Anomalous transport coefficients in a turbulent plasma

Abstract

A general self-consistent framework is developed for the calculation of transport coefficients in a collisionless, weakly turbulent plasma. These coefficients characterize the response to a perturbation away from a quasi-steady turbulent state, which is assumed to exist as a result of the stabilization of the linear instabilities. It is shown that a purely hydrodynamical description does not exist for plasmas: the macroscopic picture must include non-conserved quantities, which lead to the plasmadynamical (or ‘two-fluid’) picture of the system. The number of independent transport coefficients, necessary for the macroscopic characterization of the plasma, is correspondingly increased as compared with a two- component mixture of two ordinary fluids. The typical turbulent contributions to the transport coefficients are clearly exhibited.