HF conductivity of parametrically unstable magnetized plasma

Abstract

Summary form only given. The anomalous absorption of high-frequency (HF) pump wave in a nonequilibrium magnetized plasma was studied early on the basis of the kinetic theory of fluctuations. The frequency bands in which the effective HF power dissipation mechanisms exist in a thermonuclear and space plasmas are the lower hybrid (LH) and upper hybrid (UH) regions. In this report the HF power absorbed in the plasma is determined under the conditions characteristic of the parametric decay of the LH and UH wave into the secondary wave and low-frequency plasma oscillations ( ion-sound modes, convective cells, electron drift waves). It is shown that the anomalous absorption can be caused by scattering of charged particles from turbulent fluctuations of an electric field that is described by HF plasma conductivity. We have calculated HF conductivity and the effective absorption lengths of pump energy. It is shown that for the thermonuclear plasma the effective absorption length is of the same scale as plasma dimension that ensures effective dissipation of the HF pump power.