Studies on electron cloud instability in BEPC II

Electron Cloud Instability has been studied in the operation of BEPC. The BEPC II began the commissioning in November 2006 and the positron beam current has reached 500 mA. Because of such a high beam current, some instabilities such as ECI, bunch lengthening et al, have appeared during the operation. The experimental investigation on ECI during the commissioning of BEPC II will be reported in this paper.