Radial transport, end loss, and ambipolarity in tandem mirrors

A simple one-dimensional (radial) model describing end loss and radial transport in a tandem mirror is developed. The model enables a self-consistent calculation of various ambipolar potential profiles and the center-cell density profile in the presence of either conducting or insulating end walls. Results of the computation reproduce many features seen in the Tandem Mirror Experiment (TMX). Signatures of radial transport are delineated, and the effect on confinement is studied over a range of parameters. Optimal and critical values in parameter space are also investigated