KEK, Ibaraki
JAEA/LINAC, Ibaraki-ken
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
The output energy of J-PARC linac is planned to be upgraded from 190 MeV to 400 MeV by adding an ACS (Annular Coupled Structure linac) section. The ACS is a variety of coupled-cavity structure linac newly devised for former JHP (Japan Hadron Project), and its original beam dynamics design for J-PARC was presented in LINAC02 [M. Ikegami et. al., in Procs. of LINAC02, p. 629]. Extensive R&D studies have been conducted since then to establish the feasibility of ACS, where four ACS modules have been fabricated and successfully high-power tested. In parallel, the beam dynamics design of the ACS has been further optimized to reflect the experience obtained in the R&D studies and reduce the cost for mass production. In this paper, the revised beam dynamics design of the J-PARC ACS is presented with some simulation results with a particle simulation code.
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
LASTI, Hyogo
Hiroshima University, Graduate School of Science, Higashi-Hiroshima
KEK, Ibaraki
J-PARC, KEK & JAEA, Ibaraki-ken
The beam commissioning of the J-PARC 3-GeV RCS started in October 2007. The initial machine parameter tuning and underlying beam studies were completed in February 2008 through various beam dynamics measurements, such as optical functions, turn-by-turn beam positions, and transverse and logitudinal beam profiles. Now the RCS is in transition from the first commissioning phase to the next challenging stage and our efforts hereafter will be focused on higher beam power operations. In this paper, we describe experimental results obtained in the high intensity demonstrations in October 2008, together with the corresponding simulation results.
J-PARC, KEK & JAEA, Ibaraki-ken
The Japan Proton Accelerator Research Complex (J-PARC) is a multi-purpose facility making full use of secondary particles like neutrons, muons, Kaons, and neutrinos produced by the MW-class proton accelerators. The J-PARC accelerator scheme inserts a 3-GeV Rapid-Cycling Synchrotron (RCS) in between a 400-MeV injector linac (at present 181 MeV) and a several-ten GeV Main Ring (MR). The RCS has already demonstrated extraction of one pulse of 2.6·1013 protons at 3 GeV, which corresponds to 315 kW if operated at 25 Hz, with a beam loss less than one percent, and a beam power of 210 kW for a period of 70 sec in September. The beam circulation and RF capture in MR have been done in May. Also, the neutron production target was beam-commissioned, providing high-resolution, high-efficiency neutrons. The RCS users’ run and the 30-GeV MR acceleration are planned in December. Rationale for the J-PARC accelerator scheme will be resumed on the basis of the results and difficulties encountered during the development, the construction and the commissioning. The upgrade plan, and, hopefully, some experimental results will be presented.
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
LASTI, Hyogo
Hiroshima University, Graduate School of Science, Higashi-Hiroshima
KEK, Ibaraki
J-PARC, KEK & JAEA, Ibaraki-ken
The beam commissioning of the J-PARC 3-GeV RCS started in October 2007. The initial machine parameter tuning and underlying beam studies were completed in February 2008 through various beam dynamics measurements, such as optical functions, turn-by-turn beam positions, and transverse and logitudinal beam profiles. Now the RCS is in transition from the first commissioning phase to the next challenging stage and our efforts hereafter will be focused on higher beam power operations. In this paper, we describe experimental results obtained in the high intensity demonstrations in October 2008, together with the corresponding simulation results.