The Dissipation Process of Beam Energy in the Plasma Produced by Pulse Electron Beam

摘要

The dissipation process of beam energy was investigated experimentally in the plasma produced by the pulse electron beam. The digital data acquisition system constructed by fast A/D converter and personal computer was developed to examine into the temporal evolutions of both plasma and beam electron distribution functions. It was observed that the bump-on-tail distribution function in the early times after the beam injection and the production of high energy electron beams with the increasing energy. The mechanism for the production of high energy electrons can be qualitatively explained by the Landau damping of two-stream instability caused by the wave-particle interaction, suggested by the q uasilinear theory. The injected beam energy was dissipated through the collision between the above mentioned high energy electrons and neutral particles.