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experiment using a 
Cf calibration sourceLee, D. H.*; Dodo, Taku; Haga, Katsuhiro; Harada, Masahide; Hasegawa, Shoichi; Kasugai, Yoshimi; Kinoshita, Hidetaka; Masuda, Shiho; Meigo, Shinichiro; Sakai, Kenji; et al.
Nuclear Instruments and Methods in Physics Research A, 1072, p.170216_1 - 170216_6, 2025/03
Times Cited Count：2 Percentile：98.29(Instruments & Instrumentation)Dodo, Taku; Haga, Katsuhiro; Harada, Masahide; Hasegawa, Shoichi; Kasugai, Yoshimi; Kinoshita, Hidetaka; Masuda, Shiho; Meigo, Shinichiro; Sakai, Kenji; Suzuya, Kentaro; et al.
Progress of Theoretical and Experimental Physics (Internet), 2025(2), p.023H02_1 - 023H02_8, 2025/02
Times Cited Count：0 Percentile：0.00(Physics, Multidisciplinary)Marzec, E.*; Dodo, Taku; Haga, Katsuhiro; Harada, Masahide; Hasegawa, Shoichi; Kasugai, Yoshimi; Kinoshita, Hidetaka; Masuda, Shiho; Meigo, Shinichiro; Sakai, Kenji; et al.
Physical Review Letters, 134, p.081801_1 - 081801_9, 2025/00
Times Cited Count：1 Percentile：0.00(Physics, Multidisciplinary)Uno, Koichiro*; Okumura, Masahiko; Nakao, Atsushi*; Yamaguchi, Akiko; Yanai, Junta*
Science of the Total Environment, 949, p.175012_1 - 175012_8, 2024/11
Times Cited Count：0 Percentile：0.00(Environmental Sciences)Frayed edge sites (FES), formed by the partial weathering of mica minerals, selectively adsorb Cs ions. However, the detailed mechanism of this adsorption has not been fully clarified. In this study, cation extraction and Cs adsorption experiments were conducted on mica. It was found that potassium-adsorbed mica adsorbed more Cs than rubidium-adsorbed mica. To elucidate the cause of this, the stability of Cs, rubidium, and potassium adsorbed on FES was evaluated using first-principles calculations. It was determined that the presence of potassium as the cation species prior to Cs adsorption is important for the stability of Cs on the FES.
Meigo, Shinichiro; Yamaguchi, Yuji
Proceedings of 21st Annual Meeting of Particle Accelerator Society of Japan (Internet), p.853 - 858, 2024/10
no abstracts in English
Meigo, Shinichiro; Yamaguchi, Yuji; Iwamoto, Hiroki
Proceedings of 21st Annual Meeting of Particle Accelerator Society of Japan (Internet), p.32 - 37, 2024/10
no abstracts in English
Yamaguchi, Yuji; Meigo, Shinichiro; Yamazaki, Takayuki*
Proceedings of 21st Annual Meeting of Particle Accelerator Society of Japan (Internet), p.239 - 243, 2024/10
Fringe field of a secondary-particle capture solenoid magnet with three coils has been experimentally investigated placed at muon science facility in materials and life science experimental facility (MLF), J-PARC. To clarify relationship between the fringe field and excitation current of each coil and interference of fields by the coils, proton beam position changes in vertical direction were measured for 125(= 5
) combinations of excitation currents using a multi-wire profile monitor located in front of the final target of MLF. The measured position changes show that the field by the most upstream coil is non-linear with its current while the fields by other coils are linear and that the field can be enhanced by excitation of multiple coils. The non-linearity of the filed by the most upstream coil has been introduced to the proton beam orbit correction, which has been demonstrated.
experimentLee, D. H.*; Dodo, Taku; Haga, Katsuhiro; Harada, Masahide; Hasegawa, Shoichi; Kasugai, Yoshimi; Kinoshita, Hidetaka; Masuda, Shiho; Meigo, Shinichiro; Sakai, Kenji; et al.
European Physical Journal C, 84, p.409_1 - 409_6, 2024/04
Times Cited Count：1 Percentile：35.96(Physics, Particles & Fields)Moriyama, Junichiro*; Takakuwa, Osamu*; Yamaguchi, Masatake; Ogawa, Yuhei*; Tsuzaki, Kaneaki*
Computational Materials Science, 232, p.112650_1 - 112650_11, 2024/01
Times Cited Count：4 Percentile：39.92(Materials Science, Multidisciplinary)The present study focuses on a novel hydrogen-improved strength-ductility balance in some practical Fe-Cr-Ni-based austenitic alloys, which directly depends on the solute hydrogen content. The hydrogen absorption energy of the Fe-Cr-Ni model alloys with the face-centered cubic structure was examined using first-principles calculations to verify the contribution of Cr and Ni substitutions from Fe to the hydrogen solubility in the alloys. The Cr substitution substantially reduced the hydrogen absorption energy compared to the Ni substitution, whereby the increased Cr/Ni ratio exerts higher hydrogen solubility. The propensity in the calculations coincided with the experimental results obtained previously in the practical alloys with various Cr / Ni ratios.
-II neutrino targetShin, C. D.*; Dodo, Taku; Haga, Katsuhiro; Harada, Masahide; Hasegawa, Shoichi; Kasugai, Yoshimi; Kinoshita, Hidetaka; Masuda, Shiho; Meigo, Shinichiro; Sakai, Kenji; et al.
Journal of Instrumentation (Internet), 18(12), p.T12001_1 - T12001_9, 2023/12
Times Cited Count：0 Percentile：0.00(Instruments & Instrumentation)Takahashi, Tone; Yamaguchi, Ikuto*; Hironaka, Kota*; Mochimaru, Takanori*; Koizumi, Mitsuo; Yamanishi, Hirokuni*; Wakabayashi, Genichiro*
Dai-44-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 4 Pages, 2023/11
To enhance the counter capability against terrorism in major public events, the Japan Atomic Energy Agency (JAEA) has started developments of monitoring technique that covers wide-area and rapidly detects nuclear and radioactive materials. In this project, we are developing widely applicable radiation mapping device by combining with positioning sensors and a network device. Mapping tests inside and outside of the building by using the device to locate areas with high radiation count has been performed. Also, fast neutron detection technique using plastic scintillation detectors is being developed for detection of neutron sources including nuclear materials. Measurement with two rod shaped detector that placed into a cross showed better localizing capability compared with single detector. In this report, recent progresses of the project are given.
values calculated from radiocesium interception potentialUno, Koichiro*; Nakao, Atsushi*; Okumura, Masahiko; Yamaguchi, Akiko; Kogure, Toshihiro*; Yanai, Junta*
Nihon Dojo Hiryo Gaku Zasshi, 94(5), p.376 - 384, 2023/10
Radiocesium interception potential (RIP) has been widely used as a quantitative indicator of cesium (Cs) adsorption capacity of soil, but it has been found that RIP does not always correlate with the distribution coefficient () of Cs in the actual environment. In order to clarify the cause of this discrepancy, we measured Kd using more realistic solutions, compared it with RIP, and evaluated the mineral structure. As a result, it was found that the concentration of competing cations, such as potassium and ammonium ions, and the structural change of the mineral itself are important.
Toyoda, Shin*; Inoue, Kazuhiko*; Yamaguchi, Ichiro*; Hoshi, Masaharu*; Hirota, Seiko*; Oka, Toshitaka; Shimazaki, Tatsuya*; Mizuno, Hideyuki*; Tani, Atsushi*; Yasuda, Hiroshi*; et al.
Radiation Protection Dosimetry, 199(14), p.1557 - 1564, 2023/09
Times Cited Count：1 Percentile：23.64(Environmental Sciences)Interlaboratory comparison studies are important for radiation dosimetry in order to demonstrate how the technique is universally available. The set of standard samples are examined in each participating laboratory in the present study. After a set of standard samples together with the samples with unknown doses, which were prepared in the same laboratory as the standard samples, are measured at a participating laboratory, those samples are sent to another participating laboratory for next measurement. There is some small difference observed in the sensitivity (the slope of the dose response line) of the standard samples while the differences in the obtained doses for the samples with unknown doses are rather systematic, implying that the difference is mostly due to the samples but not to measurements.
muon spin relaxation method and first-principles calculationsTsuru, Tomohito; Nishimura, Katsuhiko*; Matsuda, Kenji*; Nunomura, Norio*; Namiki, Takahiro*; Lee, S.*; Higemoto, Wataru; Matsuzaki, Teiichiro*; Yamaguchi, Masatake; Ebihara, Kenichi; et al.
Metallurgical and Materials Transactions A, 54(6), p.2374 - 2383, 2023/06
Times Cited Count：2 Percentile：23.52(Materials Science, Multidisciplinary)Although hydrogen embrittlement susceptibility of high-strength Al alloys is recognized as a critical issue in the practical use of Al alloys, identifying the hydrogen trapping or distribution has been challenging. In the present study, an effective approach based on experiment and simulation is proposed to explore the potential trap sites in Al alloys. Zero-field muon spin relaxation experiments were carried out for Al-0.5%Mg, Al-0.2%Cu, Al-0.15%Ti, Al-0.011%Ti, Al-0.28%V, and Al-0.015%V (at.%) in the temperature range from 5 to 300 K. The temperature variations of the dipole field widths have revealed three peaks for Al-0.5%Mg, four peaks for Al-0.2%Cu, three peaks for Al-0.011%Ti and Al-0.015%V. Atomic configurations of the muon trapping sites corresponding to the observed 
peaks are well assigned using the first-principles calculations for the trap energies of hydrogen around a solute and solute-vacancy pair. The extracted linear relationship between the muon peak temperature and the trap energy enables us to explore the potential alloying elements and their complex that have strong binding energies with hydrogen in Al alloys.
Koizumi, Mitsuo; Takahashi, Tone; Hironaka, Kota; Mochimaru, Takanori*; Yamaguchi, Ikuto*; Kimura, Yoshiki; Tanigaki, Minoru*; Masaki, Hiroko*; Harada, Hiroshi*; Goto, Jun*; et al.
Proceedings of INMM & ESARDA Joint Annual Meeting 2023 (Internet), 7 Pages, 2023/05
Nii, Keisuke*; Ida, Yoshiaki*; Ueda, Hideki*; Yamaguchi, Takanori*; Kabumoto, Hiroshi; Kamiya, Junichiro; Kondo, Yasuhiro; Tamura, Jun; Harada, Hiroyuki; Matsui, Yutaka; et al.
Proceedings of 19th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.601 - 604, 2023/01
no abstracts in English
Meigo, Shinichiro; Yamaguchi, Yuji; Nakano, Keita*; Sugihara, Kenta*
Proceedings of 19th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.132 - 136, 2023/01
J-PARC accelerator facility is the only accelerator facility in Japan that can provide proton beams in the energy range of 400 MeV or higher. In the J-PARC accelerator facility, it is difficult to install users' experimental equipment inside the proton beam duct in order to maintain stable user operation. In addition, due to the characteristics of the synchrotron accelerator, it is not possible to supply a low-intensity beam enough to confirm the detector. In addition, it is important to improve the intranuclear cascade model (INCL) for high-intensity proton accelerator facilities such as accelerator-driven transmutation systems (ADS), etc. In order to improve the INCL, DDX of the forward-most emitted particles is important, but new data should be obtained since there are few experimental data available. In order to promote space utilization and to improve the accuracy of the INCL, energy spectra of scattered protons at the Al beam window placed at the inlet of the 3NBT dump were measured. In the experiment, plastic scintillators were used with 400 MeV proton beam. The results show that the spectra have sharp peaks due to elastic scattering. The calculation of the PHITS code using INCL reproduced the sharp peak due to elastic scattering well, although it overestimated the contribution of quasi-elastic scattering in the experimental data. In conclusion, it is clear that the present method can be used to utilize protons in several GeV regions for space exploration.
Yamaguchi, Yuji; Meigo, Shinichiro
JAEA-Conf 2022-001, 226 Pages, 2022/11
JAEA-Conf-2022-001.pdf:17.97MB
The 2021 Symposium on Nuclear Data was held as an online connection conference on November 18-19, 2021. The symposium was organized by the Nuclear Data Division of the Atomic Energy Society of Japan (AESJ) in cooperation with the Sigma Investigative Advisory Committee of AESJ, J-PARC Center, Nuclear Science and Engineering Center of Japan Atomic Energy Agency (JAEA), and High Energy Accelerator Research Organization (KEK). In the symposium, tutorials "New Developments in TALYS and TENDL-2021" and "Role of ADS and its Development Issues" were proposed and held. Three sessions of lectures and discussions were held: "J-PARC and JAEA Facilities", "Current Status and Future Prospects of Nuclear Data Research", and "Medical, Isotope Production, and Analysis". 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 132 participants. Each oral and poster presentation was followed by an active question and answer session. This report consists of a total of 36 papers including 14 oral and 22 poster presentations.
Igarashi, Yu; Yamaguchi, Ichiro*; Oda, Keiji*; Fukushi, Masahiro*; Sakama, Minoru*; Iimoto, Takeshi*
Nihon Hoshasen Anzen Kanri Gakkai-Shi, 21(2), p.74 - 76, 2022/11
no abstracts in English
Katayama, Ryo*; Kako, Eiji*; Yamaguchi, Seiya*; Michizono, Shinichiro*; Umemori, Kensei*; Kondo, Yasuhiro
Physical Review Accelerators and Beams (Internet), 25(2), p.021601_1 - 021601_18, 2022/02
Times Cited Count：4 Percentile：43.00(Physics, Nuclear)We investigated the feasibility on the application of a superconducting radio frequency (SRF) niobium cavity to an accelerator-based neutron source for boron neutron capture therapy (BNCT). This paper presents a first feasibility study on the application of a SRF niobium cavity to an accelerator-based neutron source for BNCT, assuming that a superconducting radio frequency quadrupole (SC-RFQ) composed of pure bulk niobium at 4.2 K accelerates the proton/deuteron beams to a beryllium or lithium target for the neutron production of BNCT. We evaluated the feasibility on the following three criteria: comparison of the cooling capacity of the refrigerator to the amount of heat, power consumption of AC, and size of the BNCT system. This study demonstrated that the application of the SRF cavity for the rf-linac-based neutron source of BNCT is feasible, and the 2.5 MeV deuteron SC-RFQ and lithium target system is the optimum.
