Plasmadynamics near a self-similar turbulent state

Abstract

The transport properties of a turbulent plasma are investigated in the vicinity of a self-similar turbulent state (SSTS). This state plays the same role of reference as the local equilibrium for a collisional plasma. The stability of the SSTS against velocity gradients is proved. Under certain well-defined conditions a plasma- dynamical regime is established, in which the initial conditions are forgotten and the macroscopic plasmadynamical quantities obey closed differential equations. The anomalous viscosity arising in this regime is investigated in detail. This quantity is time-dependent (a feature impressed by the self-similar character of the reference state). A number of additional typically turbulent terms appear in the equation of motion: they arise from interference between flow and collisions or magnetic field.