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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：10 Percentile：74.97(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.
Nakanoya, Takamitsu; Yoshimoto, Masahiro; Yamazaki, Yoshio; Takeda, Osamu*; Saeki, Riuji*; Muto, Masayoshi*
Proceedings of 16th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.545 - 549, 2019/07
In the 3 GeV Rapid Cycling Synchrotron (RCS) of the Japan Proton Accelerator Research complex (J-PARC), we adopted the carbon stripper foil for the multi-turn H- charge exchange injection. The charge exchange foil which use in RCS is fabricated by the arc discharge method with the boron doped carbon electrode. The foil fabricated this method is called HBC foil (Hybrid Boron mixed Carbon stripper foil). HBC foil had been developed at KEK. It has high durability for the beam irradiation damage. In past days, the foil fabrication process was conducted in KEK Tsukuba-site and the foil preparation process was conducted in JAEA Tokai-site. In 2017, the foil deposition apparatus has been relocated from KEK to JAEA, and we started both processes in Tokai-site. We carried out the offline beam irradiation test for the new HBC foil which fabricated in JAEA, and we confirmed that its performance is equivalent to the original HBC foil. Next we tested a new HBC foil with actual beam in RCS and we confirmed it could withstand 1 week beam irradiation. After that, we started user operation with the new HBC foil in 2018. So far we accomplished stable user operation for one year by using the new HBC foil only.
Strasser, P.*; Abe, Mitsushi*; Aoki, Masaharu*; Choi, S.*; Fukao, Yoshinori*; Higashi, Yoshitaka*; Higuchi, Takashi*; Iinuma, Hiromi*; Ikedo, Yutaka*; Ishida, Katsuhiko*; et al.
EPJ Web of Conferences, 198, p.00003_1 - 00003_8, 2019/01
Times Cited Count：18 Percentile：98.46(Quantum Science & Technology)Tobita, Norimitsu; Yoshimoto, Masahiro; Takeda, Osamu; Saeki, Riuji; Yamazaki, Yoshio; Kinsho, Michikazu; Muto, Masayoshi*
Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1350 - 1354, 2015/09
no abstracts in English
Osamura, Kozo*; Machiya, Shutaro*; Hampshire, D. P.*; Tsuchiya, Yoshinori*; Shobu, Takahisa; Kajiwara, Kentaro*; Osabe, Goro*; Yamazaki, Kohei*; Yamada, Yuichi*; Fujikami, Jun*
Superconductor Science and Technology, 27(8), p.085005_1 - 085005_11, 2014/08
Times Cited Count：33 Percentile：74.59(Physics, Applied)Tobita, Norimitsu; Yoshimoto, Masahiro; Yamazaki, Yoshio; Saeki, Riuji; Okabe, Kota; Kinsho, Michikazu; Takeda, Osamu*; Muto, Masayoshi*
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.915 - 919, 2014/06
The charge conversion foil used with a J-PARC 3GeV synchrotron (RCS: Rapid Cycling Synchrotron) is a thin film made from carbon about 1 micrometer thick, and it radioactivates it by continuing being irradiated with a beam. Moreover, generally it is thought that degradation progresses and foil itself breaks easily. However, when dealing with the foil after irradiation, the measure against the danger of the contamination and the contamination in the living body by foil dispersing is one of the subjects. So, in RCS, the foil exchange booth for collecting the radioactivated foil safely and certainly was installed. Even when dispersing foil temporarily, the radioactivated foil can be shut up only in Booth and a worker's contamination and contamination of work area could be prevented. Moreover, when it sees from a viewpoint of the performance gain of foil, analysis and observation of the collected foil are one of the important issues. Then, in order to observe the radioactivated foil after beam irradiation, the transparent protective case which can be sealed with a foil frame simple substance was developed. In this announcement, the equipment developed in order to collect the charge conversion foil after beam irradiation, and the established technique are announced in detail.
Saeki, Riuji; Yoshimoto, Masahiro; Yamazaki, Yoshio; Tobita, Norimitsu; Okabe, Kota; Kinsho, Michikazu; Takeda, Osamu*; Muto, Masayoshi*
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.523 - 526, 2014/06
RCS has loaded with the foil of 15 sheets including a reserve into equipment so that it can exchange in a short time, when foil is damaged also in a beam operating period. It is difficult for foil to be made of a thin film about 1 micrometer thick, and to treat as it is. Then, foil is fixed to the frame which stuck the SiC fiber, and foil is not touched, but only a frame is held, and it enabled it to operate it. The following preparations are needed as new foil exchange work. (1) Exfoliation and recovery of foil which have been vapor-deposited to glass substrate. (2) Dryness and logging of exfoliative foil. (3) Preparation of SiC wire, and attachment on frame. (4) Fix foil to a frame. (5) Although charge on a magazine-rack was performed manually altogether until now, there were many work man days, and the quality of the prepared foil had variation. Then, equipment required in order to secure reproducibility was developed. The technique for working efficiently simultaneously was established. In this announcement, the technique established until now and the developed jigs are announced in detail.
Kawase, Masato; Yoshimoto, Masahiro; Yamazaki, Yoshio; Takeda, Osamu
Proceedings of 9th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.734 - 737, 2013/08
no abstracts in English
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：87.54(Nanoscience & Nanotechnology)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
m band using focused proton beamMiura, 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：93.85(Engineering, Electrical & Electronic)m band using focused proton beamMiura, 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, 2011/12
Times Cited Count：6 Percentile：2.48Saeki, Riuji; Yoshimoto, Masahiro; Yamazaki, Yoshio; Takeda, Osamu; Kinsho, Michikazu
Proceedings of 7th Annual Meeting of Particle Accelerator Society of Japan (DVD-ROM), p.1025 - 1028, 2010/08
no abstracts in English
Yoshimoto, Masahiro; Takeda, Osamu; Kawase, Masato; Yamazaki, Yoshio; Kinsho, Michikazu; Saito, Yoshio*; Kabeya, Zenzaburo*
Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.3930 - 3932, 2010/05
At the 3 GeV RCS (Rapid Cycling Synchrotron) in J-PARC (Japan Proton Accelerator Research Complex), the scheme of H
charge exchange injection using stripping foils is adopted. The charge exchange system is composed of three stripping foil devices. The first stripping foil device, which converts the H
beam from the 181 MeV LINAC into the H beam, can replace the broken foil with new one in vacuum remotely and automatically. In September 2007, mechanical trouble with the first stripping foil device had occurred just before the RCS beam commissioning was started. The magnetic coupling of the transfer rod had been decoupled and the transfer rod had been broken which was caught in the vacuum gate valve. We studied the trouble cause, re-examined the structural design and the selection for the material, and then verified the specification from endurance tests with sample pieces. Then the improved device was installed in the ring in September 2008.
Kawase, Masato; Yoshimoto, Masahiro; Takeda, Osamu; Yamazaki, Yoshio; Kinsho, Michikazu
Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.214 - 216, 2010/05
The foil exchange device consists of a vacuum system and a foil driving system. Therefore it is necessary to be able to control under the unified management of the vacuum system and foil driving system. We developed the control system that unifies management for the charge exchange system. The charge exchange device is controlled by the two kinds of controllers. One is the Programmable Logic Controller (PLC) to operate the vacuum system, and the other is the Multi Control Unit (MCU) to operate the foil driving system. Unifying management these device involve the workstation. Therefore we were able to control under the unified management of two controllers by the workstation. It is possible to control the accelerator devices using EPICS in J-PARC. Therefore this device has to support EPICS. We introduce the reconstruction of the control system for the charge exchange system at the RCS in J-PARC.
Yamazaki, Yoshio; Yoshimoto, Masahiro; Takeda, Osamu; Kinsho, Michikazu; Sugai, Isao*
Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.3924 - 3926, 2010/05
J-PARC requires thick carbon stripper foils to strip electrons from the H
beam supplied by the linac before injection into the Rapid Cycling Synchrotron (RCS). Foil thickness is about 200 g/cm
corresponding to conversion efficiency of 99.7% from the primary H beams of 181 MeV energy to H
. For this purpose, we have successfully developed hybrid type thick boron-doped carbon (HBC) stripper foils, which showed a drastic improvement not only with respect to the lifetime, but also with respect to thickness reduction and shrinkage at high temperature during long beam irradiation. We started to study carbon stripper foils microscopically why carbon foils have considerable endurance for the beam impact by boron-doped. At first, we made a comparison between nominal carbon and HBC by the electric microscope and ion-induced analysis.
Kamiya, Junichiro; Kinsho, Michikazu; Kuramochi, Masaya; Takayanagi, Tomohiro; Takeda, Osamu; Ueno, Tomoaki; Watanabe, Masao; Yamamoto, Kazami; Yamazaki, Yoshio; Yoshimoto, Masahiro
IEEE Transactions on Applied Superconductivity, 18(2), p.293 - 296, 2008/06
Times Cited Count：3 Percentile：25.37(Engineering, Electrical & Electronic)The kicker magnets are installed in the extraction section in the Rapid Cycling Synchrotron (RCS) of J-PARC and they extract a proton beam accelerated up to 3 GeV. We performed the mapping in the air applying one third of operational voltage after checking linear dependence of magnetic field with excitation current. A short search coil with the 3-axias stage was used to measure the magnetic field distribution. The results showed that the distribution in the medium plane of the same type of kicker magnet is in good agreement with each other. The excitation test with the operational charging voltage of 60 kV was also performed in a vacuum. At the first stage, we were bothered by the electric breakdown. It was noticed that the reduction of outgassing rate by baking is very effective to suppress the discharge. Pressure and mass spectrum measured during the excitation test showed that the excitation of the kicker magnet has conditioning effect.
Yoshimoto, Masahiro; Ueno, Tomoaki; Togashi, Tomohito; Toyokawa, Ryoji; Takeda, Osamu; Watanabe, Masao; Yamazaki, Yoshio; Yamamoto, Kazami; Kamiya, Junichiro; Takayanagi, Tomohiro; et al.
IEEE Transactions on Applied Superconductivity, 18(2), p.301 - 305, 2008/06
Times Cited Count：1 Percentile：12.53(Engineering, Electrical & Electronic)Yoshimoto, Masahiro; Ueno, Tomoaki; Togashi, Tomohito; Takeda, Osamu; Kanazawa, Kenichiro; Watanabe, Masao; Yamazaki, Yoshio; Kamiya, Junichiro; Takayanagi, Tomohiro; Kuramochi, Masaya; et al.
IEEE Transactions on Applied Superconductivity, 18(2), p.297 - 300, 2008/06
Times Cited Count：4 Percentile：30.08(Engineering, Electrical & Electronic)