The influence of striction density perturbations on the excitation of plasma oscillations inside thermal inhomogeneities of plasma

Abstract

In this paper, we continue our studies begun in [Izv. Vyssh. Uchebn. Zaved., Radiofiz.,41, No. 3, 270 (1998)].Calculating the coefficients and nonlinear phase shift in the equation for plasma-wave intensity introduced in the eralier paper, we have solved the problem of the influence of striction perturbations of the plasma density on the excitation of shortwave plasma oscillations by an electromagnetic wave; the above oscillations are captured in a volume of inhomogeneities, which are extended along the magnetic field and have reduced electron density that crosses the level of the upper-hybrid resonance. The dissipative processes of absorption and emission of plasma waves beyond the inhomogeneity are assumed to be weak. The variation of excitation and reflection of plasma waves from the resonance level due to deformation of the plasma- density profile is described. The band of effective generation of eigenmodes of captured oscillations as a function of the total wave-phase increment in an inhomogeneity is determined. The effect of penetration of the field of a high-power plasma wave into the non-transmittance region as a result of the striction expulsion of plasma is calculated. With allowance for the nonlinear phenomena in question, we estimated the heating of artificial inhomogeneities of thermal origin as a result of collisional absorption of the plasma oscillations excited in a volume of inhomogeneities under the action of a high-power radio wave.