Kinetic instability of plasma with the anisotropic ion distribution function

Homogeneous plasma in a constant magnetic field was studied. The plasma gas-kinetic pressure was assumed to be of the same order as the pressure of the magnetic field, and the electron distribution function was anisotropic. The aim of the study was to examine the stability of such plasma in the range of frequencies above the ion cyclotron frequency but below the electron cyclotron frequency. Since purely electronic oscillations were studied, it was sufficient to consider only the electron motion. Electrons are described by means of the kinetic equation. It is shown that if the gas-kinetic pressure of the plasma along the constant magnetic field exceeds that across the magnetic field, the instability due to buildup by resonance electrons is excited on the oscillation branch under examination. Increments are calculated. When the plasma pressure along the magnetic field exceeds that across the latter, aperiodic buildup of this branch by nonresonance electrons is possible. The resonance buildup occurs precisely in that range of wave vectors where aperiodic buildup is absent