Secondary electron emission from the surface of the kicker magnets of RCS in J-PARC

Kamiya, Junichiro   ; Yamamoto, Kazami   ; Ogiwara, Norio; Kinsho, Michikazu  

The rapid-cycling synchrotron (RCS) in J-PARC has succeeded to accelerate proton beam up to 3 GeV. The buildup of the beam power is performed over the next several years. The quality of the vacuum of the RCS is the key element for the beam power augmentation. The extraction kicker magnets have been installed in the vacuum chambers to prevent the electrical discharge. Therefore, the vacuum characteristic of the kicker magnet will become very important for the buildup of the beam. We have focused our effort to reduce the outgassing from the kickers. In addition, we have to care for the phenomenon which is caused by the interaction between the beam and the residual gass or vacuum surface. Especially, the secondary electron emission (SEE) coefficient is very important factor because SEE is the source of the electron cloud which caused the beam instability. In this report, the SSE coefficients of the components of the kicker magnet are systematically shown.