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Miyao, Tomoaki*; Igarashi, Zenei*; Miura, Akihiko; Mayama, Minoru*
Proceedings of 9th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.571 - 573, 2013/08
no abstracts in English
Miura, Akihiko; Hasegawa, Kazuo; Oguri, Hidetomo; Ouchi, Nobuo; Igarashi, Zenei*; Miyao, Tomoaki*; Ikegami, Masanori*
Proceedings of 2nd International Particle Accelerator Conference (IPAC 2011) (Internet), p.2328 - 2330, 2011/09
On March 11, 2011, the great earthquake occurred off the Pacific coast of Tohoku. This earthquake and related ones caused the big damage of the J-PARC accelerators. As for the beam monitors in J-PARC linac, some commissioning tools had damage and the vacuum leakage was observed. In the recovery work, we inspected the damage and put the emergency steps for the vacuum equipment. In this paper, detailed inspection results of beam monitors are described and also the recovery work is introduced.
Miura, Akihiko; Maruta, Tomofumi; Sako, Hiroyuki; Hasegawa, Kazuo; Ouchi, Nobuo; Igarashi, Zenei*; Miyao, Tomoaki*; Ikegami, Masanori*
Proceedings of 2nd International Particle Accelerator Conference (IPAC 2011) (Internet), p.1257 - 1259, 2011/09
Ar-CO
gas proportional beam loss monitors (BLMs) have measured the beam loss through operations, but they are also sensitive to background noise of X-ray emitted from RF cavities. For the future energy upgrade of J-PARC linac, because 21 RF cavities are additionally installed in the beam line, the background noise would be serious problem. We employed the scintillation monitors to measure the beam loss which would bring more accurate beam loss measurements with suppression of X-ray noise. As the measurement results, a good signal to noise ratio is observed for the scintillation monitor with quite low sensitivity to the background X-ray. In addition, the availability of the scintillation monitor is also confirmed at the low energy part. This paper describes the beam loss measurement system using a scintillation monitor.
Miura, Akihiko; Maruta, Tomofumi; Sako, Hiroyuki; Hasegawa, Kazuo; Ouchi, Nobuo; Igarashi, Zenei*; Miyao, Tomoaki*; Ikegami, Masanori*
Proceedings of 10th European Workshop on Beam Diagnostics and Instrumentation for Particle Accelerators (DIPAC 2011) (Internet), p.149 - 151, 2011/08
Ar-CO gas proportional beam loss monitors (BLMs) have measured the beam loss through operations, but they are also sensitive to background noise of X-ray emitted from RF cavities. For the future energy upgrade of J-PARC linac, because 21 RF cavities are additionally installed in the beam line, the background noise would be serious problem. We employed the scintillation monitors to measure the beam loss which would bring more accurate beam loss measurements with suppression of X-ray noise. As the measurement results, a good signal to noise ratio is observed for the scintillation monitor with quite low sensitivity to the background X-ray. This paper describes the beam loss measurement system using a scintillation monitor.
Miura, Akihiko; Sato, Susumu; Tomisawa, Tetsuo; Igarashi, Zenei*; Miyao, Tomoaki*; Ikegami, Masanori*; Toyama, Takeshi*
Proceedings of 10th European Workshop on Beam Diagnostics and Instrumentation for Particle Accelerators (DIPAC 2011) (Internet), p.50 - 52, 2011/08
J-PARC had developed the beam diagnostic devices for the present J-PARC linac and has used them since the operation start. J-PARC linac began the energy upgrade project since 2009 and 21 ACS cavities will be installed. Because the beam parameters are updated due to the project, new beam diagnostic devices are additionally fabricated and the diagnostic devices at the downstream part where the beam energy will be increased up to 400 MeV by ACS cavities should be developed. In this paper, we introduce the development of the beam diagnostic devices for the project and the new developing devices.
Miura, Akihiko; Maruta, Tomofumi; Sako, Hiroyuki; Hasegawa, Kazuo; Ouchi, Nobuo; Igarashi, Zenei*; Miyao, Tomoaki*; Ikegami, Masanori*
Proceedings of 8th Annual Meeting of Particle Accelerator Society of Japan (Internet), 3 Pages, 2011/08
Ar-CO gas proportional beam loss monitors (BLMs) have measured the beam loss through operations, but they are also sensitive to background noise of X-ray emitted from RF cavities. For the future energy upgrade of J-PARC linac, because 21 RF cavities are additionally installed in the beam line, the background noise would be serious problem. We employed the scintillation monitors to measure the beam loss which would bring more accurate beam loss measurements with suppression of X-ray noise. As the measurement results, a good signal to noise ratio is observed for the scintillation monitor with quite low sensitivity to the background X-ray. This paper describes the beam loss measurement system using a scintillation monitor.
Miura, Akihiko; Sako, Hiroyuki; Yamamoto, Kazami; Kikuzawa, Nobuhiro; Maruta, Tomofumi; Sato, Susumu; Imai, Kenichi; Adachi, Satoshi; Sugimura, Hitoshi; Igarashi, Zenei*; et al.
Proceedings of 25th International Linear Accelerator Conference (LINAC 2010) (CD-ROM), p.590 - 592, 2010/09
Ar-CO gas proportional counters are employed for the measurement of beam loss in the current linac operation, but they are also sensitive to background noise of X-ray emitted from RF cavities. In SDTL section, protons, secondary hadrons and 
rays would be mainly generated as a beam loss, but it is not easy to estimate real beam loss using the proportional counter. The plastic scintillation counters with less X-ray sensitivity and 
He proportional counters with high thermal neutron sensitivity will be also employed to measure the beam loss. This paper reports the signals obtained during the beam operation using the Ar-CO gas proportional counter and the plastic scintillation counter. Finally, a measurement of emission position and angle distributions of protons due to negative hydrogen ion (H
) beam loss is being planed. This plan is introduced and this result would lead to clarify the source of beam loss.
Sato, Susumu; Miura, Akihiko; Igarashi, Zenei*; Ikegami, Masanori*; Ueno, Akira; Sako, Hiroyuki; Morishita, Takatoshi; Yoshikawa, Hiroshi; Hasegawa, Kazuo; Kobayashi, Tetsuya
Proceedings of 6th Annual Meeting of Particle Accelerator Society of Japan (CD-ROM), p.298 - 300, 2010/03
no abstracts in English
Miura, Akihiko; Sato, Susumu; Sako, Hiroyuki; Yoshikawa, Hiroshi; Hasegawa, Kazuo; Igarashi, Zenei*; Ikegami, Masanori*
Proceedings of 6th Annual Meeting of Particle Accelerator Society of Japan (CD-ROM), p.733 - 735, 2010/03
no abstracts in English
Sato, Susumu; Miura, Akihiko; Tomisawa, Tetsuo; Sako, Hiroyuki; Morishita, Takatoshi; Ueno, Akira; Hasegawa, Kazuo; Yoshikawa, Hiroshi; Igarashi, Zenei*; Ikegami, Masanori*
Proceedings of 2009 Particle Accelerator Conference (PAC '09) (DVD-ROM), p.3591 - 3593, 2009/05
Sato, Susumu; Igarashi, Zenei*; Tomisawa, Tetsuo; Miura, Akihiko; Ueno, Akira; Sako, Hiroyuki; Morishita, Takatoshi; Kondo, Yasuhiro; Shen, G.; Akikawa, Hisashi*; et al.
Proceedings of 5th Annual Meeting of Particle Accelerator Society of Japan and 33rd Linear Accelerator Meeting in Japan (CD-ROM), p.500 - 502, 2008/00
no abstracts in English
Akikawa, Hisashi*; Igarashi, Zenei*; Ikegami, Masanori*; Lee, S.*; Sato, Susumu; Shen, G.; Tomisawa, Tetsuo; Ueno, Akira
Proceedings of 2007 Particle Accelerator Conference (PAC '07) (Internet), p.1472 - 1474, 2007/08
Beam commissioning of J-PARC linac has been performed since November 2006. We have wire scanners in order to measure beam profile and perform transverse matching. Four wire scanners are installed at each matching section. We report the result of measurement of beam profile and matching.
Sato, Susumu; Tomisawa, Tetsuo; Sako, Hiroyuki; Shen, G.; Ueno, Akira; Akikawa, Hisashi*; Igarashi, Zenei*; Lee, S.*; Ikegami, Masanori*; Kamikubota, Norihiko*
Proceedings of 2007 Particle Accelerator Conference (PAC '07) (Internet), p.4072 - 4074, 2007/08
The beam commissioning of J-PARC LINAC has been started in November 2006. Beam Position Monitors (BPM's) which had been calibrated on the bench setup with a scanning wire, take beam-based-calibration method in order to enable the beam to pass at the centre of a quadrupole magnet (Q-magnet). The installed BPM's and their calibration methods are described.
Ikegami, Masanori*; Lee, S.*; Akikawa, Hisashi*; Igarashi, Zenei*; Kondo, Yasuhiro; Okawa, Tomohiro; Ueno, Akira; Sako, Hiroyuki; Ao, Hiroyuki; Sato, Susumu; et al.
KEK Proceedings 2006-15 (CD-ROM), p.347 - 349, 2007/03
We plan to start the beam commissioning of J-PARC linac with reduced energy of 181 MeV in the end of this year. Detailed commissioning strategies for the linac and the succeeding beam transport line, to which we refer as L3BT or Linac-to-3-GeV-synchrotron Beam Transport, will be presented in this talk. The emphasis will be put on the commissioning procedures for two debuncher cavities and a transverse collimator system located in L3BT, because they are key elements in determining the final beam quality at the injection point to the succeeding 3-GeV synchrotron. The unique design and features of the collimator system are also presented.
Sato, Susumu; Tomisawa, Tetsuo; Kondo, Yasuhiro; Ueno, Akira; Akikawa, Hisashi*; Igarashi, Zenei*; Lee, S.*; Kubota, Chikashi*; Ikegami, Masanori*
Proceedings of 23rd International Linear Accelerator Conference (LINAC 2006) (CD-ROM), p.268 - 270, 2007/00
In the J-PARC LINAC, upgrade of beam diagnostics of LEBT and MEBT is taken. Three beam current monitors and two beam phase monitors are added. In the LEBT and MEBT section, large number of accelerator devices are placed. Therefore to save the space, several modifications are needed, for example, additional monitors need to be welded with each other. Those details of the upgrade of beam diagnostics system are described.
Sato, Kenichiro; Hiroki, Seiji; Lee, S.*; Hayashi, Naoki; Yamamoto, Kazami; Hiramatsu, Shigenori*; Toyama, Takeshi*; Arakawa, Dai*; Igarashi, Zenei*; Saeki, Riuji
Proceedings of 4th Annual Meeting of Particle Accelerator Society of Japan and 32nd Linear Accelerator Meeting in Japan (CD-ROM), p.297 - 299, 2007/00
At the injection and H0 dump line of J-PARC RCS, different beam monitors have been installed. Main purpose of the beam monitors in the injection line is to generate a beam position and profile to adjust the injection trajectory to the RCS ring. To guide the injected beam precisely is, needless to say, required to reduce the beam loss in the ring. Hence the monitor system is one of the most essential to operate the RCS. At the injection point, there are also some beams that are not match the RCS ring, that is negative and neutral proton beam. H0 dump accepts the unsuitable beams through the H0 dump line. The power limitation of the H0 dump is 4 kW. The monitor system in the dump line is to handle the beam and to monitor the dumped beam power. At the conference these monitor systems will be outlined.
Sato, Susumu; Tomisawa, Tetsuo; Ao, Hiroyuki; Ueno, Akira; Akikawa, Hisashi*; Igarashi, Zenei*; Lee, S.*
Proceedings of 10th European Particle Accelerator Conference (EPAC 2006) (CD-ROM), p.1151 - 1153, 2006/00
In the LINAC section of J-PARC, we have several type of sensors of monitor, i.e, Beam Position Monitor, Beam Profile Monitor, Beam Size Monitor, Current Monitor, Beam Phase Monitor, Beam Loss Monitor. Those sensors are being installed currently. The procedures, remarks during the installation, status are described in this paper. As an examle, the beam postion monitors are one of sensors which are taken cared intensively for their positioning on their housing quadrupole magnet, then our cares during their installation are described.
Sato, Susumu; Igarashi, Zenei*; Akikawa, Hisashi*; Tomisawa, Tetsuo; Lee, S.*; Ueno, Akira; Ikegami, Masanori*; Ao, Hiroyuki
Proceedings of 3rd Annual Meeting of Particle Accelerator Society of Japan and 31st Linear Accelerator Meeting in Japan (CD-ROM), p.127 - 129, 2006/00
In J-PARC LINAC section, several types of beam position monitors (BPMs) from 37.7 mm to 120 mm in diameter are allocated. In this paper, background of design and key points for a larger diameter (180 mm) of BPM are reported.
Sato, Susumu; Tomisawa, Tetsuo; Akikawa, Hisashi; Ueno, Akira; Lee, S.*; Igarashi, Zenei*; Ikegami, Masanori*; Toyama, Takeshi*; Kamikubota, Norihiko*
Proceedings of 2005 Particle Accelerator Conference (PAC '05) (CD-ROM), p.2777 - 2779, 2005/00
The J-PARC LINAC requires for fine control of beam position to minimize beam loss. So that BPMs need to be calibrated with the accuracy of about a hundred micro-meters. The accuracy of BPMs are calibrated with the calibration tool and real beam. In this paper, details of these developments around BPMs are to be reported.
beam with Nd:YAG laser in J-PARCTomisawa, Tetsuo; Akikawa, Hisashi; Sato, Susumu; Ueno, Akira; Kondo, Yasuhiro; Oigawa, Hiroyuki; Sasa, Toshinobu; Hasegawa, Kazuo; Lee, S.*; Igarashi, Zenei*; et al.
Proceedings of 7th European Workshop on Beam Diagnostics and Instrumentation for Particle Accelerators (DIPAC 2005), p.275 - 277, 2005/00
The photo neutralization method with Nd:YAG laser for negative hydrogen ions has been expected as an available candidate for the transverse beam profile measurement. The fraction of photo detached electron can also be used for charge exchange procedure to extract very low power proton beam for Transmutation Experimental Facility in J-PARC. The laser system has advantages of maintenance and radiation hardness in high intensity proton accelerators. In order to establish the low power beam extraction system and beam profile monitor, the photo neutralization efficiency must be surveyed in practical beam line with high intensity H beam. In this paper, an experimental set-up and preliminary results of photo neutralization method for intense H beam in J-PARC MEBT1 are described.
