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URLhttps://doi.org/10.18429/JACoW-IPAC2025-TUPB031
TitleOverview of seven-unit collimator system and its operation for J-PARC main ring
Authors
  • M. Shirakata, T. Yasui, K. Kadowaki
    High Energy Accelerator Research Organization
  • Y. Sato, J. Takano
    Japan Proton Accelerator Research Complex
  • M. Nishikawa
    Japan Proton Accelerator Research Complex, Nippon Advanced Technology Co., Ltd.
AbstractThe J-PARC main ring has three linear sections, and one have a beam collimator system downstream of the injection devices to localise beam losses. In September 2024, the seventh collimator unit was installed, completing an upgrade of the collimator system that has been underway since 2012. The system was changed from one that scatters and captures the beam halo to one that draws the jaw close to the beam core and directly removes its halo. This allowed a number of collimator units to be placed in a limited area. The original beam loss capacity in the collimator area was 450 W. Seven collimator units allow a beam loss of 3.5 kW. Currently, six collimator units are used to deliver 800 kW beams to neutrino experiments with losses of less than 500 W. By using seven collimator units, a beam of 1.3 MW can be delivered with a reasonable loss amount. The combination of units effectively removes the halo component of the beam and localises the beam losses. However, the direct removal method can create loss spots downstream of the collimator according to phase advance. This paper describes the operation of collimators in actual beam operation.
Paperdownload: TUPB031.pdf
CiteBibTeX, LaTeX, Text/Word, RIS, EndNote
Conference16th International Particle Accelerator Conference
Series
LocationTaipei, Taiwan
Date01-06 Jun 2025
PublisherJACoW Publishing, Geneva, Switzerland
Editorial Board* Ming-Chyuan Lin - National Synchrotron Radiation Research Center * Yoichi Sato - KEK * Jui-Che Huang - National Synchrotron Radiation Research Center * David Button - Australian Nuclear Science and Technology Organisation * Ping-Shun Chuang - National Synchrotron Radiation Research Center
Online ISBN978-3-95450-248-6
Online ISSN2673-5490
Received29 May 2025
Revised30 May 2025
Accepted30 May 2025
Issued05 November 2025
DOI10.18429/JACoW-IPAC2025-TUPB031
Pages1037-1039