Theory of anomalous transport in high-aspect-ratio toroidal helical plasmas

Abstract

A theoretical model of the anomalous transport in torsatron-heliotron plasmas is developed, based on the current-diffusive interchange instability which is destabilized due to the averaged magnetic hill near the edge. An analytic formula of the transport coefficient is derived. This model explains the large edge transport, the power degradation and energy confinement scaling law, and the enhanced heat-pulse thermal conduction.