Author: Harada, H.
Paper Title Page
MOPME020 Development of the New Measurement Method for the Incoherent Tune Spread and the Tune Shift Caused by the Space Charge Effect 512
 
  • S. Kato
    Tohoku University, Graduate School of Science, Sendai, Japan
  • H. Harada, H. Hotchi, M. Kinsho, K. Okabe
    JAEA/J-PARC, Tokai-mura, Japan
 
  For the high intensity accelerator, the incoherent tune which is the frequency of the individual particles is shifted and decreases due to the space charge effect. In addition, the incoherent tune is formed into spread shape commonly. When the incoherent tune satisfies a resonance condition, it might be occurred the beam emittance growth and the beam loss. So it is necessary to reduce the incoherent tune spread and the tune shift as much as possible. To achieve this condition, it is desired to measure the incoherent tune spread and the tune shift directly. Therefore we are developing the new measurement method of the incoherent tune spread and the shift due to the space charge effect. From the simulation results, it was cleared that the beam distribution can be modified in the case of using the mono frequency dipole exciter because a particle which has the tune corresponding to the exciter can be resonated temporary. In addition, it was cleared that it is possible to evaluate the incoherent tune spread and the tune shift by the measurement of the distribution transition. We present the outline of this method and the developing plane at the J-PARC RCS.  
 
MOPME021 Ionization Profile Monitor (IPM) of J-PARC 3-GeV RCS 515
 
  • H. Harada, K. Yamamoto
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
  • S. Kato
    Tohoku University, Graduate School of Science, Sendai, Japan
 
  Ionization profile monitors (IPM) were installed in the 3-GeV RCS ring of J-PARC and used to observe the beam-profile for the transverse plane in beam commissioning. These electrodes and MCPs of IPMs were upgraded in 2012 summer shutdown in order to improve the external electric field for leading the electrons and ions to MCPs. This presentation will be described the results of observed beam profile in beam commissioning and be discussed the new issues for the ion and electron collection mode.  
 
MOPME022 Beam Commissioning of Two Horizontal Pulse Steering Magnets for Changing Injection Painting Area from MLF to MR in the 3-GeV RCS of J-PARC 518
 
  • P.K. Saha, H. Harada, N. Hayashi, H. Hotchi, M. Kinsho, T. Takayanagi, N. Tani
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
  • Y. Irie
    KEK, Ibaraki, Japan
  • S. Kato
    Tohoku University, Graduate School of Science, Sendai, Japan
 
  We have been successfully commissioned two pulse steering magnets installed in the Linac to 3-GeV RCS (Rapid Cycling Synchrotron) injection beam transport (BT) line of J-PARC. RCS has to deliver a simultaneous as well as specific beam as demand by the downstream facilities of MLF (Material and Life Science Facility) and the MR (Main Ring). In order to obtain relatively a smaller transverse emittance at extraction, those magnets were designed to perform a smaller injection painting for the MR beam as compared to the MLF one. As stripper foil position is fixed for the charge exchange H injection, inclination of the injected beam centroid on foil for the MR beam is only moved to a smaller value by the pulse steering magnets, while DC septum magnets are fixed as determined first for the MLF beam. Their parameters were found to be very consistent with expectation and thus already in operation for switching to a painting area of 100 pi mm mrad for the MR beam as compared to that of 150 pi mm mrad for the MLF beam.  
 
MOPME023 ORBIT Beam Simulation Progress in the 3-GeV Rapid Cycling Synchrotron of J-PARC 521
 
  • P.K. Saha, H. Harada, H. Hotchi, Y. Shobuda, M. Yamamoto
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
  • J.A. Holmes
    ORNL, Oak Ridge, Tennessee, USA
  • S. Kato
    Tohoku University, Graduate School of Science, Sendai, Japan
 
  We have made a numerous progress for beam simulation in the 3-GeV RCS (Rapid Cycling Synchrotron) of J-PARC (Japan Proton Accelerator Research Complex) by using 3-D particle tracking code, ORBIT. Namely, the TEAPOT lattice file used for ORBIT tracking has been made to give exactly same results to that with SAD model used for the RCS beam commissioning. In addition, time dependent lattice functions of the injection chicane magnets and similar other time dependent lattice imperfections, which are already found to have significant influences on the beam losses in the real machine have also been successfully introduced. At present, time dependent transverse and longitudinal impedances are going to be introduced. That should prove the ORBIT code much more matured for beam simulations in synchrotrons. Latest beam simulation results illustrating these new realistic features are presented.  
 
THPWO032 Progress of Injection Energy Upgrade Project for J-PARC RCS 3833
 
  • N. Hayashi, H. Harada, K. Horino, H. Hotchi, J. Kamiya, M. Kinsho, P.K. Saha, Y. Shobuda, T. Takayanagi, N. Tani, T. Togashi, T. Ueno, M. Watanabe, Y. Watanabe, K. Yamamoto, M. Yamamoto, Y. Yamazaki, M. Yoshimoto
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
  • Y. Irie
    KEK, Ibaraki, Japan
  • T. Toyama
    J-PARC, KEK & JAEA, Ibaraki-ken, Japan
 
  The injection energy of the J-PARC RCS will be upgraded in 2013. New power supplies for the shift bump magnet system will be installed. Some of other systems, upgrade of the painting bump power supplies and pulse steering systems, are already installed and tested or used for the nominal operation. The paper reports the progress of injection energy upgrade project.  
 
THPWO033 High Intensity Beam Trial of up to 540 kW in J-PARC RCS 3836
 
  • H. Hotchi, H. Harada, N. Hayashi, M. Kinsho, P.K. Saha, Y. Shobuda, F. Tamura, K. Yamamoto, M. Yamamoto, M. Yoshimoto
    JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
  • Y. Irie
    KEK, Ibaraki, Japan
  • S. Kato
    Tohoku University, Graduate School of Science, Sendai, Japan
 
  Recently we have performed a high intensity beam trial of up to 540 kW. In this paper, beam intensity dependece and injection painting parameter dependence of beam loss, observed in this beam experiment, will be discussed with the corresponding numerical simulation results.