Improvements of vacuum system in J-PARC 3 GeV synchrotron

8th International Particle Accelerator Conference

Kamiya, J.^1 ; Hikichi, Y.^1 ; Namekawa, Y.^1 ; Takeishi, K.^1 ; Yanagibashi, T.^1 ; Kinsho, M.^1 ; Yamamoto, K.^1 ; Sato, A.^2

J-PARC, Japan Atomic Energy Agency, Shirakata 2-4, Tokai, Naka, Ibaraki, Japan^1

Nippon Advanced Technology Co. Ltd., Muramatsu 3129-45, Tokai, Naka, Ibaraki, Japan^2

关键词: Beam injection;    Controller failure;    Electrical noise;    Kicker magnets;    Long cables;    RF cavities;    Spring constants;    Vacuum system;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/874/1/012099/pdf
DOI  :  10.1088/1742-6596/874/1/012099

来源: IOP

【 摘 要 】

The RCS vacuum system has been upgraded since the completion of its construction towards the objectives of both better vacuum quality and higher reliability of the components. For the better vacuum quality, (1) pressure of the injection beam line was improved to prevent the H-beam from converting to H0; (2) leakage in the beam injection area due to the thermal expansion was eliminated by applying the adequate torque amount for the clamps; (3) new in-situ degassing method of the kicker magnet was developed. For the reliability increase of the components, (1) A considerable number of fluoroelastmer seal was exchanged to metal seal with the low spring constant bellows and the light clamps; (2) TMP controller for the long cable was developed to prevent the controller failure by the severe electrical noise; (3) A number of TMP were installed instead of ion pumps in the RF cavity section as an insurance for the case of pump trouble.