IPAC2022 - List of Authors (Shobuda, Y.)

Paper	Title	Page
WEOYGD1	Recent Results of Beam Loss Mitigation and Extremely Low Beam Loss Operation of J-PARC RCS	1616
	P.K. Saha, H. Harada, T. Nakanoya, K. Okabe, H. Okita, Y. Shobuda, F. Tamura, M. Yoshimoto JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan H. Hotchi KEK, Tokai, Ibaraki, Japan
	In the 3-GeV RCS (Rapid Cycling Synchrotron) of J-PARC (Japan Proton Accelerator Research Complex), multi-turn charge-exchange injection of H⁻ by using a thin stripper foil is performed to achieve high-intensity proton beam of 1 MW. The beam loss at 1 MW has already been well controlled, but for further minimizing both uncontrolled and controlled beam losses caused by the foil scattering of the circulating beam, recently we have implemented a lower vertical injection beam size and installed a corresponding smaller size stripper foil. A smaller foil gives a significant reduction of the foil scattering uncontrolled beam loss at the injection area, while an optimization of the vertical transverse painting area matching with a smaller beam size further gives an extremely reduction of the beam loss at the collimator section. The corresponding residual radiation at the recent operation with 700 kW beam power was also measured to extremely reduced.
	Slides WEOYGD1 [1.161 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEOYGD1
About •	Received ※ 20 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 24 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOZSP3	Measurements of Radiation Fields From a Ceramic Break	1663
	Y. Shobuda, S. Hatakeyama, M. Yoshimoto JAEA/J-PARC, Tokai-mura, Japan T. Toyama KEK, Tokai, Ibaraki, Japan
	Ceramic breaks are used in synchrotrons for many purposes. For example, they are inserted between the Multi-Wire Profile Monitor (MWPM) on the injection line at the Rapid Cycling Synchrotron (RCS) in J-PARC to completely prevent the wall currents accompanying beams from affecting the MWPM. On the other hand, from the viewpoint of suppressing beam impedances and the radiation fields from the ceramic breaks, it would be preferable that the inner surface of the ceramic break is coated with Titanium Nitride (TiN), or covered over capacitors. In this report, we measure the radiation fields from the ceramic break with and without capacitors as well as the beam profile and investigate the effect of the ceramic breaks on the measurements.
	Slides WEOZSP3 [35.441 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEOZSP3
About •	Received ※ 12 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 24 June 2022 — Issue date ※ 05 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Recent Results of Beam Loss Mitigation and Extremely Low Beam Loss Operation of J-PARC RCS

1616

P.K. Saha, H. Harada, T. Nakanoya, K. Okabe, H. Okita, Y. Shobuda, F. Tamura, M. Yoshimoto
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
H. Hotchi
KEK, Tokai, Ibaraki, Japan

In the 3-GeV RCS (Rapid Cycling Synchrotron) of J-PARC (Japan Proton Accelerator Research Complex), multi-turn charge-exchange injection of H⁻ by using a thin stripper foil is performed to achieve high-intensity proton beam of 1 MW. The beam loss at 1 MW has already been well controlled, but for further minimizing both uncontrolled and controlled beam losses caused by the foil scattering of the circulating beam, recently we have implemented a lower vertical injection beam size and installed a corresponding smaller size stripper foil. A smaller foil gives a significant reduction of the foil scattering uncontrolled beam loss at the injection area, while an optimization of the vertical transverse painting area matching with a smaller beam size further gives an extremely reduction of the beam loss at the collimator section. The corresponding residual radiation at the recent operation with 700 kW beam power was also measured to extremely reduced.

Slides WEOYGD1 [1.161 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEOYGD1

About •

Received ※ 20 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 24 June 2022

Cite •

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

WEOZSP3

Measurements of Radiation Fields From a Ceramic Break

1663

Y. Shobuda, S. Hatakeyama, M. Yoshimoto
JAEA/J-PARC, Tokai-mura, Japan
T. Toyama
KEK, Tokai, Ibaraki, Japan

Ceramic breaks are used in synchrotrons for many purposes. For example, they are inserted between the Multi-Wire Profile Monitor (MWPM) on the injection line at the Rapid Cycling Synchrotron (RCS) in J-PARC to completely prevent the wall currents accompanying beams from affecting the MWPM. On the other hand, from the viewpoint of suppressing beam impedances and the radiation fields from the ceramic breaks, it would be preferable that the inner surface of the ceramic break is coated with Titanium Nitride (TiN), or covered over capacitors. In this report, we measure the radiation fields from the ceramic break with and without capacitors as well as the beam profile and investigate the effect of the ceramic breaks on the measurements.

Slides WEOZSP3 [35.441 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEOZSP3

About •

Received ※ 12 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 24 June 2022 — Issue date ※ 05 July 2022

Cite •

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