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Pohl, T.*; Sun, Y. L.*; Obertelli, A.*; Lee, J.*; Gmez-Ramos, M.*; Ogata, Kazuyuki*; Yoshida, Kazuki; Cai, B. S.*; Yuan, C. X.*; Brown, B. A.*; et al.
Physical Review Letters, 130(17), p.172501_1 - 172501_8, 2023/04
Times Cited Count:5 Percentile:92.42(Physics, Multidisciplinary)We report on the first proton-induced single proton- and neutron-removal reactions from the neutron deficient O nucleus with large Fermi-surface asymmetry at 100 MeV/nucleon. Our results provide the first quantitative contributions of multiple reaction mechanisms including the quasifree knockout, inelastic scattering, and nucleon transfer processes. It is shown that the inelastic scattering and nucleon transfer, usually neglected at such energy regime, contribute about 50% and 30% to the loosely bound proton and deeply bound neutron removal, respectively.
Ikeuchi, Hirotomo; Koyama, Shinichi; Osaka, Masahiko; Takano, Masahide; Nakamura, Satoshi; Onozawa, Atsushi; Sasaki, Shinji; Onishi, Takashi; Maeda, Koji; Kirishima, Akira*; et al.
JAEA-Technology 2022-021, 224 Pages, 2022/10
A set of technology, including acid dissolving, has to be established for the analysis of content of elements/nuclides in the fuel debris samples. In this project, a blind test was performed for the purpose of clarifying the current level of analytical accuracy and establishing the alternative methods in case that the insoluble residue remains. Overall composition of the simulated fuel debris (homogenized powder having a specific composition) were quantitatively determined in the four analytical institutions in Japan by using their own dissolving and analytical techniques. The merit and drawback for each technique were then evaluated, based on which a tentative flow of the analyses of fuel debris was constructed.
Yang, Z. H.*; Kubota, Yuki*; Corsi, A.*; Yoshida, Kazuki; Sun, X.-X.*; Li, J. G.*; Kimura, Masaaki*; Michel, N.*; Ogata, Kazuyuki*; Yuan, C. X.*; et al.
Physical Review Letters, 126(8), p.082501_1 - 082501_8, 2021/02
Times Cited Count:43 Percentile:96.7(Physics, Multidisciplinary)A quasifree (,) experiment was performed to study the structure of the Borromean nucleus B, which had long been considered to have a neutron halo. By analyzing the momentum distributions and exclusive cross sections, we obtained the spectroscopic factors for and orbitals, and a surprisingly small percentage of 9(2)% was determined for . Our finding of such a small component and the halo features reported in prior experiments can be explained by the deformed relativistic Hartree-Bogoliubov theory in continuum, revealing a definite but not dominant neutron halo in B. The present work gives the smallest - or -orbital component among known nuclei exhibiting halo features and implies that the dominant occupation of or orbitals is not a prerequisite for the occurrence of a neutron halo.
Nakamura, Satoshi; Kimura, Takahiro; Ban, Yasutoshi; Tsubata, Yasuhiro; Matsumura, Tatsuro
JAEA-Technology 2020-009, 22 Pages, 2020/08
Partitioning and transmutation technology division is planning to measure fission rate ratios that contribute to validate nuclear data of minor actinides (MA). For this purpose, MA sources for fission chambers were prepared using electrodeposition method. The radioactivity of each MA source was quantified, and its uncertainty was evaluated. Seven types of MA sources with different radioactivity were prepared using four nuclides of Np, Am, Am, and Cm. A Cm source solution of which radioactivity was quantified by isotope dilution method was used to prepare working standard sources of Cm. The radioactivities were quantified as 1461 Bq, 2179 Bq, and 2938 Bq for Np sources, 1.428 MBq for Am source, 370.5 kBq and 89.57 kBq for Am sources, and 2.327 MBq for Cm source with, the uncertainty of 0.35% (1). This report summarizes the method for preparation and quantification of MA sources, and uncertainty evaluation.
Nakamura, Satoshi; Kimura, Takahiro; Ban, Yasutoshi; Matsumura, Tatsuro; Oizumi, Akito; Fukushima, Masahiro; Tsubata, Yasuhiro; Hayashi, Hirokazu
no journal, ,
no abstracts in English
Nakamura, Satoshi; Ishii, Sho*; Ban, Yasutoshi; Matsumura, Tatsuro; Sugimoto, Mie; Fukaya, Hiroyuki; Takano, Masahide
no journal, ,
no abstracts in English
Nakamura, Satoshi; Ban, Yasutoshi; Sugimoto, Mie; Tambo, Masaki; Fukaya, Hiroyuki; Hiruta, Kenta; Yoshida, Takuya; Uehara, Hiroyuki; Obata, Hiroki; Kimura, Yasuhiko; et al.
no journal, ,
In Nuclear Science Research Institute at JAEA, detailed studies with regard to the elemental and nuclide compositions of fuel debris have been proceeding. We have conducted dissolution of the samples by alkaline fusion with sodium peroxide and chemical analysis by ICP-AES, alpha and gamma spectrometer, and TIMS. After studying the dissolution methods with various types of simulated debris, a demonstration test with TMI-2 debris was conducted. The elemental composition in the dissolved solution of TMI-2 debris consistent with the results of SEM/WDX and XRD analyses, and the validity of the present method was confirmed. In this presentation, the details of each analysis and the issues raised through the analysis will be introduced.
Suzuki, Hideya*; Shimojo, Kojiro; Nakamura, Satoshi; Emori, Tatsuya; Kurosawa, Tatsuya*; Shibata, Mitsunobu*; Kawasaki, Tomohiro*; Ban, Yasutoshi
no journal, ,
The Japan Atomic Energy Agency (JAEA) has been studying partitioning and transmutation (P&T) systems. In P&T, JAEA proposed a novel hydrometallurgical process called "SELECT (Solvent Extraction from Liquid waste using Extractants of CHON-type for Transmutation) process" for nuclear fuel reprocessing and minor actinides (MA) separation. In this study, a new MA separation method was investigated to further improve the efficiency of the SELECT process. Batch tests were conducted in a mixed solvent system using the acidic amide-type extractants nitrilotriacetic acid diacetamide with branched side chains (B-TONAADA) and alkyl diamidoamine (ADAAM). As a result, we found an efficient method for separating only americium (Am) from an aqueous nitric acid solution containing MA and rare earth elements by adjusting nitric acid concentration.
Nakamura, Satoshi; Suzuki, Hideya*; Ishii, Sho*; Emori, Tatsuya; Kurosawa, Tatsuya*; Shibata, Mitsunobu*; Shimojo, Kojiro; Ban, Yasutoshi
no journal, ,
To reduce volume and radiotoxicity of high-level radioactive waste, JAEA has been developing a separation process called "SELECT" (Solvent Extraction from Liquid-waste using Extractants of CHON-type for Transmutation) for recovering minor actinides (MA) from high-level radioactive liquid-waste. In this study, the applicability of an acidic diamide-type extractant Branched-TetraOctylNitriloAceticAcidDiAmide (B-TONAADA) was investigated with a view to improving the efficiency of MA/Rare Earth Elements (RE) separation in SELECT process. As a results of extraction tests performed with different nitric acid concentrations, specific changes were observed in the lanthanide patterns of distribution ratios, and the distribution ratios of MA were higher than those of RE over a wide range of nitric acid concentrations.
Suzuki, Hideya*; Nakamura, Satoshi; Emori, Tatsuya; Kurosawa, Tatsuya*; Shibata, Mitsunobu*; Kawasaki, Tomohiro*; Ban, Yasutoshi
no journal, ,
The Japan Atomic Energy Agency (JAEA) has been studying partitioning and transmutation systems (P&T). In P&T, JAEA proposed a novel hydrometallurgical process called "SELECT (Solvent Extraction from Liquid waste using Extractants of CHON-type for Transmutation) process". In the SELECT process, HexaOctyl NitriloTriacetAmide (HONTA) with six -octyl side chains is used for the mutual separation of minor actinides (MA) and rare earth elements (RE). In the present study, extraction tests were carried out with HONTA and three nitrilotriacetamides (NTA amides) with different side chains. The results show that the different side chains of NTA amides affect the extraction behaviors of MA and RE.