Zur elektromagnetischen Strahlung magnetfeldfreier Elektronenplasmawellen bei isotropem und anisotropem Gasdruck

Abstract

In previous studies the electromagnetic radiation resulting from nonlinear self-interaction of electron plasma waves was treated by taking the electron pressure to be isotropic. Here we determine the radiation flux in the far field of the disturbance for the anisotropic case, too. By assuming statistical homogeneity in space and time and accounting only for pair correlations of the particle density the mean flux near the second harmonic of the plasma frequency can be expressed by the energy spectrum of the primary waves. As an application we find approximate formulae for coronal conditions (type II and III bursts). The anisotropy corrections are of the order (a/c)2 (a=electron sound velocity, c = velocity of light).