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Tamura, Fumihiko; Okita, Hidefumi; Hotchi, Hideaki*; Saha, P. K.; Meigo, Shinichiro; Yoshii, Masahito*; Omori, Chihiro*; Yamamoto, Masanobu; Seiya, Kiyomi*; Sugiyama, Yasuyuki*; et al.
Proceedings of 20th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.64 - 68, 2023/11
The J-PARC 3GeV synchrotron (RCS) provides high intensity proton beams to the Materials and Life Science Experimental Facility (MLF) and the Main Ring (MR). The harmonic number (h) of the RCS is 2 and the RCS normally accelerates two bunches. For some experiments at the MLF, a single bunch is preferred. In this case, one of the rf bucket is filled with protons and the other is empty. Therefore the beam intensity is halved. If the RCS can accelerate with h=1, the intensity per bunch can be doubled, enabling to provide single bunch beams to the MLF with the maximum intensity. This possibly increases the MR beam power by injecting high intensity single bunches eight times. In this presentation, we report mainly on the consideration of h=1 acceleration in the RCS by longitudinal simulations.
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.
Yamamoto, Kazami; Yamamoto, Masanobu; Yamazaki, Yoshio; Nomura, Masahiro; Suganuma, Kazuaki; Fujirai, Kosuke; Kamiya, Junichiro; Hatakeyama, Shuichiro; Hotchi, Hideaki; Yoshimoto, Masahiro; et al.
Proceedings of 17th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.209 - 213, 2020/09
The J-PARC 3GeV Rapid Cycling Synchrotron (RCS) is aiming to provide the proton beam of very high power for neutron experiments and the main ring synchrotron. We have continued the beam commissioning and the output power from RCS have been increasing. In recent years, just before the summer shutdown period, we have been trying continuous supply of 1-MW high-intensity beam, which is the design value, to a neutron target. First trial was 1-hour continuous operation in July 2018, and second trial was 10-hours continuous in July 2019. In both cases, we achieved almost stable operation. Furthermore, in June 2020, we tried to operate continuously for over 40 hours. But in this case, some trouble occurred and the operation was frequently suspended. Through these continuous operation trials, we have identified issues for stable operation of 1 MW. In this presentation, we will report the results of 1-MW continuous operation and issues obtained from these results.
Sugiura, Yuki; Tomura, Tsutomu*; Ishidera, Takamitsu; Doi, Reisuke; Francisco, P. C. M.; Shiwaku, Hideaki; Kobayashi, Toru; Matsumura, Daiju; Takahashi, Yoshio*; Tachi, Yukio
Journal of Radioanalytical and Nuclear Chemistry, 324(2), p.615 - 622, 2020/05
Times Cited Count：4 Percentile：45.45(Chemistry, Analytical)Saha, P. K.; Shobuda, Yoshihiro; Hotchi, Hideaki; Harada, Hiroyuki; Hayashi, Naoki; Kinsho, Michikazu; Nomura, Masahiro; Tamura, Fumihiko; Tani, Norio; Watanabe, Yasuhiro; et al.
Proceedings of 7th International Particle Accelerator Conference (IPAC '16) (Internet), p.589 - 591, 2016/06
Ishizawa, Akihiro*; Idomura, Yasuhiro; Imadera, Kenji*; Kasuya, Naohiro*; Kanno, Ryutaro*; Satake, Shinsuke*; Tatsuno, Tomoya*; Nakata, Motoki*; Nunami, Masanori*; Maeyama, Shinya*; et al.
Purazuma, Kaku Yugo Gakkai-Shi, 92(3), p.157 - 210, 2016/03
The high-performance computer system Helios which is located at The Computational Simulation Centre (CSC) in The International Fusion Energy Research Centre (IFERC) started its operation in January 2012 under the Broader Approach (BA) agreement between Japan and the EU. The Helios system has been used for magnetised fusion related simulation studies in the EU and Japan and has kept high average usage rate. As a result, the Helios system has contributed to many research products in a wide range of research areas from core plasma physics to reactor material and reactor engineering. This project review gives a short catalogue of domestic simulation research projects. First, we outline the IFERC-CSC project. After that, shown are objectives of the research projects, numerical schemes used in simulation codes, obtained results and necessary computations in future.
Tamura, Fumihiko; Hotchi, Hideaki; Schnase, A.*; Yoshii, Masahito*; Yamamoto, Masanobu; Omori, Chihiro*; Nomura, Masahiro; Toda, Makoto*; Shimada, Taihei; Hasegawa, Katsushi*; et al.
Physical Review Special Topics; Accelerators and Beams, 18(9), p.091004_1 - 091004_8, 2015/09
Times Cited Count：4 Percentile：30.75(Physics, Nuclear)The RCS in the J-PARC was originally designed to accelerate two high intensity bunches, while some of neutron experiments in the MLF and a muon experiment using MR beams require a single bunch operation mode. The beam intensity in the single bunch operation has been limited by longitudinal beam losses due to the rf bucket distortions by the wake voltage of the odd harmonics in the wide band MA cavities. We installed an additional rf feedforward system to compensate the wake voltages of the odd harmonics (h=1,3,5). The longitudinal beam losses during the single bunch acceleration disappeared with feedforward for the odd harmonics. We also confirmed that the beam quality in the single bunch acceleration are similar to that of the normal operation with two bunches. Thus, high intensity single bunch acceleration at the intensity of 2.3
10
protons per bunch has been achieved in the J-PARC RCS.
Okamoto, Yoshihiro; Nakada, Masami; Akabori, Mitsuo; Shiwaku, Hideaki; Komamine, Satoshi*; Fukui, Toshiki*; Ochi, Eiji*; Nitani, Hiroaki*; Nomura, Masaharu*
Nihon Genshiryoku Gakkai Wabun Rombunshi, 11(2), p.127 - 132, 2012/06
Distribution and the chemical state of Ru element in the simulated high-level waste glass were examined by using the synchrotron radiation based X-ray imaging technique. In this technique, a direct X-ray CCD camera is used in place of an ion chamber. Position sensitive X-ray absorption spectra were obtained by analyzing gray scale in images of the X-ray CCD camera. At first, we measured a test sample containing RuO
and Ru metal powder. We successfully obtained information on the Ru distribution in the sample. In addition, the chemical state (oxide or metal ?) of each small Ru-rich spot was evaluated by the corresponding position sensitive XAFS spectrum. The imaging XAFS technique was applied to some simulated high-level waste glass samples. The Ru distribution of the glass sample and their chemical state were confirmed by image analyses. It can be seen that Ru element scattered in the glass sample exists as oxide RuO.
Nishio, Takahiro*; An, Toshu*; Nomura, Atsushi*; Miyachi, Kosuke*; Eguchi, Toyoaki*; Sakata, Hideaki*; Lin, S.*; Hayashi, Nobuhiko; Nakai, Noriyuki; Machida, Masahiko; et al.
Physical Review Letters, 101(16), p.167001_1 - 167001_4, 2008/10
Times Cited Count：98 Percentile：93.22(Physics, Multidisciplinary)Superconductivity of nanosized Pb-island structures whose radius is 0.8 to 2.5 times their coherence length was studied under magnetic fields using low-temperature scanning tunneling microscopy and spectroscopy. Spatial profiles of superconductivity were obtained by conductance measurements at zero-bias voltage. Critical magnetic fields for vortex penetration and expulsion and for superconductivity breaking were measured for each island. The critical fields depending on the lateral size of the islands and existence of the minimum lateral size for vortex formation were observed.
Yamasaki, Chisato*; Murakami, Katsuhiko*; Fujii, Yasuyuki*; Sato, Yoshiharu*; Harada, Erimi*; Takeda, Junichi*; Taniya, Takayuki*; Sakate, Ryuichi*; Kikugawa, Shingo*; Shimada, Makoto*; et al.
Nucleic Acids Research, 36(Database), p.D793 - D799, 2008/01
Times Cited Count：51 Percentile：71.25(Biochemistry & Molecular Biology)Here we report the new features and improvements in our latest release of the H-Invitational Database, a comprehensive annotation resource for human genes and transcripts. H-InvDB, originally developed as an integrated database of the human transcriptome based on extensive annotation of large sets of fulllength cDNA (FLcDNA) clones, now provides annotation for 120 558 human mRNAs extracted from the International Nucleotide Sequence Databases (INSD), in addition to 54 978 human FLcDNAs, in the latest release H-InvDB. We mapped those human transcripts onto the human genome sequences (NCBI build 36.1) and determined 34 699 human gene clusters, which could define 34 057 protein-coding and 642 non-protein-coding loci; 858 transcribed loci overlapped with predicted pseudogenes.
Li(
, n)
B reactionIshiyama, Hironobu*; Hashimoto, Takashi; Ishikawa, Tomoko*; Watanabe, Yutaka*; Das, S. K.*; Miyatake, Hiroari; Mizoi, Yutaka*; Fukuda, Tomokazu*; Tanaka, Masahiko*; Fuchi, Yoshihide*; et al.
Physics Letters B, 640(3), p.82 - 85, 2006/09
Times Cited Count：33 Percentile：84.97(Astronomy & Astrophysics)The excitation function of the 
Li(,n)B reaction was measured while identifying the final state event by event in the region of E
= 0.7 - 2.6 MeV using a highly efficient detector system and a low-energy Li beam. The results are much improved both in statistics and precisions, and show smaller cross sections than those of previous measurements by a factor of more than 2 in the low-energy region of E
1.5 MeV. A resonance-like structure is found at around E = 0.85 MeV.
Li(,n)B reaction for astrophysical interestDas, S. K.*; Fukuda, Tomokazu*; Mizoi, Yutaka*; Ishiyama, Hironobu*; Miyatake, Hiroari*; Watanabe, Yutaka*; Hirayama, Yoshikazu*; Tanaka, Masahiko*; Yoshikawa, Nobuharu*; Jeong, S.-C.*; et al.
AIP Conference Proceedings 847, p.374 - 376, 2006/07
no abstracts in English
Yachi, Shigeyasu; Sato, Tadashi; Suga, Shinichi*; Komuro, Yuichi; Uchida, Masaaki; Nakajima, Kunihisa; Nakamura, Jinichi; Amezawa, Hiroo; Omura, Hideaki*; Minato, Kazuo; et al.
JAERI-Review 2003-025, 162 Pages, 2003/09
JAERI-Review-2003-025.pdf:5.96MB
The report contains example of answers to the Problems of 31st(1999) to 35th(2003) Examinations for the Chief Engineer of Nuclear Fuel which were conducted as a national qualification examination. Brief explanations or references are given to some answers.
Okamoto, Yoshihiro; Nakada, Masami; Akabori, Mitsuo; Minato, Kazuo; Shiwaku, Hideaki; Komamine, Satoshi*; Fukui, Toshiki*; Nitani, Hiroaki*; Nomura, Masaharu*
no journal, ,
Chemical state analysis of Ru element scattered in an imitative glass matrix was performed by using the Imaging XAFS technique. Information on distribution of Ru element in the matrix was obtained from contrast values of CCD images before and after the Ru K-absorption edge. It is confirmed that the feature of the distributed element can be examined by getting XAFS spectra from the contrast information. We can get two kinds of XAFS spectra corresponding to Ru metal and oxide separately in the Imaging XAFS analysis.
Okamoto, Yoshihiro; Nakada, Masami; Akabori, Mitsuo; Minato, Kazuo; Shiwaku, Hideaki; Yaita, Tsuyoshi; Komamine, Satoshi*; Fukui, Toshiki*; Ochi, Eiji*; Nitani, Hiroaki*; et al.
no journal, ,
Distribution and the chemical state of Ru element in the simulated high-level waste glass were examined by using the synchrotron radiation based X-ray imaging technique. In this technique, a direct X-ray CCD camera is used in place of an ion chamber. Position sensitive X-ray absorption spectra were obtained by analyzing gray scale in images of the X-ray CCD camera. It can be seen that Ru element scattered in the glass sample exists as oxide RuO.
Nishiuchi, Mamiko; Pirozhkov, A. S.; Ogura, Koichi; Tanimoto, Tsuyoshi; Sakaki, Hironao; Hori, Toshihiko; Sagisaka, Akito; Yogo, Akifumi; Fukuda, Yuji; Kanasaki, Masato; et al.
no journal, ,
We present the results of the experiment of laser-driven proton acceleration with the interaction between laser and thin foil target. The maximum energy of the laser-driven protons increases as the intensity of the laser increases. In order to accelerate the proton beam toward higher energy with the limited energy of laser, we need to increase the intensity of the laser. For that purpose, we upgraded the laser mirrors in the beam line. As a result the intensity of the laser increases about one oreder of magnitude. With the tape target, we obtain proton beam whose maximum energy is 23 MeV. We also conducted the plasma mirror to increase the contrast of the laser. We show the detail of the proton acceleration results with the plasma mirror.
Nishiuchi, Mamiko; Pirozhkov, A. S.; Ogura, Koichi; Tanimoto, Tsuyoshi; Sakaki, Hironao; Hori, Toshihiko; Sagisaka, Akito; Yogo, Akifumi; Fukuda, Yuji; Kanasaki, Masato; et al.
no journal, ,
We present the results of the experiment of laser-driven proton acceleration by the interaction between laser and thin foil target. The maximum energy of the laser-driven protons increases as the intensity of the laser increases. In order to accelerate the proton beam toward higher energy with the limited energy of laser, we need to increase the intensity of the laser. For that purpose, we upgraded the laser mirrors in the beam line. As a result the intensity of the laser increases about one oreder of magnitude. With the tape target, we obtain proton beam whose maximum energy is 23 MeV. We also conducted the plasma mirror to increase the contrast of the laser. We show the detail of the proton acceleration results with the plasma mirror and nano-meter target.
Okamoto, Yoshihiro; Watanabe, So; Nagai, Takayuki; Kitawaki, Shinichi; Shibata, Atsuhiro; Nomura, Kazunori; Shiwaku, Hideaki
no journal, ,
Imaging XAFS analysis of simulated secondary waste generated from the treatment process of contaminated water in the Fukushima Daiichi Plant. The object in this study was titanate adsorption materials to collect strontium. Imaging XAFS data of the frame element Ti in the adsorption material and the target element Sr were obtained in the same domain of samples. Radiation effects in the secondary waste were simulated by 
-ray and electron beam irradiation.
Shimomura, Ryotaro*; Suzuki, Tomoya*; Motokawa, Ryuhei; Ueda, Yuki; Shiwaku, Hideaki; Koyama, Kazuya*; Narita, Hirokazu*
no journal, ,
no abstracts in English
