Simulation and analysis of secondary emission microwave electron gun

The development of high-current, short-duration pulses of electrons has been a challenging problem for many years. Micro-pulse-gun (MPG) is a novel concept that employs the resonant amplification of an electron current by secondary electron emission in a RF cavity. Using the computation code URMEL-T, several kinds of RF cavity under the frequency of 2856MHz were calculated and optimized, the magnetic and electric field distribution in them were got. Through particle-in-cell (PIC) simulation, the self-bunching process in a MPG was proved, the relation between the cavity length and selected phase and the relation between the peak electric field and selected phase were got. With cathode material of high secondary emission coefficient, the MPG can produce high current densities (1132~5303A/cm2