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Sueoka, Shigeru; Kawakami, Tetsuo*; Suzuki, Kota*; Kagami, Saya; Yokoyama, Tatsunori; Shibazaki, Bunichiro*; Nagata, Mitsuhiro; Yamazaki, Ayu*; Higashino, Fumiko*; King, G. E.*; et al.
Fisshion, Torakku Nyusureta, (36), p.1 - 3, 2023/12
no abstracts in English
Shimomura, Koichiro*; Koda, Akihiro*; Pant, A. D.*; Natori, Hiroaki*; Fujimori, Hiroshi*; Umegaki, Izumi*; Nakamura, Jumpei*; Tampo, Motonobu*; Kawamura, Naritoshi*; Teshima, Natsuki*; et al.
Journal of Physics; Conference Series, 2462, p.012033_1 - 012033_5, 2023/03
Fukuda, Tatsuo; Kobata, Masaaki; Shobu, Takahisa; Yoshii, Kenji; Kamiya, Junichiro; Iwamoto, Yosuke; Makino, Takahiro*; Yamazaki, Yuichi*; Oshima, Takeshi*; Shirai, Yasuhiro*; et al.
Journal of Applied Physics, 132(24), p.245102_1 - 245102_8, 2022/12
Times Cited Count:0 Percentile:18.86(Physics, Applied)Direct energy conversion has been investigated using Ni/SiC Schottky junctions with the irradiation of monochromatized synchrotron X-rays simulating the gamma rays of Np (30 keV) and Am (60 keV). From current-voltage measurements, electrical energies were obtained for both kinds of gamma rays. The energy conversion efficiencies were found to reach up to 1.6%, which is comparable to those of a few other semiconducting systems reported thus far. This result shows a possibility of energy recovery from nuclear wastes using the present system, judging from the radiation tolerant nature of SiC. Also, we found different conversion efficiencies between the two samples. This could be understandable from hard X-ray photoelectron spectroscopy and secondary ion mass spectroscopy measurements, suggesting the formation of Ni-Si compounds at the interface in the sample with a poor performance. Hence, such combined measurements are useful to provide information that cannot be obtained by electrical measurements alone.
Suzuki, Kota*; Kawakami, Tetsuo*; Sueoka, Shigeru; Yamazaki, Ayu*; Kagami, Saya; Yokoyama, Tatsunori; Tagami, Takahiro*
Island Arc, 31(1), p.e12462_1 - e12462_15, 2022/09
Times Cited Count:1 Percentile:37.23(Geosciences, Multidisciplinary)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:3 Percentile:80.29(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.
Okubo, Takahiro*; Yamazaki, Akio*; Fukatsu, Yuta; Tachi, Yukio
Microporous and Mesoporous Materials, 313, p.110841_1 - 110841_11, 2021/01
Times Cited Count:2 Percentile:30.86(Chemistry, Applied)Pore distributions in water-saturated Ca-montmorillonite were investigated using H NMR measurements under various dry densities (0.8 - 1.6 g/cm) and porewater salinity conditions (deionized water, 0.1 and 1 M CaCl), at the temperature range of 233 - 303 K. The volume fractions of the interlayer pore including two and three hydrated layers and the non-interlayer pore in compacted Ca-montmorillonite were quantified by NMR relaxometry including and distribution analysis, and were compared with NMR cryoporometry and X-ray diffractometry. These analysis provided consistent pictures on the pore distributions in compacted Ca-montmorillonite, in contrast to Na-montmorillonite. The main factor affecting the pore distribution in compacted Ca- and Na-montmorillonite is the density, whereas the effect of porewater salinity is relatively smaller. The effect of interlayer cations is also relatively smaller at higher density, although the differences in the pore structures are significant at low density.
Ishikawa, Takatsugu*; Fujimura, Hisako*; Fukasawa, Hiroshi*; Hashimoto, Ryo*; He, Q.*; Honda, Yuki*; Hosaka, Atsushi; Iwata, Takahiro*; Kaida, Shun*; Kasagi, Jirota*; et al.
Physical Review C, 101(5), p.052201_1 - 052201_6, 2020/05
Sue, Yuki*; Yotsuzuka, Mai*; Futatsukawa, Kenta*; Hasegawa, Kazuo; Iijima, Toru*; Iinuma, Hiromi*; Inami, Kenji*; Ishida, Katsuhiko*; Kawamura, Naritoshi*; Kitamura, Ryo; et al.
Physical Review Accelerators and Beams (Internet), 23(2), p.022804_1 - 022804_7, 2020/02
A destructive monitor to measure the longitudinal bunch width of a low-energy and low-intensity muon beam was developed. This bunch-width monitor (BWM) employed microchannel plates to detect a single muon with high time resolution. In addition, constant-fraction discriminators were adopted to suppress the time-walk effect. The time resolution was measured to be 65 ps in rms using a picosecond-pulsed laser. This resolution satisfied the requirements of the muon linac of the J-PARC E34 experiment. We measured the bunch width of negative-muonium ions accelerated with a radio-frequency quadrupole using the BWM. The bunch width was successfully measured to be 54 11 ns, which is consistent with the simulation.
Sue, Yuki*; Iijima, Toru*; Inami, Kenji*; Yotsuzuka, Mai*; Iinuma, Hiromi*; Nakazawa, Yuga*; Otani, Masashi*; Kawamura, Naritoshi*; Shimomura, Koichiro*; Futatsukawa, Kenta*; et al.
Proceedings of 16th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.55 - 60, 2019/07
The result of bunch size measurement of muon accelerated by RFQ up to 89 keV is presented in this paper. A four-stage muon linac for precise measurement of muon property is under construction in the J-PARC. The demonstration of the first muon RF acceleration with an RFQ linac was conducted and the transverse profile of the accelerated muons was measured in 2017. As one of the remaining issues for the beam diagnostic system, the longitudinal beam profile after the RFQ should be measured to match the profile to the designed acceptance of the subsequent accelerator. For this purpose, the new longitudinal beam monitor using the microchannel plate is under development. The time resolution of the monitor aims to be around 30 to 40 ps corresponding to 1% of a period of an operating frequency of the accelerator, which is 324 MHz. On November 2018, the bunch size of accelerated negative muonium ion of 89 keV with the RFQ was measured using this monitor at the J-PARC MLF. The measured bunch width is ns, which is consistent with the simulation.
Oguri, Hidetomo; Hasegawa, Kazuo; Ito, Takashi; Chishiro, Etsuji; Hirano, Koichiro; Morishita, Takatoshi; Shinozaki, Shinichi; Ao, Hiroyuki; Okoshi, Kiyonori; Kondo, Yasuhiro; et al.
Proceedings of 11th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.389 - 393, 2014/10
no abstracts in English
Tamura, Jun; Ao, Hiroyuki; Asano, Hiroyuki; Ikegami, Masanori*; Maruta, Tomofumi; Miura, Akihiko; Morishita, Takatoshi; Oguri, Hidetomo; Ouchi, Nobuo; Sawabe, Yuki*; et al.
Proceedings of 9th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.377 - 380, 2013/08
In the J-PARC linac, almost all the cavities and magnets have been precisely aligned because the accelerator tunnel has been deformed by the 2011 Tohoku Earthquake. In the beam transport line called MEBT2 and A0BT at the downstream of the drift tube linac, the beam duct has been roughly aligned after the precise alignment of the quadruple doublets. During the first beam operation after the earthquake, remarkable beam loss and residual radiation have been recognized at the MEBT2 and A0BT. As the result of the duct position measurement, the misalignement including over 10 mm shift from the beam axis was found. By conducting the beam duct realignment, the beam loss and the residual radiation were successfully decreased. In this paper, the procedure of the beam duct alignment and the beam loss due to the misalignment are described.
Miura, Kenta*; Sato, Takahiro; Ishii, Yasuyuki; Koka, Masashi; Kiryu, Hiromu*; Ozawa, Yusuke*; Takano, Katsuyoshi*; Okubo, Takeru; Yamazaki, Akiyoshi; Kada, Wataru; et al.
JAEA-Review 2012-046, JAEA Takasaki Annual Report 2011, P. 126, 2013/01
Miura, Kenta*; Sato, Takahiro; Ishii, Yasuyuki; Kiryu, Hiromu*; Ozawa, Yusuke*; Koka, Masashi; Takano, Katsuyoshi*; Okubo, Takeru; Yamazaki, Akiyoshi; Kada, Wataru; et al.
Key Engineering Materials, 534, p.158 - 161, 2013/00
Times Cited Count:5 Percentile:89.92Amano, Yuki; Yamamoto, Yoichi; Nanjo, Isao; Murakami, Hiroaki; Yokota, Hideharu; Yamazaki, Masanori; Kunimaru, Takanori; Oyama, Takahiro*; Iwatsuki, Teruki
JAEA-Data/Code 2011-023, 312 Pages, 2012/02
In the Horonobe Underground Research Laboratory (URL) Project, ground water from boreholes, river water and precipitation have been analyzed for the environmental monitoring since the fiscal year 2001. This report shows the data set of water chemistry since the fiscal year 2001 to the fiscal year 2010.
Miura, Kenta*; Sato, Takahiro; Ishii, Yasuyuki; Koka, Masashi; Uehara, Masato*; Kiryu, Hiromu*; Takano, Katsuyoshi*; Okubo, Takeru; Yamazaki, Akiyoshi; Kada, Wataru; et al.
JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 126, 2012/01
Sato, Takahiro; Koka, Masashi; Kada, Wataru; Yokoyama, Akihito; Okubo, Takeru; Yamazaki, Akiyoshi; Ishii, Yasuyuki; Kamiya, Tomihiro
JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 83, 2012/01
Endo, Kiyoshi*; Shibata, Yasushi*; Yamamoto, Tetsuya*; Nakai, Kei*; Matsumura, Akira*; Sato, Takahiro; Yokoyama, Akihito; Koka, Masashi; Okubo, Takeru; Yamazaki, Akiyoshi; et al.
JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 86, 2012/01
Sakurai, Eiko*; Yanai, Kazuhiko*; Ishii, Keizo*; Fujiki, Kota*; Hiraishi, Shingo*; Yamazaki, Hiromichi*; Matsuyama, Shigeo*; Okamura, Nobuyuki*; Yokoyama, Akihito; Kada, Wataru; et al.
JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 84, 2012/01
Harada, Satoshi*; Ehara, Shigeru*; Ishii, Keizo*; Sato, Takahiro; Yamazaki, Hiromichi*; Matsuyama, Shigeo*; Kamiya, Tomihiro
JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 89, 2012/01
Miura, Kenta*; Machida, Yuki*; Uehara, Masato*; Kiryu, Hiromu*; Ozawa, Yusuke*; Sasaki, Tomoyuki*; Hanaizumi, Osamu*; Sato, Takahiro; Ishii, Yasuyuki; Koka, Masashi; et al.
Key Engineering Materials, 497, p.147 - 150, 2012/00
Times Cited Count:7 Percentile:95.17