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URLhttps://doi.org/10.18429/JACoW-IPAC2025-MOPM082
TitlePhase space measurements of 90 mA and 52.5 keV H⁻ ion beam at J-PARC frontend
Authors
  • T. Shibata, Y. Sato
    Japan Proton Accelerator Research Complex, High Energy Accelerator Research Organization
  • K. Nanmo
    High Energy Accelerator Research Organization
  • K. Shinto, T. Morishita, Y. Kondo
    Japan Atomic Energy Agency
  • K. Ohkoshi, R. Kitamura
    Japan Proton Accelerator Research Complex, Japan Atomic Energy Agency
  • i. kawai
    Nihon Axis Co. Ltd.
AbstractA 90-mA and 52.5-keV negative hydrogen ion (H⁻ ion) beam has been extracted from the J-PARC Radio Frequency (RF) H⁻ ion source. The 90-mA beam phase-space distribution at the entrance of the Radio Frequency Quadrupole (RFQ) cavity was measured at the test stand. Compared with the 60-mA beam condition for the present J-PARC user operation, reasonable increase in the operation parameters (the RF input power to the ion source, the electrostatic voltage for beam extraction, and the solenoid currents for Twiss matching with the RFQ) was observed. The normalized RMS emittance increased by a few 10 %, which is within the acceptable range of the RFQ. In addition, the dependence of the beam phase-space distribution was investigated with respect to the operation parameters. Numerical analyses show that the optimum solenoid current was determined to remove the beam halo component with the orifice in the beam transport section, which was originally installed for the differential vacuum pumping of the ion source and the RFQ. In the presentation, the effect between the beam current and the phase-space distribution are discussed in aspect of the H⁻ ion beam optics.
Paperdownload: MOPM082.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
Received28 May 2025
Revised29 May 2025
Accepted30 May 2025
Issued05 November 2025
DOI10.18429/JACoW-IPAC2025-MOPM082
Pages514-516