Electron-cloud and e–p Instability in J-PARC

Abstract

Electron cloud effect has been studied for J–PARC RCS (Rapid Cycling Synchrotron) and MR (Main Ring). Numerical simulation shows electron cloud may build-up to the neutralization level of a few %. With a linear theory and numerical simulation, electron-proton (e–p) instability is examined. Electron cloud observation at the KEK–PS is also discussed for comparison. The present investigation shows that e–p instability in the J–PARC rings will be manageable, assuming some remedies such as local solenoid magnets.