The Effect of Ambipolar Field for the Electrostatic Ion Cyclotron Waves in Sheet Plasmas

Abstract

The effects of ambipolar static electric field on the electrostatic ion cyclotron waves in a sheet plasma of thickness of the order of the ion Larmor radius ρ_i have been studied numerically. The method is based on an integral equation in the wavenumber space derived from the Vlasov-Poisson system of equations and on the direct computation of the integral equation. The effect of ambipolar field for eigenfrequencies and eigenfunctions is studied systematically by varying the plasma thickness and the electron-to-ion temperature ratio. A strong negative ambipolar field seems to be effective for the penetration of r.f. field in sheet plasmas. The basic features for the case of the ideal sheet plasma, where the plasma thickness is equal to ρ_i, are explained by a physical model.