Characteristic studies on hollow electron beam in HIRFLCSR ecooler system

Cooling force in electron cooling system is closely related to the temperature of electron beam. The velocity of electron has the offset due to space charge of intense electron beam. In order to minimize this effect, a new type of electron gun to produce the hollow electron beam is firstly adopted in HIRFLCSR ecooler project. The hot ion beam is cooled by Coulomb interaction with intense and cold hollow electron beams. By analysis of space charge effect of solid and hollow electron beam respectively, the impact on the electron velocity and additional temperature due to the space charge field are preliminarily investigated.