Electrostatic ion cyclotron instability in a plasma with q-nonextensive distributions

Abstract

The general dispersion relation for electrostatic waves in magnetized plasmas is derived using the standard linear Vlasov theory and the q-distribution of Tsallis statistics. The dispersion relation is solved for a plasma that has nonextensive electrons drifting with respect to stationary ions, and satisfies the other conditions for the excitation of electrostatic ion cyclotron waves. The frequency spectrum and growth rate are obtained for the electrostatic ion cyclotron waves. The marginally stable state is investigated for the onset of instability. It is shown that decreasing the non-extensivity parameter of electrons strengthens the instability and decreases the minimum value of the critical drift velocity, whereas larger temperature anisotropy of ions weakens the instability and increases the minimum value of the critical drift velocity.