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Saito, Shigeru; Meigo, Shinichiro; Makimura, Shunsuke*; Hirano, Yukinori*; Tsutsumi, Kazuyoshi*; Maekawa, Fujio
JAEA-Technology 2023-025, 48 Pages, 2024/03
JAEA has been developing Accelerator-Driven Systems (ADS) for research and development of nuclear transmutation using accelerators in order to reduce the volume and hazardousness of high-level radioactive waste generated by nuclear power plants. In order to prepare the material irradiation database necessary for the design of ADS and to study the irradiation effects in Lead-Bismuth Eutectic (LBE) alloys, a proton irradiation facility is under consideration at J-PARC. In this proton irradiation facility, 250 kW proton beams will be injected into the LBE spallation target, and irradiation tests under LBE flow will be performed for candidate structural materials for ADS. Furthermore, semiconductor soft-error tests, medical RI production, and proton beam applications will be performed. Among these, Post Irradiation Examination (PIE) of irradiated samples and RI separation and purification will be carried out in the PIE facility to be constructed near the proton irradiation facility. In this PIE facility, PIE of the equipment and samples irradiated in other facilities in J-PARC will also be performed. This report describes the conceptual study of the PIE facility, including the items to be tested, the test flow, the facilities, the test equipment, etc., and the proposed layout of the facility.
Tazaki, Makiko; Kimura, Takashi; Shimizu, Ryo; Nakatani, Takayoshi; Suda, Kazunori
JAEA-Review 2023-042, 121 Pages, 2024/03
As part of the "Research on Factor Analysis and Technical Processes for Achieving Denuclearization", we investigated denuclearization cases in three former Soviet Union countries, namely Belarus, Kazakhstan, and Ukraine, and analyzed the cases by eight denuclearization factors. We then considered the characteristics and lessons learned from such denuclearization. The denuclearization processes of the three countries differed from country to country, and Ukraine's denuclearization process in particular went through many twists and turns. However, the common factor was that all nuclear-weapon states provided security assurances to the three countries and as a result, they transferred strategic nuclear weapons to Russia and joined the Nuclear Non-proliferation Treaty (NPT) as non-nuclear weapon states. Such decision was partly made possible by the economic and physical assistance provided by the United States and Russia for denuclearization. Furthermore, one of the characteristics of the denuclearization of the three countries is the US's skillful denuclearization strategy toward the three countries. The United States supported the claims that the three countries, like Russia, were parties to the First Strategic Arms Reduction Treaty (START-I), and ultimately allowed them to transfer strategic nuclear warheads to Russia within the framework of START-I and the subsequently achieved the disposal of the warheads in Russia. Furthermore, as a lesson from the denuclearization of the three countries, providing security assurance to denuclearized countries is a strong incentive for denuclearization. However, considering Russia's annexation of Crimea in 2014 and military invasion of Ukraine in February 2022, countries which are required denuclearization will seek stronger security guarantees from nuclear-weapon states. Another lesson is that it is necessary to have a strong presidential initiative the countries concerned.
Fujita, Natsuko; Miyake, Masayasu; Matsubara, Akihiro*; Ishii, Masahiro*; Watanabe, Takahiro; Jinno, Satoshi; Nishio, Tomohiro*; Ogawa, Yumi; Kimura, Kenji; Shimada, Akiomi; et al.
Dai-35-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.17 - 19, 2024/03
The JAEA-AMS-TONO facility at the Tono Geoscience Center, JAEA has three accelerator mass spectrometers. We report the present status of the JAEA-AMS-TONO.
Hokama, Tomonori; Kimura, Masanori; Togawa, Orihiko
JAEA-Research 2023-010, 57 Pages, 2024/02
In the case of a nuclear accident, itis planned to perform simple measurement of radioactive iodine radioactivity in the thyroid of residents. The screening level for simple measurement is set at 0.20 Sv/h as a reference, and it is required to be reviewed appropriately according to the situation such as a nuclear accident. However, a specific method for reviewing the screening level is not shown. When reviewing the screening level, it is important to take into account factors related to the feasibility of simple measurement, such as the judgment level for internal exposure dose of the thyroid and the duration of the measurement period. In this study, we organized the derivation process of 0.20 Sv/h, which was set as the reference for screening level, and considered the feasibility of the reviewing of screening level. We calculated the relationship between the judgment level and the duration of simple measurement for each screening level, ranging from 0.025 to 0.50 Sv/h. Then, the feasibility of the reviewing of screening level was considered. It was found that reviewing the screening level is technically feasible, provided that the judgment level and the duration of simple measurement are appropriate. However, assuming that simple measurement will be performed in an actual nuclear accident, we assessed that it would be reasonable to review the screening level within the range of 0.030 to 0.20 Sv/h, in a situation where the duration of simple measurement must be extended.
Shigyo, Nobuhiro*; Kimura, Atsushi; Sano, Tadafumi*
JAEA-Conf 2023-001, 146 Pages, 2024/02
The 2022 Symposium on Nuclear Data was held at BLOSSOM CAF in Main Campus of Kindai University on November 17-18, 2022. The symposium was organized by the Nuclear Data Division of the Atomic Energy Society of Japan (AESJ) in cooperation with Investigation Committee on Nuclear Data in AESJ, Nuclear Science and Engineering Center of Japan Atomic Energy Agency, and High Energy Accelerator Research Organization. In the symposium, tutorials "The Future of Nuclear Reactor Physics Experimental Research in Japan" was proposed and held. Two sessions of lectures and discussions were held: "Recent Topics on Nuclear Data". In addition, recent research progress on experiments, nuclear theory, evaluation, benchmark, and applications were presented in the poster session. The total number of participants was 76 participants. Each oral and poster presentation was followed by an active question and answer session. This report consists of a total of 22 papers including 4 oral and 18 poster presentations.
Yamauchi, Hiroki; Sari, D. P.*; Yasui, Yukio*; Sakakura, Terutoshi*; Kimura, Hiroyuki*; Nakao, Akiko*; Ohara, Takashi; Honda, Takashi*; Kodama, Katsuaki; Igawa, Naoki; et al.
Physical Review Research (Internet), 6(1), p.013144_1 - 013144_9, 2024/02
Omokawa, Marina*; Kimura, Hiroyuki*; Hatsukawa, Yuichi*; Kawashima, Hidekazu*; Tsukada, Kazuaki; Yagi, Yusuke*; Naito, Yuki*; Yasui, Hiroyuki*
Bioorganic & Medicinal Chemistry, 97, p.117557_1 - 117557_6, 2024/01
Times Cited Count:0 Percentile:0.01(Biochemistry & Molecular Biology)Utsunomiya, Hiroaki*; Goriely, S.*; Kimura, Masaaki*; Shimizu, Noritaka*; Utsuno, Yutaka; Tveten, G. M.*; Renstrm, T.*; Ariizumi, Takashi*; Miyamoto, Shuji*
Physical Review C, 109(1), p.014617_1 - 014617_7, 2024/01
no abstracts in English
Fuyushima, Takumi; Takabe, Yugo; Sayato, Natsuki; Kimura, Akihiro; Takemoto, Noriyuki
The IV International Scientific Forum "Nuclear Science and Technologies"; AIP Conference Proceedings 3020, p.040007_1 - 040007_6, 2024/01
We studied irradiation tests of structural materials simulating fast reactor conditions in JMTR. We fabricated capsules that can simulate fast reactor irradiation in JMTR by using He/dpa ratio as index. To simulate fast reactor, cadmium, which shield thermal neutrons, was placed inside the capsule to adjust the neutron spectrum. According to the result of irradiation tests by neutron spectrum adjusting capsule, we confirmed that it can simulate the He/dpa ratio of fast reactor. Currently, since it is impossible to conduct irradiation tests in Japan, a plan is underway to partly replace the irradiation function of JMTR with overseas reactors. The alternative irradiation will be carried out by succeeding and developing the irradiation technology accumulated in the JMTR, and as a part of this, a trial of such irradiation in which the neutron spectrum is adjusted is under consideration.
Dohi, Terumi; Iijima, Kazuki; Machida, Masahiko; Suno, Hiroya*; Omura, Yoshihito*; Fujiwara, Kenso; Kimura, Shigeru*; Kanno, Futoshi*
Environmental radiochemical analysis VII, p.50 - 57, 2023/12
Endo, Shunsuke; Kawamura, Shiori*; Okudaira, Takuya*; Yoshikawa, Hiromoto*; Rovira Leveroni, G.; Kimura, Atsushi; Nakamura, Shoji; Iwamoto, Osamu; Iwamoto, Nobuyuki
European Physical Journal A, 59(12), p.288_1 - 288_12, 2023/12
Times Cited Count:0 Percentile:0.02(Physics, Nuclear)no abstracts in English
Nakatani, Takayoshi; Shimizu, Ryo; Tazaki, Makiko; Kimura, Takashi; Hori, Masato
Dai-44-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 3 Pages, 2023/11
no abstracts in English
Tazaki, Makiko; Kimura, Takashi; Shimizu, Ryo; Nakatani, Takayoshi
Dai-44-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 4 Pages, 2023/11
no abstracts in English
Shimizu, Ryo; Nakatani, Takayoshi; Tazaki, Makiko; Kimura, Takashi; Hori, Masato
Dai-44-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 4 Pages, 2023/11
no abstracts in English
Nakamura, Shoji; Shibahara, Yuji*; Endo, Shunsuke; Kimura, Atsushi
Journal of Nuclear Science and Technology, 60(11), p.1361 - 1371, 2023/11
Times Cited Count:1 Percentile:72.91(Nuclear Science & Technology)The thermal-neutron capture cross section () and resonance integral (I) for Nb among nuclides for decommissioning were measured by an activation method and the half-life of Nb by mass analysis. Niobium-93 samples were irradiated with a hydraulic conveyer installed in the research reactor in Institute for Integral Radiation and Nuclear Science, Kyoto University. Gold-aluminum, cobalt-aluminum alloy wires were used to monitor thermal-neutron fluxes and epi-thermal Westcott's indexes at an irradiation position. A 25-m-thick gadolinium foil was used to sort out reactions ascribe to thermal-and epi-thermal neutrons. Its thickness provided a cut-off energy of 0.133 eV. In order to attenuate radioactivity of Ta due to impurities, the Nb samples were cooled for nearly 2 years. The induced radio activity in the monitors and Nb samples were measured by -ray spectroscopy. In analysis based on Westcott's convention, the and I values were derived as 1.110.04 barn and 10.50.6 barn, respectively. After the -ray measurements, mass analysis was applied to the Nb sample to obtain the reaction rate. By combining data obtained by both -ray spectroscopy and mass analysis, the half-life of Nb was derived as (2.000.15)10 years.
Matsumura, Daiju; Kimura, Yusaku*; Tsuji, Takuya; Mizuki, Junichiro*
SPring-8/SACLA Riyo Kenkyu Seikashu (Internet), 11(5), p.296 - 299, 2023/11
no abstracts in English
Kido, Eiji*; Inakura, Tsunenori*; Kimura, Masaaki*; Kobayashi, Nobuyuki*; Nagataki, Shigehiro*; Shimizu, Noritaka*; Tamii, Atsushi*; Utsuno, Yutaka
Astroparticle Physics, 152, p.102866_1 - 102866_12, 2023/10
Times Cited Count:1 Percentile:0.01(Astronomy & Astrophysics)no abstracts in English
Iwamoto, Osamu; Iwamoto, Nobuyuki; Kimura, Atsushi; Tada, Kenichi; Yokoyama, Kenji
Kaku Deta Nyusu (Internet), (136), 6 Pages, 2023/10
no abstracts in English
Tamii, Atsushi*; Pellegri, L.*; Sderstrm, P.-A.*; Allard, D.*; Goriely, S.*; Inakura, Tsunenori*; Khan, E.*; Kido, Eiji*; Kimura, Masaaki*; Litvinova, E.*; et al.
European Physical Journal A, 59(9), p.208_1 - 208_21, 2023/09
Times Cited Count:1 Percentile:0.02(Physics, Nuclear)no abstracts in English
Ukai, Shigeharu; Sakamoto, Kan*; Otsuka, Satoshi; Yamashita, Shinichiro; Kimura, Akihiko*
Journal of Nuclear Materials, 583, p.154508_1 - 154508_24, 2023/09
Times Cited Count:5 Percentile:94.3(Materials Science, Multidisciplinary)