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Miyawaki, Nobumasa; Fukuda, Mitsuhiro*; Kurashima, Satoshi; Kashiwagi, Hirotsugu; Okumura, Susumu; Arakawa, Kazuo*; Kamiya, Tomihiro
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.500 - 502, 2014/06
no abstracts in English
Fukuta, Shimpei; Sawabe, Yuki; Suzuki, Takahiro*; Ishiyama, Tatsuya*; Kawase, Masato*; Ito, Yuichi; Kato, Yuko; Yoshii, Akinobu; Kikuzawa, Nobuhiro; Ouchi, Nobuo
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1122 - 1125, 2014/06
The installation of Cs-seeded RF-driven H
ion source (RF ion source) to J-PARC LINAC is scheduled in 2014. Similarly the replacement of RFQ III from RFQ is scheduled in 2014. The test stand of the cooperation of RF ion source & RFQ III is being made in the J-PARC LINAC building for the beam acceleration examination now. The J-PARC control group designed test stand control system by thinking that test stand control system had to be equal to J-PARC accelerator control system. Specifically, Introduction of MPS for protect an apparatus. Implementation of EPICS environment for remotely controlling the equipment. It is construction of the timing system for sending a timing signal to each accelerator component device. This report describes construction of the control system in a test stand.
Sawamura, Masaru; Nagai, Ryoji; Nishimori, Nobuyuki; Hajima, Ryoichi
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.956 - 959, 2014/06
no abstracts in English
Miura, Akihiko; Feschenko, A. V.*; Mirzojan, A. N.*; Miyao, Tomoaki*; Ouchi, Nobuo; Oguri, Hidetomo; Hasegawa, Kazuo; Ikegami, Masanori*
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.705 - 708, 2014/06
In J-PARC linac, a project for energy and intensity upgrade has been progressed since 2009 using Annular-ring Coupled Structure (ACS) cavities. Because the longitudinal matching of the injection beam to the ACS cavities is required as well as the transverse matching, we decided to employ the bunch shape monitors (BSM's) to measure the longitudinal beam profile. We developed three BSM's in collaboration with INR (Institute for Nuclear Research: Russia) for the upstream part of the ACS section. We introduce the structure of BSM and mention the measured results taken during the commissioning of BSM.
Miyao, Tomoaki*; Miura, Akihiko; Kondo, Yasuhiro; Morishita, Takatoshi; Sugimura, Takashi*; Ouchi, Nobuo; Oguri, Hidetomo; Maruta, Tomofumi*; Naito, Fujio
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1049 - 1052, 2014/06
In J-PARC linac, a project for energy and intensity upgrade has been progressed using 50 mA RFQ(Radio-Frequency-Quadrupole) linac cavity. Because the RFQ had already fabricated, test stand for its performance test was newly produced. In the test stand, we designed and fabricated the monitoring system including beam current monitors for the beam transmission measurement and the beam phase monitors for the energy measurement. We will refer the detail of the monitoring system and the data obtained during the performance test. New testing devices are also mentioned.
Nomura, Masahiro; Yamamoto, Masanobu; Shimada, Taihei; Tamura, Fumihiko; Omori, Chihiro*; Toda, Makoto*; Hasegawa, Katsushi*; Hara, Keigo*; Yoshii, Masahito*; Schnase, A.*
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.217 - 220, 2014/06
J-PARC RCS and MR employ RF cavities loaded with Magnetic Alloy (MA) cores. To achieve the high shunt impedance, we measured the shunt impedance with changing the core filling factor, ribbon thickness, and magnetization process. The shunt impedance was reduced in despite of the filling factor increase because the strong winding tension deteriorate the magnetic property. The MA core with thin ribbons and the MA core that is magnetized by a rotation process show high permeability in the accelerating frequency region, and those MA cores show the high shunt impedance consequently.
Okoshi, Kiyonori; Ikegami, Kiyoshi*; Koizumi, Isao; Ueno, Akira; Takagi, Akira*; Yamazaki, Saishun; Oguri, Hidetomo
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.946 - 949, 2014/06
A J-PARC ion source driven with a LaB6 filament is being operated without any serious trouble since the restoration from the earthquake. The H ion current from the source is routinely restricted 19 mA for the filament lifetime. In order to increase the beam power at the linac beam operation, the beam current from the ion source was increased to 22 mA. At this operation, the filament lifetime was estimated by the reduction in the filament current. According to the steep reduction in the filament current, the break of the filament was predicted. Although the filament has broken after 10 h from the steep current reduction, the beam operation was restarted 8 h later by the preparation for the exchange of new filament. At the study time for the 3 GeV synchrotron, the ion source was operated at 30 mA for 8 days.
Jimbo, Koichi*; Soda, Hikaru*; Nakao, Masao*; Yuri, Yosuke; Tongu, Hiromu*; Noda, Akira*
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1057 - 1059, 2014/06
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.
Takahashi, Hiroki; Kojima, Toshiyuki; Narita, Takahiro; Maebara, Sunao; Sakaki, Hironao; Suzuki, Hiromitsu
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.724 - 727, 2014/06
no abstracts in English
Yamamoto, Kazami; Hayashi, Naoki; Hatakeyama, Shuichiro; Saeki, Riuji; Iwama, Yuhei
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1060 - 1064, 2014/06
The 3 GeV Rapid Cycling Synchrotron (RCS) of the Japan Proton AcceleratoR Complex (J-PARC) provides more than 300 kW beam to the Material and Life Science Facility (MLF) and the Main Ring (MR). In such high intensity hadron accelerator, the lost protons that are a fraction of the beam less than 0.1% cause many problems. Those particles bring about a serious radioactivation and a malfunction of the accelerator components. Therefore, the beam loss monitor (BLM) is one of the most important equipment to observe the state of the beam during operation, and to keep a steady operation. Moreover, if we set operation parameters of BLM adequately, it can detect the beam loss that is 10
fraction of the beam. Thus it enables fine-tuning of the accelerator. In the J-PARC RCS, a proportional counter and a plastic scintillation counter are used for the beam commission and the stable operation as BLM. We report present status of the BLM system in J-PARC RCS.
Noda, Akira*; Nakao, Masao*; Soda, Hikaru*; Tongu, Hiromu*; Okamoto, Hiromi*; Osaki, Kazuya*; Yuri, Yosuke; Jimbo, Koichi*; Grieser, M.*; He, Z.*
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.143 - 145, 2014/06
ion source for the J-PARCKoizumi, Isao; Ueno, Akira; Okoshi, Kiyonori; Ikegami, Kiyoshi*; Takagi, Akira*; Yamazaki, Saishun; Oguri, Hidetomo
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.920 - 923, 2014/06
In order to satisfy the J-PARC (Japan Proton Accelerator Research Complex) 2nd stage requirements the J-PARC rf-driven H ion source is under development. The source plasma is produced by an about 50 W CW 30 MHz-rf and an about 40 kW pulsed 2 MHz-rf. The Cs is installed into the plasma chamber by opening the Cs-valve between the plasma chamber and the Cs oven, which is heated to 200
240 
C. The H ion beam current is maximized by optimizing the Cs quantity depending upon the Cs-valve opening time, the PE temperature depending upon the flow rate of the air through the PE cooling plate, the AMFC by the AMFC coil current, and so on. The experimental results using the plasma chamber made of copper, which satisfied the above requirements, were reported last year. The experimental results using the plasma chamber made of stainless steel are presented in this paper. The observed several interesting differences between the two plasma chambers are also presented.
Kikuzawa, Nobuhiro; Yoshii, Akinobu; Ikeda, Hiroshi; Kato, Yuko
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.230 - 234, 2014/06
J-PARC is consists of much equipment. In Linac and 3GeV synchrotron, the data of over the 64,000 EPICS records for these apparatus control is being collected. The data has been being stored by a RDB system using PostgreSQL now, but it is not enough in availability, performance, and extendibility. Therefore, the new system architecture is required, which is rich in the pliability and can respond to the data increasing continuously for years to come. In order to cope with this problem, we considered adoption of the distributed database architecture and constructed the demonstration system using HBase. We present results of these demonstration.
Kawase, Masato*; Takahashi, Hiroki; Kato, Yuko; Kikuzawa, Nobuhiro; Ouchi, Nobuo
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.731 - 734, 2014/06
The data acquisition in J-PARC LINAC/RCS are two methods of data archiving of polling data via EPICS Channel Access and synchronized waveform data. The synchronized waveform data are collected by several Wave Endless Recorders (WER). The WER counts the trigger number and holds waveform data in a ring buffer memory. We developed a Trigger Counter in order to manage the trigger number of each WER and synchronize the trigger number of each WER via LAN. At present, in order to install the waveform data synchronization system, we carried out verification using the timing test bench. This report presents about the waveform data synchronization system and future plan of the data acquisition system.
Yuri, Yosuke; Yuyama, Takahiro; Ishizaka, Tomohisa; Yoshida, Kenichi; Ishibori, Ikuo; Okumura, Susumu
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.138 - 142, 2014/06
no abstracts in English
Hirano, Koichiro; Ito, Takashi; Kondo, Yasuhiro; Shinozaki, Shinichi; Chishiro, Etsuji; Miura, Akihiko; Morishita, Takatoshi; Ikegami, Masanori*; Kubota, Chikashi*; Sugimura, Takashi*; et al.
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.858 - 861, 2014/06
Two RF-deflecting cavities as a chopper and a beam scraper have been used in the MEBT between a 324 MHz RFQ and a 50-MeV DTL of the J-PARC Linac. We plan to increase a peak beam current up to 50 mA by replacing an ion source and a RFQ after the summer shutdown in 2014. Beam loss occurs in the RF chopper for the 50 mA operation. Moreover, the beam scraper cannot fully stand the beam load with 50 mA, 0.5 ms, 3 MeV, and 25 Hz. We have studied the new RF chopper cavity by using HFSS code and the tandem scraper system with two scrapers.
Tamura, Fumihiko; Yamamoto, Masanobu; Omori, Chihiro*; Yoshii, Masahito*; Schnase, A.*; Nomura, Masahiro; Tomizawa, Masahito*
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.125 - 129, 2014/06
For the slow extraction in the J-PARC MR, the rf voltage ins the cavities is turned off after finishing the acceleration to obtain a coasting beam. During the debunching process, the average momentum decrease due to the longitudinal coupling impedances in the MR. The decelatation continues until a well debunchedbeam is foarmed. The deceraration causes a reduction of the extraction efficiency due to the chromatic effects. In the J-PARC MR, a momentum loss has been observed at a relatively low beam power. To achieve higher beam power with keeping the high extraction efficiency, measures against the momentum loss are necessary. In this article, we report the observations and simulation results of the momentum losses. We adopt the rf feedforward method to cancel the wake voltage in the cavity as a measure of the momentum loss. By the feedforward, the momentum loss is significantly reduced. We achieve a high extraction efficiency, 99.5%, at the beam power of 20 kW.
Oguri, Hidetomo
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.313 - 317, 2014/06
no abstracts in English
