Moving perturbations of the ionization in a field of strong electromagnetic waves

Abstract

The perturbation of the ionization and of the electron temperature is considered in a plasma in a field of strong electromagnetic waves. It is shown that the intensified absorption of the waves in the region of their reflection leads to the appearance of the moving perturbations of the plasma ionization. The conditions governing the development of moving perturbations are determined along with their velocity and spatial structure. It is demonstrated that in a weakly inhomogeneous plasma such perturbations appear in the neighborhood of the reflection point of the waves and move toward the wave so as to cause perturbation. This leads to the generation of nondecaying nonlinear oscillations in the plasma. The frequency of the oscillations is determined, and it decreases with increasing absorbed power of the waves.