Stimulated brillouin scattering in a plasma with ion-acoustic turbulence

A theory of stimulated Brillouin scattering (STBS) in a plasma with ion-aco ustic turbulence is developed using concepts of parametric instability unde r conditions when equations of two-temperature hydrodynamics can be used to describe ion-acoustic perturbations of the electron density. The temporal growth rate of the absolute instability and the spatial gain of the scatter ed wave are determined. The dependence of the threshold density of the radi ation flux on the angle between the scattering wave vector and the directio n of anisotropy of the turbulent noise is described. A new effect of STBS f orbiddenness caused by anomalous turbulent heating of the ions is predicted for a plasma with a high level of turbulent noise. (C) 2000 MAIK "Nauka/In terperiodica".