Particle Simulations for Electron Beam-Plasma Interactions

摘要

The computer simulations of high-frequency instabilities excited by the high density electron beam and their nonlinear effect are presented.One-dimensional electromagnetic particle simulations are performed with different values of the electron beam-to-plasma density ratio.The results show that for the high electron beam-to-background plasma density ratio,all the Langmuir waves and two electromagnetic waves with left-hand and right-hand circular polarizations(i.e.,the“L-O mode”and the“R-X mode”)propagating parallel to the magnetic field can be generated and the maximum values of wave electric fields are nearly the same.The electron beam and background plasma are diffused and a part of energetic background electrons are obviously accelerated by the wave-particle interactions.The heating of the beam and background plasma is mainly due to the electrostatic(Langmuir)wave-particle interactions,but the accelerations of a part of energetic background electrons may be mainly due to the electromagnetic wave-particle interactions.