A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z  

Naito, F.

Paper Title Page
MOP004 Operating Experience of the J-PARC Linac 55
  • K. Hasegawa, H. Asano, T. Ito, T. Kobayashi, Y. Kondo, H. Oguri, A. Ueno
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
  • S. Anami, Z. Fang, Y. Fukui, K. Ikegami, M. Kawamura, F. Naito, K. Nanmo, H. Tanaka, S. Yamaguchi
    KEK, Ibaraki
  • E. Chishiro, T. Hori, H. Suzuki, M. Yamazaki
    JAEA, Ibaraki-ken
  • Y. Namekawa, K. Ohkoshi
    J-PARC, KEK & JAEA, Ibaraki-ken

The J-PARC (Japan Proton Accelerator Research Complex) linac consists of an RFQ, a Drift Tube Linac and a Separated-type Drift Tube Linac. The beam commissioning of the linac started in November 2006 and 181 MeV acceleration was successfully achieved in January 2007. The linac has delivered beams to the 3 GeV Rapid Cycling Synchrotron for its commissioning, and then, the subsequent 50 GeV Main Ring Synchrotron and the neutron target commissioning. The linac uses 20 units of 324 MHz klystrons. As of May, 2008, the average number of filament hours exceeds 5,000 without serious troubles. The operating experience of the linac will be described in this paper.

THP056 Improvement in the ACS Cavity Design for the J-PARC Linac Energy Upgrade 915
  • H. Ao, K. Hasegawa, K. Hirano, T. Morishita, A. Ueno
    JAEA/LINAC, Ibaraki-ken
  • H. Asano
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
  • M. Ikegami, F. Naito
    KEK, Ibaraki
  • V.V. Paramonov
    RAS/INR, Moscow
  • Y. Yamazaki
    J-PARC, KEK & JAEA, Ibaraki-ken

The ACS (Annular-ring Coupled Structure) cavities were under development for the J-PARC Linac from 190 MeV to 400 MeV. We have fixed the cavity specification, taking into account the results of the high-power conditioning and the fabrication experience. The mass production of the ACS with a tight time schedule is now an issue, since the user community strongly requests the beam power upgrade as early as possible. Therefore, the design and the fabrication process of the ACS cavity have been reexamined on the basis of the experience, stored during the course of the fabrication and the tuning of the prototype ACS tanks. Here, we also discussed about the key issues on the mass production with a manufacturer. The cavity shape, that required complicated machining, was simplified to some extent, while the frequency tuning strategy was reconsidered to reduce the production period. The paper describes these recent activities on the ACS development.