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Vu, TheDang*; Shishido, Hiroaki*; Aizawa, Kazuya; Oku, Takayuki; Oikawa, Kenichi; Harada, Masahide; Kojima, Kenji M*; Miyajima, Shigeyuki*; Soyama, Kazuhiko; Koyama, Tomio*; et al.
IEEJ Transactions on Electrical and Electronic Engineering, 19(11), p.1888 - 1894, 2024/11
Times Cited Count:0 Percentile:0.00(Engineering, Electrical & Electronic)Oikawa, Kenichi; Matsumoto, Yoshihiro*; Watanabe, Kenichi*; Sato, Hirotaka*; Parker, J. D.*; Shinohara, Takenao; Kiyanagi, Yoshiaki*
Scientific Reports (Internet), 14, p.27990_1 - 27990_11, 2024/11
Times Cited Count:0 Percentile:0.00(Multidisciplinary Sciences)Matsumoto, Yoshihiro*; Oikawa, Kenichi; Watanabe, Kenichi*; Sato, Hirotaka*; Parker, J. D.*; Shinohara, Takenao; Kiyanagi, Yoshiaki*
Journal of Archaeological Science; Reports, 58, p.104729_1 - 104729_10, 2024/10
Vu, TheDang*; Shishido, Hiroaki*; Aizawa, Kazuya; Oku, Takayuki; Oikawa, Kenichi; Harada, Masahide; Kojima, Kenji M*; Miyajima, Shigeyuki*; Soyama, Kazuhiko; Koyama, Tomio*; et al.
Journal of Physics; Conference Series, 2776, p.012009_1 - 012009_9, 2024/06
Ishida, Takekazu*; Vu, TheDang*; Shishido, Hiroaki*; Aizawa, Kazuya; Oku, Takayuki; Oikawa, Kenichi; Harada, Masahide; Kojima, Kenji M*; Miyajima, Shigeyuki*; Koyama, Tomio*; et al.
Journal of Low Temperature Physics, 214(3-4), p.152 - 157, 2024/02
Times Cited Count:0 Percentile:0.00(Physics, Applied)Oikawa, Kenichi; Sato, Hirotaka*; Watanabe, Kenichi*; Su, Y. H.; Shinohara, Takenao; Kai, Tetsuya; Kiyanagi, Yoshiaki*; Hasemi, Hiroyuki
Journal of Physics; Conference Series, 2605, p.012013_1 - 012013_6, 2023/10
Tsuchikawa, Yusuke; Kai, Tetsuya; Abe, Yuta; Oikawa, Kenichi; Parker, J. D.*; Shinohara, Takenao; Sato, Ikken
Journal of Physics; Conference Series, 2605, p.012022_1 - 012022_6, 2023/10
We developed a method to obtain the areal density distribution of boron, which has a large neutron cross section, by means of an energy resolved neutron imaging. Commonly in a measurement of elements with very high neutron sensitivity, the quantitative measurement becomes more difficult with the amount of element due to the neutron self-shielding effect. To avoid this effect, an energy-resolved method using known cross section data was attempted, and a quantitative imaging of such elements was demonstrated at the MLF of J-PARC. This presentation introduces a measurement of melted simulated-fuel assemblies obtained in the research of the Fukushima Daiichi Nuclear Power Plant after the severe accident. Energy-dependent neutron transmission rates of the samples were measured by a neutron imaging detector, and were analyzed to obtained the areal density of boron at each position.
Su, Y. H.; Oikawa, Kenichi; Shinohara, Takenao; Kai, Tetsuya; Horino, Takashi*; Idohara, Osamu*; Misaka, Yoshitaka*; Tomota, Yo*
International Journal of Fatigue, 174, p.107729_1 - 107729_12, 2023/09
Times Cited Count:10 Percentile:90.11(Engineering, Mechanical)Shishido, Hiroaki*; Vu, TheDang*; Aizawa, Kazuya; Kojima, Kenji M*; Koyama, Tomio*; Oikawa, Kenichi; Harada, Masahide; Oku, Takayuki; Soyama, Kazuhiko; Miyajima, Shigeyuki*; et al.
Journal of Applied Crystallography, 56(4), p.1108 - 1113, 2023/08
Times Cited Count:2 Percentile:32.63(Chemistry, Multidisciplinary)Ito, Daisuke*; Sato, Hirotaka*; Odaira, Naoya*; Saito, Yasushi*; Parker, J. D.*; Shinohara, Takenao; Kai, Tetsuya; Oikawa, Kenichi
Journal of Nuclear Materials, 569, p.153921_1 - 153921_6, 2022/10
Times Cited Count:3 Percentile:50.01(Materials Science, Multidisciplinary)Malamud, F.*; Santisteban, J. R.*; Gao, Y.*; Shinohara, Takenao; Oikawa, Kenichi; Tremsin, A.*
Journal of Applied Crystallography, 55(2), p.228 - 239, 2022/04
Times Cited Count:1 Percentile:19.15(Chemistry, Multidisciplinary)Hayashi, Koichi*; Lederer, M.*; Fukumoto, Yohei*; Goto, Masashi*; Yamamoto, Yuta*; Happo, Naohisa*; Harada, Masahide; Inamura, Yasuhiro; Oikawa, Kenichi; Oyama, Kenji*; et al.
Applied Physics Letters, 120(13), p.132101_1 - 132101_6, 2022/03
Times Cited Count:3 Percentile:20.28(Physics, Applied)Shishido, Hiroaki*; Nishimura, Kazuma*; Vu, TheDang*; Aizawa, Kazuya; Kojima, Kenji M*; Koyama, Tomio*; Oikawa, Kenichi; Harada, Masahide; Oku, Takayuki; Soyama, Kazuhiko; et al.
IEEE Transactions on Applied Superconductivity, 31(9), p.2400505_1 - 2400505_5, 2021/12
Times Cited Count:0 Percentile:0.00(Engineering, Electrical & Electronic)In this study, we employed a superconducting detector, current-biased kinetic-inductance detector (CB-KID) for neutron imaging using a pulsed neutron source. We employed the delay-line method, and high spatial resolution imaging with only four reading channels was achieved. We also performed wavelength-resolved neutron imaging by the time-of-flight method. We obtained the neutron transmission images of a Gd-Al alloy sample, inside which single crystals of GdAl were grown, using the delay-line CB-KID. Single crystals were well imaged, in both shapes and distributions, throughout the Al-Gd alloy. We identified Gd nuclei via neutron transmissions that exhibited characteristic suppression above the neutron wavelength of 0.03 nm. In addition, the Gd resonance dip, a dip structure of the transmission caused by the nuclear reaction between an isotope and neutrons, was observed even when the number of events was summed over a limited area of 15 m 12 m. Gd selective imaging was performed using the resonance dip of Gd, and it showed clear Gd distribution even with a limited neutron wavelength range of 1 pm.
Tremsin, A. S.*; Gao, Y.*; Makinde, A.*; Bilheux, H. Z.*; Bilheux, J. C.*; An, K.*; Shinohara, Takenao; Oikawa, Kenichi
Additive Manufacturing, 46, p.102130_1 - 102130_20, 2021/10
Times Cited Count:12 Percentile:54.19(Engineering, Manufacturing)Tremsin, A. S.*; Bilheux, H. Z.*; Bilheux, J. C.*; Shinohara, Takenao; Oikawa, Kenichi; Gao, Y.*
Nuclear Instruments and Methods in Physics Research A, 1009, p.165493_1 - 165493_12, 2021/09
Times Cited Count:4 Percentile:48.14(Instruments & Instrumentation)Vu, TheDang; Shishido, Hiroaki*; Aizawa, Kazuya; Kojima, Kenji M*; Koyama, Tomio*; Oikawa, Kenichi; Harada, Masahide; Oku, Takayuki; Soyama, Kazuhiko; Miyajima, Shigeyuki*; et al.
Nuclear Instruments and Methods in Physics Research A, 1006, p.165411_1 - 165411_8, 2021/08
Times Cited Count:1 Percentile:15.03(Instruments & Instrumentation)Harada, Masahide; Teshigawara, Makoto; Oi, Motoki; Oikawa, Kenichi; Takada, Hiroshi; Ikeda, Yujiro
Nuclear Instruments and Methods in Physics Research A, 1000, p.165252_1 - 165252_8, 2021/06
Times Cited Count:3 Percentile:39.03(Instruments & Instrumentation)This study explores high-energy neutron components of the extracted neutron beam at J-PARC pulsed neutron source using the foil activation method with threshold reactions. Foils of aluminum, gold, bismuth, niobium, and thulium were used to cover the neutron energy range from 0.3 MeV to 79.4 MeV. The experiment was performed using neutron beams of BL10 (NOBORU). The foils were irradiated by a neutron beam at 13.4 m from the moderator. To characterize high-energy neutron fields for irradiation applications, reaction rates in three different configurations with and without BC slit and Pb filter were examined. To compare the experiments with calculations given for the user, reaction rates for corresponding reactions were calculated by the PHITS code with the JENDL-3.2 and the JENDL dosimetry file. Although there was a systematic tendency in C/E (Calculation/Experiment) ratios for different threshold energies, which C/E ratio decreased as threshold energy increased up to 100 MeV, and all C/E ratios were in the range of 1.00.2. This indicated that high-energy neutron calculations were adequate for the analysis of experimental data for NOBORU users.
Saito, Wataru*; Hayashi, Kei*; Huang, Z.*; Sugimoto, Kazuya*; Oyama, Kenji*; Happo, Naohisa*; Harada, Masahide; Oikawa, Kenichi; Inamura, Yasuhiro; Hayashi, Koichi*; et al.
ACS Applied Energy Materials (Internet), 4(5), p.5123 - 5131, 2021/05
Times Cited Count:13 Percentile:60.29(Chemistry, Physical)Oikawa, Kenichi; Harjo, S.; Pham, A. H.*; Kawasaki, Takuro; Morito, Shigekazu*; Kiyanagi, Yoshiaki*; Shinohara, Takenao; Kai, Tetsuya; Oba, Takuya*; Ito, Masakazu*
JPS Conference Proceedings (Internet), 33, p.011062_1 - 011062_6, 2021/03
Tsuchikawa, Yusuke; Abe, Yuta; Oishi, Yuji*; Kai, Tetsuya; Toh, Yosuke; Segawa, Mariko; Maeda, Makoto; Kimura, Atsushi; Nakamura, Shoji; Harada, Masahide; et al.
JPS Conference Proceedings (Internet), 33, p.011074_1 - 011074_6, 2021/03
In the decommissioning of the Fukushima-Daiichi (1F) Nuclear Power Plant, it is essential to understand characteristics of the melted core materials. The estimation of boride in the real debris is of great importance to develop safe debris removal plans. Hence, it is required to investigate the amount of boron in the melted core materials with nondestructive methods. Prompt gamma-ray activation analysis (PGAA) is one of the useful techniques to determine the amount of borides by means of the 478 keV prompt gamma-ray from neutron absorption reaction of boron. Moreover, it is well known that the width of the 478 keV gamma-ray peak is typically broadened due to the Doppler effect. The degree of the broadening is affected by coexisting materials, and can be recognized by the width of the prompt gamma-ray peak. As a feasibility study, the prompt gamma-ray from boride samples were measured using the ANNRI, NOBORU, and RADEN beamlines at the Materials and Life Science Experimental Facility (MLF) of Japan Proton Accelerator Complex (J-PARC).