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Re in the keV energy regionKatabuchi, Tatsuya*; Sato, Yaoki*; Takebe, Karin*; Igashira, Masayuki*; Umezawa, Seigo*; Fujioka, Ryo*; Saito, Tatsuhiro*; Iwamoto, Nobuyuki
Journal of Nuclear Science and Technology, 6 Pages, 2024/00
Times Cited Count：0 Percentile：0.08(Nuclear Science & Technology)Nakamura, Shoji; Endo, Shunsuke; Kimura, Atsushi; Shibahara, Yuji*
KURNS Progress Report 2022, P. 73, 2023/07
The present study is concerned with the neutron capture cross-sections that contribute to the evaluation of the amount of radionuclides possessing problems in decommissioning. In this study, 
Sc, 
Cu, 
Zn, 
Ag, 
In and 
W were selected among the objective nuclides, and their thermal-neutron capture cross-sections were measured using TC-Pn equipment of the KUR of the Institute for Integrated Radiation and Nuclear Science, Kyoto University. High purity metal samples were prepared. A gold-aluminum ally wire, cobalt and molybdenum foils were used to monitor the neutron flux at the irradiation position of TC-Pn. The flux monitors and metal samples were irradiated for 1 hour at 1-MW operation of the KUR. After irradiation, the irradiation capsule was opened, samples and flux monitors were enclosed in a vinyl bag one by one, and then 
rays emitted from the samples and monitors were measured with a high-purity Ge detector. The thermal-neutron flux component was derived with the reaction rates of flux monitors (
Au, 
Co and 
Mo) on the basis of Westcott's convention, and found to be (5.92
0.10)
10
n/cm
/sec at the irradiation position. The measured reaction rate for each metal sample divided by the evaluated thermal-neutron capture cross-section should give the same value of the thermal-neutron flux component if the cross section is suitable. This time, we found that the cross sections of Sc and 
Zn were consistent with the evaluated one, but those of other nuclides were inconsistent with their evaluated ones; that is, it turned out that their thermal-neutron capture cross-sections should be modified.
methodNauchi, Yasushi*; Sato, Shunsuke*; Hayakawa, Takehito*; Kimura, Yasuhiko; Suyama, Kenya; Kashima, Takao*; Futakami, Kazuhiro*
Nuclear Instruments and Methods in Physics Research A, 1050, p.168109_1 - 168109_9, 2023/05
Times Cited Count：0 Percentile：0.02(Instruments & Instrumentation)Measurement of neutrons from spent nuclear fuel is performed in this study using the H method, which detects 2.223 MeV rays from neutron capture reaction of hydrogen using a highly pure germanium (HPGe) detector. The detection of the 2.223 MeV ray is affected by intense ray emission from fission products (FPs) because the emission rate of rays from the FP is seven orders of magnitude higher than the emission rate of neutrons. To shield the intense ray from the FP, the HPGe detector is placed off the axis of a collimator, whereas a polyethylene block is placed on the axis. In this geometry, the detector is shielded from the intense rays from the FP, but the detector can measure 2.223 MeV rays from the H reactions in the polyethylene block. The measured count rate of the 2.223 MeV rays is consistent with the expected rate within the statistical error, which is calculated based on the nuclide composition, which is primary 
Cm, estimated via depletion and decay calculations. Accordingly, the H method is considered feasible to quantify the number of neutron leakage from spent nuclear fuel assembly, which is applicable to certify burn up of the assembly.
Segawa, Mariko; Toh, Yosuke; Kai, Tetsuya; Kimura, Atsushi; Nakamura, Shoji
Annals of Nuclear Energy, 167, p.108828_1 - 108828_5, 2022/03
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)Nakamura, Shoji; Hatsukawa, Yuichi*; Kimura, Atsushi; Toh, Yosuke; Harada, Hideo
Journal of Nuclear Science and Technology, 58(12), p.1318 - 1329, 2021/12
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)The present study performed fast-neutron capture cross-section measurement of 
Tc by an activation method using a fast-neutron source reactor "YAYOI" of the University of Tokyo. Technetium-99 samples were irradiated with reactor neutrons using a pneumatic system. Reaction rates of Tc were obtained by measuring decay gamma rays emitted from 
Tc. The neutron flux at an irradiation position was monitored with gold foils. The fast-neutron capture cross section of Tc at neutron energy of 85 keV was derived as 0.4320.023 barn by using the reaction rates of Tc, evaluated cross-section data and the fast-neutron flux spectrum of the YAYOI reactor. The present study agreed with the evaluated nuclear data library JENDL-4.0.
-process nucleosynthesisBhattacharyya, A.*; Datta, U.*; Rahaman, A.*; Chakraborty, S.*; Aumann, T.*; Beceiro-Novo, S.*; Boretzky, K.*; Caesar, C.*; Carlson, B. V.*; Catford, W. N.*; et al.
Physical Review C, 104(4), p.045801_1 - 045801_14, 2021/10
Times Cited Count：5 Percentile：63.69(Physics, Nuclear)no abstracts in English
Np using graphite thermal columnNakamura, Shoji; Endo, Shunsuke; Kimura, Atsushi; Shibahara, Yuji*
KURNS Progress Report 2020, P. 94, 2021/08
The present study selected Np among radioactive nuclides and aimed to converge a contradiction between reported thermal-neutron capture cross sections. Neutron irradiation was carried out using the graphite thermal column equipped with the Kyoto University Research Reactor. A solution equivalent to 950 Bq order of radioactivity was pipetted out of a Np standard solution and dropped onto a fiber filter, which was then dried with an infrared lamp to prepare a Np sample. The Np sample was quantified using 312-keV gamma ray emitted from 
Pa in a radiation equilibrium with Np. To monitor a thermal-neutron flux component at an irradiation position, the Np sample was irradiated together with several stable nuclides as neutron flux monitors: Sc, Co, Mo, 
Ta and Au. The reaction rate of Np was obtained from gamma-ray yields given by 
Np and Pa, and then the thermal-neutron capture cross section of Np was derived.
YKatabuchi, Tatsuya*; Toh, Yosuke; Mizumoto, Motoharu*; Saito, Tatsuhiro*; Terada, Kazushi*; Kimura, Atsushi; Nakamura, Shoji; Huang, M.*; Rovira Leveroni, G.; Igashira, Masayuki*
European Physical Journal A, 57(1), p.4_1 - 4_4, 2021/01
Times Cited Count：3 Percentile：45.55(Physics, Nuclear)Katabuchi, Tatsuya*; Iwamoto, Osamu; Hori, Junichi*; Kimura, Atsushi; Iwamoto, Nobuyuki; Nakamura, Shoji; Shibahara, Yuji*; Terada, Kazushi*; Rovira, G.*; Matsuura, Shota*
EPJ Web of Conferences, 239, p.01044_1 - 01044_4, 2020/09
Times Cited Count：2 Percentile：86.62(Nuclear Science & Technology)P
rez S
nchez, R.*; Jurado, B.*; Mot, V.*; Roig, O.*; Dupuis, M.*; Bouland, O.*; Denis-Petit, D.*; Marini, P.*; Mathieu, L.*; Tsekhanovich, I.*; et al.
Physical Review Letters, 125(12), p.122502_1 - 122502_5, 2020/09
Times Cited Count：14 Percentile：71.69(Physics, Multidisciplinary)Katabuchi, Tatsuya*; Iwamoto, Osamu; Hori, Junichi*; Iwamoto, Nobuyuki; Kimura, Atsushi; Nakamura, Shoji; Shibahara, Yuji*; Terada, Kazushi*
JAEA-Conf 2019-001, p.193 - 197, 2019/11
Nakamura, Shoji; Terada, Kazushi*; Kimura, Atsushi; Nakao, Taro*; Iwamoto, Osamu; Harada, Hideo; Uehara, Akihiro*; Takamiya, Koichi*; Fujii, Toshiyuki*
Journal of Nuclear Science and Technology, 56(1), p.123 - 129, 2019/01
Times Cited Count：1 Percentile：10.81(Nuclear Science & Technology)Accurate data of -ray emission probabilities are frequently needed when one quantitatively determines the amount of isotope by -ray measurements or obtains neutron capture cross-sections using them. Americium-243, one of the most important minor actinides, produces Am after neutron capture. The 744-keV -ray decaying from the ground state of Am has a relatively large -ray emission probability c.a. 66%, however, its uncertainty is as large as 29%. The uncertainty of the -ray emission probability leads to a major factor of the systematic uncertainty on determining an amount of isotope, and therefore the -ray emission probability was measured by using an activation method and an examined level structure of Cm. In this study, the emission probability of 744-keV ray was derived as 66.51.1%, and its uncertainty was improved from 29% to 2%.
Nakao, Taro; Terada, Kazushi; Kimura, Atsushi; Nakamura, Shoji; Iwamoto, Osamu; Harada, Hideo; Katabuchi, Tatsuya*; Igashira, Masayuki*; Hori, Junichi*
EPJ Web of Conferences, 146, p.03021_1 - 03021_4, 2017/09
Times Cited Count：7 Percentile：96.18(Nuclear Science & Technology)A new data acquisition system (DAQ system) in J-PARC Materials and Life Science Experimental Facility (MLF) ANNRI was developed. Increasing beam power of MLF in recent years allows beam line users to obtain high quantity experimental data yields. Compared to 2008, more than 20 times beam current is achieved in 2015. For the purpose to correspond strong beam power of MLF, a new DAQ system for the array of the Ge detectors in ANNRI is developed. The DAQ system is also going to be used for processing signals from a Li glass detector, which is under development at ANNRI for measurement of total neutron cross sections. Commissioning experiment of a new DAQ system at ANNRI was performed by using 0.1mmt Au sample with 500kW J-PARC proton beam power. An applicability of time-of-flight method for both neutron capture and total cross-sections measurements was checked. ADC and TDC nonlinearity, energy resolution, multi-channel coincidence and dead time performance for the array of the Ge detectors were also evaluated. The dead time value for Ge detectors was successfully decreased to 1/4 from the previous DAQ system with minor deterioration on energy resolution. The author would like to thank the accelerator and technical staff at J-PARC for operation of the accelerator and the neutron production target and for the other experimental supports. Present study includes the result of "Research and Development for accuracy improvement of neutron nuclear data on minor actinides" entrusted to the Japan Atomic Energy Agency by the Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT).
Am at neutron energies below fission thresholdHirose, Kentaro; Nishio, Katsuhisa; Makii, Hiroyuki; Nishinaka, Ichiro*; Ota, Shuya*; Nagayama, Tatsuro*; Tamura, Nobuyuki*; Goto, Shinichi*; Andreyev, A. N.; Vermeulen, M. J.; et al.
Nuclear Instruments and Methods in Physics Research A, 856, p.133 - 138, 2017/06
Times Cited Count：5 Percentile：44.07(Instruments & Instrumentation)
Cs(n,) cross-section using a New DAQ System at ANNRIHales, B. P.; Nakamura, Shoji; Kimura, Atsushi; Iwamoto, Osamu
J-PARC 17-07; J-PARC MLF Annual Report 2016, p.88 - 89, 2017/03
-ray analysisHuang, M.; Toh, Yosuke; Ebihara, Mitsuru*; Kimura, Atsushi; Nakamura, Shoji
Journal of Applied Physics, 121(10), p.104901_1 - 104901_7, 2017/03
Times Cited Count：2 Percentile：9.81(Physics, Applied)
Es and 
BkKonki, J.*; Khuyagbaatar, J.*; Uusitalo, J.*; Greenlees, P. T.*; Auranen, K.*; Badran, H.*; Block, M.*; Briselet, R.*; Cox, D. M.*; Dasgupta, M.*; et al.
Physics Letters B, 764, p.265 - 270, 2017/01
Times Cited Count：18 Percentile：79.1(Astronomy & Astrophysics)Naito, Fujio*; Anami, Shozo*; Ikegami, Kiyoshi*; Uota, Masahiko*; Ouchi, Toshikatsu*; Onishi, Takahiro*; Oba, Toshiyuki*; Obina, Takashi*; Kawamura, Masato*; Kumada, Hiroaki*; et al.
Proceedings of 13th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1244 - 1246, 2016/11
The proton linac installed in the Ibaraki Neutron Medical Research Center is used for production of the intense neutron flux for the Boron Neutron Capture Therapy (BNCT). The linac consists of the 3-MeV RFQ and the 8-MeV DTL. Design average beam current is 10mA. Target is made of Beryllium. First neutron production from the Beryllium target was observed at the end of 2015 with the low intensity beam as a demonstration. After the observation of neutron production, a lot of improvement s was carried out in order to increase the proton beam intensity for the real beam commissioning. The beam commissioning has been started on May 2016. The status of the commissioning is summarized in this report.
Zr(n,)Zr cross section with 
Zr(
O,
O)
Zr reactionsYan, S. Q.*; Li, Z. H.*; Wang, Y. B.*; Nishio, Katsuhisa; Makii, Hiroyuki; Su, J.*; Li, Y. J.*; Nishinaka, Ichiro; Hirose, Kentaro; Han, Y. L.*; et al.
Physical Review C, 94(1), p.015804_1 - 015804_5, 2016/07
Times Cited Count：6 Percentile：44.35(Physics, Nuclear)Abe, Shinichiro; Sato, Tatsuhiko
EPJ Web of Conferences, 122, p.04002_1 - 04002_6, 2016/06
Times Cited Count：0 Percentile：0.06(Physics, Nuclear)Nuclear transmutation has been investigated to reduce long-lived fission products (LLFPs) in high level radioactive wastes. However, the nuclear transmutation is difficult for some LLFPs (e.g., 
Sr, 
Sn and 
Cs) having small cross-sections of fission and neutron capture. Negative muon is examined to be applied for the nuclear transmutation. Low energy negative muon is captured on an atom, and then it can decay or be further captured on its nucleus. When negative muon is captured on nucleus, some light particles and residual nucleus are produced. Negative muon capture process has been implemented into latest version of PHITS. In this study, we studied the feasibility of nuclear transmutation by negative muon capture reaction for LLFPs using PHITS. Negative muon capture reaction on 90Sr is simulated. It is found that 94% of negative muons are captured on nucleus, and 66% of Sr become stable nuclides or radioactive nuclides having less than 20 days. It is also found that 15% of Sr become 
Rb having longer half-life than that of Sr.
