Author: Asano, H.
Paper Title Page
THPWO036 Annular-Ring Coupled Structure Linac for the J-PARC Linac Energy Upgrade 3845
  • H. Ao, H. Asano, Y. Nemoto, N. Ouchi, J. Tamura
    JAEA/J-PARC, Tokai-mura, Japan
  • F. Naito, K. Takata
    KEK, Ibaraki, Japan
  The linac of Japan Proton Accelerator Research Complex (J-PARC) is the injector to the 3-GeV rapid cycle synchrotron. In order to increase the beam power of the synchrotron, the task of the 400-MeV energy upgrade of the linac started from March 2009. Following the 191-MeV Separated-type DTL, the 25 modules of the Annular-ring Coupled Structure (ACS) linac will be added from August 2013. The operating frequency and the accelerating field E0 of the ACS are 972 MHz and 4.2 MV/m, respectively. The cavity fabrication of the ACS has been almost finished, and then the completed cavities are stored in the J-PARC site. Currently, pumps and vacuum components are being installed on the cavities for the test of vacuum condition. For the pulsed beam of J-PARC, the vacuum pressure have to be less than 10-6 Pa in order not to exceed 0.1 W/m beam loss. In this paper, we present the R&D results to reduce the vacuum pressure using the stored ACS cavity and the current status of the energy upgrade.