Model for formation of field-reversed configurations in theta pinches

Summary form only given. A model is being developed for considering various effects which might limit FRC (field-reversed configuration) formation. The model contains two components, the zero-order (unperturbed) and the first-order (perturbed) parts. The zero-order solution represents the more-or-less ideal evolution of the FRC during the formation phase, i.e. its plasma is assumed, a priori, to be axially and azimuthally symmetric. The first-order solution describes the perturbed behavior (including both azimuthal and axial asymmetries). The zero-order model includes a two-part plasma composed of a core and a current sheath. Each part is given a specified rigid-rotor-like radial profile and a square-ends axial profile. Adopting a fixed profile family reduces the model to a zero-dimensional, time-dependent problem that can be readily computed on a personal computer. The zero-order model will be used to understand the influence of impurity radiation loss on the achievable temperatures and also the possible failure to burn through at increased impurity levels