IPAC2014 - List of Authors (Ezura, E.)

Paper	Title	Page
TUPRI023	Simulation of Debunching for Slow Extraction in J-PARC MR	1606
	M. Yamamoto, M. Nomura, T. Shimada, F. Tamura JAEA/J-PARC, Tokai-mura, Japan E. Ezura, K. Hara, K. Hasegawa, C. Ohmori, A. Takagi, K. Takata, M. Toda, M. Yoshii KEK, Tokai, Ibaraki, Japan A. Schnase GSI, Darmstadt, Germany
	The J-PARC MR delivers a proton beam for nuclear physics experiments with slow extraction. The beam is debunched at flat top to obtain a coasting beam by turning off the rf voltage. The controlled emittance blow-up before the flat top has been investigated to mitigate the microwave instability. Beam loading effect can disturb the uniformity of the debunching at the flat top. We describe the results of the particle tracking simulation whole acceleration cycle including the controlled emittance blow-up and the beam loading effect.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI023
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THPME062	Status of the J-PARC Ring RF Systems	3376
	M. Yoshii, M. Nomura, T. Shimada, F. Tamura, M. Yamamoto KEK/JAEA, Ibaraki-Ken, Japan E. Ezura, K. Hara, K. Hasegawa, C. Ohmori, K. Takata, M. Toda KEK, Tokai, Ibaraki, Japan A. Schnase GSI, Darmstadt, Germany
	The high intensity proton accelerator complex (J-PARC) consists of the Linac, the 25Hz rapid cycling synchrotron (RCS) and the 50GeV main synchrotron (MR). During the long shutdown of 2013, the Linac energy was upgraded from 181MeV to the design value of 400MeV. In the RCS, we have installed the last 12th RF system. In operation from January 2014, beam commissioning aimed at 1 MW operation will be started. In the MR, the upgrade plan of the beam power, realizing by raising the repetition, has been started. For this reason the accelerating voltage must be increased, and all MR RF systems will be replaced with more efficient systems. A new magnetic alloy material (FT3L) has been developed. Manufacturing of the FT3L accelerating cavities has proceeded. It becomes possible to increase the accelerating voltage from 280 kV to 540 kV, using the new cavities in combination with the existing RF power supplies. We have started the developments of a 2nd harmonic system loaded with air-cooled FT3L cores and a high-Q VHF cavity system, too. Both systems are used for longitudinal dilution increase the bunching factor of the circulating high intensity proton beam.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME062
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Simulation of Debunching for Slow Extraction in J-PARC MR

1606

M. Yamamoto, M. Nomura, T. Shimada, F. Tamura
JAEA/J-PARC, Tokai-mura, Japan
E. Ezura, K. Hara, K. Hasegawa, C. Ohmori, A. Takagi, K. Takata, M. Toda, M. Yoshii
KEK, Tokai, Ibaraki, Japan
A. Schnase
GSI, Darmstadt, Germany

The J-PARC MR delivers a proton beam for nuclear physics experiments with slow extraction. The beam is debunched at flat top to obtain a coasting beam by turning off the rf voltage. The controlled emittance blow-up before the flat top has been investigated to mitigate the microwave instability. Beam loading effect can disturb the uniformity of the debunching at the flat top. We describe the results of the particle tracking simulation whole acceleration cycle including the controlled emittance blow-up and the beam loading effect.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-TUPRI023

Export •

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

THPME062

Status of the J-PARC Ring RF Systems

3376

M. Yoshii, M. Nomura, T. Shimada, F. Tamura, M. Yamamoto
KEK/JAEA, Ibaraki-Ken, Japan
E. Ezura, K. Hara, K. Hasegawa, C. Ohmori, K. Takata, M. Toda
KEK, Tokai, Ibaraki, Japan
A. Schnase
GSI, Darmstadt, Germany

The high intensity proton accelerator complex (J-PARC) consists of the Linac, the 25Hz rapid cycling synchrotron (RCS) and the 50GeV main synchrotron (MR). During the long shutdown of 2013, the Linac energy was upgraded from 181MeV to the design value of 400MeV. In the RCS, we have installed the last 12th RF system. In operation from January 2014, beam commissioning aimed at 1 MW operation will be started. In the MR, the upgrade plan of the beam power, realizing by raising the repetition, has been started. For this reason the accelerating voltage must be increased, and all MR RF systems will be replaced with more efficient systems. A new magnetic alloy material (FT3L) has been developed. Manufacturing of the FT3L accelerating cavities has proceeded. It becomes possible to increase the accelerating voltage from 280 kV to 540 kV, using the new cavities in combination with the existing RF power supplies. We have started the developments of a 2nd harmonic system loaded with air-cooled FT3L cores and a high-Q VHF cavity system, too. Both systems are used for longitudinal dilution increase the bunching factor of the circulating high intensity proton beam.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME062

Export •

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