Improved multicomponent analysis method for electron spin resonance spectra of gamma-irradiated tooth enamel

Yamashita, Takuma*; Iwami, Satone*; Mitsuyasu, Yusuke*; Ono, Kenta*; Oka, Toshitaka; Takahashi, Atsushi*; Kino, Yasushi*; Sekine, Tsutomu*; Shimizu, Yoshinaka*; Chiba, Mirei*; et al.

KEK Proceedings 2024-6, p.85 - 90, 2024/12

To clarify the radiation effects of the accident at the TEPCO's Fukushima Daiichi NPP on living organisms, it is important to accurately estimate the dose to each individual. We have developed a multi-component analysis program using random number optimization to extract only the components derived from carbonate radicals from the ESR spectra.

Development of nuclear data processing code FRENDY version 2

Tada, Kenichi; Yamamoto, Akio*; Kunieda, Satoshi; Konno, Chikara; Kondo, Ryoichi; Endo, Tomohiro*; Chiba, Go*; Ono, Michitaka*; Tojo, Masayuki*

Journal of Nuclear Science and Technology, 61(6), p.830 - 839, 2024/06

https://doi.org/10.1080/00223131.2023.2278600

Nuclear data processing code is important to connect evaluated nuclear data libraries and radiation transport codes. The nuclear data processing code FRENDY version 1 was released in 2019 to generate ACE formatted cross section files with simple input data. After we released FRENDY version 1, many functions were developed, e.g., neutron multi-group cross section generation, explicit consideration of the resonance interference effect among different nuclides in a material, consideration of the resonance upscattering, ACE file perturbation, and modification of ENDF-6 formatted file. FRENDY version 2 was released including these new functions. It generates GENDF and MATXS formatted neutron multi-group cross section files from an ACE formatted cross section file or an evaluated nuclear data file. This paper explains the features of the new functions implemented in FRENDY version 2 and the verification of the neutron multigroup cross section generation function of this code.

Dependence of the average total kinetic energy of fission fragments on incident neutron energy studied by a 4D Langevin model

Shimada, Kazuya; Ishizuka, Chikako*; Chiba, Satoshi*

Proceedings of 12th International Conference on Nuclear Criticality Safety (ICNC2023) (Internet), 9 Pages, 2023/10

TKE (total kinetic energy), one of the nuclear data, is the kinetic energy of fission fragments, and influences not only the energy obtained in nuclear fission, but also the criticality safety assessment. Exploring the underlying factors influencing TKE is vital for fundamental research and utilization of nuclear energy. Instinctively, it is expected that as the energy of incident neutrons on the target nucleus increases, thus leading to a corresponding increase in TKE. However, experimental evidence suggests that TKE decreases as the excitation energy increases. In this study, we investigate this phenomenon. The four-dimensional Langevin model captures the overall shape of the nuclear fission fragment as Brownian motion until the nuclear fission. Using this model, we calculated the excitation energy dependence of TKE. Our investigation reveals that the decreasing trend in TKE can be attributed to the deformation of the heavy fission fragments.

Collaboration with Dr. Efrem Sh. Soukhovitsukii; Our fortuitous experiences on optical model analysis, his contribution to nuclear data activities of Japan and a posthumous study on light-nuclei

Kunieda, Satoshi; Iwamoto, Osamu; Fukahori, Tokio; Chiba, Satoshi*

European Physical Journal A, 59(1), p.2_1 - 2_8, 2023/01

https://doi.org/10.1140/epja/s10050-022-00907-3

Optical model or coupled-channels calculation serves as an entrance to sophisticated calculation of nuclear data. It was a great contribution of Dr. Efrem Sh. Soukhovitsukii who has developed an excellent computation scheme which takes account of the low-lying collective nuclear structure in terms of the soft-rotator + vibrational model, and integrated it into the coupled-channels calculation. In Japan, we had a fortuitous experience with him in parametrization of the optical model potential (OMP) and to employ this methodology in nuclear data evaluation for JENDL. Firstly, we summarize our collaborative works with him in this paper. Secondly, let us have a discussion on a new parameterization of OMP which we obtained for light nuclei within his framework, quite recently. It was found that values of the potential parameters themselves are rather similar among different nuclei while the nuclear deformation describes one of the main characteristics of each isotopes.

A Study on accuracy of analysis of the radiation-induced component in the ESR spectra of teeth

Mitsuyasu, Yusuke*; Oka, Toshitaka; Takahashi, Atsushi*; Kino, Yasushi*; Okutsu, Kenichi*; Sekine, Tsutomu*; Yamashita, Takuma*; Shimizu, Yoshinaka*; Chiba, Mirei*; Suzuki, Toshihiko*; et al.

KEK Proceedings 2022-2, p.120 - 125, 2022/11

We investigate the effect of sample's anisotropy and measurement condition to obtain the higher reproducibility for the shape of the ESR spectrum and the intensity of CO radical.

Isomer production ratio of the Cd()Cd reaction in an -process branching point

Hayakawa, Takehito*; Toh, Yosuke; Kimura, Atsushi; Nakamura, Shoji; Shizuma, Toshiyuki*; Iwamoto, Nobuyuki; Chiba, Satoshi*; Kajino, Toshitaka*

Physical Review C, 103(4), p.045801_1 - 045801_5, 2021/04

https://doi.org/10.1103/PhysRevC.103.045801

Evaluation of fission product yields and associated covariance matrices

Tsubakihara, Kosuke*; Okumura, Shin*; Ishizuka, Chikako*; Yoshida, Tadashi*; Minato, Futoshi; Chiba, Satoshi*

Journal of Nuclear Science and Technology, 58(2), p.151 - 165, 2021/02

AA2020-0468.pdf:2.37MB

https://doi.org/10.1080/00223131.2020.1813643

Proceedings of the 2018 Symposium on Nuclear Data; November 29-30, 2018, Tokyo Institute of Technology, Ookayama Campus, Tokyo, Japan

Chiba, Satoshi*; Ishizuka, Chikako*; Tsubakihara, Kosuke*; Iwamoto, Osamu

JAEA-Conf 2019-001, 203 Pages, 2019/11

JAEA-Conf-2019-001.pdf:18.86MB

The 2018 Symposium on Nuclear Data was held at Multi-Purpose Digital Hall and Collaboration Room of Tokyo Institute of Technology, on November 29 and 30, 2018. The symposium was organized by the Nuclear Data Division of the Atomic Energy Society of Japan (AESJ) in cooperation with Sigma Special Committee of AESJ, Nuclear Science and Engineering Center of Japan Atomic Energy Agency, and Laboratory for Advanced Nuclear Energy of Institute of Innovative Research, Tokyo Institute of Technology. In the symposium, there were one tutorial, "Development of nuclear data processing code FRENDY", one special lecture "What the future holds for Nuclear Energy" and seven oral sessions, "Nuclear Data and Future Perspectives", "Current Status and Future Perspectives of Reactor Physics", "Topics", "Nuclear Data Applications", "International Session", "Nuclear Data Measurements and New Technology for Nuclear Reactor Diagnosis", and "Data Needs from New Fields". In addition, recent research progress on experiments, evaluation, benchmark and application was presented in the poster session. Among 82 participants, all presentations and following discussions were very active and fruitful. This report consists of total 35 papers including 13 oral and 22 poster presentations.

Proceedings of the 2017 Symposium on Nuclear Data; November 16-17, 2017, iVil, Tokai-mura, Ibaraki, Japan

Nishio, Katsuhisa; Utsuno, Yutaka; Chiba, Satoshi*; Koura, Hiroyuki; Iwamoto, Osamu; Nakamura, Shoji

JAEA-Conf 2018-001, 226 Pages, 2018/12

JAEA-Conf-2018-001.pdf:22.81MB

The 2017 Symposium on Nuclear Data was held at iVil in Tokai on November 16-17, 2017. The symposium was hosted by the Nuclear Data Division of the Atomic Energy Society of Japan (AESJ) and Advanced Science Research Center of Japan Atomic Energy Agency, and co-hosted by Japanese Nuclear Data Committee of AESJ and North Kanto Branch of AESJ. In the symposium, a tutorial was given by Prof. Rykaczewski (ORNL) "New nuclear data from total absorption spectroscopy and beta-delayed neutron measurements", as well as six oral sessions, "Nuclear Physics and Nuclear Data" (two sessions), "Nuclear Theory and Nuclear Data", "Reactors" and "Nuclear Data and Their Applications" (two sessions). In addition, recent advances in experiment, theory, evaluation, benchmark, and application were presented in the poster session. The symposium had 79 participants, who contributed to very active and fruitful discussions. This report consists of 37 papers, including those of 14 oral and 23 poster presentations.

Cutting-edge studies on nuclear data for continuous and emerging need, 3; Recent advancement of fission studies; Experimental and theoretical approaches

Nishio, Katsuhisa; Chiba, Satoshi*

Nihon Genshiryoku Gakkai-Shi ATOMO, 59(12), p.717 - 721, 2017/12

no abstracts in English