Paper |
Title |
Page |
THDC1 |
Slow Extraction Operation at J-PARC Main Ring |
219 |
|
- M. Tomizawa, Y. Arakaki, T. Kimura, S. Murasugi, R. Muto, H. Nishiguchi, K. Okamura, Y. Shirakabe, Y. Sugiyama, E. Yanaoka, M. Yoshii
KEK, Ibaraki, Japan
- K. Noguchi
Kyushu University, Fukuoka, Japan
- F. Tamura
JAEA/J-PARC, Tokai-mura, Japan
|
|
|
A high-intensity proton beam accelerated in the J-PARC main ring (MR) is slowly extracted by using the third integer resonance and delivered to the experimental hall. A critical issue in slow extraction (SX) is a beam loss caused during the extraction. A dynamic bump scheme under an achromatic condition provides extremely high extraction efficiency. We have encountered a beam instability in the debunch formation process, which is estimated to be triggered by a longitudinal microstructure of the beam. To suppress this instability, the beam to the MR has been injected into the RF bucket with a phase offset. A newly developed RF manipulation, 2-step voltage debunch, has successfully pushed up the beam power up to 64.6 kW keeping a high extraction efficiency of 99.5%. A drastic beam loss reduction has been demonstrated in the beam test using a diffuser installed upstream of the first electrostatic septum (ESS1). 8 GeV bunched slow extraction tests for the neutrino-less muon to electron conversion search experiment (COMET Phase-I) have been successfully conducted.
|
|
DOI • |
reference for this paper
※ doi:10.18429/JACoW-HB2021-THDC1
|
|
About • |
Received ※ 18 October 2021 — Revised ※ 22 October 2021 — Accepted ※ 22 November 2021 — Issued ※ 03 December 2021 |
Cite • |
reference for this paper using
※ BibTeX,
※ LaTeX,
※ Text/Word,
※ RIS,
※ EndNote (xml)
|
|
|