Author: Hayashi, N.
Paper Title Page
WEOAA03 Development of the Beam Halo Monitor in the J-PARC 3-GeV RCS 2122
 
  • M. Yoshimoto, N. Hayashi, H. Hotchi, M. Kinsho, S.I. Meigo, K. Okabe, P.K. Saha, K. Yamamoto
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
 
  Transverse beam halo is one of the most important beam parameters due to limit the performance of the high intensity beam accelerator. Therefore the transverse beam halo measurement is required to increase the beam power of the J-PARC 3-GeV RCS. Transverse halo monitors, which are horizontal and vertical scanning aluminum plates type, has been installed in the extraction beam line. But the residual secondary electrons hindered the beam halo diagnostic. Thus we develop the new beam halo monitor with vibrating wire monitor.  
slides icon Slides WEOAA03 [6.701 MB]  
 
THPPD051 New Power Supply of the Injection Bump Magnet for Upgrading the Injection Energy in the J-PARC 3-GeV RCS 3626
 
  • T. Takayanagi, N. Hayashi, M. Kinsho, N. Tani, T. Togashi, T. Ueno
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
 
  With the energy upgrading of LINAC (Linear accelerator) to 400 MeV in the J-PARC (Japan Proton Accelerator Research Complex), a new power supply of the injection bump magnet has been designed for the 3-GeV RCS (Rapid Cycling Synchrotron). The new power supply is composed with the capacitor bank which has function to form the output current pattern. This power supply is a commutation strategy using the electrical charge and discharge of the capacitor, and the frequency of the switch that becomes the source of the noise is a little. Comparing to the conventional switching-type power supply, this power supply is switched only twice for the pattern formation. Thus, the ripple due to the switching can be expected to be much lower. The 1/16 scale model was manufactured and the characteristics was evaluated. This paper summarizes the design parameter and the experimental result of the new power supply.  
 
THPPD052 Operation and Current Status of Injection, Extraction, Kicker Magnet and the Power Supply for J-PARC 3 GeV RCS 3629
 
  • M. Watanabe, N. Hayashi, Y. Shobuda, K. Suganuma, T. Takayanagi, T. Togashi
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
  • T. Toyama
    J-PARC, KEK & JAEA, Ibaraki-ken, Japan
 
  3-GeV RCS (Rapid Cycling Synchrotron) at High Intensity Proton Accelerator Facility (J-PARC) have started for 24-hour operation with repetition rate of 25 pps in February, 2009. Kicker power supply system which uses thyratrons switches is used for extraction of the proton beam. There were many troubles for unstable operation of the thyratrons just after beam commissioning started. Recently, however, the operations were improved and the failure rate was reduced to approximately 0.1 % in October 2010. After the earthquake on March 11, 2011, the injection and extraction magnets, power supplies, the cables and the bus-duct have been checked. Insulation resistance test, impedance test were performed. Reflected wave measurements by the low-level and high-power pulse of the kicker magnets were performed. Visual checks by a fiber endoscope were also performed in the kicker magnets. The results of the measurements and the checks were all not in the problem.  
 
THPPP070 Comparison of the Residual Doses Before and After Resumption of User Operation in J-PARC RCS 3901
 
  • K. Yamamoto, H. Harada, S. Hatakeyama, N. Hayashi, H. Hotchi, M. Kinsho, R. Saeki, P.K. Saha, M. Yoshimoto
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
 
  J-PARC Facilities were damaged by East Japan Earthquake in March 2011, but All Facirities resumed a beam operation from December 2012. In this paper, we report and compare the beam loss distribution and the residual doses before and after resumption of user operation in J-PARC RCS.  
 
THPPP081 Status of Injection Energy Upgrade for J-PARC RCS 3921
 
  • N. Hayashi, H. Harada, H. Hotchi, J. Kamiya, P.K. Saha, Y. Shobuda, T. Takayanagi, N. Tani, M. Watanabe, Y. Watanabe, K. Yamamoto, M. Yamamoto, Y. Yamazaki, M. Yoshimoto
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
  • T. Toyama
    J-PARC, KEK & JAEA, Ibaraki-ken, Japan
 
  The injection energy upgrade for J-PARC RCS is planed in 2013. This includes the power supplies upgrade of injection pulsed magnet system, suppression for leakage field, quadrupole correction magnets, reduction of kicker impedance effect and improvements of beam diagnostic instrumentation. The paper reports the present status.