IBIC2017 - List of Authors (Yoshii, M.)

Paper	Title	Page
TUPCF10	Measurement of the Longitudinal Coupled Bunch Instabilities in the J-PARC Main Ring	225
	Y. Sugiyama, M. Yoshii KEK, Tokai, Ibaraki, Japan F. Tamura JAEA/J-PARC, Tokai-mura, Japan
	J-PARC Main Ring (MR) is a high intensity proton synchrotron which accelerates protons from 3 GeV to 30 GeV. Its beam power for fast extraction reached 470 kW, which corresponds to 2.4x10¹⁴ proton per pulse, in February, 2017 and the studies to reach higher beam intensity are in progress. We observed longitudinal dipole coupled bunch instabilities in the MR for beam power beyond 470 kW. To investigate the source of the instabilities and to mitigate them, we have identified the modes of the longitudinal dipole coupled bunch oscillation and measured their growth during the acceleration cycle using the beam signals. The identification and the measurement were done with two different methods which use the motion of bunch centers and the frequency spectrum around the harmonics of the revolution frequency. At the conference, we will report the method and the result of the measurement of the longitudinal coupled bunch instabilities in the J-PARC MR.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2017-TUPCF10
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Paper

Title

Page

Measurement of the Longitudinal Coupled Bunch Instabilities in the J-PARC Main Ring

225

Y. Sugiyama, M. Yoshii
KEK, Tokai, Ibaraki, Japan
F. Tamura
JAEA/J-PARC, Tokai-mura, Japan

J-PARC Main Ring (MR) is a high intensity proton synchrotron which accelerates protons from 3 GeV to 30 GeV. Its beam power for fast extraction reached 470 kW, which corresponds to 2.4x10¹⁴ proton per pulse, in February, 2017 and the studies to reach higher beam intensity are in progress. We observed longitudinal dipole coupled bunch instabilities in the MR for beam power beyond 470 kW. To investigate the source of the instabilities and to mitigate them, we have identified the modes of the longitudinal dipole coupled bunch oscillation and measured their growth during the acceleration cycle using the beam signals. The identification and the measurement were done with two different methods which use the motion of bunch centers and the frequency spectrum around the harmonics of the revolution frequency. At the conference, we will report the method and the result of the measurement of the longitudinal coupled bunch instabilities in the J-PARC MR.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2017-TUPCF10

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)