Electrostatic Drift Ion Cyclotron Waves in Sheet Plasmas with and without Ambipolar Field

Abstract

Electrostatic drift ion cyclotron waves in the presence as well as in the absence of an ambipolar field in a sheet plasma of thickness of the order of the ion Larmor radius have been studied numerically. The frequency range considered is of the order of ion cyclotron frequency ω_ci. The method is based on an integral equation in the wavenumber space derived from the Vlasov-Poisson system of equations. Eigenfrequencies and eigenfunctions of the waves with and without ambipolar field are studied by varying the plasma thickness, the perpendicular wavenumber and the parallel wavenumber. A strong ambipolar field seems to be effective for the suppression of the drift ion cyclotron instability in sheet plasmas. The validity of local dispersion relation is checked.