Theoretical modeling of drift cyclotron loss-cone instability mode structures

Abstract

Measurements of the drift cyclotron loss-cone instability mode structure have recently been performed on MIX [Phys. Fluids 29, 3439 (1986)], an axisymmetric mirror machine characterized by a small width Maxwellian cold stream and a larger width loss-cone plasma. To model these measurements the Fourier-space integral equation was solved, derived from the linearized Vlasov equation for electrostatic perturbations, with both a matrix version technique and a WKB approximation. It is found that the mode is prohibited from the cold stream region by the process of mode conversion, which explains experimental results quite well.