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Yoshimoto, Masahiro; Harada, Hiroyuki; Okabe, Kota; Kinsho, Michikazu
Proceedings of 4th International Beam Instrumentation Conference (IBIC 2015) (Internet), p.575 - 579, 2016/01
In the J-PARC RCS, transverse beam profiles including both the beam core and halo at extraction beam transport line (3NBT) were measured by using a combination with a wire scanner type beam scraper and some beam loss monitors (BLMs). Our final goal of this halo monitor is to measure the intra-bunch beam halo of extracted two bunches from the RCS. Thus the plastic scintillator and photomultiplier (PMT) assemblages were adopted as the BLMs with quick time response. However, we found that the BLMs detected not only the radiation from the wire but also reflected one from other devices and wall. Therefore we tried to develop new-type BLMs, which are scintillation-type BLM of lead glass and Cherenkov-type BLM of quartz or UV acrylic. In this presentation, we will report on the overview and experimental results of the new-type BLMs together with the outline of halo monitor system.
Yoshimoto, Masahiro; Harada, Hiroyuki; Hotchi, Hideaki; Saha, P. K.; Tamura, Fumihiko; Yamamoto, Masanobu; Kinsho, Michikazu
Proceedings of 6th International Particle Accelerator Conference (IPAC '15) (Internet), p.944 - 946, 2015/06
In the J-PARC RCS, the beam tuning toward the design output beam power of 1MW were started after the completing of the beam energy and beam current upgrades in the LINAC. One of the important issues to achieve the 1MW beam operation is the optimization of the injection beam from the LINAC. Due to the longitudinal beam tuning in the LINAC, the momentum spread of the injected beam into the RCS was measured with the longitudinal tomography method. Our longitudinal tomography tool had been developed using the simple algorithm with the Convolution Back Projection (CBP) method for the beam storage mode of the RCS. Accordingly, we improved this tool to expand into the acceleration mode. By tuning the tank level of the debuncher 2 in the LINAC, it can be measured the momentum spread was shifted from 0.06% to 0.15%. Moreover, these distributions of the momentum spread are consistent with the simulation results.
Hayashi, Naoki; Hiroki, Seiji; Kishiro, Junichi*; Teruyama, Yuzo*; Toyokawa, Ryoji; Arakawa, Dai*; Lee, S.*; Miura, Takako*; Toyama, Takeshi*
Proceedings of 2005 Particle Accelerator Conference (PAC '05) (CD-ROM), p.299 - 301, 2005/00
Development of the beam diagnostics system for the J-PARC (Japan Proton Accelerator Research Complex) Rapid-Cycling Synchrotron is described. The system consists of Beam Position Monitor (BPM), Beam Loss Monitor (BLM), Current monitors (DCCT, SCT, MCT, FCT, WCM), Tune meter system, 324MHz-BPM, Profile monitor, and Halo monitor. BPM electrode is electro-static type and its electronics is designed for both COD and turn-by-turn measurements. Five current monitors have different time constants in order to cover wide frequency range. The tune meter is consisted of RFKO and the beam pick-up electrode. For the continuous injected beam monitoring, 324MHz-BPM detects Linac frequency. Two types of profile monitor are multi-wire for low intensity tuning and the residual gas monitor for non-destructive measurement.
Tomisawa, Tetsuo; Kishiro, Junichi; Hiroki, Fumio; Sato, Susumu; Igarashi, Zenei*; Lee, S.*; Nigorikawa, Kazuyuki*; Toyama, Takeshi*
Proceedings of 1st Annual Meeting of Particle Accelerator Society of Japan and 29th Linear Accelerator Meeting in Japan, p.165 - 167, 2004/08
It proceeds with the beam monitor production of the beam diagnosis system with J-PARC. In this paper, the present status of beam position monitors (BPM) for the SDTL is described. The impedance of strip line monitor have been adjusted in the construction of housing and electrodes of the BPM. The 4-stripline BPM has already been examined in the medium energy beam transport (MEBT) line. Preliminary results of beam position measurement for various beam conditions are reported.
Tomisawa, Tetsuo; Kishiro, Junichi; Igarashi, Zenei*; Lee, S.*; Hiroki, Fumio
Proceedings of 28th Linear Accelerator Meeting in Japan, p.428 - 430, 2003/08
It is an important factor whether to have a beam loss held how, and the part of the beam diagnosis is important with the accurate beam transport, the occurrence of the high quality beam to accelerate a high intensity proton beam to handle with J-PARC linac accelerator safely. It responds to the purpose, and the beam monitor used for this beam diagnosis has it variously. There are an electric current monitor, a phase monitor, a beam position monitor, a profile monitor, a beam size monitor, a screen monitor, a beam loss monitor, and so on. Report it about these beam monitors in the present condition.
Hanashima, Susumu
JAERI-Conf 2000-019, P. 109, 2001/02
no abstracts in English
Okumura, Susumu; Fukuda, Mitsuhiro; Yokota, Wataru; Nakamura, Yoshiteru; Nara, Takayuki; Agematsu, Takashi; Ishibori, Ikuo; Arakawa, Kazuo
Proc. of the 4th European Particle Accelerator Conf. Vol. 2; EPAC94, 0, p.1518 - 1520, 1994/00
no abstracts in English
; Shibata, Michihiro; Ishii, Tetsuro;
Proc. of the 9th Symp. on Accelerator Science and Technology, p.437 - 439, 1993/00
no abstracts in English
Sakaki, Hironao; Nishiuchi, Mamiko; Dover, N.*; Fukuda, Yuji; Nishitani, Keita*; Kon, Akira; Hayakawa, Takehito; Shizuma, Toshiyuki; Kin, Tadahiro*; Watanabe, Yukinobu; et al.
no journal, ,
We will discuss the upgrade project of J-KAREN-P laser system. In particular, we are going to speak about diagnostics system for ion-beam.
Hayashi, Naoki
no journal, ,
In order to realize stable accelerator operation, it is necessary to understand various interlocked events and take countermeasures. In the J-PARC Linac, many interlocked events which include waveform data of current monitors and beam loss monitors, were recorded and classified to the various pattern. Their counter measures are under consideration. In the RCS (Rapid-Cycling Synchrotron), new processing unit is prepared to record beam current and position date of interlocked event and its future perspective will be reported.
