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La reactionOkuizumi, Mao*; Auton, C. J.*; Endo, Shunsuke; Fujioka, Hiroyuki*; Hirota, Katsuya*; Ino, Takashi*; Ishizaki, Kohei*; Kimura, Atsushi; Kitaguchi, Masaaki*; Koga, Jun*; et al.
Physical Review C, 111(3), p.034611_1 - 034611_6, 2025/03
Shimomura, Koichiro*; Koda, Akihiro*; Pant, A. D.*; Sunagawa, Hikaru*; Fujimori, Hiroshi*; Umegaki, Izumi*; Nakamura, Jumpei*; Fujihara, Masayoshi; Tampo, Motonobu*; Kawamura, Naritoshi*; et al.
Interactions (Internet), 245(1), p.31_1 - 31_6, 2024/12
Tazaki, Makiko; Kimura, Takashi; Shimizu, Ryo; Nakatani, Takayoshi; Suda, Kazunori
JAEA-Review 2023-042, 121 Pages, 2024/03
JAEA-Review-2023-042.pdf:3.01MB
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.
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
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
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
Chiba, Kaori*; Matsui, Takuro*; Chatake, Toshiyuki*; Ohara, Takashi; Tanaka, Ichiro*; Yutani, Katsuhide*; Niimura, Nobuo*
Protein Science, 32(10), p.e4765_1 - e4765_13, 2023/10
Times Cited Count：0 Percentile：0.00(Biochemistry & Molecular Biology)Mori, Takashi*; Shimada, Takahiro*; Kai, Satoru*; Otani, Akihito*; Yamamoto, Tomohiko; Yan, X.
Proceedings of ASME 2023 Pressure Vessels and Piping Conference (PVP 2023) (Internet), 8 Pages, 2023/07
Mori, Takashi*; Shimada, Takahiro*; Kai, Satoru*; Otani, Akihito*; Yamamoto, Tomohiko; Yan, X.
Proceedings of 30th International Conference on Nuclear Engineering (ICONE30) (Internet), 8 Pages, 2023/05
Hori, Masato; Tazaki, Makiko; Shimizu, Ryo; Kimura, Takashi; Nakatani, Takayoshi
Proceedings of INMM & ESARDA Joint Annual Meeting 2023 (Internet), 8 Pages, 2023/05
To improve preparedness of future denuclearization, series of study to achieve effective and efficient denuclearization have been performed in JAEA. As part of this study, this paper focus on dismantlement and verification of potential uranium enrichment facility and potential nuclear material in the uranium enrichment facility, considering (a) peaceful use operation, (b) freeze, (c) disablement, (d) dismantlement, (e) removal from the state as potential options.
Shimomura, Koichiro*; Koda, Akihiro*; Pant, A. D.*; Natori, Hiroaki*; Fujimori, Hiroshi*; Umegaki, Izumi*; Nakamura, Jumpei*; Tampo, Motonobu*; Kawamura, Naritoshi*; Teshima, Natsuki*; et al.
Journal of Physics; Conference Series, 2462, p.012033_1 - 012033_5, 2023/03
Times Cited Count：0 Percentile：0.00(Physics, Applied)Tazaki, Makiko; Kimura, Takashi; Shimizu, Ryo; Tamai, Hiroshi; Nakatani, Takayoshi; Suda, Kazunori
JAEA-Review 2022-056, 54 Pages, 2023/01
JAEA-Review-2022-056.pdf:1.86MB
As part of the "Research on Factor Analysis and Technical Processes for Achieving Denuclearization" South Africa's nuclear development and denuclearization cases were investigated then analyzed from seven denuclearization factors namely (1) motivation for nuclear development, (2) internal and external situations at the time of denuclearization decision, (3) progress of nuclear development, (4) effects of sanctions, (5) incentives for denuclearization, (6) international framework for denuclearization, (7) denuclearization and verification methods. At the same time, characteristics of its denuclearization and lessons learned from the denuclearization were also analyzed. South Africa shifted its nuclear activities from research and development of "peaceful nuclear detonation" in the 1970s to developing "limited nuclear deterrence" and finally to manufacturing "transportable nuclear weapons" in the late 1980s. By then, it had completed producing six nuclear explosive devices using highly enriched uranium. However, in 1989, along with the abolition of the apartheid policy, South Africa decided denuclearization and dismantled its nuclear explosive devices and related facilities. Upon completion of dismantlement, it joined the Treaty on the Non- Proliferation of Nuclear Weapons and concluded a Comprehensive Safeguards Agreement (CSA) with the International Atomic Energy Agency (IAEA). The South Africa has remained one of the rare countries that has continued to the peaceful use nuclear energy, and its voluntary denuclearization is considered as a good example of denuclearization in the future.
Nakatani, Takayoshi; Shimizu, Ryo; Tazaki, Makiko; Kimura, Takashi; Hori, Masato
Dai-43-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 4 Pages, 2022/11
Denuclearization is the verification of nuclear development and the freezing, disabling, decommissioning, and verification of nuclear weapons, nuclear materials that can be used for nuclear weapons, and their manufacturing facilities, equipment, equipment, and materials. In this study, the technical process of measures and verification methods to effectively and efficiently achieve denuclearization at nuclear installations is examined and considered from a technical point of view.
Shimizu, Ryo; Nakatani, Takayoshi; Tazaki, Makiko; Kimura, Takashi; Hori, Masato
Dai-43-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 3 Pages, 2022/11
no abstracts in English
Tazaki, Makiko; Nakatani, Takayoshi; Shimizu, Ryo; Kimura, Takashi; Hori, Masato
Dai-43-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 4 Pages, 2022/11
Denuclearization consists of (1) verification of nuclear activities prior to denuclearization, (2) freeze, disablement and decommissioning of nuclear weapons, nuclear materials such as HEU and Pu, their production facilities, including facilities and equipment, and their verification. In this study, as a premise for the denuclearization of nuclear materials and nuclear facilities, and with reference to the results of previous denuclearization case surveys and related literature, the denuclearization process and its options for technical measures are discussed and considered.
Hori, Masato; Tazaki, Makiko; Nakatani, Takayoshi; Shimizu, Ryo; Kimura, Takashi
Dai-43-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 4 Pages, 2022/11
no abstracts in English
Kimura, Takashi; Nakatani, Takayoshi; Shimizu, Ryo; Tazaki, Makiko; Hori, Masato
Dai-43-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 4 Pages, 2022/11
no abstracts in English
Tazaki, Makiko; Kimura, Takashi; Shimizu, Ryo; Tamai, Hiroshi; Nakatani, Takayoshi; Suda, Kazunori
JAEA-Review 2022-020, 82 Pages, 2022/09
JAEA-Review-2022-020.pdf:2.14MB
As part of the "Research on Factor Analysis and Technical Processes for Achieving Denuclearization" started in 2018, comprehensive survey of nuclear development and denuclearization of Iraq was conducted, together with analysis of the characteristics and lessons learned from the denuclearization. Iraq's clandestine nuclear weapon related activities were initially focused on plutonium production, but it then switched its focus on producing highly enriched uranium, and built various facilities, including electromagnetic isotope separation (EMIS) and centrifuge uranium enrichment facilities. Denuclearization of Iraq began with the defeat in the 1991 Gulf War, which forced Iraq to accept United Nations Security Council Resolution 687 (1991) that year. The Resolution set out a framework for destruction, removal, or rendering harmless of Iraq's weapons of mass destruction (WMD) programs. Within the framework, the International Atomic Energy Agency (IAEA), with the support and cooperation of the newly established United Nations Special Commission (UNSCOM), had verified Iraq's past nuclear activities and denuclearization. Characteristics of Iraq's denuclearization include that 1) Iraq had no choice but to accept denuclearization, 2) IAEA was empowered to implement detectable inspection measures and methods, which later came to fruition as the IAEA Safeguards Agreement Additional Protocol (AP), 3) economic sanctions for the purpose of promoting denuclearization of Iraq were not very successful, and 4) denuclearization of Iraq and subsequent Iraq war, together with collapse of the Hussein regime, has affected the denuclearization of Libya, North Korea and Iraq. Furthermore, the lessons learned from the denuclearization are 1) the need for universalization of AP, and necessities for 2) economic sanctions that are suitable for the original purposes without being abused, 3) the need for diplomatic efforts including denuclearization frameworks and measures with a clear roadmap
Murase, Kiyoka*; Kataoka, Ryuho*; Nishiyama, Takanori*; Nishimura, Koji*; Hashimoto, Taishi*; Tanaka, Yoshimasa*; Kadokura, Akira*; Tomikawa, Yoshihiro*; Tsutsumi, Masaki*; Ogawa, Yasunobu*; et al.
Journal of Space Weather and Space Climate (Internet), 12, p.18_1 - 18_16, 2022/06
Times Cited Count：3 Percentile：32.37(Astronomy & Astrophysics)We identified two energetic electron precipitation (EEP) events during the growth phase of moderate substorms and estimated the mesospheric ionization rate for an EEP event for which the most comprehensive dataset from ground-based and space-born instruments was available. The mesospheric ionization signature reached below 70 km altitude and continued for ~15 min until the substorm onset, as observed by the PANSY radar and imaging riometer at Syowa Station in the Antarctic region. We also used energetic electron flux observed by the Arase and POES 15 satellites as the input for the air-shower simulation code PHITS to quantitatively estimate the mesospheric ionization rate. Combining the cutting-edge observations and simulations, we shed new light on the space weather impact of the EEP events during geomagnetically quiet times, which is important to understand the possible link between the space environment and climate.
Tazaki, Makiko; Shimizu, Ryo; Kimura, Takashi; Tamai, Hiroshi; Nakatani, Takayoshi; Suda, Kazunori
JAEA-Review 2021-076, 108 Pages, 2022/03
JAEA-Review-2021-076.pdf:3.89MB
In order to find ways to lead the denuclearization successfully, effectively, and efficiently in the future, "Research on factor analysis and technical process for achieving denuclearization" has been conducted since 2018. This report covers the first half of the research, namely "Factor analysis for denuclearization", summarizing the results of the case study and factor analysis of denuclearization. First, South Africa, Iraq, Libya, Ukraine, Kazakhstan, Belarus, North Korea, Iran and Syria were selected as the initial research target countries, and the history of nuclear development as well as characteristics of denuclearization in each country were investigated and analyzed. Next, in order to consider the measures for the international community to lead the denuclearization of the target countries, eight main denuclearization factors ((1) Motivation for nuclear development, (2) Internal and external situation at the time of the denuclearization, (3) Progress of nuclear development, (4) Effects of sanctions, (5) International framework for denuclearization, (6) Incentives for denuclearization, (7) Denuclearization method, (8) Verification method/verifier) were found out. Finally, the contents of each denuclearization factor from (1) to (8)) in above target countries except Syria were analyzed, together with whether each factor was effective for denuclearization or not. In addition, in order to lead denuclearization effectively and efficiently, what should be done in relation to the eight factors were considered. These results are expected to serve as a basis for research on the technological process of denuclearization, and to help considering the way to accomplish denuclearization.
