baking method for degassing of a kicker magnet in accelerator beam line

Kamiya, Junichiro   ; Ogiwara, Norio; Yanagibashi, Toru*; Kinsho, Michikazu  ; Yasuda, Yuichi*

In this study, we propose a new degassing method by which only kicker magnets in the accelerator beam line are baked out without raising the temperature of the vacuum chamber to prevent unwanted heat expansion of the chamber. The bake-out system comprises the heater and thermal radiation shield plates, which are installed between the kicker magnet and the chamber wall. The result of the verification test showed that each part of the kicker magnet was heated to above the target temperature with a small rise in the vacuum chamber temperature. A graphite heater was selected in this application to bake-out the kicker magnet in the beam line to ensure reliability and easy maintainability of the heater. The vacuum characteristics of graphite were suitable for heater operation in the beam line. A preliminary heat-up test conducted in the accelerator beam line also showed that each part of the kicker magnet was successfully heated and that heat expansion of the chamber was negligibly small.