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Be and 
Al under direct muon-induced spallation in granite quartz and its implications for past high-energy cosmic ray fluxesSakurai, Hirohisa*; Kurebayashi, Yutaka*; Suzuki, Soichiro*; Horiuchi, Kazuho*; Takahashi, Yui*; Doshita, Norihiro*; Kikuchi, Satoshi*; Tokanai, Fuyuki*; Iwata, Naoyoshi*; Tajima, Yasushi*; et al.
Physical Review D, 109(10), p.102005_1 - 102005_18, 2024/05
Secular variations of galactic cosmic rays (GCRs) are inseparably associated with the galactic activities and should reflect the environments of the local galactic magnetic field, interstellar clouds, and nearby supernova remnants. The high-energy muons produced in the atmosphere by high-energy GCRs can penetrate deep underground and generate radioisotopes in the rock. As long lived radionuclides such as Be and Al have been accumulating in these rocks, concentrations of Be and Al can be used to estimate the long-term variations in high-energy muon yields, corresponding to those in the high-energy GCRs over a few million years. This study measured the production cross sections for muon induced Be and Al by irradiating positive muons with the momentum of 160 GeV/c on the synthetic silica plates and the granite core at the COMPASS experiment line in CERN SPS. In addition, it the contributions of the direct muon spallation reaction and the nuclear reactions by muon-induced particles on the production of long lived radionuclides in the rocks were clarified.
Nakayama, Shinsuke; Furutachi, Naoya; Iwamoto, Osamu; Watanabe, Yukinobu*
NEA/NSC/R(2020)4 (Internet), p.345 - 349, 2022/10
Long-lived fission products (LLFPs) generated in nuclear reactors are strongly desired to be converted to stable or short-lived nuclides. Recently, it has been considered to transmute LLFPs by spallation reactions with high energy particles, and some experimental studies revealed that spallation reaction cross-sections induced by deuteron are larger than proton-induced ones. These results suggest the possibility that nuclear transmutation of LLFPs using deuteron beams is more efficient than one using proton beams. On the other hand, we have been developing a code system dedicated for deuteron-induced reactions, called DEURACS. DEURACS has been originally developed to contribute to the design of deuteron accelerator neutron sources. In the present study, we apply DEURACS to calculation of deuteron-induced spallation reactions on LLFPs. Through comparison with measured data, the applicability of DEURACS will be discussed.
Kanamura, Shohei*; Takahashi, Yuya*; Omori, Takashi*; Nohira, Toshiyuki*; Sakamura, Yoshiharu*; Matsumura, Tatsuro
Denki Kagaku, 88(3), p.289 - 290, 2020/09
no abstracts in English
Oshima, Masumi*; Yamaguchi, Yurie*; Asai, Masato; Tsukada, Kazuaki; Goto, Jun*; Bamba, Shigeru*; Bi, C.*; Morimoto, Takao*
Journal of Nuclear Science and Technology, 56(9-10), p.866 - 872, 2019/09
Times Cited Count：1 Percentile：10.65(Nuclear Science & Technology)Sensitivity of charged particle activation analysis with 8 MeV proton beam was studied for determination of 35 long-lived radioactive nuclides. Reaction cross sections for those nuclides were estimated with ALICE-91 code and isomer yield ratios were estimated from those of neighboring isotopes by taking into account their spins and parities. It was found that the proposed charged particle activation analysis should show high sensitivity for the determination of several hardly measurable nuclides with long half-lives such as 
Cs, 
Pu, 
I, 
Sn, 
Mo, 
Pd, 
U, 
Cm, and 
Np.
Morita, Keisuke; Suzuki, Hideya; Matsumura, Tatsuro; Takahashi, Yuya*; Omori, Takashi*; Kaneko, Masaaki*; Asano, Kazuhito*
Proceedings of International Nuclear Fuel Cycle Conference / Light Water Reactor Fuel Performance Conference (Global/Top Fuel 2019) (USB Flash Drive), p.464 - 468, 2019/09
High level liquid waste (HLLW) contains several radionuclides with half-lives longer than 10
year. For reduce environmental burden of waste disposal, minor actinoids and long-lived fission products will to be partitioned and transmuted. JAEA and Toshiba developed process for recovering Se, Zr, Pd and Cs from HLLW. Solvent extraction for Zr with novel extractant, 
-didodecyl-2-hydroxyacetoamide (HAA) was detailed. The HAA system showed high selectivity for Zr, as indicated by the extraction order of Zr 
Mo Pd Ag 
Sb Sn Lns Fe. The extracted species was determined as Zr(HAA)
(NO)
(HNO)
. A continuous countercurrent extraction with HAA was applied to a simulated, concentrated HLLW after Pd, Se, and Cs removal, where the quantitative extraction of Zr and Mo was effectively demonstrated.
Nishihara, Kenji
ImPACT Fujita Puroguramu Kokai Seika Hokokukai "Kaku Henkan Niyoru Koreberu Hoshasei Haikibutsu No Ohaba Na Teigen, Shigenka" Seika Hokokusho, Shiryoshu, p.28 - 31, 2019/03
In this project, long-lived fission products (LLFP) contained in conventional high-level radioactive wastes are separated and their life is reduced, and elements that can be used as resources are separated. By shortening the life of LLFP, it has been shown that it may be possible to dispose in intermediate depth of several tens of meters, meeting safety requirements, instead of geological disposal. In addition, for reassuring recycling of usable elements, possible exposure pathways were evaluated to estimate the safe concentration level of radioactivity.
Nishihara, Kenji
ImPACT Fujita Puroguramu Kokai Seika Hokokukai "Kaku Henkan Niyoru Koreberu Hoshasei Haikibutsu No Ohaba Na Teigen, Shigenka" Seika Hokokusho, Shiryoshu, p.130 - 133, 2019/03
High level radioactive waste contains elements with various characteristics. It is possible to reduce the load on the disposal site by separating them according to those characteristics and appropriately dealing with them. In this project, we are working to shorten the life span of long-lived fission products (LLFP). When this technology is realized, high-level radioactive wastes will become new radioactive wastes with low radioactivity. As a result of investigation of disposal concept of new radioactive waste, it turned out that intermediate-depth disposal currently considered for low level radioactive waste may be suitable. Intermediate-depth disposal is a method of small-scale disposal in shallow locations as compared to geological disposal for conventional high-level radioactive waste. We conducted a safety assessment when this disposal is applied to new radioactive wastes, and found that it is possible to safely dispose of for the four LLFPs addressed by this project.
Nishihara, Kenji
Genshiryoku Bakkuendo Kenkyu (CD-ROM), 25(2), p.131 - 134, 2018/12
Impact of reduction of source term on design and safety assessment of disposal concept for high level radioactive waste is considered. Reduction of source term in partitioning and transmutation technology is shown with impact on disposal concept. Moreover, cost and technological readiness is outlined.
Nakayama, Shinsuke; Furutachi, Naoya; Iwamoto, Osamu; Watanabe, Yukinobu*
Physical Review C, 98(4), p.044606_1 - 044606_8, 2018/10
Times Cited Count：14 Percentile：75.2(Physics, Nuclear)Use of deuteron-induced spallation reactions at intermediate energies has recently been proposed for transmutation of several long-lived fission products (LLFPs). In the design study of a transmutation system using a deuteron primary beam, accurate cross section data of deuteron-induced reactions on the LLFPs are indispensable. In the present study, production cross sections of residual nuclei in the deuteron-induced reactions on Zr and Pd at 
MeV/nucleon are analyzed using DEURACS, in which the breakup processes are explicitly taken into account. The calculated values reproduced the experimental data quantitatively well. From a component-by-component analysis, it was found that the components of nucleon absorption make the significant contributions to residual nuclei production. This result strongly indicates that consideration of the breakup processes is essentially important to predict production of residual nuclei in deuteron-induced reactions.
Chiba, Satoshi*; Wakabayashi, Toshio*; Tachi, Yoshiaki; Takaki, Naoyuki*; Terashima, Atsunori*; Okumura, Shin*; Yoshida, Tadashi*
Scientific Reports (Internet), 7(1), p.13961_1 - 13961_10, 2017/10
Times Cited Count：36 Percentile：96.56(Multidisciplinary Sciences)Transmutation of long-lived fission products (LLFPs: 
Se, Zr, 
Tc, Pd, I, and Cs) into short-lived or non-radioactive nuclides by fast neutron spectrum reactors without isotope separation has been proposed as a solution to the problem of radioactive wastes disposal. Despite investigation of many methods, such transmutation remains technologically difficult. To establish an effective and efficient transmutation system, we propose a novel neutron moderator material, yttrium deuteride (YD
), to soften the neutron spectrum leaking from the reactor core. Neutron energy spectra and effective half-lives of LLFPs, transmutation rates, and support ratios were evaluated with the continuous-energy Monte Carlo code MVP-II/MVP-BURN and the JENDL-4.0 cross section library. With the YD moderator in the radial blanket and shield regions, effective half-lives drastically decreased from 10 to 10
years and the support ratios reached 1.0 for all six LLFPs. This successful development and implementation of a transmutation system for LLFPs without isotope separation contribute to developing a self-consuming cycle of LLFPs using fast spectrum reactors to reduce radioactive waste.
Minato, Kazuo; Tsujimoto, Kazufumi; Tanabe, Hiromi*; Fujimura, Koji*
Nihon Genshiryoku Gakkai-Shi ATOMO
, 59(8), p.475 - 479, 2017/08
no abstracts in English
Kimura, Atsushi; Harada, Hideo; Nakamura, Shoji; Iwamoto, Osamu; Toh, Yosuke; Koizumi, Mitsuo; Kitatani, Fumito; Furutaka, Kazuyoshi; Igashira, Masayuki*; Katabuchi, Tatsuya*; et al.
European Physical Journal A, 51(12), p.180_1 - 180_8, 2015/12
Times Cited Count：3 Percentile：30.26(Physics, Nuclear)Oigawa, Hiroyuki; Nishihara, Kenji; Minato, Kazuo; Kimura, Takaumi; Arai, Yasuo; Morita, Yasuji; Nakayama, Shinichi; Katakura, Junichi
JAERI-Review 2005-043, 193 Pages, 2005/09
JAERI-Review-2005-043.pdf:16.13MB
JAERI has been conducting research and development on partitioning and transmutation (P&T) technology for long-lived nuclides to develop the double-strata fuel cycle concept, in accordance with the Atomic Energy Commission's "Research and Development of Technologies for Partitioning and Transmutation of Long-lived Nuclides - Status and Evaluation Report" issued in 2000. The double-strata fuel cycle concept consists of four major processes: partitioning, fuel fabrication, transmutation, and fuel processing. The five-year achievement and future perspectives for the technology on these processes are presented in this report. It also provides an analytical study on impacts of introducing P&T technology on waste management, and on deployment of P&T for the future nuclear energy system.
Morita, Yasuji
Genshikaku Kenkyu, 47(6), p.21 - 30, 2003/06
This paper describes the present state and future prospect of research and development on the separation of long-lived radionuclides from high-level waste (partitioning), which is indispensable for the transmutation of those nuclides. The main items described are composition of high-level waste, selection of elements to be separated, the purpose of partitioining, and development of partitioning process in JAERI.
Sawa, Kazuhiro; Yamashita, Toshiyuki; Minato, Kazuo; Arai, Yasuo; Konashi, Kenji*
Nihon Genshiryoku Gakkai-Shi, 44(9), p.657 - 662, 2002/09
no abstracts in English
Morimoto, Kyoichi; Shibata, Atsuhiro; Shigetome, Yoshiaki
JNC TN8200 2001-006, 19 Pages, 2001/12
JNC-TN8200-2001-006.pdf:0.92MB
Global2001 (International Conference: "Back-End of the Fuel Cycle: From Research to Solutions ") was held for six days from September 9 to September 14 in Paris in France. In this year, there were about 420 participants from each country and about 70 people participated from Japan. This conference consisted of the reactor and fuel cycle field, the reprocessing field, the disposal field, and the non-proliferation field, etc. The main topics of this conference were the back end of the nuclear fuel cycle, the management of long-lived nuclide, the advanced concept of reactor and fuels. Advanced fuel recycle technology division reported about the feasibility study on commercialized FR cycle systems, the nuclear fuel and the reprocessing process in the oral session and poster session. Each report was audited and information was collected. It is possible to refer to information on Global2001 by the following homepages. http://www.cea.fr/conferences/global2001 /index.him*
Mukaiyama, Takehiko
Genshikaku Kenkyu, 46(2), p.47 - 73, 2001/06
no abstracts in English
Shelley, A.*; Akie, Hiroshi; Takano, Hideki; Sekimoto, Hiroshi*
Journal of Nuclear Science and Technology, 38(2), p.134 - 142, 2001/02
no abstracts in English
Mukaiyama, Takehiko; Takizuka, Takakazu; Mizumoto, Motoharu; Ikeda, Yujiro; Ogawa, Toru; Hasegawa, Akira; Takada, Hiroshi; Takano, Hideki
Progress in Nuclear Energy, 38(1-2), p.107 - 134, 2001/02
Times Cited Count：68 Percentile：96.97(Nuclear Science & Technology)no abstracts in English
Funasaka, Hideyuki; ;
JNC TN1200 2001-002, 209 Pages, 2001/01
JNC-TN1200-2001-002.pdf:7.84MB
no abstracts in English
