Transport Barriers Formation and Subneoclassical Energy Fluxes: A Unified Theoretical Approach

Abstract

We show that ``subneoclassical'' heat fluxes are rigorous and straightforward consequences of the revisited neoclassical theory---including finite Larmor radius (FLR) and inertia effects---that we published earlier [Phys. Plasmas 1, 619 (1994)]. The formation of sheared radial electric field profiles displaying most of the characteristics observed in the transport barriers associated with $L\ensuremath{-}\mathrm{to}\ensuremath{-}H$ transitions is another consequence of this first principles theory. The threshold condition results from a competition between rotation spin-up related to FLR and friction by charge-exchange neutrals.