Dispersion Characteristics of Low-Frequency Electron Waves in a Magnetoactive Plasma of Arbitrary Density

Abstract

The article studies waves in a collisionless magnetoactive plasma with frequencies much lower than the electron cyclotron frequency at an arbitrary ratio between the electron plasma and cyclotron frequencies. A general dispersion relation is obtained for the wave frequency as a function of the wave vector and the ratio of the plasma frequency to the cyclotron frequency. This relation is a bicubic equation with respect to frequency. Based on this equation, the existence domains of various wave modes depending on the specified parameter, their group velocity, polarization, and energy density are studied. Special attention is paid to low-frequency whistler waves in a low-density plasma, since, among the propagating wave modes existing in the specified range of parameters, whistler waves have the highest refractive index and play an important role in theresonant interaction of waves and particles.