Computation of E-Layer and Plasma Equilibria in Astron

Abstract

The equilibrium magnetic field for astron configurations is computed; a given vacuum magnetic field and the fields due to the E layer and plasma are included, assuming axial symmetry and Bθ≡0. The components Br(r, z) and Bz(r, z) are derived from the stream function ψ(r, z) = rAθ. The E-layer is described by a distribution function that depends on the canonical angular momentum and the energy. Various models of the E layer have been used and are discussed. The function ψ(r, z) satisfies a nonlinear partial differential equation (Ampere's law) that is solved by finite-difference methods, using an iterative procedure. The object is to find equilibrium solutions with a reversed field in the central region that can contain a plasma. Examples of reversed field equilibria corresponding to various E layer distributions are presented. Simple models for the plasma are assumed, and equilibria of the coupled system of E layer plus plasma are computed.