On the alfven waves energy transformation and plasma heating by acoustic waves during stimulated Mandelstam-Brillouin scattering in a plasma layer

It is reported on interaction of Alfven and sound waves in a plasma layer. An analysis has been carried out for two limiting cases of a nonlinear sound wave generation by Alfven waves with a fixed phase and of excitation of sound oscillations with a chaotic phase by Alfven waves possessing also a random phase. Equations have been derived for interacting waves with taking account of sound field harmonics. The equations have been solved in an approximation of the preset field of Alfven waves. The distribution of fields inside the layer has been calculated on a computer and the results reported. Kinetic equations for wave intensities have been derived and solved in the approximation of chaotic phases. The efficiency of plasma heating has been estimated. The problem of sound generation by Alfven waves in a plasma layer is of interest for plasma diagnostics and also for interpretation of a number of effects in a cosmic plasma, for instance, excitation of quasiperiodic H4 pulsations in the Sun atmosphere