Study Of High Current Short Pulse Electron Gun

With the continuous development of electron accelerator physics and technology,the electron gun has been widely concerned as it is always been one of the vitalcomponents in electron accelerator which generates the electron beam. High beamcurrent with short pulse length will become an important research direction about theelectron gun. At present, the high current short pulse electron gun has a rapiddevelopment all around the world. In this paper, it will be introduced some researchwork about two kinds of electron gun with high current and short pulse at IMP.At first, this paper introduces the research work about the vacuum arc pulseelectron gun installed in dielectric wall accelerator at IMP. It mainly contains4parts：the study of formation and physical processes about vacuum arc discharge; coming upwith the design parameters of the electron gun; making use of the vacuum arcdischarge characteristics, we designed the electron cathode--flashboard and did someexperiments to verify the reliability of generating pulsed electron beam; making thecomputer simulation of the electrostatic field distribution inside the vacuum arc pulseelectron gun. After testing, the electron gun generated the pulse electron beam and thepeak beam intensity exceeded2.5amps. The pulse length could be adjusted fromnanosecond to microsecond. The coefficient exceeded7.2×10–6P, achieved the basicrequirements of the experimental test platform about the dielectric wall accelerator.Secondly, in order to meet the experimental requirements which based on makeuse of the electron beam to diagnose the high energy density physics, this paper makean introduction about the primary design of a C-band photocathode RF electron gun.The pulsed electron gun can generate electron beam by photoelectric effect, simultaneously the electron beam is accelerated to the speed of light at a short time bythe high microwave field in1.6-cell RF cavity, for obtaining a small emittance. Thischapter mainly can be divided into two parts: first part is selecting the photocathodematerial, referring to the related experimental results about the other laboratories,combined with the experimental requirements, we are going to use copper as thephotocathode material and determine the cathode shape and size. Furthermore, inorder to control the emittance, microwave parameters of the RF cavity are simulatedby computer: simulating the influence on axial microwave field by the lengthrelationship between the two cavities; the linear relationship between the cavity radiusand radial microwave field; the relationship between RF cavity radius and the workingfrequency, these computer simulation results will make a reliable foundation for thefuture research of the C-band photocathode RF electron gun...