBe for thermal neutrons based on PNS has been developed for the acquisition of nuclear data needed for the Thorium Molten Salt Reactor (TMSR).

  8. Testing helicity-dependent γγ → γγ scattering in the region of MeV

    NASA Astrophysics Data System (ADS)

    Homma, K.; Matsuura, K.; Nakajima, K.

    2016-01-01

    Light-by-light scatterings contain rich information on photon coupling to virtual and real particle states. In the context of quantum electrodynamics (QED), photons can couple to a virtual e^+e^- pair. Photons may also couple to known resonance states in the context of quantum chromodyanmics and electroweak dynamics in higher energy domains and possibly couple to unknown resonance states beyond the standard model. The perturbative QED calculations manifestly predict a maximized cross section at the MeV scale; however, no example of exact real-photon-real-photon scattering has yet been observed. Hence, we propose direct measurement with the maximized cross section at the center-of-mass system energy of 1-2 MeV to establish a firm footing at the MeV scale. Given current state of the art high power lasers, helicity-dependent elastic scattering may be observed at a reasonable rate, if a photon-photon collider exploiting γ -rays generated by the inverse nonlinear Compton process with electrons delivered from laser-plasma accelerators (LPA) are properly designed. We show that such verification is feasible in a table-top scale collider, which may be an unprecedented breakthrough in particle accelerators for basic physics research in contrast to energy frontier colliders.

  9. Ion dipole capture cross sections at low ion and rotational energies - Comparison of integrated capture cross sections with reaction cross sections for NH3 and H2O parent-ion collisions.

    NASA Technical Reports Server (NTRS)

    Dugan, J. V., Jr.; Canright, R. B., Jr.

    1972-01-01

    The numerical capture cross section is calculated from the capture ratio, defined as the fraction of trajectories reaching a prescribed minimum separation of 3 A. The calculated capture cross sections for a rotational temperature of 77 K suggest large reaction cross sections in 80 K experiments for the large dipole-moment target, methyl cyanide.

  10. Investigation of activation cross section data of alpha particle induced nuclear reaction on molybdenum up to 40 MeV: Review of production routes of medically relevant 97,103Ru

    NASA Astrophysics Data System (ADS)

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

    2017-05-01

    The main goals of this investigations were to expand and consolidate reliable activation cross-section data for the natMo(α,x) reactions in connection with production of medically relevant 97,103Ru and the use of the natMo(α,x)97Ru reaction for monitoring beam parameters. The excitation functions for formation of the gamma-emitting radionuclides 94Ru, 95Ru, 97Ru, 103Ru, 93mTc, 93gTc(m+), 94mTc, 94gTc, 95mTc, 95gTc, 96gTc(m+), 99mTc, 93mMo, 99Mo(cum), 90Nb(m+) and 88Zr were measured up to 40 MeV alpha-particle energy by using the stacked foil technique and activation method. Data of our earlier similar experiments were re-evaluated and resulted in corrections on the reported results. Our experimental data were compared with critically analyzed literature data and with the results of model calculations, obtained by using the ALICE-IPPE, EMPIRE 3.1 (Rivoli) and TALYS codes (TENDL-2011 and TENDL-2015 on-line libraries). Nuclear data for different production routes of 97Ru and 103Ru are compiled and reviewed.

  11. Valine radiolysis by MeV ions

    NASA Astrophysics Data System (ADS)

    Da Silveira, Enio

    2016-07-01

    Valine, (CH3)2 CHCH (NH2) COOH, is a protein amino acid that has been identified in extraterrestrial environments and in the Murchison meteorite [1]. The knowledge of half-lives of small organic molecules under ionizing radiation is important for the setup of models describing the spread out of prebiotics across the Solar System or the Galaxy. We have investigated typical effects of MeV cosmic ray ions on prebiotic molecules in laboratory by impinging ions produced by the PUC-Rio Van de Graaff accelerator. Pure valine films, deposited by evaporation on KBr substrates, were irradiated by H ^{+}, He ^{+} and N ^{+} ion beams, from 0.5 to 1.5 MeV and up to a fluence of 10 ^{15} projectiles/cm ^{2}. The sample temperature was varied from 10 K to 300 K. The irradiation was interrupted several times for Mid-FTIR analysis of the sample. The main findings are: 1- The column density of the valine decreases exponentially with fluence. 2- In some cases, a second exponential appears in the beginning of irradiation; this feature has been attributed to sample compaction by the ion beam [2]. 3- Destruction cross sections of valine are in the 10 ^{-15} cm ^{2} range, while compaction cross sections are in the 10 ^{-14} cm ^{2} range. 4- Destruction cross section increases with the stopping power of the beam and also with the sample temperature. 5- Surprisingly, during the radiolysis of valine, just CO _{2} is seen by as a daughter molecule formed in the bulk. 6- After long beam fluence, also a CO peak appears in the infrared spectrum; this species is however interpreted as a fragment of the formed CO2 molecules. 7- Considering the flux ratio between laboratory experiments and actual galactic cosmic rays, half-life of valine is predicted for ISM conditions [3]. This work on pure valine is the first measurement of a series. New experiments are planned for determining cross sections of valine dissolved in H _{2}O or CO _{2}, inspired by the study performed for glycine [4]. [1] P

  12. Elastic scattering and total reaction cross section for the 6He +58Ni system

    NASA Astrophysics Data System (ADS)

    Morcelle, V.; Lichtenthäler, R.; Lépine-Szily, A.; Guimarães, V.; Mendes, D. R., Jr.; Pires, K. C. C.; de Faria, P. N.; Barioni, A.; Gasques, L.; Morais, M. C.; Shorto, J. M. B.; Zamora, J. C.; Scarduelli, V.; Condori, R. Pampa; Leistenschneider, E.

    2014-11-01

    Elastic scattering measurements of 6He + 58Ni system have been performed at the laboratory energy of 21.7 MeV. The 6He secondary beam was produced by a transfer reaction 9Be (7Li , 6He ) and impinged on 58Ni and 197Au targets, using the Radioactive Ion Beam (RIB) facility, RIBRAS, installed in the Pelletron Laboratory of the Institute of Physics of the University of São Paulo, Brazil. The elastic angular distribution was obtained in the angular range from 15° to 80° in the center of mass frame. Optical model calculations have been performed using a hybrid potential to fit the experimental data. The total reaction cross section was derived.

  13. Accurate Cross Sections for Microanalysis.

    PubMed

    Rez, Peter

    2002-01-01

    To calculate the intensity of x-ray emission in electron beam microanalysis requires a knowledge of the energy distribution of the electrons in the solid, the energy variation of the ionization cross section of the relevant subshell, the fraction of ionizations events producing x rays of interest and the absorption coefficient of the x rays on the path to the detector. The theoretical predictions and experimental data available for ionization cross sections are limited mainly to K shells of a few elements. Results of systematic plane wave Born approximation calculations with exchange for K, L, and M shell ionization cross sections over the range of electron energies used in microanalysis are presented. Comparisons are made with experimental measurement for selected K shells and it is shown that the plane wave theory is not appropriate for overvoltages less than 2.5 V.

  14. Partial Photoneutron Cross Sections for 207,208Pb

    NASA Astrophysics Data System (ADS)

    Kondo, T.; Utsunomiya, H.; Goriely, S.; Iwamoto, C.; Akimune, H.; Yamagata, T.; Toyokawa, H.; Harada, H.; Kitatani, F.; Lui, Y.-W.; Hilaire, S.; Koning, A. J.

    2014-05-01

    Using linearly-polarized laser-Compton scattering γ-rays, partial E1 and M1 photoneutron cross sections along with total cross sections were determined for 207,208Pb at four energies near neutron threshold by measuring anisotropies in photoneutron emission. Separately, total photoneutron cross sections were measured for 207,208Pb with a high-efficiency 4π neutron detector. The partial cross section measurement provides direct evidence for the presence of pygmy dipole resonance (PDR) in 207,208Pb in the vicinity of neutron threshold. The strength of PDR amounts to 0.32%-0.42% of the Thomas-Reiche-Kuhn sum rule. Several μN2 units of B(M1)↑ strength were observed in 207,208Pb just above neutron threshold, which correspond to M1 cross sections less than 10% of the total photoneutron cross sections.

  15. Calculation of total electron excitation cross-sections and partial electron ionization cross-sections for the elements. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Green, T. J.

    1973-01-01

    Computer programs were used to calculate the total electron excitation cross-section for atoms and the partial ionization cross-section. The approximations to the scattering amplitude used are as follows: (1) Born, Bethe, and Modified Bethe for non-exchange excitation; (2) Ochkur for exchange excitation; and (3) Coulomb-Born of non-exchange ionization. The amplitudes are related to the differential cross-sections which are integrated to give the total excitation (or partial ionization) cross-section for the collision. The atomic wave functions used are Hartree-Fock-Slater functions for bound states and the coulomb wave function for the continuum. The programs are presented and the results are examined.

  16. Understanding the fusion cross section among light nuclei around the Coulomb barrier

    NASA Astrophysics Data System (ADS)

    Del Zoppo, Antonio; La Cognata, Marco

    2017-11-01

    In this work we investigate fusion induced by a radioactive 8Li projectile on a 4He gas target, at center-of-mass energies between 0.6 and 5 MeV. The main result is the tendency of the dimensionless fusion cross section to form well visible plateaus alternated to steep rises. This is likely to be the most genuine consequence of the discrete nature of the intervening angular momenta observed so far in fusion reactions right above the Coulomb barrier. A partial-wave analysis, exclusively based on a pure quantal penetration fusion model, identifies a remarkably low-height barrier. Indeed, these plateaus allow enhanced experimental sensitivity to the fusion barrier given that the most barrier-sensitive lowest partial waves are well separated. We expect that the present results for 8Li+4He will promote further investigations of the fusion reaction mechanism between very light ions at energies much below the interaction barrier. For the moment, we believe that understanding the plateau origin in the cross section above the barrier will almost certainly be useful to corroborate the extrapolation to the important astrophysical region below the Coulomb barrier, not only in the case of the 8Li+4He fusion but also for other systems, such as the 12C+12C.

  17. Absolute and relative cross section measurements of 237Np(n,f) and 238U(n,f) at the National Physical Laboratory

    NASA Astrophysics Data System (ADS)

    Salvador-Castiñeira, Paula; Hambsch, Franz-Josef; Göök, Alf; Vidali, Marzio; Hawkes, Nigel P.; Roberts, Neil J.; Taylor, Graeme C.; Thomas, David J.

    2017-09-01

    Cross section measurements in the fast energy region are being demanded as one of the key ingredients for modelling Generation-IV nuclear power plants. However, in facilities where there are no time-of-flight possibilities or it is not convenient to use them, using the 235U(n,f) cross section as a benchmark would require a careful knowledge of the room scatter in the experimental area. In this paper we present measurements of two threshold reactions, 238U(n,f) and 237Np(n,f), that could become a standard between their fission threshold and 2.5 MeV, if the discrepancies shown in the evaluations and in some experimental data can be solved. The preliminary results are in agreement with the present ENDF/B-VII.1 evaluation.

  18. Averaging cross section data so we can fit it

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brown, D.

    2014-10-23

    The 56Fe cross section we are interested in have a lot of fluctuations. We would like to fit the average of the cross section with cross sections calculated within EMPIRE. EMPIRE is a Hauser-Feshbach theory based nuclear reaction code, requires cross sections to be smoothed using a Lorentzian profile. The plan is to fit EMPIRE to these cross sections in the fast region (say above 500 keV).

  19. Benchmarking the evaluated proton differential cross sections suitable for the EBS analysis of natSi and 16O

    NASA Astrophysics Data System (ADS)

    Kokkoris, M.; Dede, S.; Kantre, K.; Lagoyannis, A.; Ntemou, E.; Paneta, V.; Preketes-Sigalas, K.; Provatas, G.; Vlastou, R.; Bogdanović-Radović, I.; Siketić, Z.; Obajdin, N.

    2017-08-01

    The evaluated proton differential cross sections suitable for the Elastic Backscattering Spectroscopy (EBS) analysis of natSi and 16O, as obtained from SigmaCalc 2.0, have been benchmarked over a wide energy and angular range at two different accelerator laboratories, namely at N.C.S.R. 'Demokritos', Athens, Greece and at Ruđer Bošković Institute (RBI), Zagreb, Croatia, using a variety of high-purity thick targets of known stoichiometry. The results are presented in graphical and tabular forms, while the observed discrepancies, as well as, the limits in accuracy of the benchmarking procedure, along with target related effects, are thoroughly discussed and analysed. In the case of oxygen the agreement between simulated and experimental spectra was generally good, while for silicon serious discrepancies were observed above Ep,lab = 2.5 MeV, suggesting that a further tuning of the appropriate nuclear model parameters in the evaluated differential cross-section datasets is required.

  20. Angular momentum dependence in 22 MeV $alpha$-particle elastic scattering by light nuclei

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lega, J.; Macq, P.C.

    1974-01-01

    Elastic scattering of 22 MeV alpha -particles by /sup 23, /sup 24,15,26/ Mg, /sup 27/Al and /sup 28/Si was measured between 24 and 174 deg lab. Partial angular distributions, from 120 to 174 deg , were also measured at incident energies of 18.4 and 20.7 MeV for /sup 24/Mg, and 18.9 and 20.5 MeV for /sup 28/ Si. The most striking feature of the data is the large-angle behavior spin-zero nuclei display more pronounced backward oscillations and the cross section rises more steeply towards 180 deg for 4n nuclei than for the others. Optical Model analyses with an l-dependent absorptionmore » and a minimum of free parameters are used to describe the general trend of the data for A = 23 to 28 nuclei at different energies; a spinorbit coupling term, 2.75 MeV deep, is added to describe the /sup 23/Na scattering data. (auth)« less

  1. Cross sections for electron collision with difluoroacetylene

    NASA Astrophysics Data System (ADS)

    Gupta, Dhanoj; Choi, Heechol; Kwon, Deuk-Chul; Yoon, Jung-Sik; Antony, Bobby; Song, Mi-Young

    2017-04-01

    We report a detailed calculation of total elastic, differential elastic, momentum transfer and electronic excitation for electron impact on difluoroacetylene (C2F2) molecules using the R-matrix method at low energies. After testing many target models, the final results are reported for the target model that gave the best target properties and predicted the lowest value of the shape resonance. The shape resonance is detected at 5.86 eV and 6.49 eV with the close-coupling and static exchange models due to 2Πg (2B2g, 2B3g) states. We observed that the effect of polarization becomes prominent at low energies below 4 eV, decreasing the magnitude of the elastic cross section systematically as it increases for C2F2. We have also computed elastic cross sections for C2H2, C2F4 and C2H4 with a similar model and compared with the experimental data for these molecules along with C2F2. General agreement is found in terms of the shape and nature of the cross section. Such a comparison shows the reliability of the present method for obtaining the cross section for C2F2. The calculation of elastic scattering cross section is extended to higher energies up to 5 keV using the spherical complex optical potential method. The two methods are found to be consistent, merging at around 12 eV for the elastic scattering cross section. Finally we report the total ionization cross section using the binary encounter Bethe method for C2F2. The perfluorination effect in the shape and magnitude of the elastic, momentum transfer and ionization cross sections when compared with C2H2 showed a similar trend to that in the C2H4-C2F4 and C6H6-C6F6 systems. The cross-section data reported in this article could be an important input for the development of a C2F2 plasma model for selective etching of Si/SiO2 in the semiconductor industry.

  2. Differential cross sections for the reactions γ p → p η and γ p → p η '

    DOE PAGES

    Williams, M.; Krahn, Z.; Applegate, D.; ...

    2009-10-29

    In high-statistics differential cross sections for the reactions γ p -> p η and γ p -> p η' the CLAS at Jefferson Lab was used to measure the center-of-mass energies from near threshold up to 2.84 GeV. The eta-prime results are the most precise to date and provide the largest energy and angular coverage. The eta measurements extend the energy range of the world's large-angle results by approximately 300 MeV. These new data, in particular the η' measurements, are likely to help constrain the analyses being performed to search for new baryon resonance states.

  3. Investigation of Activation Cross Sections of the Proton Induced Nuclear Reactions on Natural Iron at Medium Energies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ditroi, F.; Tarkanyi, F.; Csikai, J.

    2005-05-24

    Iron is one of the most important structural materials in every field of science, technology, industry, etc. Its application in a radiating environment requires the knowledge of accurate excitation functions for the possible reactions in question. By using the Thin Layer Activation technique (TLA) the knowledge of such data is also extremely important even in the case of relative measurements to design the irradiation (irradiation energy, beam intensity, duration) and also for radioactive safety estimations. The cross sections are frequently measured at low energies but there are unsatisfactory and unreliable data in the energy range above 40 MeV.

  4. Investigation of Activation Cross Sections of the Proton Induced Nuclear Reactions on Natural Iron at Medium Energies

    NASA Astrophysics Data System (ADS)

    Ditrói, F.; Tárkányi, F.; Csikai, J.; Uddin, M. S.; Hagiwara, M.; Baba, M.

    2005-05-01

    Iron is one of the most important structural materials in every field of science, technology, industry, etc. Its application in a radiating environment requires the knowledge of accurate excitation functions for the possible reactions in question. By using the Thin Layer Activation technique (TLA) the knowledge of such data is also extremely important even in the case of relative measurements to design the irradiation (irradiation energy, beam intensity, duration) and also for radioactive safety estimations. The cross sections are frequently measured at low energies but there are unsatisfactory and unreliable data in the energy range above 40 MeV.

  5. Comparison of x-ray cross sections for diagnostic and therapeutic medical physics.

    PubMed

    Boone, J M; Chavez, A E

    1996-12-01

    The purpose of this technical report is to make available an up-to-date source of attenuation coefficient data to the medical physics community, and to compare these data with other more familiar sources. Data files from Lawrence Livermore National Laboratory (in Livermore, CA) were truncated to match the needs of the medical physics community, and an interpolation routine was written to calculate a continuous set of cross sections spanning energies from 1 keV to 50 MeV. Coefficient data are available for elements Z = 1 through Z = 100. Values for mass attenuation coefficients, mass-energy-transfer coefficients, and mass-energy absorption coefficients are produced by a single computer subroutine. In addition to total interaction cross sections, the cross sections for photoelectric, Rayleigh, Compton, pair, and some triplet interactions are also produced by this single program. The coefficients were compared to the 1970 data of Storm and Israel over the energy interval from 1 to 1000 keV; for elements 10, 20, 30, 40, 50, 60, 70, and 80, the average positive difference between the Storm and Israel coefficients and the coefficients reported here are 1.4%, 2.7%, and 2.6%, for the mass attenuation, mass energy-transfer, and mass-energy absorption coefficients, respectively. The 1969 data compilation of mass attenuation coefficients from McMaster et al. were also compared with the newer LLNL data. Over the energy region from 10 keV to 1000 keV, and from elements Z = 1 to Z = 82 (inclusive), the overall average difference was 1.53% (sigma = 0.85%). While the overall average difference was small, there was larger variation (> 5%) between cross sections for some elements. In addition to coefficient data, other useful data such as the density, atomic weight, K, L1, L2, L3, M, and N edges, and numerous characteristic emission energies are output by the program, depending on a single input variable. The computer source code, written in C, can be accessed and downloaded from

  6. COPPER-64 Production Studies with Natural Zinc Targets at Deuteron Energy up to 19 Mev and Proton Energy from 141 Down to 31 Mev

    NASA Astrophysics Data System (ADS)

    Bonardi, Mauro L.; Birattari, Claudio; Groppi, Flavia; Song Mainard, Hae; Zhuikov, Boris L.; Kokhanyuk, Vladimir M.; Lapshina, Elena V.; Mebel, Michail V.; Menapace, Enzo

    2004-07-01

    High specific activity no-carrier-added 64Cu is a β-/β+ emitting radionuclide of increasing interest for PET imaging, as well as systemic and targeted radioimmunotherapy of tumors. Its peculiarity of intense Auger emitter is still under investigation. The cross-sections for production of 64Cu from Zn target of natural isotopic composition were measured in the deuteron energy range from threshold up to 19 MeV and proton energy range from 141 down to 31 MeV. The stacked-foil technique was used at both K=38 cyclotron of JRC-Ispra of CEC, Italy and 160 MeV intersection point of INR proton-LINAC in Troitsk, Russia. Several Ga, Zn, Cu, Ni, Co, V, Fe and Mn radionuclides were detected in Zn targets at the EOB. Optimized irradiation conditions are reported as a function of deuteron energy and energy loss into the Zn target, as well as target irradiation time and cooling time after radiochemistry. The activity of n.c.a. 64Cu was measured through its only γ emission of 1346 keV (i.e. 0.473 % intensity) both by instrumental and radiochemical methods, due to the non-specificity of annihilation radiation at 511 keV. To this last purpose, it was necessary to carry out a selective radiochemical separation of GaIII radionuclides by liquid/liquid extraction from the bulk of irradiated Zn targets and other spallation products, which remained in the 7 M HCl aqueous phase. Anion exchange chromatography tests had been carried out to separate the 64Cu from all others radionuclides in n.c.a. form. Theoretical calculations of cross-sections were performed with codes EMPIRE II and PENELOPE for deuteron reactions and CEF model and HMS-ALICE hybrid model for proton reactions. The theoretical results are presented and compared with the experimental values.

  7. Methodology Series Module 3: Cross-sectional Studies.

    PubMed

    Setia, Maninder Singh

    2016-01-01

    Cross-sectional study design is a type of observational study design. In a cross-sectional study, the investigator measures the outcome and the exposures in the study participants at the same time. Unlike in case-control studies (participants selected based on the outcome status) or cohort studies (participants selected based on the exposure status), the participants in a cross-sectional study are just selected based on the inclusion and exclusion criteria set for the study. Once the participants have been selected for the study, the investigator follows the study to assess the exposure and the outcomes. Cross-sectional designs are used for population-based surveys and to assess the prevalence of diseases in clinic-based samples. These studies can usually be conducted relatively faster and are inexpensive. They may be conducted either before planning a cohort study or a baseline in a cohort study. These types of designs will give us information about the prevalence of outcomes or exposures; this information will be useful for designing the cohort study. However, since this is a 1-time measurement of exposure and outcome, it is difficult to derive causal relationships from cross-sectional analysis. We can estimate the prevalence of disease in cross-sectional studies. Furthermore, we will also be able to estimate the odds ratios to study the association between exposure and the outcomes in this design.

  8. Methodology Series Module 3: Cross-sectional Studies

    PubMed Central

    Setia, Maninder Singh

    2016-01-01

    Cross-sectional study design is a type of observational study design. In a cross-sectional study, the investigator measures the outcome and the exposures in the study participants at the same time. Unlike in case–control studies (participants selected based on the outcome status) or cohort studies (participants selected based on the exposure status), the participants in a cross-sectional study are just selected based on the inclusion and exclusion criteria set for the study. Once the participants have been selected for the study, the investigator follows the study to assess the exposure and the outcomes. Cross-sectional designs are used for population-based surveys and to assess the prevalence of diseases in clinic-based samples. These studies can usually be conducted relatively faster and are inexpensive. They may be conducted either before planning a cohort study or a baseline in a cohort study. These types of designs will give us information about the prevalence of outcomes or exposures; this information will be useful for designing the cohort study. However, since this is a 1-time measurement of exposure and outcome, it is difficult to derive causal relationships from cross-sectional analysis. We can estimate the prevalence of disease in cross-sectional studies. Furthermore, we will also be able to estimate the odds ratios to study the association between exposure and the outcomes in this design. PMID:27293245

  9. Cross sections and differential spectra for reactions of 2-20 MeV neutrons of /sup 27/Al

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Blann, M.; Komoto, T.T.

    1988-01-01

    This report summarizes product yields, secondary n,p and ..cap alpha.. spectra, and ..gamma..-ray spectra calculated for incident neutrons of 2-20 MeV on /sup 27/Al targets. Results are all from the code ALICE, using the version ALISO which does weighting of results for targets which are a mix of isotopes. Where natural isotopic targets are involved, yields and n,p,..cap alpha.. spectra will be reported weighted over isotopic yields. Gamma-ray spectra, however, will be reported for the most abundant isotope.

  10. Evaluation of fusion-evaporation cross-section calculations

    NASA Astrophysics Data System (ADS)

    Blank, B.; Canchel, G.; Seis, F.; Delahaye, P.

    2018-02-01

    Calculated fusion-evaporation cross sections from five different codes are compared to experimental data. The present comparison extents over a large range of nuclei and isotopic chains to investigate the evolution of experimental and calculated cross sections. All models more or less overestimate the experimental cross sections. We found reasonable agreement by using the geometrical average of the five model calculations and dividing the average by a factor of 11.2. More refined analyses are made for example for the 100Sn region.

  11. Measurement of the doubly-polarized He 3 → ( γ → , n ) p p reaction at 16.5 MeV and its implications for the GDH sum rule

    DOE PAGES

    Laskaris, G.; Yan, X.; Mueller, J. M.; ...

    2015-10-01

    We report new measurements of the double-polarized photodisintegration of 3He at an incident photon energy of 16.5 MeV, carried out at the High Intensity γ-ray Source (HIγS) facility located at Triangle Universities Nuclear Laboratory (TUNL). The spin-dependent double-differential cross sections and the contribution from the three-body channel to the Gerasimov–Drell–Hearn (GDH) integrand were extracted and compared with the state-of-the-art three-body calculations. The calculations, which include the Coulomb interaction and are in good agreement with the results of previous measurements at 12.8 and 14.7 MeV, deviate from the new cross section results at 16.5 MeV. Lastly, the GDH integrand was foundmore » to be about one standard deviation larger than the maximum value predicted by the theories.« less

  12. Experimental measurement of the 12C+16O fusion cross sections at astrophysical energies

    NASA Astrophysics Data System (ADS)

    Fang, X.; Tan, W. P.; Beard, M.; deBoer, R. J.; Gilardy, G.; Jung, H.; Liu, Q.; Lyons, S.; Robertson, D.; Setoodehnia, K.; Seymour, C.; Stech, E.; Vande Kolk, B.; Wiescher, M.; de Souza, R.; Hudan, S.; Singh, V.; Tang, X. D.; Uberseder, E.

    2018-05-01

    The total cross sections of the 12C+16O fusion have been experimentally determined at low energies to investigate the role of this reaction during late stellar evolution burning phases. A high-intensity oxygen beam was produced by the 5MV pelletron accelerator at the University of Notre Dame impinging on a thick ultra-pure graphite target. Protons and γ-rays were measured simultaneously in the center-of-mass energy range from 3.64 to 5.01 MeV, using strip silicon and HPGe detectors. Statistical model calculations were employed to interpret the experimental results. A new broad resonance-like structure is observed for the 12C+16O reaction, and a decreasing trend of its S-factor towards low energies is found.

  13. Elastic, inelastic, and 1 n transfer cross sections for the 10B+120Sn reaction

    NASA Astrophysics Data System (ADS)

    Gasques, L. R.; Freitas, A. S.; Chamon, L. C.; Oliveira, J. R. B.; Medina, N. H.; Scarduelli, V.; Rossi, E. S.; Alvarez, M. A. G.; Zagatto, V. A. B.; Lubian, J.; Nobre, G. P. A.; Padron, I.; Carlson, B. V.

    2018-03-01

    The 10B+120Sn reaction has been investigated at ELab=37.5 MeV. The cross sections for different channels, such as the elastic scattering, the excitation of the 2+ and 3-120Sn states, the excitation of the 1+ state of 10B, and the 1 n pick-up transfer, have been measured. One-step distorted-wave Born approximation and coupled-reaction-channels calculations have been performed in the context of the double-folding São Paulo potential. The effect of coupling the inelastic and transfer states on the angular distributions is discussed in the paper. In general, the theoretical calculations within the coupled-reaction-channels formalism yield a satisfactory agreement with the corresponding experimental angular distributions.

  14. Viscous Flow through Pipes of Various Cross-Sections

    ERIC Educational Resources Information Center

    Lekner, John

    2007-01-01

    An interesting variety of pipe cross-sectional shapes can be generated, for which the Navier-Stokes equations can be solved exactly. The simplest cases include the known solutions for elliptical and equilateral triangle cross-sections. Students can find pipe cross-sections from solutions of Laplace's equation in two dimensions, and then plot the…

  15. Mental Visualization of Objects from Cross-Sectional Images

    ERIC Educational Resources Information Center

    Wu, Bing; Klatzky, Roberta L.; Stetten, George D.

    2012-01-01

    We extended the classic anorthoscopic viewing procedure to test a model of visualization of 3D structures from 2D cross-sections. Four experiments were conducted to examine key processes described in the model, localizing cross-sections within a common frame of reference and spatiotemporal integration of cross sections into a hierarchical object…

  16. Determination of 20Ne(p ,γ )21Na cross sections from Ep=500 -2000 keV

    NASA Astrophysics Data System (ADS)

    Lyons, S.; Görres, J.; deBoer, R. J.; Stech, E.; Chen, Y.; Gilardy, G.; Liu, Q.; Long, A. M.; Moran, M.; Robertson, D.; Seymour, C.; Vande Kolk, B.; Wiescher, M.; Best, A.

    2018-06-01

    Background: The reaction 20Ne(p ,γ )21Na influences the nucleosynthesis of Ne, Na, and Mg isotopes while contributing to hydrogen burning in several stellar sites, such as red giants, asymptotic giant branch (AGB) stars, massive stars, and oxygen-neon (ONe) novae. In the relevant temperature range for these environments (T = 0.05-0.5 GK), the main contributions to this reaction rate are from the direct capture process as well as the high-energy tail of a subthreshold resonance in the ground-state transition at Ex = 2425 keV in the 21Na compound nucleus. Purpose: The previous measurement of this reaction reports cross sections with large uncertainties for the ground-state transition. At higher energies, where the subthreshold resonance makes a smaller contribution to the total cross section, only upper limits are provided. This work aims to reduce the uncertainty in the cross section where direct capture dominates, as well as provide cross-section data in previously unmeasured regions. Method: The 20Ne(p ,γ )21Na reaction was measured over a wide proton energy range (Ep = 0.5-2.0 MeV) at θlab = 90∘. Transitions to the ground state and to the 332 and 2425 keV excited states were observed. The primary transitions to these three bound states were utilized in an R -matrix analysis to determine the contributions of the direct capture and the subthreshold resonance to the total cross section. Results: The cross sections of the present measurements have been found to be in good agreement with the previous data at low energy. Significantly improved cross-section measurements have been obtained over the Ep = 1300-1900 keV region. The narrow resonance at Ec.m. = 1113 keV (Ex = 3544.3 keV) has also been remeasured and its strength has been found to be in good agreement with previous measurements. Conclusions: An extrapolation of the S factor of 20Ne(p ,γ )21Na has been made to low energies using the R -matrix fit. The reaction rate from the subthreshold resonance was

  17. 1 MeV, 10 kW DC electron accelerator for industrial applications

    NASA Astrophysics Data System (ADS)

    Nayak, B.; Acharya, S.; Bhattacharjee, D.; Bakhtsingh, R. I.; Rajan, R.; Sharma, D. K.; Dewangan, S.; Sharma, V.; Patel, R.; Tiwari, R.; Benarjee, S.; Srivastava, S. K.

    2016-03-01

    Several modern applications of radiation processing like medical sterilization, rubber vulcanization, polymerization, cross-linking and pollution control from thermal power stations etc. require D.C. electron accelerators of energy ranging from a few hundred keVs to few MeVs and power from a few kilowatts to hundreds of kilowatts. To match these requirements, a 3 MeV, 30 kW DC electron linac has been developed at BARC, Mumbai and current operational experience of 1 MeV, 10 kW beam power will be described in this paper. The LINAC composed mainly of Electron Gun, Accelerating Tubes, Magnets, High Voltage source and provides 10 kW beam power at the Ti beam window stably after the scanning section. The control of the LINAC is fully automated. Here Beam Optics study is carried out to reach the preferential parameters of Accelerating as well as optical elements. Beam trials have been conducted to find out the suitable operation parameters of the system.

  18. The radar cross section of dielectric disks

    NASA Technical Reports Server (NTRS)

    Levine, D. M.

    1982-01-01

    A solution is presented for the backscatter (nonstatic) radar cross section of dielectric disks of arbitrary shape, thickness and dielectric constant. The result is obtained by employing a Kirchhoff type approximation to obtain the fields inside the disk. The internal fields induce polarization and conduction currents from which the scattered fields and the radar cross section can be computed. The solution for the radar cross section obtained in this manner is shown to agree with known results in the special cases of normal incidence, thin disks and perfect conductivity. The solution can also be written as a product of the reflection coefficient of an identically oriented slab times the physical optics solution for the backscatter cross section of a perfectly conducting disk of the same shape. This result follows directly from the Kirchhoff type approximation without additional assumptions.

  19. Electron impact ionisation cross section for organoplatinum compounds

    NASA Astrophysics Data System (ADS)

    Mahato, Dibyendu; Naghma, Rahla; Alam, Mohammad Jane; Ahmad, Shabbir; Antony, Bobby

    2016-11-01

    This article reports electron impact ionisation cross sections for platinum-based drugs viz., cisplatin (H6N2Cl2Pt), carboplatin (C6H12N2O4Pt), oxaliplatin (C8H14N2O4Pt), nedaplatin (C2H8N2O3Pt) and satraplatin (C10H22ClN2O4Pt) complexes used in the cancer chemotherapy. The multi-scattering centre spherical complex optical potential formalism is used to obtain the inelastic cross section for these large molecules upon electron impact. The ionisation cross section is derived from the inelastic cross section employing complex scattering potential-ionisation contribution method. Comparison is made with previous results, where ever available and overall a reasonable agreement is observed. This is the first attempt to report total ionisation cross sections for nedaplatin and satraplatin complexes.

  20. FAST TRACK COMMUNICATION: Oscillation structures in elastic and electron capture cross sections for H+-H collisions in Debye plasmas

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Wang, J. G.; Krstic, P. S.; Janev, R. K.

    2010-10-01

    We find that the number of vibrational states in the ground potential of a H2+ molecular ion embedded in the Debye plasma and the number of Regge oscillations in the resonant charge transfer cross section of the H+ + H collision system in the plasma are quasi-conserved when the Debye radius D is larger than 1.4a0. The elastic and resonant charge transfer processes in the H+ + H collision have been studied in the 0.1 meV-100 eV collision energy range for a wide range of Debye radii using a highly accurate calculation based on the modified ab initio multireference configuration interaction code. Remarkable plasma screening effects have been found in both the molecular structure and the collision dynamics of this system. Shape resonances, Regge and glory oscillations have been found in the integral cross sections in the considered energy range even for strong interaction screening, showing their ubiquitous nature.

  1. Thermoelastic damping in microrings with circular cross-section

    NASA Astrophysics Data System (ADS)

    Li, Pu; Fang, Yuming; Zhang, Jianrun

    2016-01-01

    Predicting thermoelastic damping (TED) is crucial in the design of high Q micro-resonators. Microrings are often critical components in many micro-resonators. Some analytical models for TED in microrings have already been developed in the past. However, the previous works are limited to the microrings with rectangular cross-section. The temperature field in the rectangular cross-section is one-dimensional. This paper deals with TED in the microrings with circular cross-section. The temperature field in the circular cross-section is two-dimensional. This paper first presents a 2-D analytical model for TED in the microrings with circular cross-section. Only the two-dimensional heat conduction in the circular cross-section is considered. The heat conduction along the circumferential direction of the microring is neglected in the 2-D model. Then the 2-D model has been extended to cover the circumferential heat conduction, and a 3-D analytical model for TED has been developed. The analytical results from the present 2-D and 3-D models show good agreement with the numerical results of FEM model. The limitations of the present 2-D analytical model are assessed.

  2. Mental visualization of objects from cross-sectional images

    PubMed Central

    Wu, Bing; Klatzky, Roberta L.; Stetten, George D.

    2011-01-01

    We extended the classic anorthoscopic viewing procedure to test a model of visualization of 3D structures from 2D cross-sections. Four experiments were conducted to examine key processes described in the model, localizing cross-sections within a common frame of reference and spatiotemporal integration of cross sections into a hierarchical object representation. Participants used a hand-held device to reveal a hidden object as a sequence of cross-sectional images. The process of localization was manipulated by contrasting two displays, in-situ vs. ex-situ, which differed in whether cross sections were presented at their source locations or displaced to a remote screen. The process of integration was manipulated by varying the structural complexity of target objects and their components. Experiments 1 and 2 demonstrated visualization of 2D and 3D line-segment objects and verified predictions about display and complexity effects. In Experiments 3 and 4, the visualized forms were familiar letters and numbers. Errors and orientation effects showed that displacing cross-sectional images to a remote display (ex-situ viewing) impeded the ability to determine spatial relationships among pattern components, a failure of integration at the object level. PMID:22217386

  3. Measurement of ν¯μ and νμ charged current inclusive cross sections and their ratio with the T2K off-axis near detector

    NASA Astrophysics Data System (ADS)

    Abe, K.; Amey, J.; Andreopoulos, C.; Antonova, M.; Aoki, S.; Ariga, A.; Ashida, Y.; Ban, S.; Barbi, M.; Barker, G. J.; Barr, G.; Barry, C.; Batkiewicz, M.; Berardi, V.; Berkman, S.; Bhadra, S.; Bienstock, S.; Blondel, A.; Bolognesi, S.; Bordoni, S.; Boyd, S. B.; Brailsford, D.; Bravar, A.; Bronner, C.; Buizza Avanzini, M.; Calland, R. G.; Campbell, T.; Cao, S.; Cartwright, S. L.; Catanesi, M. G.; Cervera, A.; Chappell, A.; Checchia, C.; Cherdack, D.; Chikuma, N.; Christodoulou, G.; Coleman, J.; Collazuol, G.; Coplowe, D.; Cudd, A.; Dabrowska, A.; De Rosa, G.; Dealtry, T.; Denner, P. F.; Dennis, S. R.; Densham, C.; Di Lodovico, F.; Dolan, S.; Drapier, O.; Duffy, K. E.; Dumarchez, J.; Dunne, P.; Emery-Schrenk, S.; Ereditato, A.; Feusels, T.; Finch, A. J.; Fiorentini, G. A.; Friend, M.; Fujii, Y.; Fukuda, D.; Fukuda, Y.; Garcia, A.; Giganti, C.; Gizzarelli, F.; Golan, T.; Gonin, M.; Hadley, D. R.; Haegel, L.; Haigh, J. T.; Hansen, D.; Harada, J.; Hartz, M.; Hasegawa, T.; Hastings, N. C.; Hayashino, T.; Hayato, Y.; Hillairet, A.; Hiraki, T.; Hiramoto, A.; Hirota, S.; Hogan, M.; Holeczek, J.; Hosomi, F.; Huang, K.; Ichikawa, A. K.; Ikeda, M.; Imber, J.; Insler, J.; Intonti, R. A.; Ishida, T.; Ishii, T.; Iwai, E.; Iwamoto, K.; Izmaylov, A.; Jamieson, B.; Jiang, M.; Johnson, S.; Jonsson, P.; Jung, C. K.; Kabirnezhad, M.; Kaboth, A. C.; Kajita, T.; Kakuno, H.; Kameda, J.; Karlen, D.; Katori, T.; Kearns, E.; Khabibullin, M.; Khotjantsev, A.; Kim, H.; Kim, J.; King, S.; Kisiel, J.; Knight, A.; Knox, A.; Kobayashi, T.; Koch, L.; Koga, T.; Koller, P. P.; Konaka, A.; Kormos, L. L.; Koshio, Y.; Kowalik, K.; Kudenko, Y.; Kurjata, R.; Kutter, T.; Lagoda, J.; Lamont, I.; Lamoureux, M.; Lasorak, P.; Laveder, M.; Lawe, M.; Licciardi, M.; Lindner, T.; Liptak, Z. J.; Litchfield, R. P.; Li, X.; Longhin, A.; Lopez, J. P.; Lou, T.; Ludovici, L.; Lu, X.; Magaletti, L.; Mahn, K.; Malek, M.; Manly, S.; Maret, L.; Marino, A. D.; Martin, J. F.; Martins, P.; Martynenko, S.; Maruyama, T.; Matveev, V.; Mavrokoridis, K.; Ma, W. Y.; Mazzucato, E.; McCarthy, M.; McCauley, N.; McFarland, K. S.; McGrew, C.; Mefodiev, A.; Metelko, C.; Mezzetto, M.; Minamino, A.; Mineev, O.; Mine, S.; Missert, A.; Miura, M.; Moriyama, S.; Morrison, J.; Mueller, Th. A.; Nakadaira, T.; Nakahata, M.; Nakamura, K. G.; Nakamura, K.; Nakamura, K. D.; Nakanishi, Y.; Nakayama, S.; Nakaya, T.; Nakayoshi, K.; Nantais, C.; Nielsen, C.; Nishikawa, K.; Nishimura, Y.; Novella, P.; Nowak, J.; O'Keeffe, H. M.; Okumura, K.; Okusawa, T.; Oryszczak, W.; Oser, S. M.; Ovsyannikova, T.; Owen, R. A.; Oyama, Y.; Palladino, V.; Palomino, J. L.; Paolone, V.; Patel, N. D.; Paudyal, P.; Pavin, M.; Payne, D.; Petrov, Y.; Pickering, L.; Pinzon Guerra, E. S.; Pistillo, C.; Popov, B.; Posiadala-Zezula, M.; Poutissou, J.-M.; Pritchard, A.; Przewlocki, P.; Quilain, B.; Radermacher, T.; Radicioni, E.; Ratoff, P. N.; Rayner, M. A.; Reinherz-Aronis, E.; Riccio, C.; Rondio, E.; Rossi, B.; Roth, S.; Ruggeri, A. C.; Rychter, A.; Sakashita, K.; Sánchez, F.; Scantamburlo, E.; Scholberg, K.; Schwehr, J.; Scott, M.; Seiya, Y.; Sekiguchi, T.; Sekiya, H.; Sgalaberna, D.; Shah, R.; Shaikhiev, A.; Shaker, F.; Shaw, D.; Shiozawa, M.; Shirahige, T.; Smy, M.; Sobczyk, J. T.; Sobel, H.; Steinmann, J.; Stewart, T.; Stowell, P.; Suda, Y.; Suvorov, S.; Suzuki, A.; Suzuki, S. Y.; Suzuki, Y.; Tacik, R.; Tada, M.; Takeda, A.; Takeuchi, Y.; Tamura, R.; Tanaka, H. K.; Tanaka, H. A.; Thakore, T.; Thompson, L. F.; Tobayama, S.; Toki, W.; Tomura, T.; Tsukamoto, T.; Tzanov, M.; Vagins, M.; Vallari, Z.; Vasseur, G.; Vilela, C.; Vladisavljevic, T.; Wachala, T.; Walter, C. W.; Wark, D.; Wascko, M. O.; Weber, A.; Wendell, R.; Wilking, M. J.; Wilkinson, C.; Wilson, J. R.; Wilson, R. J.; Wret, C.; Yamada, Y.; Yamamoto, K.; Yanagisawa, C.; Yano, T.; Yen, S.; Yershov, N.; Yokoyama, M.; Yu, M.; Zalewska, A.; Zalipska, J.; Zambelli, L.; Zaremba, K.; Ziembicki, M.; Zimmerman, E. D.; Zito, M.; T2K Collaboration

    2017-09-01

    We report a measurement of cross section σ (νμ+nucleus→μ-+X ) and the first measurements of the cross section σ (ν¯μ+nucleus→μ++X ) and their ratio R (σ/(ν ¯) σ (ν ) ) at (anti) neutrino energies below 1.5 GeV. We determine the single momentum bin cross section measurements, averaged over the T2K ν ¯/ν -flux, for the detector target material (mainly carbon, oxygen, hydrogen and copper) with phase space restricted laboratory frame kinematics of θμ<3 2 ° and pμ>500 MeV /c . The results are σ (ν ¯ )=(0.900 ±0.029 (stat ) ±0.088 (syst ) ) ×10-39 and σ (ν )=(2.41 ±0.022 (stat ) ±0.231 (syst ) ) ×10-39 in units of cm2 /nucleon and R (σ/(ν ¯ ) σ (ν ) ) =0.373 ±0.012 (stat ) ±0.015 (syst ) .

  4. Cross-Section Measurements in the Fast Neutron Energy Range

    NASA Astrophysics Data System (ADS)

    Plompen, Arjan

    2006-04-01

    Generation IV focuses research for advanced nuclear reactors on six concepts. Three of these concepts, the lead, gas and sodium fast reactors (LFR, GFR and SFR) have fast neutron spectra, whereas a fourth, the super-critical water reactor (SCWR), can be configured to have a fast spectrum. Such fast neutron spectra are essential to meet the sustainability objective of GenIV. Nuclear data requirements for GenIV concepts will therefore emphasize the energy region from about 1 keV to 10 MeV. Here, the potential is illustrated of the GELINA neutron time-of-flight facility and the Van de Graaff laboratory at IRMM to measure the relevant nuclear data in this energy range: the total, capture, fission and inelastic-scattering cross sections. In particular, measurement results will be shown for lead and bismuth inelastic scattering for which the need was recently expressed in a quantitative way by Aliberti et al. for Accelerator Driven Systems. Even without completion of the quantitative assessment of the data needs for GenIV concepts at ANL it is clear that this particular effort is of relevance to LFR system studies.

  5. Proton-Nucleus Total Cross Sections in Coupled-Channel Approach

    NASA Technical Reports Server (NTRS)

    Tripathi, R. K.; Wilson, John W.; Cucinotta, Francis A.

    2000-01-01

    Recently, nucleon-nucleon (N-N) cross sections in the medium have been extracted directly from experiment. The in-medium N-N cross sections form the basic ingredients of several heavy-ion scattering approaches including the coupled-channel approach developed at the Langley Research Center. In the present study the ratio of the real to the imaginary part of the two-body scattering amplitude in the medium was investigated. These ratios are used in combination with the in-medium N-N cross sections to calculate total proton-nucleus cross sections. The agreement is excellent with the available experimental data. These cross sections are needed for the radiation risk assessment of space missions.

  6. CROSS DRIVE BETWEEN SECTION A (RIGHT) AND SECTION B (LEFT), ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CROSS DRIVE BETWEEN SECTION A (RIGHT) AND SECTION B (LEFT), WITH FLAGPOLE AND COMMITTAL SHELTER AT CENTER BACKGROUND. VIEW TO NORTHWEST. - Knoxville National Cemetery, 939 Tyson Street, Northwest, Knoxville, Knox County, TN

  7. New cross sections for H on H2 collisional transitions

    NASA Astrophysics Data System (ADS)

    Zou, Qianxia

    2011-12-01

    The cross section for H on H2 collisions is important for astrophysics as well as our understanding of the simple chemical systems. This is the simplest atom-molecule cross section. With a new H3 potential surface by Mielke et al., we have modified the ABC code by Skouteris, Castillo and Manolopoulos to calculate new cross sections. These cross sections are compared to previous cross section calculations.

  8. 242Pu absolute neutron-capture cross section measurement

    NASA Astrophysics Data System (ADS)

    Buckner, M. Q.; Wu, C. Y.; Henderson, R. A.; Bucher, B.; Chyzh, A.; Bredeweg, T. A.; Baramsai, B.; Couture, A.; Jandel, M.; Mosby, S.; O'Donnell, J. M.; Ullmann, J. L.

    2017-09-01

    The absolute neutron-capture cross section of 242Pu was measured at the Los Alamos Neutron Science Center using the Detector for Advanced Neutron-Capture Experiments array along with a compact parallel-plate avalanche counter for fission-fragment detection. During target fabrication, a small amount of 239Pu was added to the active target so that the absolute scale of the 242Pu(n,γ) cross section could be set according to the known 239Pu(n,f) resonance at En,R = 7.83 eV. The relative scale of the 242Pu(n,γ) cross section covers four orders of magnitude for incident neutron energies from thermal to ≈ 40 keV. The cross section reported in ENDF/B-VII.1 for the 242Pu(n,γ) En,R = 2.68 eV resonance was found to be 2.4% lower than the new absolute 242Pu(n,γ) cross section.

  9. Unifying measurement of 239Pu(n ,γ ) in the keV to MeV energy regime

    NASA Astrophysics Data System (ADS)

    Mosby, S.; Bredeweg, T. A.; Couture, A.; Jandel, M.; Kawano, T.; Ullmann, J. L.; Henderson, R. A.; Wu, C. Y.

    2018-04-01

    A single, unifying measurement of the 239Pu capture cross section from 1 keV to 1.3 MeV has been performed for the first time using the Detector for Advanced Neutron Capture Experiments (DANCE) at the Los Alamos Neutron Science Center (LANSCE). The experimental method combines a prior experiment's characterization of prompt fission γ rays in conjunction with a fission tagging detector with a separate experiment using a thick 239Pu sample to extract the neutron capture cross section in ratio to 239Pu(n ,f ) . We have made new predictions of the capture cross section taking into account recent results for the M 1 scissors mode present in other actinides. The results show deviations from current evaluations which are 30% higher at the highest energies, and will be used to improve calculations relevant for several applications.

  10. Simulation study of neutron production in thick beryllium targets by 35 MeV and 50.5 MeV proton beams

    NASA Astrophysics Data System (ADS)

    Shin, Jae Won; Park, Tae-Sun

    2017-09-01

    A data-driven nuclear model dedicated to an accurate description of neutron productions in beryllium targets bombarded by proton beams is developed as a custom development that can be used as an add-on to GEANT4 code. The developed model, G4Data(Endf7.1), takes as inputs the total and differential cross section data of ENDF/B-VII.1 for not only the charge-exchange 9Be(p,n)9B reaction which produces discrete neutrons but also the nuclear reactions relevant for the production of continuum neutrons such as 9Be(p,pn)8Be and 9Be(p,n α) 5Li . In our benchmarking simulations for two experiments with 35 MeV and 50.5 MeV proton beams impinged on 1.16 and 1.05 cm thick beryllium targets, respectively, we find that the G4Data(Endf7.1) model can reproduce both the total amounts and the spectral shapes of the measured neutron yield data in a satisfactory manner, while all the considered hadronic models of GEANT4 cannot.

  11. Elastic, inelastic, and 1 n transfer cross sections for the B 10 + Sn 120 reaction

    DOE PAGES

    Gasques, L. R.; Freitas, A. S.; Chamon, L. C.; ...

    2018-03-30

    The 10B+ 120Sn reaction has been investigated at E Lab=37.5 MeV. The cross sections for different channels, such as the elastic scattering, the excitation of the 2 + and 3 -120Sn states, the excitation of the 1 + state of 10B, and the 1n pick-up transfer, have been measured. One-step distorted-wave Born approximation and coupled-reaction-channels calculations have been performed in the context of the double-folding São Paulo potential. Here, the effect of coupling the inelastic and transfer states on the angular distributions is discussed in the paper. In general, the theoretical calculations within the coupled-reaction-channels formalism yield a satisfactory agreementmore » with the corresponding experimental angular distributions.« less

  12. Elastic, inelastic, and 1 n transfer cross sections for the B 10 + Sn 120 reaction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gasques, L. R.; Freitas, A. S.; Chamon, L. C.

    The 10B+ 120Sn reaction has been investigated at E Lab=37.5 MeV. The cross sections for different channels, such as the elastic scattering, the excitation of the 2 + and 3 -120Sn states, the excitation of the 1 + state of 10B, and the 1n pick-up transfer, have been measured. One-step distorted-wave Born approximation and coupled-reaction-channels calculations have been performed in the context of the double-folding São Paulo potential. Here, the effect of coupling the inelastic and transfer states on the angular distributions is discussed in the paper. In general, the theoretical calculations within the coupled-reaction-channels formalism yield a satisfactory agreementmore » with the corresponding experimental angular distributions.« less

  13. 94 Mo(γ,n) and 90Zr(γ,n) cross-section measurements towards understanding the origin of p-nuclei

    NASA Astrophysics Data System (ADS)

    Meekins, E.; Banu, A.; Karwowski, H.; Silano, J.; Zimmerman, W.; Muller, J.; Rich, G.; Bhike, M.; Tornow, W.; McClesky, M.; Travaglio, C.

    2014-09-01

    The nucleosynthesis beyond iron of the rarest stable isotopes in the cosmos, the so-called p-nuclei, is one of the forefront topics in nuclear astrophysics. Recently, a stellar source was found that, for the first time, was able to produce both light and heavy p-nuclei almost at the same level as 56Fe, including the most debated 92,94Mo and 96,98Ru; it was also found that there is an important contribution from the p-process nucleosynthesis to the neutron magic nucleus 90Zr. We focus here on constraining the origin of p-nuclei through nuclear physics by studying two key astrophysical photoneutron reaction cross sections for 94Mo(γ,n) and 90Zr(γ,n). Their energy dependencies were measured using quasi-monochromatic photon beams from Duke University's High Intensity Gamma-ray Source facility at the respective neutron threshold energies up to 18 MeV. Preliminary results of these experimental cross sections will be presented along with their comparison to predictions by a statistical model based on the Hauser-Feshbach formalism implemented in codes like TALYS and SMARAGD. The nucleosynthesis beyond iron of the rarest stable isotopes in the cosmos, the so-called p-nuclei, is one of the forefront topics in nuclear astrophysics. Recently, a stellar source was found that, for the first time, was able to produce both light and heavy p-nuclei almost at the same level as 56Fe, including the most debated 92,94Mo and 96,98Ru; it was also found that there is an important contribution from the p-process nucleosynthesis to the neutron magic nucleus 90Zr. We focus here on constraining the origin of p-nuclei through nuclear physics by studying two key astrophysical photoneutron reaction cross sections for 94Mo(γ,n) and 90Zr(γ,n). Their energy dependencies were measured using quasi-monochromatic photon beams from Duke University's High Intensity Gamma-ray Source facility at the respective neutron threshold energies up to 18 MeV. Preliminary results of these experimental cross

  14. Location of multiparticle-multihole strength in 16N via the 3-particle transfer reaction 13C(α, p) 16N at 118 MeV

    NASA Astrophysics Data System (ADS)

    Andrews, P. R.; Shute, G. G.; Spicer, B. M.; Collins, S. F.; Officer, V. C.; Wastell, J. M.; Nann, H.; Devins, D. W.; LI, Qingli; Jones, W. P.; Olmer, C.; Bacher, A. D.; Emery, G. T.

    1986-11-01

    Differential cross sections were measured for the 13C(α, p) 16N reaction at Eα = 118 MeV for an excitation energy range up to 14.5 MeV. Zero-range distorted wave Born approximation (DWBA) calculations were performed using microscopic form factors. Spin-parity assignments are suggested for states at 11.21 MeV (6 -) and 11.81 MeV (7 -) on the basis of Bansal-French-Zamick weak coupling calculations and DWBA calculations. Arguments from 16O(e, e'), 16O(p, p') and the present experiment are given relating to the location of Jπ = 4 -, T = 1 strength in 16N.

  15. Evaluation of the radiation hazard for ion-beam analysis with MeV external proton beams (X-IBA)

    NASA Astrophysics Data System (ADS)

    Hofsäss, Hans

    2018-07-01

    MeV ion beams which are extracted into air or He atmosphere are used in many labs for proton-induced X-ray emission (PIXE), proton induced gamma ray emission (PIGE) or Rutherford backscattering (RBS) to analyze samples which are difficult or impossible to handle in vacuum. When MeV proton beams are extracted into air through thin Kapton foils or nowadays thin silicon nitride membranes, the protons will interact with air, as well as elements present in the analyzed samples. Typically the range of MeV protons in air is several cm, in Helium atmosphere several 10 cm and in human skin around 100 μm. Besides the severe radiation hazard in case of a direct exposure of skin with protons, there are a manifold of nuclear reactions or inelastic proton scattering processes which may cause activation of air and target materials but also prompt radiation. The radiation hazard associated with the direct and scattered beam, nuclear reaction products and radionuclide production in air have been discussed in a publication by Doyle et al. in 1991 which was used as a reference in several later publications. I have reevaluated the radiation hazards for external proton beams with up to 4.5 MeV using proton reaction cross sections taken from the JANIS book of proton induced cross sections. The radionuclide production in air is about 3 orders of magnitude lower compared to values given in the 1991 publication. Radionuclide production as well as generation of prompt alpha, gamma and neutron radiation in target materials for elements up to molybdenum is also evaluated.

  16. A method for calculating proton-nucleus elastic cross-sections

    NASA Technical Reports Server (NTRS)

    Tripathi, R. K.; Wilson, J. W.; Cucinotta, F. A.

    2002-01-01

    Recently [Nucl. Instr. and Meth. B 145 (1998) 277; Extraction of in-medium nucleon-nucleon amplitude from experiment, NASA-TP, 1998], we developed a method of extracting nucleon-nucleon (N-N) cross-sections in the medium directly from experiment. The in-medium N-N cross-sections form the basic ingredients of several heavy-ion scattering approaches including the coupled-channel approach developed at the NASA Langley Research Center. We investigated [Proton-nucleus total cross-sections in coupled-channel approach, NASA/TP, 2000; Nucl. Instr. and Meth. B 173-174 (2001) 391] the ratio of real to imaginary part of the two body scattering amplitude in the medium. These ratios are used in combination with the in-medium N-N cross-sections to calculate proton-nucleus elastic cross-sections. The agreement is excellent with the available experimental data. These cross-sections are needed for the radiation risk assessment of space missions. c2002 Elsevier Science B.V. All rights reserved.

  17. Total and partial photoneutron cross sections for Pb isotopes

    NASA Astrophysics Data System (ADS)

    Kondo, T.; Utsunomiya, H.; Goriely, S.; Daoutidis, I.; Iwamoto, C.; Akimune, H.; Okamoto, A.; Yamagata, T.; Kamata, M.; Itoh, O.; Toyokawa, H.; Lui, Y.-W.; Harada, H.; Kitatani, F.; Hilaire, S.; Koning, A. J.

    2012-07-01

    Using quasimonochromatic laser-Compton scattering γ rays, total photoneutron cross sections were measured for 206,207,208Pb near neutron threshold with a high-efficiency 4π neutron detector. Partial E1 and M1 photoneutron cross sections along with total cross sections were determined for 207,208Pb at four energies near threshold by measuring anisotropies in photoneutron emission with linearly polarized γ rays. The E1 strength dominates over the M1 strength in the neutron channel where E1 photoneutron cross sections show extra strength of the pygmy dipole resonance in 207,208Pb near the neutron threshold corresponding to 0.32%-0.42% of the Thomas-Reiche-Kuhn sum rule. Several μN2 units of B(M1)↑ strength were observed in 207,208Pb just above neutron threshold, which correspond to an M1 cross section less than 10% of the total photoneutron cross section.

  18. 5 MeV Mott polarimeter for rapid precise electron beam polarization measurements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Price, J.S.; Poelker, B.M.; Sinclair, C.K.

    1997-11-01

    Low energy (E{sub k} = 100 keV) Mott scattering polarimeters are ill-suited to support operations foreseen for the polarized electron injector at Jefferson Lab. One solution is to measure the polarization at 5 MeV where multiple and plural scattering are unimportant and precision beam monitoring is straightforward. The higher injector beam current offsets the lower cross-sections; measured rates scale to 1 kHz/{mu}A with a 1 {mu}m thick gold target foil.

  19. Cross-section fluctuations in chaotic scattering systems.

    PubMed

    Ericson, Torleif E O; Dietz, Barbara; Richter, Achim

    2016-10-01

    Exact analytical expressions for the cross-section correlation functions of chaotic scattering systems have hitherto been derived only under special conditions. The objective of the present article is to provide expressions that are applicable beyond these restrictions. The derivation is based on a statistical model of Breit-Wigner type for chaotic scattering amplitudes which has been shown to describe the exact analytical results for the scattering (S)-matrix correlation functions accurately. Our results are given in the energy and in the time representations and apply in the whole range from isolated to overlapping resonances. The S-matrix contributions to the cross-section correlations are obtained in terms of explicit irreducible and reducible correlation functions. Consequently, the model can be used for a detailed exploration of the key features of the cross-section correlations and the underlying physical mechanisms. In the region of isolated resonances, the cross-section correlations contain a dominant contribution from the self-correlation term. For narrow states the self-correlations originate predominantly from widely spaced states with exceptionally large partial width. In the asymptotic region of well-overlapping resonances, the cross-section autocorrelation functions are given in terms of the S-matrix autocorrelation functions. For inelastic correlations, in particular, the Ericson fluctuations rapidly dominate in that region. Agreement with known analytical and experimental results is excellent.

  20. Shuttle orbiter radar cross-sectional analysis

    NASA Technical Reports Server (NTRS)

    Cooper, D. W.; James, R.

    1979-01-01

    Theoretical and model simulation studies on signal to noise levels and shuttle radar cross section are described. Pre-mission system calibrations, system configuration, and postmission system calibration of the tracking radars are described. Conversion of target range, azimuth, and elevation into radar centered east north vertical position coordinates are evaluated. The location of the impinging rf energy with respect to the target vehicles body axis triad is calculated. Cross section correlation between the two radars is presented.

  1. Temperature-dependent absorption cross sections for hydrogen peroxide vapor

    NASA Technical Reports Server (NTRS)

    Nicovich, J. M.; Wine, P. H.

    1988-01-01

    Relative absorption cross sections for hydrogen peroxide vapor were measured over the temperature ranges 285-381 K for lambda = 230 nm-295 nm and 300-381 K for lambda = 193 nm-350 nm. The well established 298 K cross sections at 202.6 and 228.8 nm were used as an absolute calibration. A significant temperature dependence was observed at the important tropospheric photolysis wavelengths lambda over 300 nm. Measured cross sections were extrapolated to lower temperatures, using a simple model which attributes the observed temperature dependence to enhanced absorption by molecules possessing one quantum of O-O stretch vibrational excitation. Upper tropospheric photodissociation rates calculated using the extrapolated cross sections are about 25 percent lower than those calculated using currently recommended 298 K cross sections.

  2. Electron impact ionization cross sections of beryllium-tungsten clusters*

    NASA Astrophysics Data System (ADS)

    Sukuba, Ivan; Kaiser, Alexander; Huber, Stefan E.; Urban, Jan; Probst, Michael

    2016-01-01

    We report calculated electron impact ionization cross sections (EICSs) of beryllium-tungsten clusters, BenW with n = 1,...,12, from the ionization threshold to 10 keV using the Deutsch-Märk (DM) and the binary-encounter-Bethe (BEB) formalisms. The positions of the maxima of DM and BEB cross sections are mostly close to each other. The DM cross sections are more sensitive with respect to the cluster size. For the clusters smaller than Be4W they yield smaller cross sections than BEB and vice versa larger cross sections than BEB for clusters larger than Be6W. The maximum cross section values for the singlet-spin groundstate clusters range from 7.0 × 10-16 cm2 at 28 eV (BeW) to 54.2 × 10-16 cm2 at 43 eV (Be12W) for the DM cross sections and from 13.5 × 10-16 cm2 at 43 eV (BeW) to 38.9 × 10-16 cm2 at 43 eV (Be12W) for the BEB cross sections. Differences of the EICSs in different isomers and between singlet and triplet states are also explored. Both the DM and BEB cross sections could be fitted perfectly to a simple expression used in modeling and simulation codes in the framework of nuclear fusion research. Contribution to the Topical Issue "Atomic Cluster Collisions (7th International Symposium)", edited by Gerardo Delgado Barrio, Andrey Solov'Yov, Pablo Villarreal, Rita Prosmiti.Supplementary material in the form of one pdf file available from the Journal web page at http://dx.doi.org/10.1140/epjd/e2015-60583-7

  3. The Differential Cross Section and Λ Recoil Polarization from γδ -> Κ0(ρ)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Compton, Nicholas; Thomas Jefferson National Accelerator Facility

    2017-04-30

    Presented is the analysis of the differential cross section and Λ recoil polarization from the reaction γδ -> Κ0(ρ). This work measured these observables over beam energies from 0.90 GeV to 3.0 GeV. These measurements are the first in this channel to cover such a wide range of energies. The data were taken using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Laboratory (JLAB) along with a tagged photon beam. This analysis was completed by identifying events of interest that decayed into the final state topology of π-π+,π-&rho'(ρ). Through conservation of energy and momentum, the Κ0, Λ and missing massmore » of the spectator proton were reconstructed. Utilizing the same analysis techniques, the observables were measured on two different experiments with good agreement. Photoproduction of strange mesons from the neutron are difficult to measure, consequently there are only a few measurements of this kind. Despite that, these reactions supply essential complementary data to those on the proton. The differential cross sections and the recoil polarization extracted, span the region where new nucleon resonances have been found from studies of the reaction γρ -> Κ+Λ. Comparisons between the Κ+Λ and Κ0Λ cross section demonstrate that possible interference terms near 1900 MeV are less pronounced in the latter. This unexpected result inspired a partial wave analyses (PWA) to be fitted to the data. The fit solution shows that this measurement fostered an improvement on the knowledge of observed resonance parameters, necessary to understanding these excited states. The study of nucleon resonances is a key motivating factor since the resonance masses can be calculated from the theory of the strong nuclear force, called quantum chromodynamics, or QCD.« less

  4. Absorption Cross-Sections of Sodium Diatomic Molecules

    NASA Technical Reports Server (NTRS)

    Fong, Zeng-Shevan

    1985-01-01

    The absorption cross sections of sodium dimers were studied using a heat pipe over operating in the non-heat-pipe mode. Three wavelength regions were observed. They are in the red, the green-blue, and the near ultraviolet regions. The absorption cross section depends on the wavelength of the incident light. Representative peak values for the v"=0 progression in the red and green-blue regions are 2.59 A sup 2 (average value) and 11.77 A sup 2 (T sub ave=624 K). The value for the C greater than X transitions is several tenths A sup 2. The cross sections were measured from absorption spectra taken as a function of temperature.

  5. Single-level resonance parameters fit nuclear cross-sections

    NASA Technical Reports Server (NTRS)

    Drawbaugh, D. W.; Gibson, G.; Miller, M.; Page, S. L.

    1970-01-01

    Least squares analyses of experimental differential cross-section data for the U-235 nucleus have yielded single level Breit-Wigner resonance parameters that fit, simultaneously, three nuclear cross sections of capture, fission, and total.

  6. Electromagnetic fission of238U at 600 and 1000 MeV per nucleon

    NASA Astrophysics Data System (ADS)

    Rubehn, Th.; Müller, W. F. J.; Bassini, R.; Begemann-Blaich, M.; Blaich, Th.; Ferrero, A.; Groß, C.; Imme, G.; Iori, I.; Kunde, G. J.; Kunze, W. D.; Lindenstruth, V.; Lynen, U.; Möhlenkamp, T.; Moretto, L. G.; Ocker, B.; Pochodzalla, J.; Raciti, G.; Reito, S.; Sann, H.; Schüttauf, A.; Seidel, W.; Serfling, V.; Trautmann, W.; Trzcinski, A.; Verde, G.; Wörner, A.; Zude, E.; Zwieglinski, B.

    1995-06-01

    Electromagnetic fission of238U projectiles at E/A =600 and 1000 MeV was studied with the ALADIN spectrometer at the heavy-ion synchrotron SIS. Seven different targets (Be, C, Al, Cu, In, Au and U) were used. By considering only those fission events where the two charges added up to 92, most of the nuclear interactions were excluded. The nuclear contributions to the measured fission cross sections were determined by extrapolating from beryllium to the heavier targets with the concept of factorization. The obtained cross sections for electromagnetic fission are well reproduced by extended Weizsäcker-Williams calculations which include E1 and E2 excitations. The asymmetry of the fission fragments' charge distribution gives evidence for the excitation of the double giant-dipole resonance in uranium.

  7. Scaling Cross Sections for Ion-atom Impact Ionization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Igor D. Kaganovich; Edward Startsev; Ronald C. Davidson

    2003-06-06

    The values of ion-atom ionization cross sections are frequently needed for many applications that utilize the propagation of fast ions through matter. When experimental data and theoretical calculations are not available, approximate formulas are frequently used. This paper briefly summarizes the most important theoretical results and approaches to cross section calculations in order to place the discussion in historical perspective and offer a concise introduction to the topic. Based on experimental data and theoretical predictions, a new fit for ionization cross sections is proposed. The range of validity and accuracy of several frequently used approximations (classical trajectory, the Born approximation,more » and so forth) are discussed using, as examples, the ionization cross sections of hydrogen and helium atoms by various fully stripped ions.« less

  8. Neutrino Cross Sections

    NASA Astrophysics Data System (ADS)

    Fields, Laura

    2014-03-01

    The next generation of neutrino oscillation experiments aims to answer many interesting questions such as whether there is CP violation in the neutrino sector and whether sterile neutrinos exist. These esperiments will require high precision cross section measurements of various neutrino and antineutrino channels. Results and prosepects for such measurements from the MINERvA, MiniBooNE, T2K and ArgoNeuT collaborations will be reviewed.

  9. NNLO jet cross sections by subtraction

    NASA Astrophysics Data System (ADS)

    Somogyi, G.; Bolzoni, P.; Trócsányi, Z.

    2010-08-01

    We report on the computation of a class of integrals that appear when integrating the so-called iterated singly-unresolved approximate cross section of the NNLO subtraction scheme of Refs. [G. Somogyi, Z. Trócsányi, and V. Del Duca, JHEP 06, 024 (2005), arXiv:hep-ph/0502226; G. Somogyi and Z. Trócsányi, (2006), arXiv:hep-ph/0609041; G. Somogyi, Z. Trócsányi, and V. Del Duca, JHEP 01, 070 (2007), arXiv:hep-ph/0609042; G. Somogyi and Z. Trócsányi, JHEP 01, 052 (2007), arXiv:hep-ph/0609043] over the factorised phase space of unresolved partons. The integrated approximate cross section itself can be written as the product of an insertion operator (in colour space) times the Born cross section. We give selected results for the insertion operator for processes with two and three hard partons in the final state.

  10. Neutron capture cross sections of Kr

    NASA Astrophysics Data System (ADS)

    Fiebiger, Stefan; Baramsai, Bayarbadrakh; Couture, Aaron; Krtička, Milan; Mosby, Shea; Reifarth, René; O'Donnell, John; Rusev, Gencho; Ullmann, John; Weigand, Mario; Wolf, Clemens

    2018-01-01

    Neutron capture and β- -decay are competing branches of the s-process nucleosynthesis path at 85Kr [1], which makes it an important branching point. The knowledge of its neutron capture cross section is therefore essential to constrain stellar models of nucleosynthesis. Despite its importance for different fields, no direct measurement of the cross section of 85Kr in the keV-regime has been performed. The currently reported uncertainties are still in the order of 50% [2, 3]. Neutron capture cross section measurements on a 4% enriched 85Kr gas enclosed in a stainless steel cylinder were performed at Los Alamos National Laboratory (LANL) using the Detector for Advanced Neutron Capture Experiments (DANCE). 85Kr is radioactive isotope with a half life of 10.8 years. As this was a low-enrichment sample, the main contaminants, the stable krypton isotopes 83Kr and 86Kr, were also investigated. The material was highly enriched and contained in pressurized stainless steel spheres.

  11. ANITA-IEAF activation code package - updating of the decay and cross section data libraries and validation on the experimental data from the Karlsruhe Isochronous Cyclotron

    NASA Astrophysics Data System (ADS)

    Frisoni, Manuela

    2017-09-01

    ANITA-IEAF is an activation package (code and libraries) developed in the past in ENEA-Bologna in order to assess the activation of materials exposed to neutrons with energies greater than 20 MeV. An updated version of the ANITA-IEAF activation code package has been developed. It is suitable to be applied to the study of the irradiation effects on materials in facilities like the International Fusion Materials Irradiation Facility (IFMIF) and the DEMO Oriented Neutron Source (DONES), in which a considerable amount of neutrons with energies above 20 MeV is produced. The present paper summarizes the main characteristics of the updated version of ANITA-IEAF, able to use decay and cross section data based on more recent evaluated nuclear data libraries, i.e. the JEFF-3.1.1 Radioactive Decay Data Library and the EAF-2010 neutron activation cross section library. In this paper the validation effort related to the comparison between the code predictions and the activity measurements obtained from the Karlsruhe Isochronous Cyclotron is presented. In this integral experiment samples of two different steels, SS-316 and F82H, pure vanadium and a vanadium alloy, structural materials of interest in fusion technology, were activated in a neutron spectrum similar to the IFMIF neutron field.

  12. Unifying measurement of Pu 239 ( n , γ ) in the keV to MeV energy regime

    DOE PAGES

    Mosby, S.; Bredeweg, T. A.; Couture, A.; ...

    2018-04-23

    A single, unifying measurement of the 239Pu capture cross section from 1 keV to 1.3 MeV has been performed for the first time using the Detector for Advanced Neutron Capture Experiments (DANCE) at the Los Alamos Neutron Science Center (LANSCE). The experimental method combines a prior experiment's characterization of prompt fission γ rays in conjunction with a fission tagging detector with a separate experiment using a thick 239Pu sample to extract the neutron capture cross section in ratio to 239Pu (n, f). We have made new predictions of the capture cross section taking into account recent results for the M1more » scissors mode present in other actinides. The results show deviations from current evaluations which are 30% higher at the highest energies, and will be used to improve calculations relevant for several applications.« less

  13. Parameterized Cross Sections for Pion Production in Proton-Proton Collisions

    NASA Technical Reports Server (NTRS)

    Blattnig, Steve R.; Swaminathan, Sudha R.; Kruger, Adam T.; Ngom, Moussa; Norbury, John W.; Tripathi, R. K.

    2000-01-01

    An accurate knowledge of cross sections for pion production in proton-proton collisions finds wide application in particle physics, astrophysics, cosmic ray physics, and space radiation problems, especially in situations where an incident proton is transported through some medium and knowledge of the output particle spectrum is required when given the input spectrum. In these cases, accurate parameterizations of the cross sections are desired. In this paper much of the experimental data are reviewed and compared with a wide variety of different cross section parameterizations. Therefore, parameterizations of neutral and charged pion cross sections are provided that give a very accurate description of the experimental data. Lorentz invariant differential cross sections, spectral distributions, and total cross section parameterizations are presented.

  14. Universal Parameterization of Absorption Cross Sections

    NASA Technical Reports Server (NTRS)

    Tripathi, R. K.; Cucinotta, Francis A.; Wilson, John W.

    1999-01-01

    Our prior nuclear absorption cross sections model is extended for light systems (A less than or equal to 4) where either both projectile and target are light particles or one is a light particle and the other is a medium or heavy nucleus. The agreement with experiment is excellent for these cases as well. Present work in combination with our original model provides a comprehensive picture of absorption cross sections for light, medium, and heavy systems, a very valuable input for radiation protection studies.

  15. Measurement of 235U(n,n'γ) and 235U(n,2nγ) reaction cross sections

    NASA Astrophysics Data System (ADS)

    Kerveno, M.; Thiry, J. C.; Bacquias, A.; Borcea, C.; Dessagne, P.; Drohé, J. C.; Goriely, S.; Hilaire, S.; Jericha, E.; Karam, H.; Negret, A.; Pavlik, A.; Plompen, A. J. M.; Romain, P.; Rouki, C.; Rudolf, G.; Stanoiu, M.

    2013-02-01

    The design of generation IV nuclear reactors and the studies of new fuel cycles require knowledge of the cross sections of various nuclear reactions. Our research is focused on (n,xnγ) reactions occurring in these new reactors. The aim is to measure unknown cross sections and to reduce the uncertainty on present data for reactions and isotopes of interest for transmutation or advanced reactors. The present work studies the 235U(n,n'γ) and 235U(n,2nγ) reactions in the fast neutron energy domain (up to 20 MeV). The experiments were performed with the Geel electron linear accelerator GELINA, which delivers a pulsed white neutron beam. The time characteristics enable measuring neutron energies with the time-of-flight (TOF) technique. The neutron induced reactions [in this case inelastic scattering and (n,2n) reactions] are identified by on-line prompt γ spectroscopy with an experimental setup including four high-purity germanium (HPGe) detectors. A fission ionization chamber is used to monitor the incident neutron flux. The experimental setup and analysis methods are presented and the model calculations performed with the TALYS-1.2 code are discussed.

  16. Spin distributions and cross sections of evaporation residues in the 28Si+176Yb reaction

    NASA Astrophysics Data System (ADS)

    Sudarshan, K.; Tripathi, R.; Sodaye, S.; Sharma, S. K.; Pujari, P. K.; Gehlot, J.; Madhavan, N.; Nath, S.; Mohanto, G.; Mukul, I.; Jhingan, A.; Mazumdar, I.

    2017-02-01

    Background: Non-compound-nucleus fission in the preactinide region has been an active area of investigation in the recent past. Based on the measurements of fission-fragment mass distributions in the fission of 202Po, populated by reactions with varying entrance channel mass asymmetry, the onset of non-compound-nucleus fission was proposed to be around ZpZt˜1000 [Phys. Rev. C 77, 024606 (2008), 10.1103/PhysRevC.77.024606], where Zp and Zt are the projectile and target proton numbers, respectively. Purpose: The present paper is aimed at the measurement of cross sections and spin distributions of evaporation residues in the 28Si+176Yb reaction (ZpZt=980 ) to investigate the fusion hindrance which, in turn, would give information about the contribution from non-compound-nucleus fission in this reaction. Method: Evaporation-residue cross sections were measured in the beam energy range of 129-166 MeV using the hybrid recoil mass analyzer (HYRA) operated in the gas-filled mode. Evaporation-residue cross sections were also measured by the recoil catcher technique followed by off-line γ -ray spectrometry at few intermediate energies. γ -ray multiplicities of evaporation residues were measured to infer about their spin distribution. The measurements were carried out using NaI(Tl) detector-based 4π-spin spectrometer from the Tata Institute of Fundamental Research, Mumbai, coupled to the HYRA. Results: Evaporation-residue cross sections were significantly lower compared to those calculated using the statistical model code pace2 [Phys. Rev. C 21, 230 (1980), 10.1103/PhysRevC.21.230] with the coupled-channel fusion model code ccfus [Comput. Phys. Commun. 46, 187 (1987), 10.1016/0010-4655(87)90045-2] at beam energies close to the entrance channel Coulomb barrier. At higher beam energies, experimental cross sections were close to those predicted by the model. Average γ -ray multiplicities or angular momentum values of evaporation residues were in agreement with the

  17. Measurement of charge- and mass-changing cross sections for 4He+12C collisions in the energy range 80-220 MeV/u for applications in ion beam therapy

    NASA Astrophysics Data System (ADS)

    Horst, Felix; Schuy, Christoph; Weber, Uli; Brinkmann, Kai-Thomas; Zink, Klemens

    2017-08-01

    4He ions are considered to be used for hadron radiotherapy due to their favorable physical and radiobiological properties. For an accurate dose calculation the fragmentation of the primary 4He ions occurring as a result of nuclear collisions must be taken into account. Therefore precise nuclear reaction models need to be implemented in the radiation transport codes used for dose calculation. A fragmentation experiment using thin graphite targets was conducted at the Heidelberg Ion Beam Therapy Center (HIT) to obtain new and precise 4He-nucleus cross section data in the clinically relevant energy range. Measured values for the charge-changing cross section, mass-changing cross section, as well as the inclusive 3He production cross section for 4He+12C collisions at energies between 80 and 220 MeV /u are presented. These data are compared to the 4He-nucleus reaction model by DeVries and Peng as well as to the parametrizations by Tripathi et al. and by Cucinotta et al., which are implemented in the treatment planning code trip98 and several other radiation transport codes.

  18. Novel Cosmic-Ray Electron and Positron Constraints on MeV Dark Matter Particles.

    PubMed

    Boudaud, Mathieu; Lavalle, Julien; Salati, Pierre

    2017-07-14

    MeV dark matter (DM) particles annihilating or decaying to electron-positron pairs cannot, in principle, be observed via local cosmic-ray (CR) measurements because of the shielding solar magnetic field. In this Letter, we take advantage of spacecraft Voyager 1's capacity for detecting interstellar CRs since it crossed the heliopause in 2012. This opens up a new avenue to probe DM in the sub-GeV energy/mass range that we exploit here for the first time. From a complete description of the transport of electrons and positrons at low energy, we derive predictions for both the secondary astrophysical background and the pair production mechanisms relevant to DM annihilation or decay down to the MeV mass range. Interestingly, we show that reacceleration may push positrons up to energies larger than the DM particle mass. We combine the constraints from the Voyager and AMS-02 data to get novel limits covering a very extended DM particle mass range, from MeV to TeV. In the MeV mass range, our limits reach annihilation cross sections of order ⟨σv⟩∼10^{-28}  cm^{3}/s. An interesting aspect is that these limits barely depend on the details of cosmic-ray propagation in the weak reacceleration case, a configuration which seems to be favored by the most recent B/C data. Though extracted from a completely different and new probe, these bounds have a strength similar to those obtained with the cosmic microwave background-they are even more stringent for p-wave annihilation.

  19. Developing Scientific Reasoning Through Drawing Cross-Sections

    NASA Astrophysics Data System (ADS)

    Hannula, K. A.

    2012-12-01

    Cross-sections and 3D models of subsurface geology are typically based on incomplete information (whether surface geologic mapping, well logs, or geophysical data). Creating and evaluating those models requires spatial and quantitative thinking skills (including penetrative thinking, understanding of horizontality, mental rotation and animation, and scaling). However, evaluating the reasonableness of a cross-section or 3D structural model also requires consideration of multiple possible geometries and geologic histories. Teaching students to create good models requires application of the scientific methods of the geosciences (such as evaluation of multiple hypotheses and combining evidence from multiple techniques). Teaching these critical thinking skills, especially combined with teaching spatial thinking skills, is challenging. My Structural Geology and Advanced Structural Geology courses have taken two different approaches to developing both the abilities to visualize and to test multiple models. In the final project in Structural Geology (a 3rd year course with a pre-requisite sophomore mapping course), students create a viable cross-section across part of the Wyoming thrust belt by hand, based on a published 1:62,500 geologic map. The cross-section must meet a number of geometric criteria (such as the template constraint), but is not required to balance. Each student tries many potential geometries while trying to find a viable solution. In most cases, the students don't visualize the implications of the geometries that they try, but have to draw them and then erase their work if it does not meet the criteria for validity. The Advanced Structural Geology course used Midland Valley's Move suite to test the cross-sections that they made in Structural Geology, mostly using the flexural slip unfolding algorithm and testing whether the resulting line lengths balanced. In both exercises, students seemed more confident in the quality of their cross-sections when the

  20. Determining the partial photoionization cross-sections of ethyl radicals.

    PubMed

    FitzPatrick, B L; Maienschein-Cline, M; Butler, L J; Lee, S-H; Lin, J J

    2007-12-13

    Using a crossed laser-molecular beam scattering apparatus, these experiments photodissociate ethyl chloride at 193 nm and detect the Cl and ethyl products, resolved by their center-of-mass recoil velocities, with vacuum ultraviolet photoionization. The data determine the relative partial cross-sections for the photoionization of ethyl radicals to form C2H5+, C2H4+, and C2H3+ at 12.1 and 13.8 eV. The data also determine the internal energy distribution of the ethyl radical prior to photoionization, so we can assess the internal energy dependence of the photoionization cross-sections. The results show that the C2H4++H and C2H3++H2 dissociative photoionization cross-sections strongly depend on the photoionization energy. Calibrating the ethyl radical partial photoionization cross-sections relative to the bandwidth-averaged photoionization cross-section of Cl atoms near 13.8 eV allows us to use these data in conjunction with literature estimates of the Cl atom photoionization cross-sections to put the present bandwidth-averaged cross-sections on an absolute scale. The resulting bandwidth-averaged cross-section for the photoionization of ethyl radicals to C2H5+ near 13.8 eV is 8+/-2 Mb. Comparison of our 12.1 eV data with high-resolution ethyl radical photoionization spectra allows us to roughly put the high-resolution spectrum on the same absolute scale. Thus, one obtains the photoionization cross-section of ethyl radicals to C2H5+ from threshold to 12.1 eV. The data show that the onset of the C2H4++H dissociative photoionization channel is above 12.1 eV; this result offers a simple way to determine whether the signal observed in photoionization experiments on complex mixtures is due to ethyl radicals. We discuss an application of the results for resolving the product branching in the O+allyl bimolecular reaction.

  1. Absolute photoionization cross-section of the methyl radical.

    PubMed

    Taatjes, Craig A; Osborn, David L; Selby, Talitha M; Meloni, Giovanni; Fan, Haiyan; Pratt, Stephen T

    2008-10-02

    The absolute photoionization cross-section of the methyl radical has been measured using two completely independent methods. The CH3 photoionization cross-section was determined relative to that of acetone and methyl vinyl ketone at photon energies of 10.2 and 11.0 eV by using a pulsed laser-photolysis/time-resolved synchrotron photoionization mass spectrometry method. The time-resolved depletion of the acetone or methyl vinyl ketone precursor and the production of methyl radicals following 193 nm photolysis are monitored simultaneously by using time-resolved synchrotron photoionization mass spectrometry. Comparison of the initial methyl signal with the decrease in precursor signal, in combination with previously measured absolute photoionization cross-sections of the precursors, yields the absolute photoionization cross-section of the methyl radical; sigma(CH3)(10.2 eV) = (5.7 +/- 0.9) x 10(-18) cm(2) and sigma(CH3)(11.0 eV) = (6.0 +/- 2.0) x 10(-18) cm(2). The photoionization cross-section for vinyl radical determined by photolysis of methyl vinyl ketone is in good agreement with previous measurements. The methyl radical photoionization cross-section was also independently measured relative to that of the iodine atom by comparison of ionization signals from CH3 and I fragments following 266 nm photolysis of methyl iodide in a molecular-beam ion-imaging apparatus. These measurements gave a cross-section of (5.4 +/- 2.0) x 10(-18) cm(2) at 10.460 eV, (5.5 +/- 2.0) x 10(-18) cm(2) at 10.466 eV, and (4.9 +/- 2.0) x 10(-18) cm(2) at 10.471 eV. The measurements allow relative photoionization efficiency spectra of methyl radical to be placed on an absolute scale and will facilitate quantitative measurements of methyl concentrations by photoionization mass spectrometry.

  2. Study of activation cross sections of deuteron induced reactions on barium. Production of 131Cs, 133Ba

    NASA Astrophysics Data System (ADS)

    Tárkányi, F.; Hermanne, A.; Ditrói, F.; Takács, S.; Szücs, Z.; Brezovcsik, K.

    2018-01-01

    In the frame of a systematic study of deuteron induced activation processes on middle mass elements, excitation functions of the natBa(d,x) 135,133,132La, 135m,133m,133mg,131mgBa, 136mg,134mg,132,129Cs reactions were measured up to 50 MeV for the first time. Cross sections were measured with the activation method using a stacked foil irradiation technique followed by HPGe γ-ray spectrometry. A comparison with the results of the nuclear model TALYS code (reported in the TENDL-2015 library) was done. The potential use of the deuteron induced reactions on Ba for applications (131Cs and 131Ba production) is discussed.

  3. Dijet cross sections in photoproduction at HERA

    NASA Astrophysics Data System (ADS)

    Derrick, M.; Krakauer, D.; Magill, S.; Mikunas, D.; Musgrave, B.; Repond, J.; Stanek, R.; Talaga, R. L.; Zhang, H.; Ayad, R.; Bari, G.; Basile, M.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Bruni, P.; Cara Romeo, G.; Castellini, G.; Chiarini, M.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; Gialas, I.; Giusti, P.; Iacobucci, G.; Laurenti, G.; Levi, G.; Margotti, A.; Massam, T.; Nania, R.; Nemoz, C.; Palmonari, F.; Polini, A.; Sartorelli, G.; Timellini, R.; Garcia, Y. Zamora; Zichichi, A.; Bargende, A.; Crittenden, J.; Desch, K.; Diekmann, B.; Doeker, T.; Eckert, M.; Feld, L.; Frey, A.; Geerts, M.; Geitz, G.; Grothe, M.; Haas, T.; Hartmann, H.; Haun, D.; Heinloth, K.; Hilger, E.; Jakob, H.-P.; Katz, U. F.; Mari, S. M.; Mass, A.; Mengel, S.; Mollen, J.; Paul, E.; Rembser, Ch.; Schattevoy, R.; Schramm, D.; Stamm, J.; Wedemeyer, R.; Campbell-Robson, S.; Cassidy, A.; Dyce, N.; Foster, B.; George, S.; Gilmore, R.; Heath, G. P.; Heath, H. F.; Llewellyn, T. J.; Morgado, C. J. S.; Norman, D. J. P.; O'Mara, J. A.; Tapper, R. J.; Wilson, S. S.; Yoshida, R.; Rau, R. R.; Arneodo, M.; Iannotti, L.; Schioppa, M.; Susinno, G.; Bernstein, A.; Caldwell, A.; Cartiglia, N.; Parsons, J. A.; Ritz, S.; Sciulli, F.; Straub, P. B.; Wai, L.; Yang, S.; Zhu, Q.; Borzemski, P.; Chwastowski, J.; Eskreys, A.; Piotrzkowski, K.; Zachara, M.; Zawiejski, L.; Adamczyk, L.; Bednarek, B.; Jelén, K.; Kisielewska, D.; Kowalski, T.; Rulikowska-Zarȩbska, E.; Suszycki, L.; Zajaç, J.; Kotański, A.; Przybycień, M.; Bauerdick, L. A. T.; Behrens, U.; Beier, H.; Bienlein, J. K.; Coldewey, C.; Deppe, O.; Desler, K.; Drews, G.; Flasiński, M.; Gilkinson, D. J.; Glasman, C.; Göttlicher, P.; Große-Knetter, J.; Gutjahr, B.; Hain, W.; Hasell, D.; Heßling, H.; Hultschig, H.; Iga, Y.; Joos, P.; Kasemann, M.; Klanner, R.; Koch, W.; Köpke, L.; Kötz, U.; Kowalski, H.; Labs, J.; Ladage, A.; Löhr, B.; Löwe, M.; Lüke, D.; Mańczak, O.; Ng, J. S. T.; Nickel, S.; Notz, D.; Ohrenberg, K.; Roco, M.; Rohde, M.; Roldán, J.; Schneekloth, U.; Schulz, W.; Selonke, F.; Stilliaris, E.; Surrow, B.; Voß, T.; Westphal, D.; Wolf, G.; Youngman, C.; Zhou, J. F.; Grabosch, H. J.; Kharchilava, A.; Leich, A.; Mattingly, M.; Meyer, A.; Schlenstedt, S.; Wulff, N.; Bagbagli, G.; Pelfer, P.; Anzivino, G.; Maccarrone, G.; De Pasquale, S.; Votano, L.; Bamberger, A.; Eisenhardt, S.; Freidhof, A.; Söldner-Rembold, S.; Schroeder, J.; Trefzger, T.; Brook, N. H.; Bussey, P. J.; Doyle, A. T.; Fleck, J. I.; Saxon, D. H.; Utley, M. L.; Wilson, A. S.; Dannemann, A.; Holm, U.; Horstmann, D.; Neumann, T.; Sinkus, R.; Wick, K.; Badura, E.; Burow, B. D.; Hagge, L.; Lohrmann, E.; Mainusch, J.; Milewski, J.; Nakahata, M.; Pavel, N.; Poelz, G.; Schott, W.; Zetsche, F.; Bacon, T. C.; Butterworth, I.; Gallo, E.; Harris, V. L.; Hung, B. Y. H.; Long, K. R.; Miller, D. B.; Morawitz, P. P. O.; Prinias, A.; Sedgbeer, J. K.; Whitfield, A. F.; Mallik, U.; McCliment, E.; Wang, M. Z.; Wang, S. M.; Wu, J. T.; Zhang, Y.; Cloth, P.; Filges, D.; An, S. H.; Hong, S. M.; Nam, S. W.; Park, S. K.; Suh, M. H.; Yon, S. H.; Imlay, R.; Kartik, S.; Kim, H.-J.; McNeil, R. R.; Metcalf, W.; Nadendla, V. K.; Barreiro, F.; Cases, G.; Graciani, R.; Hernández, J. M.; Hervás, L.; Labarga, L.; del Peso, J.; Puga, J.; Terron, J.; de Trocóniz, J. F.; Smith, G. R.; Corriveau, F.; Hanna, D. S.; Hartmann, J.; Hung, L. W.; Lim, J. N.; Matthews, C. G.; Patel, P. M.; Sinclair, L. E.; Stairs, D. G.; St. Laurent, M.; Ullmann, R.; Zacek, G.; Bashkirov, V.; Dolgoshein, B. A.; Stifutkin, A.; Bashindzhagyan, G. L.; Ermolov, P. F.; Gladilin, L. K.; Golubkov, Y. A.; Kobrin, V. D.; Kuzmin, V. A.; Proskuryakov, A. S.; Savin, A. A.; Shcheglova, L. M.; Solomin, A. N.; Zotov, N. P.; Botje, M.; Chlebana, F.; Dake, A.; Engelen, J.; de Kamps, M.; Kooijman, P.; Kruse, A.; Tiecke, H.; Verkerke, W.; Vreeswijk, M.; Wiggers, L.; de Wolf, E.; van Woudenberg, R.; Acosta, D.; Bylsma, B.; Durkin, L. S.; Honscheid, K.; Li, C.; Ling, T. Y.; McLean, K. W.; Murray, W. N.; Park, I. H.; Romanowski, T. A.; Seidlein, R.; Bailey, D. S.; Blair, G. A.; Cashmore, R. J.; Cooper-Sarkar, A. M.; Daniels, D.; Devenish, R. C. E.; Harnew, N.; Lancaster, M.; Luffman, P. E.; Lindemann, L.; McFall, J. D.; Nath, C.; Noyes, V. A.; Quadt, A.; Uijterwaal, H.; Walczak, R.; Wilson, F. F.; Yip, T.; Abbiendi, G.; Bertolin, A.; Brugnera, R.; Carlin, R.; Dal Corso, F.; De Giorgi, M.; Dosselli, U.; Limentani, S.; Morandin, M.; Porocco, M.; Stanco, L.; Stroili, R.; Voci, C.; Bulmahn, J.; Butterworth, J. M.; Feild, R. G.; Oh, B. Y.; Whitmore, J. J.; D'Agostini, G.; Marini, G.; Nigro, A.; Tassi, E.; Hart, J. C.; McCubbin, N. A.; Prytz, K.; Shah, T. P.; Short, T. L.; Barberis, E.; Dubbs, T.; Heusch, C.; Van Hook, M.; Hubbard, B.; Lockman, W.; Rahn, J. T.; Sadrozinski, H. F.-W.; Seiden, A.; Biltzinger, J.; Seifert, R. J.; Walenta, A. H.; Zech, G.; Abramowicz, H.; Briskin, G.; Dagan, S.; Levy, A.; Hasegawa, T.; Hazumi, M.; Ishii, T.; Kuze, M.; Mine, S.; Nagasawa, Y.; Nakao, M.; Suzuki, I.; Tokushuku, K.; Yamada, S.; Yamazaki, Y.; Chiba, M.; Hamatsu, R.; Hirose, T.; Homma, K.; Kitamura, S.; Nakamitsu, Y.; Yamauchi, K.; Cirio, R.; Costa, M.; Ferrero, M. I.; Lamberti, L.; Maselli, S.; Peroni, C.; Sacchi, R.; Solano, A.; Staiano, A.; Dardo, M.; Bailey, D. C.; Bandyopadhyay, D.; Benard, F.; Brkic, M.; Crombie, M. B.; Gingrich, D. M.; Hartner, G. F.; Joo, K. K.; Levman, G. M.; Martin, J. F.; Orr, R. S.; Sampson, C. R.; Teuscher, R. J.; Catterall, C. D.; Jones, T. W.; Kaziewicz, P. B.; Lane, J. B.; Saunders, R. L.; Shulman, J.; Blankenship, K.; Kochocki, J.; Lu, B.; Mo, L. W.; Bogusz, W.; Charchuła, K.; Ciborowski, J.; Gajewski, J.; Grzelak, G.; Kasprzak, M.; Krzyżanowski, M.; Muchorowski, K.; Nowak, R. J.; Pawlak, J. M.; Tymieniecka, T.; Wróblewski, A. K.; Zakrzewski, J. A.; Żarnecki, A. F.; Adamus, M.; Eisenberg, Y.; Karshon, U.; Revel, D.; Zer-Zion, D.; Ali, I.; Badgett, W. F.; Behrens, B.; Dasu, S.; Fordham, C.; Foudas, C.; Goussiou, A.; Loveless, R. J.; Reeder, D. D.; Silverstein, S.; Smith, W. H.; Vaiciulis, A.; Wodarczyk, M.; Tsurugai, T.; Bhadra, S.; Cardy, M. L.; Fagerstroem, C.-P.; Frisken, W. R.; Furutani, K. M.; Khakzad, M.; Schmidke, W. B.; ZEUS Collaboration

    1995-02-01

    Dijet production by almost real photons has been studied at HERA with the ZEUS detector. Jets have been identified using the cone algorithm. A cut on xγOBS, the fraction of the photon energy participating in the production of the two jets of highest transverse energy, is used to define cross sections sensitive to the parton distributions in the proton and in the photon. The dependence of the dijet cross sections on pseudorapidity has been measured for xγOBS ⩾ 0.75 and xγOBS < 0.75. The former is sensitive to the gluon momentum density in the proton. The latter is sensitive to the ginon in the photon. The cross sections are corrected for detector acceptance and compared to leading order QCD calculations.

  4. Cross-sectional structural parameters from densitometry

    NASA Technical Reports Server (NTRS)

    Cleek, Tammy M.; Whalen, Robert T.

    2002-01-01

    Bone densitometry has previously been used to obtain cross-sectional properties of bone from a single X-ray projection across the bone width. Using three unique projections, we have extended the method to obtain the principal area moments of inertia and orientations of the principal axes at each scan cross-section along the length of the scan. Various aluminum phantoms were used to examine scanner characteristics to develop the highest accuracy possible for in vitro non-invasive analysis of cross-sectional properties. Factors considered included X-ray photon energy, initial scan orientation, the angle spanned by the three scans (included angle), and I(min)/I(max) ratios. Principal moments of inertia were accurate to within +/-3.1% and principal angles were within +/-1 degrees of the expected value for phantoms scanned with included angles of 60 degrees and 90 degrees at the higher X-ray photon energy (140 kVp). Low standard deviations in the error (0.68-1.84%) also indicate high precision of calculated measurements with these included angles. Accuracy and precision decreased slightly when the included angle was reduced to 30 degrees. The method was then successfully applied to a pair of excised cadaveric tibiae. The accuracy and insensitivity of the algorithms to cross-sectional shape and changing isotropy (I(min)/I(max)) values when various included angles are used make this technique viable for future in vivo studies.

  5. A 23-GROUP NEUTRON THERMALIZATION CROSS SECTION LIBRARY

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Doctor, R.D.; Boling, M.A.

    1963-07-15

    A set of 23-group neutron cross sections for use in the calculation of neutron thermalization and thermal neutron spectral effects in SNAP reactors is compiled. The sources and methods used to obtain the cross sections are described. (auth)

  6. Electron induced inelastic and ionization cross section for plasma modeling

    NASA Astrophysics Data System (ADS)

    Verma, Pankaj; Mahato, Dibyendu; Kaur, Jaspreet; Antony, Bobby

    2016-09-01

    The present paper reports electron impact total inelastic and ionization cross section for silicon, germanium, and tin tetrahalides at energies varying from ionization threshold of the target to 5000 eV. These cross section data over a wide energy domain are very essential to understand the physico-chemical processes involved in various environments such as plasma modeling, semiconductor etching, atmospheric sciences, biological sciences, and radiation physics. However, the cross section data on the above mentioned molecules are scarce. In the present article, we report the computation of total inelastic cross section using spherical complex optical potential formalism and the estimation of ionization cross section through a semi-empirical method. The present ionization cross section result obtained for SiCl4 shows excellent agreement with previous measurements, while other molecules have not yet been investigated experimentally. Present results show more consistent behaviour than previous theoretical estimates. Besides cross sections, we have also studied the correlation of maximum ionization cross section with the square root of the ratio of polarizability to ionization potential for the molecules with known polarizabilities. A linear relation is observed between these quantities. This correlation is used to obtain approximate polarizability volumes for SiBr4, SiI4, GeCl4, GeBr4, and GeI4 molecules.

  7. Temperature dependence of the HNO3 UV absorption cross sections

    NASA Technical Reports Server (NTRS)

    Burkholder, James B.; Talukdar, Ranajit K.; Ravishankara, A. R.; Solomon, Susan

    1993-01-01

    The temperature dependence of the HNO3 absorption cross sections between 240 and 360 K over the wavelength range 195 to 350 nm has been measured using a diode array spectrometer. Absorption cross sections were determined using both (1) absolute pressure measurements at 298 K and (2) a dual absorption cell arrangement in which the absorption spectrum at various temperatures is measured relative to the room temperature absorption spectrum. The HNO3 absorption spectrum showed a temperature dependence which is weak at short wavelengths but stronger at longer wavelengths which are important for photolysis in the lower stratosphere. The 298 K absorption cross sections were found to be larger than the values currently recommended for atmospheric modeling (DeMore et al., 1992). Our absorption cross section data are critically compared with the previous measurements of both room temperature and temperature-dependent absorption cross sections. Temperature-dependent absorption cross sections of HNO3 are recommended for use in atmospheric modeling. These temperature dependent HNO3 absorption cross sections were used in a two-dimensional dynamical-photochemical model to demonstrate the effects of the revised absorption cross sections on loss rate of HNO3 and the abundance of NO2 in the stratosphere.

  8. Positron induced scattering cross sections for hydrocarbons relevant to plasma

    NASA Astrophysics Data System (ADS)

    Singh, Suvam; Antony, Bobby

    2018-05-01

    This article explores positron scattering cross sections by simple hydrocarbons such as ethane, ethene, ethyne, propane, and propyne. Chemical erosion processes occurring on the surface due to plasma-wall interactions are an abundant source of hydrocarbon molecules which contaminate the hydrogenic plasma. These hydrocarbons play an important role in the edge plasma region of Tokamak and ITER. In addition to this, they are also one of the major components in the planetary atmospheres and astrophysical mediums. The present work focuses on calculation of different positron impact interactions with simple hydrocarbons in terms of the total cross section (Qtot), elastic cross section (Qel), direct ionization cross section (Qion), positronium formation cross section (Qps), and total ionization cross section (Qtion). Knowing that the positron-plasma study is one of the trending fields, the calculated data have diverse plasma and astrophysical modeling applications. A comprehensive study of Qtot has been provided where the inelastic cross sections have been reported for the first time. Comparisons are made with those available from the literature, and a good agreement is obtained with the measurements.

  9. Cross-section measurements of the 94Mo(γ,n) and 90Zr(γ,n) reactions using real photons at the HIγS facility

    NASA Astrophysics Data System (ADS)

    Banu, Adriana; Silano, Jack; Karwowski, Hugon; Meekins, Evan; Bhike, Megha; Tornow, Werner; McCleskey, Mathew

    2018-05-01

    The photodisintegration reaction cross-sections for 94Mo(γ,n) and 90Zr(γ,n) have been experimentally investigated with quasi-monochromatic photon beams at the High Intensity γ-Ray Source (HIγS) facility, Triangle University Nuclear Laboratory (TUNL). The measurements were focused primarily on studying the energy dependence of the photoneutron cross sections, which is the most direct way of testing statistical models, and were performed close to the respective neutron thresholds and above up to 20 MeV. Neutrons from the (γ,n) reactions were detected using a 4π assembly of 3He proportional counters developed at Los Alamos National Laboratory and presently available at TUNL. While the 94Mo(γ,n) cross section measurement aims to contribute to a broader investigation for understanding the γ-process (the mechanism responsible for the nucleosynthesis of the so-called p-nuclei), the information from the 90Zr(γ,n) data is relevant to constrain QRPA calculations of γ-ray strength functions in this mass region. In this contribution, we will present our preliminary results of the total (γ,n) excitation functions for the two photoneutron reactions on 94Mo and 90Zr.

  10. Activation cross sections of the 64Ni(d,2n) reaction for the production of the medical radionuclide 64Cu

    NASA Astrophysics Data System (ADS)

    Hermanne, A.; Tárkányi, F.; Takács, S.; Kovalev, S. F.; Ignatyuk, A.

    2007-05-01

    Deuteron particle induced reactions for generation of 64Cu used in diagnostic and therapeutic nuclear medicine and its possible short lived contaminant 61Cu were investigated with the stacked foil activation technique on natural nickel targets up to Ed = 20.5 MeV. Excitation functions for the reactions 64Ni(d,2n) 64Cu and natNi(d, x) 61Cu are obtained by gamma spectroscopy and are compared with earlier literature values. Thick target yields have been deduced from the experimental cross sections and the predictive capability of the ALICE-IPPE, EMPIRE II and GNASH model codes is tested.

  11. Inclined Bodies of Various Cross Sections at Supersonic Speeds

    NASA Technical Reports Server (NTRS)

    Jorgensen, Leland H.

    1958-01-01

    To aid in assessing effects of cross-sectional shape on body aerodynamics, the forces and moments have been measured for bodies with circular, elliptic, square, and triangular cross sections at Mach numbers 1.98 and 3.88. Results for bodies with noncircular cross sections have been compared with results for bodies of revolution having the same axial distribution of cross-sectional area (and, thus, the same equivalent fineness ratio). Comparisons have been made for bodies of fineness ratios 6 and 10 at angles of attack from 0 deg to about 20 deg and for Reynolds numbers, based on body length, of 4.0 x 10(exp 6) and 6.7 x 10(exp 6). The results of this investigation show that distinct aerodynamic advantages can be obtained by using bodies with noncircular cross sections. At certain angles of bank, bodies with elliptic, square, and triangular cross sections develop considerably greater lift and lift-drag ratios than equivalent bodies of revolution. For bodies with elliptic cross sections, lift and pitching-moment coefficients can be correlated with corresponding coefficients for equivalent circular bodies. It has been found that the ratios of lift and pitching-moment coefficients for an elliptic body to those for an equivalent circular body are practically constant with change in both angle of attack and Mach number. These lift and moment ratios are given very accurately by slender-body theory. As a result of this agreement, the method of NACA Rep. 1048 for computing forces and moments for bodies of revolution has been simply extended to bodies with elliptic cross sections. For the cases considered (elliptic bodies of fineness ratios 6 and 10 having cross-sectional axis ratios of 1.5 and 2), agreement of theory with experiment is very good. As a supplement to the force and moment results, visual studies of the flow over bodies have been made by use of the vapor-screen, sublimation, and white-lead techniques. Photographs from these studies are included in the report.

  12. Measurement of the n-p elastic scattering angular distribution at E{sub n}=14.9 MeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Boukharouba, N.; Bateman, F. B.; Carlson, A. D.

    2010-07-15

    The relative differential cross section for the elastic scattering of neutrons by protons was measured at an incident neutron energy E{sub n}=14.9 MeV and for center-of-mass scattering angles ranging from about 60 deg. to 180 deg. Angular distribution values were obtained from the normalization of the integrated data to the n-p total elastic scattering cross section. Comparisons of the normalized data to the predictions of the Arndt et al. phase-shift analysis, those of the Nijmegen group, and with the ENDF/B-VII.0 evaluation are sensitive to the value of the total elastic scattering cross section used to normalize the data. The resultsmore » of a fit to a first-order Legendre polynomial expansion are in good agreement in the backward scattering hemisphere with the predictions of the Arndt et al. phase-shift analysis, those of the Nijmegen group, and to a lesser extent, with the ENDF/B-VII.0 evaluation. A fit to a second-order expansion is in better agreement with the ENDF/B-VII.0 evaluation than with the other predictions, in particular when the total elastic scattering cross section given by Arndt et al. and the Nijmegen group is used to normalize the data. A Legendre polynomial fit to the existing n-p scattering data in the 14 MeV energy region, excluding the present measurement, showed that a best fit is obtained for a second-order expansion. Furthermore, the Kolmogorov-Smirnov test confirms the general agreement in the backward scattering hemisphere and shows that significant differences between the database and the predictions occur in the angular range between 60 deg. and 120 deg. and below 20 deg. Although there is good overall agreement in the backward scattering hemisphere, more precision small-angle scattering data and a better definition of the total elastic cross section are needed for an accurate determination of the shape and magnitude of the angular distribution.« less

  13. Study of (n,2n) reaction on 191,193Ir isotopes and isomeric cross section ratios

    NASA Astrophysics Data System (ADS)

    Vlastou, R.; Kalamara, A.; Kokkoris, M.; Patronis, N.; Serris, M.; Georgoulakis, M.; Hassapoglou, S.; Kobothanasis, K.; Axiotis, M.; Lagoyannis, A.

    2017-09-01

    The cross section of 191Ir(n,2n)190Irg+m1 and 191Ir(n,2n)190Irm2 reactions has been measured at 17.1 and 20.9 MeV neutron energies at the 5.5 MV tandem T11/25 Accelerator Laboratory of NCSR "Demokritos", using the activation method. The neutron beams were produced by means of the 3H(d,n)4He reaction at a flux of the order of 2 × 105 n/cm2s. The neutron flux has been deduced implementing the 27Al(n,α) reaction, while the flux variation of the neutron beam was monitored by using a BF3 detector. The 193Ir(n,2n)192Ir reaction cross section has also been determined, taking into account the contribution from the contaminant 191Ir(n,γ)192Ir reaction. The correction method is based on the existing data in ENDF for the contaminant reaction, convoluted with the neutron spectra which have been extensively studied by means of simulations using the NeusDesc and MCNP codes. Statistical model calculations using the code EMPIRE 3.2.2 and taking into account pre-equilibrium emission, have been performed on the data measured in this work as well as on data reported in literature.

  14. Cross Section Sensitivity and Propagated Errors in HZE Exposures

    NASA Technical Reports Server (NTRS)

    Heinbockel, John H.; Wilson, John W.; Blatnig, Steve R.; Qualls, Garry D.; Badavi, Francis F.; Cucinotta, Francis A.

    2005-01-01

    It has long been recognized that galactic cosmic rays are of such high energy that they tend to pass through available shielding materials resulting in exposure of astronauts and equipment within space vehicles and habitats. Any protection provided by shielding materials result not so much from stopping such particles but by changing their physical character in interaction with shielding material nuclei forming, hopefully, less dangerous species. Clearly, the fidelity of the nuclear cross-sections is essential to correct specification of shield design and sensitivity to cross-section error is important in guiding experimental validation of cross-section models and database. We examine the Boltzmann transport equation which is used to calculate dose equivalent during solar minimum, with units (cSv/yr), associated with various depths of shielding materials. The dose equivalent is a weighted sum of contributions from neutrons, protons, light ions, medium ions and heavy ions. We investigate the sensitivity of dose equivalent calculations due to errors in nuclear fragmentation cross-sections. We do this error analysis for all possible projectile-fragment combinations (14,365 such combinations) to estimate the sensitivity of the shielding calculations to errors in the nuclear fragmentation cross-sections. Numerical differentiation with respect to the cross-sections will be evaluated in a broad class of materials including polyethylene, aluminum and copper. We will identify the most important cross-sections for further experimental study and evaluate their impact on propagated errors in shielding estimates.

  15. Neutron-induced fission cross section measurement of 233U, 241Am and 243Am in the energy range 0.5 MeV En 20 MeV at n TOF at CERN

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Belloni, F.; Milazzo, P. M.; Calviani, M.

    2012-01-01

    Neutron-induced fission cross section measurements of 233U, 243Am and 241Am relative to 235U have been carried out at the neutron time-of-flight facility n TOF at CERN. A fast ionization chamber has been employed. All samples were located in the same detector; therefore the studied elements and the reference 235U target are subject to the same neutron beam.

  16. Low energy e-Ar momentum transfer cross-section

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brennan, M.J.

    1992-12-01

    Recent work has shown that solutions of the Boltzmann equation which use the so called {open_quotes}two-term{close_quotes} approximation provide an inadequate description of the transverse diffusion of electrons in argon gas at low values of E/N, contrary to earlier evidence. Previous determinations of the momentum transfer cross section for argon from the analysis of transport data have used two-term codes in good faith. Progress towards the determination of a new cross section in the energy range O - 4 eV, including an analysis of the energy dependence of the uncertainty in the derived cross section is reported.

  17. Elastic scattering of ^4He by ^6Li at E(^4He) = 24, 25, and 26 MeV

    NASA Astrophysics Data System (ADS)

    Bartosz, E. E.; Cathers, P. D.; Kemper, K. W.; Maréchal, F.; Rusek, K.

    1998-11-01

    A previous optical model analysis of the elastic scattering of ^4He by ^6Li at E(^4He) = 18.5 MeV (P. V. Green, K. W. Kemper, P. L. Kerr, K. Mohajeri, E. G. Myers, D. Robson, K. Rusek and I. J. Thompson, Phys. Rev. C 53) 2862 (1996)., as well as a cluster-folded continuum- discretized coupled channels analysis (K. Rusek, P. V. Green, P. L. Kerr, and K. W. Kemper, Phys. Rev. C 56) 1895 (1997)., resulted in a good description of the data set, but the optical model analysis yielded a poor description of the 25 MeV elastic scattering data measured at the same time. New elastic and inelastic scattering angular distribution cross sections are reported for ^4He + ^6Li at E(^4He) = 24, 25 and 26 MeV. Three energies were used to rule out anomalous scattering at 25 MeV. The results of a cluster-folded continuum- discretized coupled channels analysis similar to that used with the 18.5 MeV data are presented for the three new data sets at 24, 25, and 26 MeV.

  18. Measured microwave scattering cross sections of three meteorite specimens

    NASA Technical Reports Server (NTRS)

    Hughes, W. E.

    1972-01-01

    Three meteorite specimens were used in a microwave scattering experiment to determine the scattering cross sections of stony meteorites and iron meteorites in the frequency range from 10 to 14 GHz. The results indicate that the stony meteorites have a microwave scattering cross section that is 30 to 50 percent of their projected optical cross section. Measurements of the iron meteorite scattering were inconclusive because of specimen surface irregularities.

  19. Positron total scattering cross-sections for alkali atoms

    NASA Astrophysics Data System (ADS)

    Sinha, Nidhi; Singh, Suvam; Antony, Bobby

    2018-01-01

    Positron-impact total scattering cross-sections for Li, Na, K, Rb, Cs and Fr atoms are calculated in the energy range from 5-5000 eV employing modified spherical complex optical potential formalism. The main aim of this work is to apply this formalism to the less studied positron-target collision systems. The results are compared with previous theoretical and experimental data, wherever available. In general, the present data show overall agreement and consistency with other results. Furthermore, we have done a comparative study of the results to investigate the effect of atomic size on the cross-sections as we descend through the group in the periodic table. We have also plotted a correlation graph of the present total cross-sections with polarizability and number of target electrons. The two correlation plots confirm the credibility and consistency of the present results. Besides, this is the first theoretical attempt to report positron-impact total cross-sections of alkali atoms over such a wide energy range.

  20. Cross sections of projectile-like fragments in the reaction {sup 19}F+{sup 66}Zn in the beam energy range of 3-6 MeV/nucleon

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tripathi, R.; Sudarshan, K.; Sodaye, S.

    2009-06-15

    Angular distributions of projectile-like fragments (PLFs) have been measured in the reaction {sup 19}F+{sup 66}Zn at E{sub lab}=61,82,92, and 109 MeV to understand their formation in the low energy domain (< or approx. 7 MeV nucleon). In this energy range, maximum angular momentum 'l{sub max}' in the reaction is lower than or close to the critical or limiting angular momentum for complete fusion 'l{sub lim}(CF).' The sum-rule model was modified to explain the cross sections of PLFs in the present study. For the first time, the modified sum-rule model, with a competition of incomplete fusion (ICF) reaction with complete fusionmore » below l{sub lim}(CF) reasonably reproduced the cross sections of PLFs in the beam energy range of the present study. It was observed that the cross sections of lighter PLFs fall more rapidly with decreasing beam energy compared to those of heavier PLFs, suggesting a change in the reaction mechanism from heavier to lighter PLFs. Transfer probabilities for peripheral collisions were calculated within the framework of a semiclassical formalism. The parameters of the nuclear potential required for the calculation of transfer probability were obtained by fitting the elastic scattering data measured in the present work. Calculated transfer probabilities were significantly lower compared to the corresponding experimental values, suggesting a significant overlap of the projectile and the target nuclei in incomplete fusion reactions. The present analysis showed that the overlap of the projectile and the target nuclei increases with increasing mass transfer at a given beam energy and for a given PLF, overlap increases with increasing beam energy.« less

  1. Experimental study of the p+{sup 6}Li{yields}{eta}+{sup 7}Be reaction 11.3 MeV above threshold

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Budzanowski, A.; Kliczewski, S.; Siudak, R.

    2010-10-15

    The cross section for the reaction p+{sup 6}Li{yields}{eta}+{sup 7}Be was measured at an excess energy of 11.28 MeV above threshold by detecting the recoiling {sup 7}Be nuclei. A dedicated set of focal plane detectors was built for the magnetic spectrograph Big Karl and was used for identification and four-momentum measurement of {sup 7}Be. A differential cross section of nb/(d{sigma}/d{Omega})=[0.69{+-}0.20(stat.){+-}0.20(syst.)] sr for the ground state plus 1/2{sup -} was measured. The result is compared to model calculations.

  2. Double differential light charged particle emission cross sections for some structural fusion materials

    NASA Astrophysics Data System (ADS)

    Sarpün, Ismail Hakki; n, Abdullah Aydı; Tel, Eyyup

    2017-09-01

    In fusion reactors, neutron induced radioactivity strongly depends on the irradiated material. So, a proper selection of structural materials will have been limited the radioactive inventory in a fusion reactor. First-wall and blanket components have high radioactivity concentration due to being the most flux-exposed structures. The main objective of fusion structural material research is the development and selection of materials for reactor components with good thermo-mechanical and physical properties, coupled with low-activation characteristics. Double differential light charged particle emission cross section, which is a fundamental data to determine nuclear heating and material damages in structural fusion material research, for some elements target nuclei have been calculated by the TALYS 1.8 nuclear reaction code at 14-15 MeV neutron incident energy and compared with available experimental data in EXFOR library. Direct, compound and pre-equilibrium reaction contribution have been theoretically calculated and dominant contribution have been determined for each emission of proton, deuteron and alpha particle.

  3. Statistical properties of Pu 243 , and Pu 242 ( n , γ ) cross section calculation

    DOE PAGES

    Laplace, T. A.; Zeiser, F.; Guttormsen, M.; ...

    2016-01-29

    The level density and γ-ray strength function (γSF) of 243Pu have been measured in the quasicontinuum using the Oslo method. Excited states in 243Pu were populated using the 242Pu(d,p) reaction. The level density closely follows the constant-temperature level density formula for excitation energies above the pairing gap. The γSF displays a double-humped resonance at low energy as also seen in previous investigations of actinide isotopes. The structure is interpreted as the scissors resonance and has a centroid of ω SR = 2.42(5) MeV and a total strength of B SR = 10.1(15) μ 2 N, which is in excellent agreementmore » with sum-rule estimates. Lastly, the measured level density and γSF were used to calculate the 242Pu(n,γ) cross section in a neutron energy range for which there were previously no measured data.« less

  4. Electron-pair-production cross section in the tip region of the positron spectrum

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sud, K.K.; Sharma, D.K.

    1984-11-01

    The radial integrals for electron-pair production in a point Coulomb potential have been expressed by Sud, Sharma, and Sud in terms of the matrix generalization of the GAMMA function. Two new partial differential equations in photon energy satisfied by the matrix GAMMA function are obtained. We have obtained, on integrating the partial differential equations, accurate radial integrals as a function of photon energy for the pair production by intermediate-energy photons. The cross section in the tip region of the spectrum are calculated for photons of energy 5.0 to 10.0 MeV for /sup 92/U. The new technique results in extensive savingmore » in computer time as the basic radial integrals in terms of the hypergeometric function F/sub 2/ are computed at one photon energy for each pair of partial waves. The results of our calculations are compared with plane-wave Born-approximation results and with the calculations of Dugne and of Deck, Moroi, and Alling.« less

  5. Measuring Light-ion Production and Fission Cross Sections Normalised to H(n,p) Scattering at the Upcoming NFS Facility

    NASA Astrophysics Data System (ADS)

    Jansson, K.; Gustavsson, C.; Pomp, S.; Prokofiev, A. V.; Scian, G.; Tarrío, D.

    2014-05-01

    The Medley detector setup is planned to be moved to and used at the new neutron facility NFS where measurements of light-ion production and fission cross-sections are planned at 1-40 MeV. Medley has eight detector telescopes providing ΔE-ΔE-E data, each consisting of two silicon detectors and a CsI(Tl) detector at the back. The telescope setup can be rotated and arranged to cover any angle. Medley has previously been used in many measurements at The Svedberg Laboratory (TSL) in Uppsala mainly with a quasi-mono-energetic neutron beam at 96 and 175 MeV. To be able to do measurements at NFS, which will have a white neutron beam, Medley needs to detect the reaction products with a high timing resolution providing the ToF of the primary neutron. In this paper we discuss the design of the Medley upgrade along with simulations of the setup. We explore the use of Parallel Plate Avalanche Counters (PPACs) which work very well for detecting fission fragments but require more consideration for detecting deeply penetrating particles.

  6. Survival Mediated Heavy Element Capture Cross Sections

    NASA Astrophysics Data System (ADS)

    Loveland, Walter; Yao, Larry

    2017-11-01

    Formally, the cross section for producing a heavy evaporation residue, σEVR, in a fusion reaction can be written as where E is the center of mass energy, and T is the probability of the colliding nuclei to overcome the potential barrier in the entrance channel and reach the contact point. PCN is the probability that the projectile-target system will evolve from the contact point to the compound nucleus. Wsur is the probability that the compound nucleus will decay to produce an evaporation residue rather than fissioning. However, one must remember that the Wsur term effectively sets the allowed values of the spin, which in turn, restricts the values of the capture and fusion cross sections. We point out the implications of this fact for capture cross sections for heavy element formation reactions.

  7. Measurement of the 242Pu neutron capture cross section

    NASA Astrophysics Data System (ADS)

    Buckner, M. Q.; Wu, C. Y.; Henderson, R. A.; Bucher, B.; Bredeweg, T. A.; Baramsai, B.; Couture, A.; Jandel, M.; Mosby, S.; O'Donnell, J. M.; Ullmann, J. L.; Chyzh, A.; Dance Collaboration

    2015-10-01

    Precision (n,f) and (n, γ) cross sections are important for the network calculations of the radiochemical diagnostic chain for the U.S. DOE's Stockpile Stewardship Program. 242Pu(n, γ) cross section is relevant to the network calculations of Pu and Am. Additionally, new reactor concepts have catalyzed considerable interest in the measurement of improved cross sections for neutron-induced reactions on key actinides. To date, little or no experimental data has been reported on 242Pu(n, γ) for incident neutron energy below 50 keV. A new measurement of the 242Pu(n, γ) reaction was performed with the DANCE together with an improved PPAC for fission-fragment detection at LANSCE during FY14. The relative scale of the 242Pu(n, γ) cross section spans four orders of magnitude for incident neutron energies from thermal to ~ 30 keV. The absolute scale of the 242Pu(n, γ) cross section is set according to the measured 239Pu(n,f) resonance at 7.8 eV; the target was spiked with 239Pu for this measurement. The absolute 242Pu(n, γ) neutron capture cross section is ~ 30% higher than the cross section reported in ENDF for the 2.7 eV resonance. Latest results to be reported. Funded by U.S. DOE Contract No. DE-AC52-07NA27344 (LLNL) and DE-AC52-06NA25396 (LANL). U.S. DOE/NNSA Office of Defense Nuclear Nonproliferation Research and Development. Isotopes (ORNL).

  8. Electron-Impact Total Ionization Cross Sections of Fluorine Compounds

    NASA Astrophysics Data System (ADS)

    Kim, Y.-K.; Ali, M. A.; Rudd, M. E.

    1997-10-01

    A theoretical method called the Binary-Encounter-Bethe (BEB) model(M. A. Ali, Y.-K. Kim, H. Hwang, N. M. Weinberger, and M. E. Rudd, J. Chem. Phys. 106), 9602 (1997), and references therein. that combines the Mott cross section at low incident energies T and the Bethe cross section at high T was applied to fluorine compounds of interest to plasma processing of semiconductors (CF_4, CHF_3, C_2F_6, C_4F_8, etc.). The theory provides total ioniztion cross sections in an analytic form from the threshold to a few keV in T, making it convenient to use the theory for modeling. The theory is particularly effective for closed-shell molecules. The theoretical cross sections are compared to available experimental data.

  9. Cross section for the subthreshold fission of 236U

    NASA Astrophysics Data System (ADS)

    Alekseev, A. A.; Bergman, A. A.; Berlev, A. I.; Koptelov, E. A.; Samylin, B. F.; Trufanov, A. M.; Fursov, B. I.; Shorin, V. S.

    2008-08-01

    The cross section for 236U fission in the neutron-energy range E n = 0.001 20 keV was measured by using the INR RAS (Institute of Nuclear Research, Russian Academy of Sciences, Moscow) LSDS-100 neutron spectrometer of the lead slowing-down spectrometer type. The resonance fission areas of the resonances at 5.45 eV and 1.28 keV were found, and the fission widths of these resonances were evaluated. The cross section for the 238U( n, f) fission process was measured, and the threshold sensitivity of the LSDS-100 to small values of fission cross sections was estimated. The well-known intermediate structure in the cross section for the neutron-induced subbarrier fission of 236U was confirmed.

  10. Electromagnetic Dissociation Cross Sections using Weisskopf-Ewing Theory

    NASA Technical Reports Server (NTRS)

    Adamczyk, Anne M.; Norbury, John W.

    2011-01-01

    It is important that accurate estimates of crew exposure to radiation are obtained for future long-term space missions. Presently, several space radiation transport codes exist to predict the radiation environment, all of which take as input particle interaction cross sections that describe the nuclear interactions between the particles and the shielding material. The space radiation transport code HZETRN uses the nuclear fragmentation model NUCFRG2 to calculate Electromagnetic Dissociation (EMD) cross sections. Currently, NUCFRG2 employs energy independent branching ratios to calculate these cross sections. Using Weisskopf-Ewing (WE) theory to calculate branching ratios, however, is more advantageous than the method currently employed in NUCFRG2. The WE theory can calculate not only neutron and proton emission, as in the energy independent branching ratio formalism used in NUCFRG2, but also deuteron, triton, helion, and alpha particle emission. These particles can contribute significantly to total exposure estimates. In this work, photonuclear cross sections are calculated using WE theory and the energy independent branching ratios used in NUCFRG2 and then compared to experimental data. It is found that the WE theory gives comparable, but mainly better agreement with data than the energy independent branching ratio. Furthermore, EMD cross sections for single neutron, proton, and alpha particle removal are calculated using WE theory and an energy independent branching ratio used in NUCFRG2 and compared to experimental data.

  11. Statistical Features of the Thermal Neutron Capture Cross Sections

    DOE PAGES

    Hussein, M. S.; Carlson, B. V.; Kerman, A. K.

    2016-02-01

    In this paper, we discuss the existence of huge thermal neutron capture cross sections in several nuclei. The values of the cross sections are several orders of magnitude bigger than expected at these very low energies. We lend support to the idea that this phenomenon is random in nature and is similar to what we have learned from the study of parity violation in the actinide region. The idea of statistical doorways is advanced as a unified concept in the delineation of large numbers in the nuclear world. The average number of maxima per unit mass, < n A >more » in the capture cross section is calculated and related to the underlying cross section correlation function and found to be < n A > = 3/(π√2γ A), where γ A is a characteristic mass correlation width which designates the degree of remnant coherence in the system. Finally, we trace this coherence to nucleosynthesis which produced the nuclei whose neutron capture cross sections are considered here.« less

  12. Statistical Features of the Thermal Neutron Capture Cross Sections

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hussein, M. S.; Carlson, B. V.; Kerman, A. K.

    In this paper, we discuss the existence of huge thermal neutron capture cross sections in several nuclei. The values of the cross sections are several orders of magnitude bigger than expected at these very low energies. We lend support to the idea that this phenomenon is random in nature and is similar to what we have learned from the study of parity violation in the actinide region. The idea of statistical doorways is advanced as a unified concept in the delineation of large numbers in the nuclear world. The average number of maxima per unit mass, < n A >more » in the capture cross section is calculated and related to the underlying cross section correlation function and found to be < n A > = 3/(π√2γ A), where γ A is a characteristic mass correlation width which designates the degree of remnant coherence in the system. Finally, we trace this coherence to nucleosynthesis which produced the nuclei whose neutron capture cross sections are considered here.« less

  13. Learning of Cross-Sectional Anatomy Using Clay Models

    ERIC Educational Resources Information Center

    Oh, Chang-Seok; Kim, Ji-Young; Choe, Yeon Hyeon

    2009-01-01

    We incorporated clay modeling into gross anatomy and neuro-anatomy courses to help students understand cross-sectional anatomy. By making clay models, cutting them and comparing cut surfaces to CT and MR images, students learned how cross-sectional two-dimensional images were created from three-dimensional structure of human organs. Most students…

  14. (232)Th(d,4n)(230)Pa cross-section measurements at ARRONAX facility for the production of (230)U.

    PubMed

    Duchemin, C; Guertin, A; Haddad, F; Michel, N; Métivier, V

    2014-05-01

    (226)Th (T1/2=31 min) is a promising therapeutic radionuclide since results, published in 2009, showed that it induces leukemia cells death and activates apoptosis pathways with higher efficiencies than (213)Bi. (226)Th can be obtained via the (230)U α decay. This study focuses on the (230)U production using the (232)Th(d,4n)(230)Pa(β-)(230)U reaction. Experimental cross sections for deuteron-induced reactions on (232)Th were measured from 30 down to 19 MeV using the stacked-foil technique with beams provided by the ARRONAX cyclotron. After irradiation, all foils (targets as well as monitors) were measured using a high-purity germanium detector. Our new (230)Pa cross-section values, as well as those of (232)Pa and (233)Pa contaminants created during the irradiation, were compared with previous measurements and with results given by the TALYS code. Experimentally, same trends were observed with slight differences in orders of magnitude mainly due to the nuclear data change. Improvements are ongoing about the TALYS code to better reproduce the data for deuteron-induced reactions on (232)Th. Using our cross-section data points from the (232)Th(d,4n)(230)Pa reaction, we have calculated the thick-target yield of (230)U, in Bq/μA·h. This value allows now to a full comparison between the different production routes, showing that the proton routes must be preferred. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. A design method for entrance sections of transonic wind tunnels with rectangular cross sections

    NASA Technical Reports Server (NTRS)

    Lionel, L.; Mcdevitt, J. B.

    1975-01-01

    A mathematical technique developed to design entrance sections for transonic or high-speed subsonic wind tunnels with rectangular cross sections is discribed. The transition from a circular cross-section setting chamber to a rectangular test section is accomplished smoothly so as not to introduce secondary flows (vortices or boundary-layer separation) into a uniform test stream. The results of static-pressure measurements in the transition region and of static and total-pressure surveys in the test section of a pilot model for a new facility at the Ames Research Center are presented.

  16. Observation of enhanced zero-degree binary encounter electron production with decreasing charge-state q in 30 MeV O{sup q+} + O{sub 2} collisions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zouros, T.J.M.; Wong, K.L.; Hidmi, H.I.

    We have measured binary encounter electron production in collisions of 30 MeV O{sup q+} projectiles (q=4-8) and O{sub 2} targets. Measured double differential BEe cross-sections are found to increase with decreasing charge-state q, in agreement with similar previously reported zero-degree investigations for H{sub 2} and He targets. However, measurements for the same system but at 25{degrees} shows the opposite trend, that BEe cross sections decrease slightly with decreasing charge state.

  17. Elastic scattering and total reaction cross section for the {sup 6}He+{sup 58}Ni system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Morcelle, V.; Lichtenthäler, R.; Lépine-Szily, A.

    2014-11-11

    Elastic scattering measurements of {sup 6}He + {sup 58}Ni system have been performed at the laboratory energy of 21.7 MeV. The {sup 6}He secondary beam was produced by a transfer reaction {sup 9}Be ({sup 7}Li, {sup 6}He) and impinged on {sup 58}Ni and {sup 197}Au targets, using the Radioactive Ion Beam (RIB) facility, RIBRAS, installed in the Pelletron Laboratory of the Institute of Physics of the University of São Paulo, Brazil. The elastic angular distribution was obtained in the angular range from 15° to 80° in the center of mass frame. Optical model calculations have been performed using a hybridmore » potential to fit the experimental data. The total reaction cross section was derived.« less

  18. Electron capture cross sections by O+ from atomic He

    NASA Astrophysics Data System (ADS)

    Joseph, Dwayne C.; Saha, Bidhan C.

    2009-11-01

    The adiabatic representation is used in both the quantal and semi classical molecular orbital close coupling methods (MOCC) to evaluate charge exchange cross sections. Our results show good agreement with experimental cross sections

  19. Universal Parameterization of Absorption Cross Sections

    NASA Technical Reports Server (NTRS)

    Tripathi, R. K.; Cucinotta, Francis A.; Wilson, John W.

    1997-01-01

    This paper presents a simple universal parameterization of total reaction cross sections for any system of colliding nuclei that is valid for the entire energy range from a few AMeV to a few AGeV. The universal picture presented here treats proton-nucleus collision as a special case of nucleus-nucleus collision, where the projectile has charge and mass number of one. The parameters are associated with the physics of the collision system. In general terms, Coulomb interaction modifies cross sections at lower energies, and the effects of Pauli blocking are important at higher energies. The agreement between the calculated and experimental data is better than all earlier published results.

  20. Diffractive dijet cross sections in photoproduction at HERA

    NASA Astrophysics Data System (ADS)

    Breitweg, J.; Derrick, M.; Krakauer, D.; Magill, S.; Mikunas, D.; Musgrave, B.; Repond, J.; Stanek, R.; Talaga, R. L.; Yoshida, R.; Zhang, H.; Mattingly, M. C. K.; Anselmo, F.; Antonioli, P.; Bari, G.; Basile, M.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Romeo, G. Cara; Castellini, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; Coppola, N.; Corradi, M.; de Pasquale, S.; Giusti, P.; Iacobucci, G.; Laurenti, G.; Levi, G.; Margotti, A.; Massam, T.; Nania, R.; Palmonari, F.; Pesci, A.; Polini, A.; Sartorelli, G.; Garcia, Y. Zamora; Zichichi, A.; Amelung, C.; Bornheim, A.; Brock, I.; Coböken, K.; Crittenden, J.; Deffner, R.; Eckert, M.; Grothe, M.; Hartmann, H.; Heinloth, K.; Heinz, L.; Hilger, E.; Jakob, H.-P.; Kappes, A.; Katz, U. F.; Kerger, R.; Paul, E.; Pfeiffer, M.; Stamm, J.; Wieber, H.; Bailey, D. S.; Campbell-Robson, S.; Cottingham, W. N.; Foster, B.; Hall-Wilton, R.; Heath, G. P.; Heath, H. F.; McFall, J. D.; Piccioni, D.; Roff, D. G.; Tapper, R. J.; Ayad, R.; Capua, M.; Iannotti, L.; Schioppa, M.; Susinno, G.; Kim, J. Y.; Lee, J. H.; Lim, I. T.; Pac, M. Y.; Caldwell, A.; Cartiglia, N.; Jing, Z.; Liu, W.; Mellado, B.; Parsons, J. A.; Ritz, S.; Sampson, S.; Sciulli, F.; Straub, P. B.; Zhu, Q.; Borzemski, P.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Klimek, K.; Przybycień, M. B.; Zawiejski, L.; Adamczyk, L.; Bednarek, B.; Bukowy, M.; Czermak, A. M.; Jeleń, K.; Kisielewska, D.; Kowalski, T.; Przybycień, M.; Rulikowska-Zarbska, E.; Suszycki, L.; Zajc, J.; Duliński, Z.; Kotański, A.; Abbiendi, G.; Bauerdick, L. A. T.; Behrens, U.; Beier, H.; Bienlein, J. K.; Desler, K.; Drews, G.; Fricke, U.; Gialas, I.; Goebel, F.; Göttlicher, P.; Graciani, R.; Haas, T.; Hain, W.; Hasell, D.; Hebbel, K.; Johnson, K. F.; Kasemann, M.; Koch, W.; Kötz, U.; Kowalski, H.; Lindemann, L.; Löhr, B.; Milewski, J.; Milite, M.; Monteiro, T.; Ng, J. S. T.; Notz, D.; Park, I. H.; Pellegrino, A.; Pelucchi, F.; Piotrzkowski, K.; Rohde, M.; Roldán, J.; Ryan, J. J.; Savin, A. A.; Schneekloth, U.; Schwarzer, O.; Selonke, F.; Stonjek, S.; Surrow, B.; Tassi, E.; Westphal, D.; Wolf, G.; Wollmer, U.; Youngman, C.; Zeuner, W.; Burow, B. D.; Coldewey, C.; Grabosch, H. J.; Meyer, A.; Schlenstedt, S.; Barbagli, G.; Gallo, E.; Pelfer, P.; Maccarrone, G.; Votano, L.; Bamberger, A.; Eisenhardt, S.; Markun, P.; Raach, H.; Trefzger, T.; Wölfle, S.; Bromley, J. T.; Brook, N. H.; Bussey, P. J.; Doyle, A. T.; MacDonald, N.; Saxon, D. H.; Sinclair, L. E.; Skillicorn, I. O.; Strickland, E.; Waugh, R.; Bohnet, I.; Gendner, N.; Holm, U.; Meyer-Larsen, A.; Salehi, H.; Wick, K.; Garfagnini, A.; Gladilin, L. K.; Horstmann, D.; Kçira, D.; Klanner, R.; Lohrmann, E.; Poelz, G.; Schott, W.; Zetsche, F.; Bacon, T. C.; Butterworth, I.; Cole, J. E.; Howell, G.; Lamberti, L.; Long, K. R.; Miller, D. B.; Pavel, N.; Prinias, A.; Sedgbeer, J. K.; Sideris, D.; Walker, R.; Mallik, U.; Wang, S. M.; Wu, J. T.; Cloth, P.; Filges, D.; Fleck, J. I.; Ishii, T.; Kuze, M.; Suzuki, I.; Tokushuku, K.; Yamada, S.; Yamauchi, K.; Yamazaki, Y.; Hong, S. J.; Lee, S. B.; Nam, S. W.; Park, S. K.; Barreiro, F.; Fernández, J. P.; García, G.; Glasman, C.; Hernández, J. M.; Hervás, L.; Labarga, L.; Martínez, M.; Peso, J. Del; Puga, J.; Terrón, J.; Trocóniz, J. F. De; Corriveau, F.; Hanna, D. S.; Hartmann, J.; Hung, L. W.; Murray, W. N.; Ochs, A.; Riveline, M.; Stairs, D. G.; St-Laurent, M.; Ullmann, R.; Tsurugai, T.; Bashkirov, V.; Dolgoshein, B. A.; Stifutkin, A.; Bashindzhagyan, G. L.; Ermolov, P. F.; Golubkov, Yu. A.; Khein, L. A.; Korotkova, N. A.; Korzhavina, I. A.; Kuzinin, V. A.; Lukina, O. Yu.; Proskuryakov, A. S.; Shcheglova, L. M.; Solomin, A. N.; Zotkin, S. A.; Bokel, C.; Botje, M.; Brümmer, N.; Engelen, J.; Koffeman, E.; Kooijman, P.; van Sighem, A.; Tiecke, H.; Tuning, N.; Verkerke, W.; Vossebeld, J.; Wiggers, L.; Wolf, E. De; Acosta, D.; Bylsma, B.; Durkin, L. S.; Gilmore, J.; Ginsburg, C. M.; Kim, C. L.; Ling, T. Y.; Nylander, P.; Romanowski, T. A.; Blaikley, H. E.; Cashmore, R. J.; Cooper-Sarkar, A. M.; Devenish, R. C. E.; Edmonds, J. K.; Große-Knetter, J.; Harnew, N.; Nath, C.; Noyes, V. A.; Quadt, A.; Ruske, O.; Tickner, J. R.; Walczak, R.; Waters, D. S.; Bertolin, A.; Brugnera, R.; Carlin, R.; Corso, F. Dal; Dosselli, U.; Limentani, S.; Morandin, M.; Posocco, M.; Stanco, L.; Stroili, R.; Voci, C.; Bulmahn, J.; Oh, B. Y.; Okrasiński, J. R.; Toothacker, W. S.; Whitmore, J. J.; Iga, Y.; D'Agostini, G.; Marini, G.; Nigro, A.; Raso, M.; Hart, J. C.; McCubbin, N. A.; Shah, T. P.; Epperson, D.; Heusch, C.; Rahn, J. T.; Sadrozinski, H. F.-W.; Seiden, A.; Wichmann, R.; Williams, D. C.; Abramowicz, H.; Briskin, G.; Dagan, S.; Kananov, S.; Levy, A.; Abe, T.; Fusayasu, T.; Inuzuka, M.; Nagano, K.; Umemori, K.; Yamashita, T.; Hamatsu, R.; Hirose, T.; Homma, K.; Kitamura, S.; Matsushita, T.; Arneodo, M.; Cirio, R.; Costa, M.; Ferrero, M. I.; Maselli, S.; Monaco, V.; Peroni, C.; Petrucci, M. C.; Ruspa, M.; Sacchi, R.; Solano, A.; Staiano, A.; Dardo, M.; Bailey, D. C.; Fagerstroem, C.-P.; Galea, R.; Hartner, G. F.; Joo, K. K.; Levman, G. M.; Martin, J. F.; Orr, R. S.; Polenz, S.; Sabetfakhri, A.; Simmons, D.; Teuscher, R. J.; Butterworth, J. M.; Catterall, C. D.; Hayes, M. E.; Jones, T. W.; Lane, J. B.; Saunders, R. L.; Sutton, M. R.; Wing, M.; Ciborowski, J.; Grzelak, G.; Kasprzak, M.; Nowak, R. J.; Pawlak, J. M.; Pawlak, R.; Tymieniecka, T.; Wróblewski, A. K.; Zakrzewski, J. A.; Zarnecki, A. F.; Adamus, M.; Deppe, O.; Eisenberg, Y.; Hochman, D.; Karshon, U.; Badgett, W. F.; Chapin, D.; Cross, R.; Dasu, S.; Foudas, C.; Loveless, R. J.; Mattingly, S.; Reeder, D. D.; Smith, W. H.; Vaiciulis, A.; Wodarczyk, M.; Deshpande, A.; Dhawan, S.; Hughes, V. W.; Bhadra, S.; Frisken, W. R.; Khakzad, M.; Schmidke, W. B.

    1998-08-01

    Differential dijet cross sections have been measured with the ZEUS detector for photoproduction events in which the hadronic final state containing the jets is separated with respect to the outgoing proton direction by a large rapidity gap. The cross section has been measured as a function of the fraction of the photon (ϰγ OBS) and pomeron (β OBS) momentum participating in the production of the dijet system. The observed ϰγ OBS dependence shows evidence for the presence of a resolved- as well as a direct-photon component. The measured cross section da/dβ OBS increases as β OBS increases indicating that there is a sizeable contribution to dijet production from those events in which a large fraction of the pomeron momentum participates in the hard scattering. These cross sections and the ZEUS measurements of the diffractive structure function can be described by calculations based on parton densities in the pomeron which evolve according to the QCD evolution equations and include a substantial hard momentum component of gluons in the pomeron.

  1. Reference Cross Sections for Charged-particle Monitor Reactions

    NASA Astrophysics Data System (ADS)

    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, O.; Luca, A.; Nagai, Y.; Naik, H.; Nichols, A. L.; Nortier, F. M.; Suryanarayana, S. V.; Takács, S.; Tárkányi, F. T.; Verpelli, M.

    2018-02-01

    Evaluated cross sections of beam-monitor reactions are expected to become the de-facto standard for cross-section measurements that are performed over a very broad energy range in accelerators in order to produce particular radionuclides for industrial and medical applications. The requirements for such data need to be addressed in a timely manner, and therefore an IAEA coordinated research project was launched in December 2012 to establish or improve the nuclear data required to characterise charged-particle monitor reactions. An international team was assembled to recommend more accurate cross-section data over a wide range of targets and projectiles, undertaken in conjunction with a limited number of measurements and more extensive evaluations of the decay data of specific radionuclides. Least-square evaluations of monitor-reaction cross sections including uncertainty quantification have been undertaken for charged-particle beams of protons, deuterons, 3He- and 4He-particles. Recommended beam monitor reaction data with their uncertainties are available at the IAEA-NDS medical portal http://www-nds.iaea.org/medical/monitor_reactions.html.

  2. Thresholds and the rising pion inclusive cross section

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jones, S.T.

    In the context of the hypothesis of the Pomeron-f identity, it is shown that the rising pion inclusive cross section can be explained over a wide range of energies as a series of threshold effects. Low-mass thresholds are seen to be important. In order to understand the contributions of high-mass thresholds (flavoring), a simple two-channel multiperipheral model is examined. The analysis sheds light on the relation between thresholds and Mueller-Regge couplings. In particular, it is seen that inclusive-, and total-cross-section threshold mechanisms may differ. A quantitative model based on this idea and utilizing previous total-cross-section fits is seen to agreemore » well with experiment.« less

  3. Pion Total Cross Section in Nucleon - Nucleon Collisions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    2009-01-01

    Total cross section parameterizations for neutral and charged pion production in nucleon - nucleon collisions are compared to experimental data over the projectile momentum range from threshold to 300 GeV. Both proton - proton and proton - neutron reactions are considered. Overall excellent agreement between parameterizations and experiment is found, except for notable disagreements near threshold. In addition, the hypothesis that the neutral pion production cross section can be obtained from the average charged pion cross section is checked. The theoretical formulas presented in the paper obey this hypothesis for projectile momenta below 500 GeV. The results presented provide a test of engineering tools used to calculate the pion component of space radiation.

  4. Absolute cross-section measurements of inner-shell ionization

    NASA Astrophysics Data System (ADS)

    Schneider, Hans; Tobehn, Ingo; Ebel, Frank; Hippler, Rainer

    1994-12-01

    Cross section ratios for K- and L-shell ionization of thin silver and gold targets by positron and electron impact have been determined at projectile energies of 30 70 keV. The experimental results are confirmed by calculations in plane wave Born approximation (PWBA) which include an electron exchange term and account for the deceleration or acceleration of the incident projectile in the nuclear field of the target atom. We report first absolute cross sections for K- and L-shell ionization of silver and gold targets by lepton impact in the threshold region. We have measured the corresponding cross sections for electron (e-) impact with an electron gun and the same experimental set-up.

  5. Automated Cross-Sectional Measurement Method of Intracranial Dural Venous Sinuses.

    PubMed

    Lublinsky, S; Friedman, A; Kesler, A; Zur, D; Anconina, R; Shelef, I

    2016-03-01

    MRV is an important blood vessel imaging and diagnostic tool for the evaluation of stenosis, occlusions, or aneurysms. However, an accurate image-processing tool for vessel comparison is unavailable. The purpose of this study was to develop and test an automated technique for vessel cross-sectional analysis. An algorithm for vessel cross-sectional analysis was developed that included 7 main steps: 1) image registration, 2) masking, 3) segmentation, 4) skeletonization, 5) cross-sectional planes, 6) clustering, and 7) cross-sectional analysis. Phantom models were used to validate the technique. The method was also tested on a control subject and a patient with idiopathic intracranial hypertension (4 large sinuses tested: right and left transverse sinuses, superior sagittal sinus, and straight sinus). The cross-sectional area and shape measurements were evaluated before and after lumbar puncture in patients with idiopathic intracranial hypertension. The vessel-analysis algorithm had a high degree of stability with <3% of cross-sections manually corrected. All investigated principal cranial blood sinuses had a significant cross-sectional area increase after lumbar puncture (P ≤ .05). The average triangularity of the transverse sinuses was increased, and the mean circularity of the sinuses was decreased by 6% ± 12% after lumbar puncture. Comparison of phantom and real data showed that all computed errors were <1 voxel unit, which confirmed that the method provided a very accurate solution. In this article, we present a novel automated imaging method for cross-sectional vessels analysis. The method can provide an efficient quantitative detection of abnormalities in the dural sinuses. © 2016 by American Journal of Neuroradiology.

  6. Cross sections for electron collisions with nitric oxide

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Itikawa, Yukikazu, E-mail: yukitikawa@nifty.com

    Cross section data are reviewed for electron collisions with nitric oxide. Collision processes considered are total scattering, elastic scattering, momentum transfer, excitations of rotational, vibrational, and electronic states, ionization, and dissociative electron attachment. After a survey of the literature (up to the end of 2015), recommended values of the cross section are determined, as far as possible.

  7. Scattered light and accuracy of the cross-section measurements of weak absorptions: Gas and liquid phase UV absorption cross sections of CH3CFCl2

    NASA Technical Reports Server (NTRS)

    Fahr, A.; Braun, W.; Kurylo, M. J.

    1993-01-01

    Ultraviolet absorption cross sections of CH3CFCl2(HCFC-141b) were determined in the gas phase (190-260 nm) and liquid phase (230-260 mm) at 298 K. The liquid phase absorption cross sections were then converted into accurate gas phase values using a previously described procedure. It has been demonstrated that scattered light from the shorter-wavelength region (as little as several parts per thousand) can seriously compromise the absorption cross-section measurement, particularly at longer wavelengths where cross sections are low, and can be a source of discrepancies in the cross sections of weakly absorbing halocarbons reported in the literature. A modeling procedure was developed to assess the effect of scattered light on the measured absorption cross section in our experiments, thereby permitting appropriate corrections to be made on the experimental values. Modeled and experimental results were found to be in good agreement. Experimental results from this study were compared with other available determinations and provide accurate input for calculating the atmospheric lifetime of HCFC-141b.

  8. FLOWS WITH CROSS SECTIONS

    PubMed Central

    Verjovsky, Alberto

    1970-01-01

    Let M be a compact connected C∞-manifold, of dimension n, without boundary. Let ft: M → M be a Cr-flow with cross section. Let Dr(M) be the topological group of diffeomorphisms of M with Cr-topology (1 ≤ r ≤ ∞) and let Dor(M) be its connected component of the identity. Let [unk](M) be the group of I-cobordism classes in Dr(M) generated by orientation-preserving diffeomorphisms. For fεDr(M) denote by [f] its I-cobordism class. Theorem 1 deals with the dependence of M(f) on [f]. Theorem 2: S6 × S1 has at least 28 distinct differentiable structures. Let xoεS1 and let [unk]r be the set of Cr-flows (r ≥ 1) in M × S1 with cross section M × {xo} and inducing in it the identity. Theorem 3: Intuitively to a loop in Dor based at the identity there corresponds a flow in [unk]r, and to homotopic loops correspond isotopic flows. COROLLARY. complete analysis of [unk]r/ [unk] for dim M = 2. Theorems 4 and 5 refer to Anosov flows for dim M > 3. PMID:16591849

  9. Investigation of the 66Zn(p,2pn) 64Cu and 68Zn(p,x) 64Cu nuclear processes up to 100 MeV: Production of 64Cu

    NASA Astrophysics Data System (ADS)

    Szelecsényi, F.; Steyn, G. F.; Kovács, Z.; Vermeulen, C.; van der Meulen, N. P.; Dolley, S. G.; van der Walt, T. N.; Suzuki, K.; Mukai, K.

    2005-11-01

    Cross-sections of the 66Zn(p,2pn)64Cu and 68Zn(p,x)64Cu nuclear processes were measured on highly enriched zinc targets using the stacked-foil activation technique up to 100 MeV. The new cross-sections were compared to literature data. The optimum energy range for production of 64Cu was found to be 70 → 35 MeV on 66Zn and 37 → 20 MeV on 68Zn. The thick-target yields were determined as 777 MBq/μAh (21.0 mCi/μAh) and 185 MBq/μAh (5.0 mCi/μAh), respectively. The yields of the longer-lived contaminant copper radioisotopes (i.e. 61Cu when using 66Zn as target material and both 61Cu and 67Cu in the case of 68Zn target material) were also calculated. The results obtained from the present study indicate that both reactions are suited for the production of 64Cu at a medium energy cyclotron. The optimum energy ranges are also complementary therefore the potential to utilize tandem targetry exists.

  10. Prospects for Precision Neutrino Cross Section Measurements

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Harris, Deborah A.

    2016-01-28

    The need for precision cross section measurements is more urgent now than ever before, given the central role neutrino oscillation measurements play in the field of particle physics. The definition of precision is something worth considering, however. In order to build the best model for an oscillation experiment, cross section measurements should span a broad range of energies, neutrino interaction channels, and target nuclei. Precision might better be defined not in the final uncertainty associated with any one measurement but rather with the breadth of measurements that are available to constrain models. Current experience shows that models are better constrainedmore » by 10 measurements across different processes and energies with 10% uncertainties than by one measurement of one process on one nucleus with a 1% uncertainty. This article describes the current status of and future prospects for the field of precision cross section measurements considering the metric of how many processes, energies, and nuclei have been studied.« less

  11. Fusion cross sections measurements with MUSIC

    NASA Astrophysics Data System (ADS)

    Carnelli, P. F. F.; Fernández Niello, J. O.; Almaraz-Calderon, S.; Rehm, K. E.; Albers, M.; Digiovine, B.; Esbensen, H.; Henderson, D.; Jiang, C. L.; Nusair, O.; Palchan-Hazan, T.; Pardo, R. C.; Ugalde, C.; Paul, M.; Alcorta, M.; Bertone, P. F.; Lai, J.; Marley, S. T.

    2014-09-01

    The interaction between exotic nuclei plays an important role for understanding the reaction mechanism of the fusion processes as well as for the energy production in stars. With the advent of radioactive beams new frontiers for fusion reaction studies have become accessible. We have performed the first measurements of the total fusion cross sections in the systems 10 , 14 , 15C + 12C using a newly developed active target-detector system (MUSIC). Comparison of the obtained cross sections with theoretical predictions show a good agreement in the energy region accessible with existing radioactive beams. This type of comparison allows us to calibrate the calculations for cases that cannot be studied in the laboratory with the current experimental capabilities. The high efficiency of this active detector system will allow future measurements with even more neutron-rich isotopes. The interaction between exotic nuclei plays an important role for understanding the reaction mechanism of the fusion processes as well as for the energy production in stars. With the advent of radioactive beams new frontiers for fusion reaction studies have become accessible. We have performed the first measurements of the total fusion cross sections in the systems 10 , 14 , 15C + 12C using a newly developed active target-detector system (MUSIC). Comparison of the obtained cross sections with theoretical predictions show a good agreement in the energy region accessible with existing radioactive beams. This type of comparison allows us to calibrate the calculations for cases that cannot be studied in the laboratory with the current experimental capabilities. The high efficiency of this active detector system will allow future measurements with even more neutron-rich isotopes. This work is supported by the U.S. DOE Office of Nuclear Physics under Contract No. DE-AC02-06CH11357 and the Universidad Nacional de San Martin, Argentina, Grant SJ10/39.

  12. EDDIX--a database of ionisation double differential cross sections.

    PubMed

    MacGibbon, J H; Emerson, S; Liamsuwan, T; Nikjoo, H

    2011-02-01

    The use of Monte Carlo track structure is a choice method in biophysical modelling and calculations. To precisely model 3D and 4D tracks, the cross section for the ionisation by an incoming ion, double differential in the outgoing electron energy and angle, is required. However, the double differential cross section cannot be theoretically modelled over the full range of parameters. To address this issue, a database of all available experimental data has been constructed. Currently, the database of Experimental Double Differential Ionisation Cross sections (EDDIX) contains over 1200 digitalised experimentally measured datasets from the 1960s to present date, covering all available ion species (hydrogen to uranium) and all available target species. Double differential cross sections are also presented with the aid of an eight parameter functions fitted to the cross sections. The parameters include projectile species and charge, target nuclear charge and atomic mass, projectile atomic mass and energy, electron energy and deflection angle. It is planned to freely distribute EDDIX and make it available to the radiation research community for use in the analytical and numerical modelling of track structure.

  13. Electron Impact Ionization Cross Sections in Rb and Cs.

    NASA Astrophysics Data System (ADS)

    Reddish, T. J.; Lukomski, M.; Sutton, S.; Kedzierski, W.; McConkey, J. W.; Bartschat, K.; Bartlett, P. L.; Stelbovics, A. T.; Bray, I.

    2006-05-01

    We present a new atom trapping technique for determining absolute, total ionisation cross sections (TICS) out of an excited atom. The novel feature of this method is in utilizing Doppler cooling of neutral atoms to determine ionisation cross sections. This fluorescence-monitoring experiment, which is a variant of the `trap loss' technique, has enabled us to obtain the experimental electron impact ionisation cross sections out of the Cs 6^2P3/2 excited state between 7 - 400 eV. New CCC, R-Matrix with Pseudo-States (RMPS), and Born approximation single ionisation cross sections (SICS) are also presented for both the ground and excited states of Cs and Rb, and compared with the available experimental data. The comparison of the results reveals the importance of the autoionisation and multiple ionisation contributions to the TICS. The autoionisation contribution appears to be substantial for ionisation out of the Cs 6^2P and Rb 5^2P excited states; ˜ 3-4 larger than the direct ionisation contribution predicted by CCC at ˜ 30-50 eV. This surprising result shows the importance of multi-electron processes in determining the ionisation cross sections of heavy alkali atoms.

  14. Infrared absorption cross sections of propane broadened by hydrogen

    NASA Astrophysics Data System (ADS)

    Wong, A.; Hargreaves, R. J.; Billinghurst, B.; Bernath, P. F.

    2017-09-01

    Fourier transform infrared absorption cross-sections of pure propane (C3H8) and propane broadened with H2 have been calculated from transmittance spectra recorded at temperatures from 292 K to 205 K. Transmittance spectra were recorded at the Canadian Light Source (CLS) Far-Infrared beamline, utilizing both the synchrotron source and the internal glowbar source. The absorption cross-sections have been calibrated to Pacific Northwest National Laboratory (PNNL) reference cross-sections of propane and can be used to interpret astronomical observations of giant planets such as Jupiter and Saturn as well as exoplanets.

  15. Fe L-shell Excitation Cross Section Measurements on EBIT-I

    NASA Astrophysics Data System (ADS)

    Chen, Hui; Beiersdorfer, P.; Brown, G.; Boyce, K.; Kelley, R.; Kilbourne, C.; Porter, F.; Gu, M. F.; Kahn, S.

    2006-09-01

    We report the measurement of electron impact excitation cross sections for the strong iron L-shell 3-2 lines of Fe XVII to Fe XXIV at the LLNL EBIT-I electron beam ion trap using a crystal spectrometer and NASA-Goddard Space Flight Center's 6x6 pixel array microcalorimeter. The cross sections were determined by direct normalization to the well-established cross sections for radiative electron capture. Our results include the excitation cross section for over 50 lines at multiple electron energies. Although we have found that for 3C line in Fe XVII the measured cross sections differ significantly from theory, in most cases the measurements and theory agree within 20%. This work was performed under the auspices of the U.S. DOE by LLNL under contract No. W-7405-Eng-48 and supported by NASA APRA grants to LLNL, GSFC, and Stanford University.

  16. Cross sections for the dissociative attachment of electrons to NO

    NASA Technical Reports Server (NTRS)

    Krishnakumar, E.; Srivastava, S. K.

    1988-01-01

    Cross sections for the production of O(-) by electron attachment to NO are reported. It is found that the maximum value of the cross section is about 52 percent higher than the measurement of Rapp and Briglia (1965). Cross sections for the process of polar dissociation, e + NO yields N(+) + O(_), have also been measured, and the threshold energy for this process has been obtained.

  17. Bodies with noncircular cross sections and bank-to-turn missiles

    NASA Technical Reports Server (NTRS)

    Jackson, C. M., Jr.; Sawyer, W. C.

    1986-01-01

    An evaluation is made of prospective missile applications for noncircular cross section bodies, and of recent developments in bank-to-turn missile configuration aerodynamics. The discussion encompasses cross-flow analysis techniques, as well as study results obtained for bodies with elliptical and square cross sections and with variable cross sections. Attention is given to both the performance advantages and the stability and control problems of bank-to-turn missile configurations; the aerodynamic data presented for monoplanar configurations extend to those incorporating airbreathing propulsion systems.

  18. Neutron production in deuteron-induced reactions on Li, Be, and C at an incident energy of 102 MeV

    NASA Astrophysics Data System (ADS)

    Araki, Shouhei; Watanabe, Yukinobu; Kitajima, Mizuki; Sadamatsu, Hiroki; Nakano, Keita; Kin, Tadahiro; Iwamoto, Yosuke; Satoh, Daiki; Hagiwara, Masayuki; Yashima, Hiroshi; Shima, Tatsushi

    2017-09-01

    Double-differential cross sections (DDXs) of deuteron-induced neutron production reactions on Li, Be, and C at 102 MeV were measured at forward angles (≤ 25∘) by means of a time of flight method with NE213 liquid organic scintillators at the Research Center of Nuclear Physics, Osaka University. The experimental results were compared with model calculations with PHITS and DEURACS. The DEURACS calculation reproduces the experimental DDXs for C at very forward angles than the PHITS one. Moreover, the incident energy dependence of the Li(d,xn) reaction was investigated by adding the DDX data measured previously at 25 and 40 MeV.

  19. Partial wave analysis for folded differential cross sections

    NASA Astrophysics Data System (ADS)

    Machacek, J. R.; McEachran, R. P.

    2018-03-01

    The value of modified effective range theory (MERT) and the connection between differential cross sections and phase shifts in low-energy electron scattering has long been recognized. Recent experimental techniques involving magnetically confined beams have introduced the concept of folded differential cross sections (FDCS) where the forward (θ ≤ π/2) and backward scattered (θ ≥ π/2) projectiles are unresolved, that is the value measured at the angle θ is the sum of the signal for particles scattered into the angles θ and π - θ. We have developed an alternative approach to MERT in order to analyse low-energy folded differential cross sections for positrons and electrons. This results in a simplified expression for the FDCS when it is expressed in terms of partial waves and thereby enables one to extract the first few phase shifts from a fit to an experimental FDCS at low energies. Thus, this method predicts forward and backward angle scattering (0 to π) using only experimental FDCS data and can be used to determine the total elastic cross section solely from experimental results at low-energy, which are limited in angular range.

  20. Cotton fibre cross-section properties

    USDA-ARS?s Scientific Manuscript database

    From a structural perspective the cotton fibre is a singularly discrete, elongated plant cell with no junctions or inter-cellular boundaries. Its form in nature is essentially unadulterated from the field to the spinning mill where its cross-section properties, as for any textile fibre, are central ...

  1. Infrared absorption cross sections of alternative CFCs

    NASA Technical Reports Server (NTRS)

    Clerbaux, Cathy; Colin, Reginald; Simon, Paul C.

    1994-01-01

    Absorption cross sections have obtained in the infrared atmospheric window, between 600 and 1500 cm(exp -1), for 10 alternative hydrohalocarbons: HCFC-22, HCFC-123, HCFC-124, HCFC-141b, HCFC-142b, HCFC-225ca, HCFC-225cb, HFC-125, HFC-134a, and HFC-152a. The measurements were made at three temperatures (287K, 270K and 253K) with a Fourier transform spectrometer operating at 0.03 cm(exp -1) apodized resolution. Integrated cross sections are also derived for use in radiative models to calculate the global warming potentials.

  2. Visualizing Cross-sectional Data in a Real-World Context

    NASA Astrophysics Data System (ADS)

    Van Noten, K.; Lecocq, T.

    2016-12-01

    If you could fly around your research results in three dimensions, wouldn't you like to do it? Visualizing research results properly during scientific presentations already does half the job of informing the public on the geographic framework of your research. Many scientists use the Google Earth™ mapping service (V7.1.2.2041) because it's a great interactive mapping tool for assigning geographic coordinates to individual data points, localizing a research area, and draping maps of results over Earth's surface for 3D visualization. However, visualizations of research results in vertical cross-sections are often not shown simultaneously with the maps in Google Earth. A few tutorials and programs to display cross-sectional data in Google Earth do exist, and the workflow is rather simple. By importing a cross-sectional figure into in the open software SketchUp Make [Trimble Navigation Limited, 2016], any spatial model can be exported to a vertical figure in Google Earth. In this presentation a clear workflow/tutorial is presented how to image cross-sections manually in Google Earth. No software skills, nor any programming codes are required. It is very easy to use, offers great possibilities for teaching and allows fast figure manipulation in Google Earth. The full workflow can be found in "Van Noten, K. 2016. Visualizing Cross-Sectional Data in a Real-World Context. EOS, Transactions AGU, 97, 16-19".The video tutorial can be found here: https://www.youtube.com/watch?v=Tr8LwFJ4RYU&Figure: Cross-sectional Research Examples Illustrated in Google Earth

  3. Angle-Differential Cross Sections for Radiative Recombination and the Photoelectric Effect in the K, L, and M Shells of One-Electron Systems Calculated Within AN Exact Relativistic Description

    NASA Astrophysics Data System (ADS)

    Ichihara, Akira; Eichler, Jörg

    2001-11-01

    An extensive tabulation of angle-differential cross sections for radiative recombination and, consequently, for the photoelectric effect of hydrogen-like ions with representative charge numbers Z=18, 36, 54, 66, 79, 82, and 92 is presented for the K, L, and M shells and electron energies ranging from 1.0 keV to 1.5 MeV. The cross sections, accurate to three digits, are based on fully relativistic calculations including the effects of the finite nuclear size and all multipole orders of the photon field. In order to provide a good overview, the following procedure has been adopted: For the charge numbers 18, 54, and 92, the differential cross sections are presented in figures for all subshells and for representative energies. Furthermore, as a sample of the calculations, we present a complete table for the case of Z=79. The full tabulation for all charge numbers mentioned above is provided in electronic form (http://www.idealibrary.com/links/doi/10.1006/adnd.2001.0868/dat). By simple scaling, the dependence on the projectile energy in MeV/u can be derived for accelerator experiments, and, by using elementary formulas, the differential cross section for the photoelectric effect as a function of the electron emission angle can also be obtained.

  4. New Cross Section Data for Production of the Therapeutic Radionuclides 64Cu, 140Nd, and 192Ir

    NASA Astrophysics Data System (ADS)

    Hilgers, K.; Qaim, S. M.; Coenen, H. H.

    2005-05-01

    For production of the therapeutic radionuclides 64Cu, 140Nd and 192Ir new cross section data are reported, all measured using the stacked-foil technique. In the case of 64Cu, the 66Zn(d,α)64Cu reaction was investigated radiochemically over the energy range of 5 to 14 MeV using highly enriched target material. From the measured excitation function the thick target yield of 64Cu was calculated as 6.6 MBq/μAṡh. A comparison with other production routes is given. For production of 140Nd, both natCe(3He,xn)140Nd and 141Pr(p,2n)140Nd processes were studied. For the 141Pr(p,2n)140Nd reaction the results are consistent with the literature data in the early rising part of the excitation function; at higher energies, however, our values differ considerably. The yields of 140Nd via these reactions amount to 22 and 128 MBq/μAṡh, respectively. The excitation function of the 192Os(p,n)192Ir reaction was measured from 6 to 20 MeV and the yield of 192Ir was calculated to be 0.16 MBq/μAṡh.

  5. New Cross Section Data for Production of the Therapeutic Radionuclides 64Cu, 140Nd, and 192Ir

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hilgers, K.; Qaim, S.M.; Coenen, H.H.

    2005-05-24

    For production of the therapeutic radionuclides 64Cu, 140Nd and 192Ir new cross section data are reported, all measured using the stacked-foil technique. In the case of 64Cu, the 66Zn(d,{alpha})64Cu reaction was investigated radiochemically over the energy range of 5 to 14 MeV using highly enriched target material. From the measured excitation function the thick target yield of 64Cu was calculated as 6.6 MBq/{mu}A{center_dot}h. A comparison with other production routes is given. For production of 140Nd, both natCe(3He,xn)140Nd and 141Pr(p,2n)140Nd processes were studied. For the 141Pr(p,2n)140Nd reaction the results are consistent with the literature data in the early rising part ofmore » the excitation function; at higher energies, however, our values differ considerably. The yields of 140Nd via these reactions amount to 22 and 128 MBq/{mu}A{center_dot}h, respectively. The excitation function of the 192Os(p,n)192Ir reaction was measured from 6 to 20 MeV and the yield of 192Ir was calculated to be 0.16 MBq/{mu}A{center_dot}h.« less

  6. Photoeffect cross sections of some rare-earth elements at 145.4 keV

    NASA Astrophysics Data System (ADS)

    Umesh, T. K.; Ranganathaiah, C.; Sanjeevaiah, B.

    1985-08-01

    Total attenuation cross sections in the elements La, Ce, Pr, Nd, Sm, Gd, Dy, Ho, and Er were derived from the measured total cross sections of their simple oxide compounds, by employing the mixture rule at 145.4-keV photon energy. The compound cross sections have been measured by performing transmission experiments in a good geometry setup. From the derived total cross sections of elements, photoeffect cross sections have been obtained by subtracting the theoretical scattering cross sections. A good agreement is observed between the present data of photoeffect cross sections and Scofield's theoretical data.

  7. On the Search for Nuclear Resonance Fluorescence Signatures of 235U and 238U above 3 MeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Warren, Glen A.; Caggiano, Joseph A.; Bertozzi, William

    Abstract–Nuclear resonance fluorescence is a physical process that provides an isotope-specific signature that could be used for the identification and characterization of materials. The technique involves the detection of prompt discrete-energy photons emitted from a sample that is exposed to photons in the MeV energy range. Potential applications of the technique range from detection of high explosives to characterization of special nuclear materials such as 235U. Pacific Northwest National Laboratory and Passport Systems have collaborated to conduct a a pair of measurements to search for a nuclear resonance fluorescence response of 235U above 3 MeV and of 238U above 5more » MeV using an 8 g sample of highly enriched uranium and a 90 g sample of depleted uranium. No new signatures were observed. The minimum detectable integrated cross section for 235U is presented.« less

  8. Bibliography of photoabsorption cross-section data

    NASA Technical Reports Server (NTRS)

    Hudson, R. D.; Kieffer, L. J.

    1970-01-01

    This bibliography contains only references which report a measured or calculated photoabsorption cross section (relative or normalized) in regions of continuous absorption. The bibliography is current as of January 1, 1970.

  9. Electron Impact Multiple Ionization Cross Sections for Solar Physics

    NASA Astrophysics Data System (ADS)

    Hahn, M.; Savin, D. W.; Mueller, A.

    2017-12-01

    We have compiled a set of electron-impact multiple ionization (EIMI) cross sections for astrophysically relevant ions. EIMI can have a significant effect on the ionization balance of non-equilibrium plasmas. For example, it can be important if there is a rapid change in the electron temperature, as in solar flares or in nanoflare coronal heating. EIMI is also likely to be significant when the electron energy distribution is non-thermal, such as if the electrons follow a kappa distribution. Cross sections for EIMI are needed in order to account for these processes in plasma modeling and for spectroscopic interpretation. Here, we describe our comparison of proposed semiempirical formulae to the available experimental EIMI cross section data. Based on this comparison, we have interpolated and extrapolated fitting parameters to systems that have not yet been measured. A tabulation of the fit parameters is provided for thousands of EIMI cross sections. We also highlight some outstanding issues that remain to be resolved.

  10. Total cross sections for ultracold neutrons scattered from gases

    DOE PAGES

    Seestrom, Susan Joyce; Adamek, Evan R.; Barlow, Dave; ...

    2017-01-30

    Here, we have followed up on our previous measurements of upscattering of ultracold neutrons (UCNs) from a series of gases by making measurements of total cross sections on the following gases hydrogen, ethane, methane, isobutene, n-butane, ethylene, water vapor, propane, neopentane, isopropyl alcohol, and 3He. The values of these cross sections are important for estimating the loss rate of trapped neutrons due to residual gas and are relevant to neutron lifetime measurements using UCNs. The effects of the UCN velocity and path-length distributions were accounted for in the analysis using a Monte Carlo transport code. Results are compared to ourmore » previous measurements and with the known absorption cross section for 3He scaled to our UCN energy. We find that the total cross sections for the hydrocarbon gases are reasonably described by a function linear in the number of hydrogen atoms in the molecule.« less

  11. Bodies with noncircular cross sections and bank-to-turn missiles

    NASA Technical Reports Server (NTRS)

    Jackson, C. M., Jr.; Sawyer, W. C.

    1992-01-01

    A development status evaluation is presented for the aerodynamics of missile configurations with noncircular cross-sections and bank-to-turn maneuvering systems, giving attention to cases with elliptical and square cross-sections, as well as bodies with variable cross-sections. The assessment of bank-to-turn missile performance notes inherent stability/control problems. A summary and index are provided for aerodynamic data on monoplanar configurations, including those which incorporate airbreathing propulsion systems.

  12. Projectile and Lab Frame Differential Cross Sections for Electromagnetic Dissociation

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Adamczyk, Anne; Dick, Frank

    2008-01-01

    Differential cross sections for electromagnetic dissociation in nuclear collisions are calculated for the first time. In order to be useful for three - dimensional transport codes, these cross sections have been calculated in both the projectile and lab frames. The formulas for these cross sections are such that they can be immediately used in space radiation transport codes. Only a limited amount of data exists, but the comparison between theory and experiment is good.

  13. /sub 1//sup 1/H/sup +/- and /sub 2//sup 4/He/sup +/-induced M-shell x-ray-production cross sections for selected elements in the rare-earth region

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mehta, R.; Duggan, J.L.; Price, J.L.

    1983-12-01

    The measurements of M-shell x-ray-production cross sections induced by /sub 1//sup 1/H/sup +/ and /sub 2//sup 4/He/sup +/ ions are compared to the first-Born-approximation and ECPSSR (energy loss, Coulomb-deflection effects; perturbed-stationary-state approximation, with relativistic corrections) theories. Most of the reported experimental data were measured in our laboratory and the other measurements were taken from the literature. The data from our laboratory were for incident H/sup +/ and He/sup +/ ions in the energy range from 0.25 to 2.5 MeV. The M-shell x-ray-production cross sections were measured for the following thin targets: /sub 59/Pr, /sub 60/Nd, /sub 63/Eu, /sub 64/Gd, /submore » 66/Dy, /sub 67/Ho, /sub 68/Er, /sub 70/Yb, and /sub 72/Hf. The data from the literature were for protons and He/sup +/ ions in the energy range from 30 keV to 40 MeV. These data were for the following elements: /sub 54/Xe, /sub 59/Pr, /sub 60/Nd, /sub 62/Sm, /sub 63/Eu, /sub 64/Gd, /sub 65/Tb, /sub 66/Dy, /sub 67/Ho, /sub 68/Er, /sub 70/Yb, /sub 72/Hf, /sub 73/Ta, /sub 74/W, /sub 78/Pt, /sub 79/Au, /sub 80/Hg, /sub 82/Pb, /sub 83/Bi, and /sub 92/U. The first-Born-approximation calculations of the ionization cross section were made using the plane-wave Born approximation for direct ionization and the Oppenheimer-Brinkman-Kramers approximation of Nikolaev for electron capture. The ECPSSR theory of Brandt and Lapicki (Phys. Rev. A 23, 1717 (1981)) goes beyond the first Born approximation and accounts for the energy loss, Coulomb deflection, and relativistic effects in the perturbed-stationary-state theory. The first Born approximation overpredicts all measurements. The ECPSSR theory predicts the M-shell production cross sections correctly for Z/sub 2/>70 and energies per ..mu..>0.25 MeV/..mu...« less

  14. Two-photon excitation cross-section in light and intermediate atoms

    NASA Technical Reports Server (NTRS)

    Omidvar, K.

    1980-01-01

    The method of explicit summation over the intermediate states is used along with LS coupling to derive an expression for two-photon absorption cross section in light and intermediate atoms in terms of integrals over radial wave functions. Two selection rules, one exact and one approximate, are also derived. In evaluating the radial integrals, for low-lying levels, the Hartree-Fock wave functions, and for high-lying levels, hydrogenic wave functions obtained by the quantum defect method are used. A relationship between the cross section and the oscillator strengths is derived. Cross sections due to selected transitions in nitrogen, oxygen, and chlorine are given. The expression for the cross section is useful in calculating the two-photon absorption in light and intermediate atoms.

  15. Radiative neutron capture cross sections on 176Lu at DANCE

    NASA Astrophysics Data System (ADS)

    Roig, O.; Jandel, M.; Méot, V.; Bond, E. M.; Bredeweg, T. A.; Couture, A. J.; Haight, R. C.; Keksis, A. L.; Rundberg, R. S.; Ullmann, J. L.; Vieira, D. J.

    2016-03-01

    The cross section of the neutron capture reaction 176Lu(n ,γ ) has been measured for a wide incident neutron energy range with the Detector for Advanced Neutron Capture Experiments at the Los Alamos Neutron Science Center. The thermal neutron capture cross section was determined to be (1912 ±132 ) b for one of the Lu natural isotopes, 176Lu. The resonance part was measured and compared to the Mughabghab's atlas using the R -matrix code, sammy. At higher neutron energies the measured cross sections are compared to ENDF/B-VII.1, JEFF-3.2, and BRC evaluated nuclear data. The Maxwellian averaged cross sections in a stellar plasma for thermal energies between 5 keV and 100 keV were extracted using these data.

  16. Neutron production in coincidence with fragments from the 4Ca+H reactions at Elab=357 and 565 A MeV

    NASA Astrophysics Data System (ADS)

    Tuvà, C.; Albergo, S.; Boemi, D.; Caccia, Z.; Chen, C.-X.; Costa, S.; Crawford, H. J.; Cronqvist, M.; Engelage, J.; Greiner, L.; Guzik, T. G.; Insolia, A.; Knott, C. N.; Lindstrom, P. J.; Mitchell, J. W.; Potenza, R.; Russo, G. V.; Soutoul, A.; Testard, O.; Tricomi, A.; Tull, C. E.; Waddington, C. J.; Webber, W. R.; Wefel, J. P.

    2000-04-01

    In the frame of the Transport Collaboration neutrons in coincidence with charged fragments produced in the 40Ca+H reaction at Elab=357 and 565 A MeV have been measured at the Heavy Ion Spectrometer System (HISS) facility of the Lawrence Berkeley National Laboratory, using the multifunctional neutron spectrometer MUFFINS. The detector covered a narrow angular range about the beam in the forward direction (0°-3.2°). In this contribution we report absolute neutron production cross sections in coincidence with charged fragments (10⩽Z⩽20). The neutron multiplicities have been estimated from the comparison between the neutron cross sections, in coincidence with the fragments, and the elemental cross sections. We have found evidence for a pre-equilibrium emission of prompt neutrons in superposition to a `slower' deexcitation of the equilibrated remnant by emission of nucleons and fragments, as already seen in the inclusive rapidity distributions.

  17. Cross-Sectional Transport Imaging in a Multijunction Solar Cell

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Haegel, Nancy M.; Ke, Chi-Wen; Taha, Hesham

    2015-06-14

    Combining highly localized electron-beam excitation at a point with the spatial resolution capability of optical near-field imaging, we have imaged carrier transport in a cross-sectioned multijunction (GaInP/GaInAs/Ge) solar cell. We image energy transport associated with carrier diffusion throughout the full width of the middle (GaInAs) cell and luminescent coupling from point excitation in the top cell GaInP to the middle cell. Supporting cathodoluminescence and near-field photoluminescence measurements demonstrate excitation-dependent Fermi level splitting effects that influence cross-sectioned spectroscopy results as well as transport limitations on the spatial resolution of cross-sectional measurements.

  18. Measuring the Neutron Cross Section and Detector Response from Interactions in Liquid Argon

    NASA Astrophysics Data System (ADS)

    Kamp, Nicholas; Collaboration, Captain

    2017-09-01

    The main objective of the CAPTAIN (Cryogenic Apparatus for Precision Tests of Argon Interactions with Neutrinos) program is to measure neutron and neutrino interactions in liquid argon. These results will be essential to the development of both short and long baseline neutrino experiments. The full CAPTAIN experiment involves a 10 ton liquid argon time projection chamber (LArTPC) that will take runs at a low-energy ( 10-50 MeV) stopped pion neutrino source. A two ton LArTPC, MiniCAPTAIN, will serve as a prototype for the full CAPTAIN detector. MiniCAPTAIN has been deployed to take data at the Los Alamos Neutron Science Center in late July. During this run, it will both test new LArTPC technologies and measure the cross section and detector response of neutron interactions in liquid argon. The results will be helpful in characterizing neutral current neutrino interactions and identifying background in future neutrino detection experiments. This poster gives an overview of these results and a status update on the CAPTAIN collaboration.

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

    NASA Astrophysics Data System (ADS)

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

    2017-09-01

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

  20. Energy and Mass-Number Dependence of Hadron-Nucleus Total Reaction Cross Sections

    NASA Astrophysics Data System (ADS)

    Kohama, Akihisa; Iida, Kei; Oyamatsu, Kazuhiro

    2016-09-01

    We thoroughly investigate how proton-nucleus total reaction cross sections depend on the target mass number A and the proton incident energy. In doing so, we systematically analyze nuclear reaction data that are sensitive to nuclear size, namely, proton-nucleus total reaction cross sections and differential elastic cross sections, using a phenomenological black-sphere approximation of nuclei that we are developing. In this framework, the radius of the black sphere is found to be a useful length scale that simultaneously accounts for the observed proton-nucleus total reaction cross section and first diffraction peak in the proton elastic differential cross section. This framework, which is shown here to be applicable to antiprotons, is expected to be applicable to any kind of projectile that is strongly attenuated in the nucleus. On the basis of a cross-section formula constructed within this framework, we find that a less familiar A1/6 dependence plays a crucial role in describing the energy dependence of proton-nucleus total reaction cross sections.

  1. Electromagnetic Nucleus - Nucleus Cross Sections Using Energy Dependent Branching Ratios

    NASA Astrophysics Data System (ADS)

    Adamczyk, Anne; Norbury, John

    2009-11-01

    Energy dependent branching ratios, derived from Weisskopf-Ewing theory, are presented and compared to an energy independent formalism, developed by Norbury, Townsend, and Westfall. The energy dependent branching ratio formalism is more versatile since it allows for not only neutron and proton emission, but also alpha particle, deuteron, helion, and triton emission. A new theoretical method for calculating electromagnetic dissociation (EMD) nucleus - nucleus cross sections, with energy dependent branching ratios, is introduced. Comparisons of photonuclear and nucleus - nucleus cross sections, using energy dependent and independent branching ratios, to experiment are presented. Experimental efforts, by various groups, have focused on measuring cross sections for proton and neutron emission, because proton and neutron emission is generally more probable than heavier particle emission. Consequently, comparisons of energy dependent and independent branching ratios to experiment are made for photoneutron and photoproton cross sections. EMD cross sections for single neutron, proton, and alpha particle removal are calculated and compared to experimental data for a variety of projectile, target, and energy combinations. Results indicate that using energy dependent branching ratios yields better estimates.

  2. Examination of the 22C radius determination with interaction cross sections

    NASA Astrophysics Data System (ADS)

    Nagahisa, T.; Horiuchi, W.

    2018-05-01

    A nuclear radius of 22C is investigated with the total reaction cross sections at medium- to high-incident energies in order to resolve the radius puzzle in which two recent interaction cross-section measurements using 1H and 12C targets show the quite different radii. The cross sections of 22C are calculated consistently for these target nuclei within a reliable microscopic framework, the Glauber theory. To describe appropriately such a reaction involving a spatially extended nucleus, the multiple scattering processes within the Glauber theory are fully taken into account, that is, the multidimensional integration in the Glauber amplitude is evaluated using a Monte Carlo technique without recourse to the optical-limit approximation. We discuss the sensitivity of the spatially extended halo tail to the total reaction cross sections. The root-mean-square matter radius obtained in this study is consistent with that extracted from the recent cross-section measurement on 12C target. We show that the simultaneous reproduction of the two recent measured cross sections is not feasible within this framework.

  3. Mixed Legendre moments and discrete scattering cross sections for anisotropy representation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Calloo, A.; Vidal, J. F.; Le Tellier, R.

    2012-07-01

    This paper deals with the resolution of the integro-differential form of the Boltzmann transport equation for neutron transport in nuclear reactors. In multigroup theory, deterministic codes use transfer cross sections which are expanded on Legendre polynomials. This modelling leads to negative values of the transfer cross section for certain scattering angles, and hence, the multigroup scattering source term is wrongly computed. The first part compares the convergence of 'Legendre-expanded' cross sections with respect to the order used with the method of characteristics (MOC) for Pressurised Water Reactor (PWR) type cells. Furthermore, the cross section is developed using piecewise-constant functions, whichmore » better models the multigroup transfer cross section and prevents the occurrence of any negative value for it. The second part focuses on the method of solving the transport equation with the above-mentioned piecewise-constant cross sections for lattice calculations for PWR cells. This expansion thereby constitutes a 'reference' method to compare the conventional Legendre expansion to, and to determine its pertinence when applied to reactor physics calculations. (authors)« less

  4. On the correlation of absorption cross-section with plasmonic color generation.

    PubMed

    Rezaei, Soroosh Daqiqeh; Ho, Jinfa; Ng, Ray Jia Hong; Ramakrishna, Seeram; Yang, Joel K W

    2017-10-30

    Through numerical simulations, we investigate the correlation between the absorption cross-section and the color saturation of plasmonic nanostructures of varying density. Understanding this correlation, enables the prediction of an optimal nanostructure separation, or combinations of different nanostructure sizes for plasmonic color printing applications. Here, we use metal-insulator-metal (MIM) aluminum nanostructures that support gap-plasmons. Large absorption cross-sections were observed that exceed twelve times the physical cross-section of the nanostructure disks. We derive a set of equations to determine the optimal separation for a periodic array using the absorption cross-section of an individual structure to realize saturated colors. Using the optimum pitch and enabled by the large absorption cross-sections of our structures, we employ color mixing strategies to realize a wider color gamut. The simulated color gamut exceeds the sRGB gamut for some colors, and includes dark tones. Color mixing using structures with large absorption cross-sections is a practical approach to generate a broad range of colors, in comparison to fabricating structures with continuously varying sizes.

  5. A study of the Fermi (0+) transition in {sup 14}C(p,n){sup 14}N at 495 MeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cooper, D.A.; Delucia, S.L.; Luther, B.A.

    1995-10-01

    Differential cross sections and analyzing powers have been measured for the {sup 14}C(p,n) {sup 14}N (IAS) reaction with a proton energy of 495 MeV and an angular distribution of 0{sub lab} = 0{degrees} to 10{degrees} (q = 0.0 to 0.956 fm{sup -1}) at the LAMPF Neutron Time-of-Flight Facility (NTOF). Previous A, results for targets with mixed Fermi and Gamow-Teller (AJ{close_quote} = 0+ and 1+) transitions are not well re-produced with either DWIA of RIA calculations. The {open_quotes}C target offers the best opportunity to study a Fermi transition (2.31 MeV) separated from the nearest GT strength (3.95 MeV). The results comparemore » favorably with calculations. These will be presented, and the implications for mixed transitions will be discussed.« less

  6. Measurement of the antineutrino neutral-current elastic differential cross section

    NASA Astrophysics Data System (ADS)

    Aguilar-Arevalo, A. A.; Brown, B. C.; Bugel, L.; Cheng, G.; Church, E. D.; Conrad, J. M.; Dharmapalan, R.; Djurcic, Z.; Finley, D. A.; Ford, R.; Garcia, F. G.; Garvey, G. T.; Grange, J.; Huelsnitz, W.; Ignarra, C.; Imlay, R.; Johnson, R. A.; Karagiorgi, G.; Katori, T.; Kobilarcik, T.; Louis, W. C.; Mariani, C.; Marsh, W.; Mills, G. B.; Mirabal, J.; Moore, C. D.; Mousseau, J.; Nienaber, P.; Osmanov, B.; Pavlovic, Z.; Perevalov, D.; Polly, C. C.; Ray, H.; Roe, B. P.; Russell, A. D.; Shaevitz, M. H.; Spitz, J.; Stancu, I.; Tayloe, R.; Van de Water, R. G.; Wascko, M. O.; White, D. H.; Wickremasinghe, D. A.; Zeller, G. P.; Zimmerman, E. D.; MiniBooNE Collaboration

    2015-01-01

    We report the measurement of the flux-averaged antineutrino neutral current elastic scattering cross section (d σν ¯N →ν ¯N/d Q2) on CH2 by the MiniBooNE experiment using the largest sample of antineutrino neutral current elastic candidate events ever collected. The ratio of the antineutrino to neutrino neutral current elastic scattering cross sections and a ratio of the antineutrino neutral current elastic to antineutrino charged current quasielastic cross sections are also presented.

  7. Measurement of the antineutrino neutral-current elastic differential cross section

    DOE PAGES

    Aguilar-Arevalo, A.  A.; Brown, B.  C.; Bugel, L.; ...

    2015-01-08

    We report the measurement of the flux-averaged antineutrino neutral current elastic scattering cross section (dσ ν-barN→ν-barN/dQ 2) on CH 2 by the MiniBooNE experiment using the largest sample of antineutrino neutral current elastic candidate events ever collected. The ratio of the antineutrino to neutrino neutral current elastic scattering cross sections and a ratio of the antineutrino neutral current elastic to antineutrino charged current quasi elastic cross sections are also presented.

  8. Measurement of numu induced charged current inclusive cross section on water using the near detector of the T2K experiment

    NASA Astrophysics Data System (ADS)

    Das, Rajarshi

    The Tokai to Kamioka (T2K) Experiment is a long-baseline neutrino oscillation experiment located in Japan with the primary goal to measure precisely multiple neutrino flavor oscillation parameters. An off-axis muon neutrino beam peaking at 600 MeV is generated at the JPARC facility and directed towards the 50 kiloton Super-Kamiokande (SK) water Cherenkov detector located 295 km away. Measurements from a Near Detector that is 280m downstream of the neutrino beam target are used to constrain uncertainties in the beam flux prediction and neutrino interaction rates. We present a selection of inclusive charged current neutrino interactions on water. We used several sub-detectors in the ND280 complex, including a Pi-Zero detector (P0D) that has alternating planes of plastic scintillator and water bag layers, a time projection chamber (TPC) and fine-grained detector (FGD) to detect and reconstruct muons from neutrino charged current events. We use a statistical subtraction method with the water-in and water-out inclusive selection to extract a flux-averaged, ν_μ induced, charged current inclusive cross section. We also outline the evaluation of systematic uncertainties. We find an absolute cross section of ⟨σ⟩=(6.37 ± 0.157(stat.) (-1.060/+0.910(sys.)) x 10-39 (cm. 2/H2O nucleon). This is the first ν_μ charged current inclusive cross section measurement on water.

  9. Neutrino-nucleon cross sections at energies of Megaton-scale detectors

    NASA Astrophysics Data System (ADS)

    Gazizov, A.; Kowalski, M.; Kuzmin, K. S.; Naumov, V. A.; Spiering, Ch.

    2016-04-01

    An updated set of (anti)neutrino-nucleon charged and neutral current cross sections at 3 GeV ≲ Eν ≲100 GeV is presented. These cross sections are of particular interest for the detector optimization and data processing and interpretation in the future Megaton-scale experiments like PINGU, ORCA, and Hyper-Kamiokande. Finite masses of charged leptons and target mass corrections in exclusive and deep inelastic (ν̅)νN interactions are taken into account. A new set of QCD NNLO parton density functions, ABMP15, is used for calculation of the DIS cross sections. The sensitivity of the cross sections to phenomenological parameters and to extrapolations of the nucleon structure functions to small x and Q2 is studied. An agreement within the uncertainties of our calculations with experimental data is demonstrated.

  10. NASA-Lewis experiences with multigroup cross sections and shielding calculations

    NASA Technical Reports Server (NTRS)

    Lahti, G. P.

    1972-01-01

    The nuclear reactor shield analysis procedures employed at NASA-Lewis are described. Emphasis is placed on the generation, use, and testing of multigroup cross section data. Although coupled neutron and gamma ray cross section sets are useful in two dimensional Sn transport calculations, much insight has been gained from examination of uncoupled calculations. These have led to experimental and analytic studies of areas deemed to be of first order importance to reactor shield calculations. A discussion is given of problems encountered in using multigroup cross sections in the resolved resonance energy range. The addition to ENDF files of calculated and/or measured neutron-energy-dependent capture gamma ray spectra for shielding calculations is questioned for the resonance region. Anomalies inherent in two dimensional Sn transport calculations which may overwhelm any cross section discrepancies are illustrated.

  11. Validity of Hansen-Roach cross sections in low-enriched uranium systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Busch, R.D.; O'Dell, R.D.

    Within the nuclear criticality safety community, the Hansen-Roach 16 group cross section set has been the standard'' for use in k{sub eff} calculations over the past 30 years. Yet even with its widespread acceptance, there are still questions about its validity and adequacy, about the proper procedure for calculating the potential scattering cross section, {sigma}{sub p}, for uranium and plutonium, and about the concept of resonance self shielding and its impact on cross sections. This paper attempts to address these questions. It provides a brief background on the Hansen-Roach cross sections. Next is presented a review of resonances in crossmore » sections, self shielding of these resonances, and the use of {sigma}{sub p} to characterize resonance self shielding. Three prescriptions for calculating {sigma}{sub p} are given. Finally, results of several calculations of k{sub eff} on low-enriched uranium systems are provided to confirm the validity of the Hansen-Roach cross sections when applied to such systems.« less

  12. A New Measurement of Neutron Induced Fission Cross Sections

    NASA Astrophysics Data System (ADS)

    Magee, Joshua; Niffte Collaboration

    2017-09-01

    Neutron induced fission cross sections of actinides are of great interest in nuclear energy and stockpile stewardship. Traditionally, measurements of these cross sections have been made with fission chambers, which provide limited information on the actual fragments, and ultimately result in uncertainties on the order of several percent. The Neutron Induced Fission ragment Tracking Experiment (NIFFTE) collaboration designed and built a fission Time Projection Chamber (fissionTPC), which provides additional information on these processes, through 3-dimensional tracking, improved particle identification, and in-situ profiles of target and beam non-uniformities. Ultimately, this should provide sub-percent measurements of (n,f) cross-sections. During the 2016 run cycle, measurements of the 238U(n,f)/235U(n,f) cross section shape was performed at the Los Alamos Neutron Science Center (LANSCE) Weapons Neutron Research (WNR) facility. An overview of the fission TPC will be given, as well as these recently reported results. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  13. Radiative neutron capture cross section from 236U

    NASA Astrophysics Data System (ADS)

    Baramsai, B.; Jandel, M.; Bredeweg, T. A.; Bond, E. M.; Roman, A. R.; Rusev, G.; Walker, C. L.; Couture, A.; Mosby, S.; O'Donnell, J. M.; Ullmann, J. L.; Kawano, T.

    2017-08-01

    The 236U(n ,γ ) reaction cross section has been measured for the incident neutron energy range from 10 eV to 800 keV by using the Detector for Advanced Neutron Capture Experiments (DANCE) γ -ray calorimeter at the Los Alamos Neutron Science Center. The cross section was determined with the ratio method, which is a technique that uses the 235U(n ,f ) reaction as a reference. The results of the experiment are reported in the resolved and unresolved resonance energy regions. Individual neutron resonance parameters were obtained below 1 keV incident energy by using the R -matrix code sammy. The cross section in the unresolved resonance region is determined with improved experimental uncertainty. It agrees with both ENDF/B-VII.1 and JEFF-3.2 nuclear data libraries. The results above 10 keV agree better with the JEFF-3.2 library.

  14. Evaluation of nuclear reaction cross section data for the production of (87)Y and (88)Y via proton, deuteron and alpha-particle induced transmutations.

    PubMed

    Zaneb, H; Hussain, M; Amjad, N; Qaim, S M

    2016-06-01

    Proton, deuteron and alpha-particle induced reactions on (87,88)Sr, (nat)Zr and (85)Rb targets were evaluated for the production of (87,88)Y. The literature data were compared with nuclear model calculations using the codes ALICE-IPPE, TALYS 1.6 and EMPIRE 3.2. The evaluated cross sections were generated; therefrom thick target yields of (87,88)Y were calculated. Analysis of radio-yttrium impurities and yield showed that the (87)Sr(p, n)(87)Y and (88)Sr(p, n)(88)Y reactions are the best routes for the production of (87)Y and (88)Y respectively. The calculated yield for the (87)Sr(p, n)(87)Y reaction is 104 MBq/μAh in the energy range of 14→2.7MeV. Similarly, the calculated yield for the (88)Sr(p, n)(88)Y reaction is 3.2 MBq/μAh in the energy range of 15→7MeV. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Intermediate Nuclear Structure for 2v 2{beta} Decay of {sup 48}Ca Studied by (p, n) and (n, p) Reactions at 300 MeV

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sakai, H.; Yako, K.

    2009-08-26

    Angular distributions of the double differential cross sections for the {sup 48}Ca(p,n) and the {sup 48}Ti(n,p) reactions were measured at 300 MeV. A multipole decomposition technique was applied to the spectra to extract the Gamow-Teller (GT) transition strengths. In the (n, p) spectrum beyond 8 MeV excitation energy extra B(GT{sup +}) strengths which are not predicted by the shell model calculation. This extra B(GT{sup +}) strengths significantly contribute to the nuclear matrix element of the 2v2{beta}-decay.

  16. Proton-Nucleus Elastic Cross Sections Using Two-Body In-Medium Scattering Amplitudes

    NASA Technical Reports Server (NTRS)

    Tripathi, R. K.; Wilson, John W.; Cucinotta, Francis A.

    2001-01-01

    Recently, a method was developed of extracting nucleon-nucleon (NN) cross sections in the medium directly from experiment. The in-medium NN cross sections form the basic ingredients of several heavy-ion scattering approaches including the coupled-channel approach developed at the Langley Research Center. The ratio of the real to the imaginary part of the two-body scattering amplitude in the medium was investigated. These ratios are used in combination with the in-medium NN cross sections to calculate elastic proton-nucleus cross sections. The agreement is excellent with the available experimental data. These cross sections are needed for the radiation risk assessment of space missions.

  17. Corporate Social Responsibility: A Cross Sectional Examination of Incentivization.

    DTIC Science & Technology

    1995-09-01

    which address organizational behavior: Corporate Social Responsibility ( CSR ), Expense Preference Approach (EPA), Resource Dependency Theory (RDT...i V *>V CORPORATE SOCIAL RESPONSIBILITY : A CROSS SECTIONAL EXAMINATION OF INCENTIVIZATION THESIS Jennifer A. Block, B.S. First Lieutenant, USAF...Distribution/ Availability Codes Dist m Avail and/or Special \\&\\W 0\\1 CORPORATE SOCIAL RESPONSIBILITY : A CROSS SECTIONAL EXAMINATION OF

  18. Multigroup cross section library for GFR2400

    NASA Astrophysics Data System (ADS)

    Čerba, Štefan; Vrban, Branislav; Lüley, Jakub; Haščík, Ján; Nečas, Vladimír

    2017-09-01

    In this paper the development and optimization of the SBJ_E71 multigroup cross section library for GFR2400 applications is discussed. A cross section processing scheme, merging Monte Carlo and deterministic codes, was developed. Several fine and coarse group structures and two weighting flux options were analysed through 18 benchmark experiments selected from the handbook of ICSBEP and based on performed similarity assessments. The performance of the collapsed version of the SBJ_E71 library was compared with MCNP5 CE ENDF/B VII.1 and the Korean KAFAX-E70 library. The comparison was made based on integral parameters of calculations performed on full core homogenous models.

  19. Electron impact ionisation cross sections of iron oxides

    NASA Astrophysics Data System (ADS)

    Huber, Stefan E.; Mauracher, Andreas; Sukuba, Ivan; Urban, Jan; Maihom, Thana; Probst, Michael

    2017-12-01

    We report electron impact ionisation cross sections (EICSs) of iron oxide molecules, FexOx and FexOx+1 with x = 1, 2, 3, from the ionisation threshold to 10 keV, obtained with the Deutsch-Märk (DM) and binary-encounter-Bethe (BEB) methods. The maxima of the EICSs range from 3.10 to 9 . 96 × 10-16 cm2 located at 59-72 eV and 5.06 to 14.32 × 10-16 cm2 located at 85-108 eV for the DM and BEB approaches, respectively. The orbital and kinetic energies required for the BEB method are obtained by employing effective core potentials for the inner core electrons in the quantum chemical calculations. The BEB cross sections are 1.4-1.7 times larger than the DM cross sections which can be related to the decreasing population of the Fe 4s orbitals upon addition of oxygen atoms, together with the different methodological foundations of the two methods. Both the DM and BEB cross sections can be fitted excellently to a simple analytical expression used in modelling and simulation codes employed in the framework of nuclear fusion research. Supplementary material in the form of one pdf file available from the Journal web page at http://https://doi.org/10.1140/epjd/e2017-80308-2.

  20. Consistency between cross-sectional and longitudinal SNP: blood lipid associations.

    PubMed

    Costanza, Michael C; Beer-Borst, Sigrid; James, Richard W; Gaspoz, Jean-Michel; Morabia, Alfredo

    2012-02-01

    Various studies have linked different genetic single nucleotide polymorphisms (SNPs) to different blood lipids (BL), but whether these "connections" were identified using cross-sectional or longitudinal (i.e., changes over time) designs has received little attention. Cross-sectional and longitudinal assessments of BL [total, high-, low-density lipoprotein cholesterol (TC, HDL, LDL), triglycerides (TG)] and non-genetic factors (body mass index, smoking, alcohol intake) were measured for 2,002 Geneva, Switzerland, adults during 1999-2008 (two measurements, median 6 years apart), and 20 SNPs in 13 BL metabolism-related genes. Fixed and mixed effects repeated measures linear regression models, respectively, were employed to identify cross-sectional and longitudinal SNP:BL associations among the 1,516 (76%) study participants who reported not being treated for hypercholesterolemia at either measurement time. One-third more (12 vs. 9) longitudinal than cross-sectional associations were found [Bonferroni-adjusted two-tailed p < 0.00125 (=0.05/2)/20) for each of the four ensembles of 20 SNP:individual BL associations tested under the two study designs]. There was moderate consistency between the cross-sectional and longitudinal findings, with eight SNP:BL associations consistently identified across both study designs: [APOE.2 and APOE.4 (rs7412 and rs429358)]:TC; HL/LIPC (rs2070895):HDL; [APOB (rs1367117), APOE.2 and APOE.4 (rs7412 and rs429358)]:LDL; [APOA5 (rs2072560) and APOC III (rs5128)]:TG. The results suggest that cross-sectional studies, which include most genome-wide association studies (GWAS), can assess the large majority of SNP:BL associations. In the present analysis, which was much less powered than a GWAS, the cross-sectional study was around 2/3 (67%) as efficient as the longitudinal study.