Relativistic electron beam-plasma instability and interaction with electromagnetic wave.

摘要

A plasma particle simulation was undertaken to study the growth rate of the relativistic beam-plasma electromagnetic instability. The linear dispersion relation for the relativistic beam-plasma electromagnetic instability is derived and solved numerically for the growth rate of the electromagnetic field. The linear growth rate is solved as a function of beam velocity and wavenumber. The results are compared with plasma particle simulations conducted using MAGIC, a particle in cell code developed by Mission Research Corporation under the auspices of the Air Force Office of Scientific Research. The resulting particle simulation growth rates, as a function of beam velocity and wavenumber, agree with linear theory. The saturation of the beam-plasma instability agrees with quasi-linear theory. Electromagnetic turbulence develops from the relativistic beam-plasma instability. The interaction of the electromagnetic turbulence with an incident electromagnetic wave, at {dollar}omega = omegasb{lcub}p{rcub}{dollar} where {dollar}omegasb{lcub}p{rcub}{dollar} is the plasma frequency, is studied by the use of Fourier spectrum. A scattered wave spectrum is observed at {dollar}omega = 2omegasb{lcub}p{rcub}.{dollar}