Benchmarks of iron nuclear data for fusion neutron sources

Kwon, Saerom*; Konno, Chikara; Honda, Shogo*; Kenjo, Shunsuke*; Sato, Satoshi*

Fusion Engineering and Design, 223, p.115548_1 - 115548_8, 2026/02

https://doi.org/10.1016/j.fusengdes.2025.115548

In order to evaluate the accuracy of the iron data in the latest nuclear data libraries (FENDL-3.2b, JENDL-5, ENDF/B-VIII.0 and JEFF-3.3) used in the fusion neutron source design, we performed their benchmark tests by using QST/TIARA iron experiment with quasi mono-energy neutrons of 40 and 65 MeV and JAEA/FNS iron experiment with DT neutrons. From the test results, we have found the following issues; (1) The calculation results with FENDL-3.2b underestimate the measured neutron fluxes of the continuous energy range (10-60 MeV) by a factor of 0.6 in the TIARA experiment with 65 MeV neutrons; (2) The calculation results with FENDL-3.2b tend to underestimate the measured neutron flux above 10 MeV by a factor of 0.8 at depth of 70 cm and overestimate the measured ones below 10 keV by a factor of 1.3 up to depth of 40 cm in the FNS experiment. We investigated those issues in detail and clarified their reasons.

sp. nov., a novel hydrogen-producing bacterium isolated from a deep diatomaceous shale formation

Ueno, Akio*; Sato, Kiyoshi*; Tamamura, Shuji*; Murakami, Takuma*; Inomata, Hidenori*; Tamazawa, Satoshi*; Amano, Yuki; Miyakawa, Kazuya; Naganuma, Takeshi*; Igarashi, Toshifumi*

International Journal of Systematic and Evolutionary Microbiology, 75(6), p.006802_1 - 006802_11, 2025/06

https://doi.org/10.1099/ijsem.0.006802

no abstracts in English

Annual report on the environmental radiation monitoring around the Tokai Reprocessing Plant FY2023

Kokubun, Yuji; Hosomi, Kenji; Nagaoka, Mika; Seya, Natsumi; Inoue, Kazumi; Koike, Yuko; Uchiyama, Rei; Sasaki, Kazuki; Maehara, Yushi; Matsuo, Kazuki; et al.

JAEA-Review 2024-054, 168 Pages, 2025/03

JAEA-Review-2024-054.pdf:2.73MB

The Nuclear Fuel Cycle Engineering Laboratories conducts environmental radiation monitoring around the reprocessing plant in accordance with the "Safety Regulations for Reprocessing Plant of JAEA, Part IV: Environmental Monitoring". This report summarizes the results of environmental radiation monitoring conducted during the period from April 2023 to March 2024 and the results of dose calculations for the surrounding public due to the release of radioactive materials from the plant into the atmosphere and ocean. In the results of the above environmental radiation monitoring, several items were affected by radioactive materials emitted from the accident at the Fukushima Daiichi Nuclear Power Station of Tokyo Electric Power Company, Incorporated (changed to Tokyo Electric Power Holdings, Inc. on April 1, 2016), which occurred in March 2011. In addition, environmental monitoring plan, analysis and measurement methods, monitoring data and their chronological change, meteorological data after statistical processing, status of radioactive waste release and evaluation results of the data over the normal range are included as appendices.

Optimization of microwave power in ESR dosimetry of tooth enamel in Japanese macaques

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

International Journal of Radiation Biology, 8 Pages, 2025/00

https://doi.org/10.1080/09553002.2025.2534998

no abstracts in English

Assessment of individual external exposure doses based on environmental radiation in areas affected by the Fukushima Daiichi Nuclear Power Station accident

Sato, Rina; Yoshimura, Kazuya; Sanada, Yukihisa; Mikami, Satoshi; Yamada, Tsutomu*; Nakasone, Takamasa*; Kanaizuka, Seiichi*; Sato, Tetsuro*; Mori, Tsubasa*; Takagi, Marie*

Environment International, 194, p.109148_1 - 109148_8, 2024/12

https://doi.org/10.1016/j.envint.2024.109148

Assessment of individual external doses from ambient dose equivalents is used for predictive and retrospective assessments where personal dosimeters are not applicable. However, it tends to contain more errors than assessment by personal dosimetry due to various parameters. Therefore, in order to accurately assess the individual dose from ambient dose equivalents, a model that estimates effective doses considering life patterns and the shielding effects by buildings and vehicles, were developed in this study. The model parameters were examined using robust datasets of environmental radiation measured in the areas affected by the Fukushima Daiichi Nuclear Power Station accident in 2020 to 2021. The accuracy of the model was validated by comparison with 106 daily personal doses measured in Fukushima Prefecture in 2020. The measured personal dose was well reproduced by the model-estimated effective dose, showing that the model can be used to assess the individual exposure dose, similar to personal dosimetry. Furthermore, this model is an effective tool for radiation protection, as it can estimate the individual dose predictively and retrospectively by using environmental radiation data.

Study on microwave power dependency of electron spin resonance spectrum of carbonate radicals in teeth

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

KEK Proceedings 2024-6, p.91 - 95, 2024/12

We aim to improve the detection limit of the ESR dosimetry method. In this study, the saturation behavior of each radical was investigated by varying the microwave power during ESR measurement. Based on the difference in spin relaxation time between carbonate radicals and native radicals, it is expected that the signal-to-noise ratio improves and the detection limit can be lowered when the microwave power is increased to 4.0 mW.

Complete genome sequence of sp. strain V2501 isolated from 250 m below the ground level in Horonobe, Hokkaido, Japan

Ueno, Akio*; Sato, Kiyoshi*; Tamamura, Shuji*; Murakami, Takuma*; Inomata, Hidenori*; Tamazawa, Satoshi*; Amano, Yuki; Miyakawa, Kazuya; Naganuma, Takeshi*; Igarashi, Toshifumi*

Microbiology Resource Announcements (Internet), 13(11), p.e00108-24_1 - e00108-24_4, 2024/11

https://doi.org/10.1128/mra.00108-24

Characteristics of smartphone-wirelessly-connected personal dosemeters

Mikami, Satoshi; Tokiyoshi, Masanori*; Sato, Rina*; Tanaka, Daisuke*; Yoshimura, Kazuya

Nihon Hoshasen Anzen Kanri Gakkai-Shi, 23(1), p.10 - 17, 2024/06

https://doi.org/10.11269/jjrsm.23.10

Taisei Corporation and Infocube LAFLA Co., Ltd. have developed the smartphone-wirelessly-connected dosemeters, aiming to apply it to real-time exposure management of multiple decontamination workers. In order to grasp the basic characteristics of the developed dosemeters, they were calibrated and tested their characteristics such as energy dependency, angle of incidence dependency, etc. at photon calibration fields in Japan Atomic Energy Agency. The results showed generally good characteristics in each test. We evaluated that the dosemeters can be effectively used for decontamination work.

Microbiome analysis of the restricted bacteria in radioactive element-containing water at the Fukushima Daiichi Nuclear Power Station

Warashina, Tomoro*; Sato, Asako*; Hinai, Hiroshi; Shaikhutdinov, N.*; Shagimardanova, E.*; Mori, Hiroshi*; Tamaki, Satoshi*; Saito, Motofumi*; Sanada, Yukihisa; Sasaki, Yoshito; et al.

Applied and Environmental Microbiology, 90(4), p.e02113-23_1 - e02113-23_23, 2024/04

https://doi.org/10.1128/aem.02113-23

Development of contamination detection system combined with various remote devices

Morishita, Yuki; Miyamura, Hiroko; Sato, Yuki; Oura, Masatoshi*

Radiation Measurements, 171, p.107064_1 - 107064_7, 2024/02

https://doi.org/10.1016/j.radmeas.2024.107064

The detection of alpha and beta contamination locations is important for decontaminating nuclear facilities. In the high radiation dose rate environment at the decommissioning sites, the contamination measurement by the workers is not effective. Thus, we developed a remote automatic contamination measurement system using a new scintillator-based detector. A 50 mm 100-m-thick YAlO(Ce)(YAP:Ce) scintillator was coupled with a flat panel-type multianode photomultiplier tube. The detector was installed downwards at the bottom of a robot. It has an energy measurement capability, and the energy measurement could discriminate the alpha particles from the beta and Rn alpha particles. With the energy information, alpha and beta particles could be identified and mapped simultaneously. In addition, a slow-moving robot could be used to obtain statistically sufficient counts in a single run measurement, allowing the evaluation of surface contamination density using only alpha particles. The remote automatic contamination measurement system will be useful in visualizing the contamination distribution in environments that are inaccessible to workers.