About the equilibrium and stability of the magnetopause

Abstract

This paper offers a model of the magnetopause based on the theory of the contact discontinuity; the boundary layer between the two states of space plasma. The structure of the magnetopause is explored for the effects of polarization, and the profiles of the polarizing electrostatic field are obtained.The structural stability of the model of a non-electroneutral magnetopause is studied. The areas of existence of the solutions of the contact discontinuity are revealed. These solutions are realized only within some areas of the 4-dimensional parametric space of the problem. The phase volume of these regions is small in comparison with all phase volumes of the domain of definition of the model parameters.Methods for studying the stability of the magnetopause by taking into account the effects of plasma polarization are proposed. The kinetic equation with a self-consistent electromagnetic field is solved for the perturbation of the distribution function. Based on this solution, the plasma permittivity tensor of the non-electroneutral contact discontinuity is computed, and the dispersion equation for the examination of possible modes of instability of this discontinuity obtained. The instability of the magnetopause is explored with respect to the tearing perturbation and the effects of plasma polarization on the development of tearing instability.