Influence of electromagnetic radiation on the shock structure formation in complex plasmas

Abstract

Electromagnetic radiation effects are calculated for the case of the solar radiation spectrum in the vicinity of the Earth. The influence of the photoelectric effect on the propagation of nonlinear waves in complex plasmas is studied when the dust grains acquire large positive charges. Exact solutions to nonlinear equations in the form of steady-state shocks that do not involve electron-ion collisions are found, and the conditions for their existence are obtained. In contrast to the classical collisionless shock waves, the dissipation due to the dust charging involves the interaction of the electrons and ions with the dust grains in the form of microscopic grain currents and the photoelectric current. The nonsteady problem of the evolution of a perturbation and its transformation into a nonlinear wave structure is considered. The evolution of an intense, initially nonmoving region with a constant increased ion density is investigated. It is shown that the evolution of a rather intense nonmoving region with a constant increased ion density can result in the formation of a shock wave. In addition to the compressional wave, a rarefaction region (dilatation wave) appears. The presence of a dilatation wave finally leads to the destruction of the shock structure. The possibility is discussed of the observation of shock waves related to dust charging in the presence of electromagnetic radiation in active rocket experiments, which involve the release of a gaseous substance in the Earth's ionosphere in the form of a high-speed plasma jet at altitudes of 500–600 km.