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Journal Articles

Application of ESR thermochronology for mountains in Japan; An Assessment of ESR signal variation caused by sample preparation

Kajita, Yuya*; Sueoka, Shigeru; Tani, Atsushi*; Isotani, Shusuke*; Tagami, Takahiro*

Fisshion, Torakku Nyusureta, (36), p.6 - 8, 2023/12

no abstracts in English

Journal Articles

Impact of the ground-state 4${it f}$ symmetry for anisotropic ${it cf}$ hybridization in the heavy-fermion superconductor CeNi$$_{2}$$Ge$$_{2}$$

Fujiwara, Hidenori*; Nakatani, Yasuhiro*; Aratani, Hidekazu*; Kanai, Yuina*; Yamagami, Kohei*; Hamamoto, Satoru*; Kiss, Takayuki*; Yamasaki, Atsushi*; Higashiya, Atsushi*; Imada, Shin*; et al.

Physical Review B, 108(16), p.165121_1 - 165121_10, 2023/10

 Times Cited Count:0 Percentile:0(Materials Science, Multidisciplinary)

Journal Articles

Interlaboratory comparison of electron paramagnetic resonance tooth enamel dosimetry with investigations of the dose responses of the standard samples

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:0 Percentile:0.01(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.

Journal Articles

Angular distribution of $$gamma$$ rays from a neutron-induced $$p$$-wave resonance of $$^{132}$$Xe

Okudaira, Takuya*; Tani, Yuika*; Endo, Shunsuke; Doskow, J.*; Fujioka, Hiroyuki*; Hirota, Katsuya*; Kameda, Kento*; Kimura, Atsushi; Kitaguchi, Masaaki*; Luxnat, M.*; et al.

Physical Review C, 107(5), p.054602_1 - 054602_7, 2023/05

 Times Cited Count:1 Percentile:68.16(Physics, Nuclear)

no abstracts in English

Journal Articles

Neutron/$$gamma$$-ray discrimination based on the property and thickness controls of scintillators using Li glass and LiCAF(Ce) in a $$gamma$$-ray field

Kaburagi, Masaaki; Shimazoe, Kenji*; Terasaka, Yuta; Tomita, Hideki*; Yoshihashi, Sachiko*; Yamazaki, Atsushi*; Uritani, Akira*; Takahashi, Hiroyuki*

Nuclear Instruments and Methods in Physics Research A, 1046, p.167636_1 - 167636_8, 2023/01

 Times Cited Count:3 Percentile:90.12(Instruments & Instrumentation)

We focus on the thickness and property controls of inorganic scintillators used for thermal neutron detection in intense $$gamma$$-ray fields without considering pulse shape discrimination techniques. GS20$$^{rm{TM}}$$ (a lithium glass) and LiCaAlF$$_6$$:Ce(LiCAF:Ce) cintillators with thicknesses of 0.5 and 1.0 mm, respectively, have been employed. Pulse signals generated by photomultiplier tubes, to which the scintillators were coupled, were inserted into a digital pulse processing unit with 1 Gsps, and the areas of waveforms were integrated for 360 ns. In a $$^{60}$$Co $$gamma$$-ray field, the neutron detection for GS20$$^{rm{TM}}$$ with a 0.5-mm thickness was possible at dose rates of up to 0.919 Gy/h; however, for LiCAF:Ce, neutron detection was possible at 0.473 Gy/h, and it failed at 0.709 Gy/h. Threfore, in a $$^{60}$$Co $$gamma$$-ray field, the neutron/$$gamma$$-ray discrimination of GS20$$^{rm{TM}}$$ was better than that of LiCAF:Ce due to its better energy resolution and higher detection efficiency.

Journal Articles

Efficient hydrogen isotope separation by tunneling effect using graphene-based heterogeneous electrocatalysts in electrochemical hydrogen isotope pumping

Yasuda, Satoshi; Matsushima, Hisayoshi*; Harada, Kenji*; Tanii, Risako*; Terasawa, Tomoo; Yano, Masahiro; Asaoka, Hidehito; Gueriba, J. S.*; Di$~n$o, W. A.*; Fukutani, Katsuyuki

ACS Nano, 16(9), p.14362 - 14369, 2022/09

 Times Cited Count:12 Percentile:85.62(Chemistry, Multidisciplinary)

The fabrication of hydrogen isotope enrichment system is essential for the development of industrial, medical, life science, and nuclear fusion fields, therefore alternative enrichment techniques with high separation factor and economic feasibility have been still explored. Herein, we report the fabrication of heterogeneous electrode with layered structures consisting of palladium and graphene layers for polymer electrolyte membrane electrochemical hydrogen pumping for the hydrogen isotope enrichment. We demonstrated significant bias voltage dependence of hydrogen/deuterium (H/D) separation ability and its high H/D at lower bias voltage. Theoretical analysis also demonstrated that the observed high H/D at low bias voltage stems from hydrogen isotopes tunneling through atomically-thick graphene during the electrochemical reaction, and the bias dependent H/D results in a transition from the quantum tunneling regime to classical over- barrier regime for hydrogen isotopes transfer via the graphene. These findings provide new insight for a novel economical methodology of efficient hydrogen isotope enrichment.

Journal Articles

Design and actual performance of J-PARC 3 GeV rapid cycling synchrotron for high-intensity operation

Yamamoto, Kazami; Kinsho, Michikazu; Hayashi, Naoki; Saha, P. K.; Tamura, Fumihiko; Yamamoto, Masanobu; Tani, Norio; Takayanagi, Tomohiro; Kamiya, Junichiro; Shobuda, Yoshihiro; et al.

Journal of Nuclear Science and Technology, 59(9), p.1174 - 1205, 2022/09

 Times Cited Count:6 Percentile:84.97(Nuclear Science & Technology)

In the Japan Proton Accelerator Research Complex, the purpose of the 3 GeV rapid cycling synchrotron (RCS) is to accelerate a 1 MW, high-intensity proton beam. To achieve beam operation at a repetition rate of 25 Hz at high intensities, the RCS was elaborately designed. After starting the RCS operation, we carefully verified the validity of its design and made certain improvements to establish a reliable operation at higher power as possible. Consequently, we demonstrated beam operation at a high power, namely, 1 MW. We then summarized the design, actual performance, and improvements of the RCS to achieve a 1 MW beam.

Journal Articles

Hybrid process combining solvent extraction / low pressure loss extraction chromatography for a reasonable MA(III) recovery process

Sano, Yuichi; Sakamoto, Atsushi; Miyazaki, Yasunori; Watanabe, So; Morita, Keisuke; Emori, Tatsuya; Ban, Yasutoshi; Arai, Tsuyoshi*; Nakatani, Kiyoharu*; Matsuura, Haruaki*; et al.

Proceedings of International Conference on Nuclear Fuel Cycle; Sustainable Energy Beyond the Pandemic (GLOBAL 2022) (Internet), 4 Pages, 2022/07

We developed a hybrid MA(III) recovery process combining MA(III)+Ln(III) co-recovery flowsheet by solvent extraction with TBP and MA(III)/Ln(III) separation flowsheet by simulated moving bed chromatography using HONTA impregnated adsorbents with large particle size porous silica support.

Journal Articles

Angular distribution of $$gamma$$ rays from the $$p$$-wave resonance of $$^{118}$$Sn

Koga, Jun*; Takada, Shusuke*; Endo, Shunsuke; Fujioka, Hiroyuki*; Hirota, Katsuya*; Ishizaki, Kohei*; Kimura, Atsushi; Kitaguchi, Masaaki*; Niinomi, Yudai*; Okudaira, Takuya*; et al.

Physical Review C, 105(5), p.054615_1 - 054615_5, 2022/05

 Times Cited Count:3 Percentile:66.85(Physics, Nuclear)

no abstracts in English

Journal Articles

Approach to elucidate corrosion mechanism on metal surface using first-principles calculations

Igarashi, Takahiro; Otani, Kyohei; Komatsu, Atsushi; Kato, Chiaki; Sakairi, Masatoshi*

Bosei Kanri, 66(4), p.141 - 145, 2022/04

Metal corrosion is a material deterioration phenomenon based on electrochemical reactions on an atomic scale. In this paper, various methods for acquiring physical properties on metal surfaces using first-principles calculations were described. As examples of applying first-principles calculation to metal corrosion, the effect of hydrogen adsorption on the metal surface on the potential change and the effect of cation atoms in the aqueous solution on the corrosion resistance of the metal were reported.

Journal Articles

Feasibility study of the one-dimensional radiation distribution sensing method using an optical fiber sensor based on wavelength spectrum unfolding

Terasaka, Yuta; Watanabe, Kenichi*; Uritani, Akira*; Yamazaki, Atsushi*; Sato, Yuki; Torii, Tatsuo; Wakaida, Ikuo

Journal of Nuclear Engineering and Radiation Science, 7(4), p.042002_1 - 042002_7, 2021/10

For the application in the measurement of the high dose rate hot spots inside the Fukushima Daiichi Nuclear Power Station (FDNPS) buildings, we propose a novel one-dimensional radiation distribution sensing method using an optical fiber sensor based on wavelength spectrum unfolding. The proposed method estimates the incident position of radiation to the fiber by the unfolding of the wavelength spectrum output from the fiber edge using the fact that the attenuation length of light along the fiber depends on the wavelength. Because this method measures the integrated light intensity, this method can avoid the problem of counting loss and signal pile-up, which occurs in the radiation detector with pulse counting mode under high dose rate field. Through basic experiments using the ultraviolet light source and $$^{90}$$Sr/$$^{90}$$Y radioactive point source, basic properties of source position detection were confirmed.

Journal Articles

Energy-dependent angular distribution of individual $$gamma$$ rays in the $$^{139}$$La($$n, gamma$$)$$^{140}$$La$$^{ast}$$ reaction

Okudaira, Takuya*; Endo, Shunsuke; Fujioka, Hiroyuki*; Hirota, Katsuya*; Ishizaki, Kohei*; Kimura, Atsushi; Kitaguchi, Masaaki*; Koga, Jun*; Niinomi, Yudai*; Sakai, Kenji; et al.

Physical Review C, 104(1), p.014601_1 - 014601_6, 2021/07

 Times Cited Count:4 Percentile:57.13(Physics, Nuclear)

Journal Articles

Spin excitations of the $$S$$=1/2 one-dimensional Ising-like antiferromagnet BaCo$$_{2}$$V$$_{2}$$O$$_{8}$$ in transverse magnetic fields

Okutani, Akira*; Onishi, Hiroaki; Kimura, Shojiro*; Takeuchi, Tetsuya*; Kida, Takanori*; Mori, Michiyasu; Miyake, Atsushi*; Tokunaga, Masashi*; Kindo, Koichi*; Hagiwara, Masayuki*

Journal of the Physical Society of Japan, 90(4), p.044704_1 - 044704_9, 2021/04

 Times Cited Count:3 Percentile:30.35(Physics, Multidisciplinary)

Journal Articles

Thermally altered subsurface material of asteroid (162173) Ryugu

Kitazato, Kohei*; Milliken, R. E.*; Iwata, Takahiro*; Abe, Masanao*; Otake, Makiko*; Matsuura, Shuji*; Takagi, Yasuhiko*; Nakamura, Tomoki*; Hiroi, Takahiro*; Matsuoka, Moe*; et al.

Nature Astronomy (Internet), 5(3), p.246 - 250, 2021/03

 Times Cited Count:43 Percentile:96.93(Astronomy & Astrophysics)

Here we report observations of Ryugu's subsurface material by the Near-Infrared Spectrometer (NIRS3) on the Hayabusa2 spacecraft. Reflectance spectra of excavated material exhibit a hydroxyl (OH) absorption feature that is slightly stronger and peak-shifted compared with that observed for the surface, indicating that space weathering and/or radiative heating have caused subtle spectral changes in the uppermost surface. However, the strength and shape of the OH feature still suggests that the subsurface material experienced heating above 300 $$^{circ}$$C, similar to the surface. In contrast, thermophysical modeling indicates that radiative heating does not increase the temperature above 200 $$^{circ}$$C at the estimated excavation depth of 1 m, even if the semimajor axis is reduced to 0.344 au. This supports the hypothesis that primary thermal alteration occurred due to radiogenic and/or impact heating on Ryugu's parent body.

Journal Articles

High-spin states in $$^{35}$$S

Go, Shintaro*; Ideguchi, Eiji*; Yokoyama, Rin*; Aoi, Nori*; Azaiez, F.*; Furutaka, Kazuyoshi; Hatsukawa, Yuichi; Kimura, Atsushi; Kisamori, Keiichi*; Kobayashi, Motoki*; et al.

Physical Review C, 103(3), p.034327_1 - 034327_8, 2021/03

 Times Cited Count:4 Percentile:57.13(Physics, Nuclear)

Journal Articles

Measurement of cesium isotopic ratio by thermal ionization mass spectrometry for neutron capture reaction studies on $$^{135}$$Cs

Shibahara, Yuji*; Nakamura, Shoji; Uehara, Akihiro*; Fujii, Toshiyuki*; Fukutani, Satoshi*; Kimura, Atsushi; Iwamoto, Osamu

Journal of Radioanalytical and Nuclear Chemistry, 325(1), p.155 - 165, 2020/07

 Times Cited Count:8 Percentile:71.58(Chemistry, Analytical)

The measurements of isotopic ratios of Cs samples by thermal ionization mass spectrometry were performed for the analysis of their samples used to evaluate nuclear data obtained for $$^{135}$$Cs. To obtain a high intensity and stable ion beam, the effects of additive agents on the ionization of Cs were examined. The effect of silicotungstic acid on the ionization of Cs was the largest among the additive agents studied in the present study, while the silicotungstic acid also showed the largest isobaric interference of polyatomic ions. It was demonstrated that as small as 2$$times$$10$$^{-13}$$ g of a Cs sample was sufficient to achieve the analytical precision required to measure the $$^{135}$$Cs/$$^{137}$$Cs ratio in the case where an additive agent of TaO/glucose was employed. After examining of the analytical conditions, such as the interference effect due to Ba, the measurements of the isotopic ratios of two Cs samples used in our study using TIMS were conducted, and it was discussed how much the ratios contributed to evaluation of the neutron capture cross-section of $$^{135}$$Cs.

Journal Articles

Transverse asymmetry of $$gamma$$ rays from neutron-induced compound states of $$^{140}$$La

Yamamoto, Tomoki*; Okudaira, Takuya; Endo, Shunsuke; Fujioka, Hiroyuki*; Hirota, Katsuya*; Ino, Takashi*; Ishizaki, Kohei*; Kimura, Atsushi; Kitaguchi, Masaaki*; Koga, Jun*; et al.

Physical Review C, 101(6), p.064624_1 - 064624_8, 2020/06

 Times Cited Count:9 Percentile:73.66(Physics, Nuclear)

JAEA Reports

Tritium removal of heavy water system and helium system in FUGEN

Takiya, Hiroaki; Kadowaki, Haruhiko; Matsushima, Akira; Matsuo, Hidehiko; Ishiyama, Masahiro; Aratani, Kenta; Tezuka, Masashi

JAEA-Technology 2020-001, 76 Pages, 2020/05

JAEA-Technology-2020-001.pdf:6.06MB

Advanced Thermal Reactor (ATR) FUGEN was operated for about 25 years, and now has been proceeding decommissioning after the approval of the decommissioning plan in Feb. 2008. The reactor, heavy water system and helium system are contaminated by tritium because of neutron absorption of heavy water, which is a moderator. Before dismantling these facilities, it is necessary to remove tritium from them for not only reducing the amount of tritium released to surrounding environment and the risk of internal exposure by tritium but also ensuring the workability. In first phase of decommissioning (Heavy Water and Other system Decontamination Period), tritium decontamination of the reactor, heavy water system and helium system started in 2008 and completed in 2018. This report shows the results of tritium decontamination of the reactor, heavy water system and helium system.

Journal Articles

Development of event-type neutron imaging detectors at the energy-resolved neutron imaging system RADEN at J-PARC

Parker, J. D.*; Harada, Masahide; Hayashida, Hirotoshi*; Hiroi, Kosuke; Kai, Tetsuya; Matsumoto, Yoshihiro*; Nakatani, Takeshi; Oikawa, Kenichi; Segawa, Mariko; Shinohara, Takenao; et al.

Materials Research Proceedings, Vol.15, p.102 - 107, 2020/05

Journal Articles

Development of one-dimensional optical fiber type radiation distribution sensing method based on wavelength spectrum unfolding

Terasaka, Yuta; Watanabe, Kenichi*; Uritani, Akira*; Yamazaki, Atsushi*; Sato, Yuki; Torii, Tatsuo; Wakaida, Ikuo

Proceedings of International Youth Nuclear Congress 2020 (IYNC 2020) (Internet), 4 Pages, 2020/05

274 (Records 1-20 displayed on this page)