New nonlocal analysis of collisionless drift wave in Vlasov plasma

Abstract
The WKB-type eigenmode analysis of an inhomogeneous Vlasov plasma is developed based on the exact integral equation. Thermal effects, namely, effects associated with the finite Larmor radius, Landau damping, cyclotron damping and so on are taken into account even if k2ρ2≳≳1 [k is of the order of ‖ψ′ (x)/ψ‖ ]. The ’’quantization condition,’’ which determines the eigenfrequency, is derived from the global localization condition of solutions. In the case of weak dissipation, this quantization condition reduces to a simple and more tractable form. Drift waves in a straight magnetic field with Gaussian density distributions are discussed numerically and analytically in detail. Results show that the growth rate of the fundamental mode (n=0) is the largest one.