IPAC2011 - List of Authors (Kameda, J.)

Paper	Title	Page
MOPC016	Development of a New RF Accelerating Cavity for J-PARC Ring Accelerator	98
	Y. Morita, T. Kageyama KEK, Ibaraki, Japan J. Kameda ICRR, Chiba, Japan S. Yamashita ICEPP, Tokyo, Japan
	Funding: Japan Society for the Promotion of Science (JSPS) To enhance the beam power delivered by the J-PARC* ring accelerators, upgrading the accelerating cavities is indispensable. In particular, long term stable operation of the present cavities for the RCS is one of the important issues. Currently, the cavities are loaded with FINEMET* cores cooled by water, where every core is coated with glass cloth and epoxy resin for waterproof. However, it was reported that some of the cores were damaged by thermal stress. We are developing a new cavity loaded with multi ring core modules. Each core module consists of three ring cores concentrically arranged and sandwiched between two glass epoxy plates with flow channels grooved. The ring cores without waterproof coating are cooled by the turbulent flow of a chemically inert liquid (Fluorinert), since FINEMET is subject to corrosion in water. We have designed and built a high power prototype cavity loaded with a single core module, then carried out low level measurement and high power test. Finally, the cavity has been stably operated up to an average power loss of 10 kW per core module, which is 1.7 times higher than that for the present RCS cavity. Japan Proton Accelerator Research Complex Rapid-Cycling Synchrotron **FINEMET is an iron-based magnetic alloy produced by Hitachi Metals, Ltd..

Paper

Title

Page

Development of a New RF Accelerating Cavity for J-PARC Ring Accelerator

98

Y. Morita, T. Kageyama
KEK, Ibaraki, Japan
J. Kameda
ICRR, Chiba, Japan
S. Yamashita
ICEPP, Tokyo, Japan

Funding: Japan Society for the Promotion of Science (JSPS)
To enhance the beam power delivered by the J-PARC* ring accelerators, upgrading the accelerating cavities is indispensable. In particular, long term stable operation of the present cavities for the RCS** is one of the important issues. Currently, the cavities are loaded with FINEMET*** cores cooled by water, where every core is coated with glass cloth and epoxy resin for waterproof. However, it was reported that some of the cores were damaged by thermal stress. We are developing a new cavity loaded with multi ring core modules. Each core module consists of three ring cores concentrically arranged and sandwiched between two glass epoxy plates with flow channels grooved. The ring cores without waterproof coating are cooled by the turbulent flow of a chemically inert liquid (Fluorinert), since FINEMET is subject to corrosion in water. We have designed and built a high power prototype cavity loaded with a single core module, then carried out low level measurement and high power test. Finally, the cavity has been stably operated up to an average power loss of 10 kW per core module, which is 1.7 times higher than that for the present RCS cavity.
*Japan Proton Accelerator Research Complex
**Rapid-Cycling Synchrotron
***FINEMET is an iron-based magnetic alloy produced by Hitachi Metals, Ltd..