Anomalous Resistivity and Parallel Electric Fields

Abstract

Plasma phenomena involving anomalous resistivity and large, quasi-static electric fields parallel to magnetic field lines are of extreme importance to fundamental plasma physics, to fusion studies, and to the dynamics of astrophysical plasmas. The fundamental plasma physics interest stems from the incomplete experimental and theoretical understanding of the variety of instability and saturation mechanisms possible under different conditions. The fusion interest is associated with plasma heating as well as with anomalous diffusion that may limit confinement times. The astrophysical interest, typified by magnetospheric physics, is connected with particle acceleration by parallel potential differences, decoupling of the magnetosphere-ionosphere dynamics by large parallel electric fields and the relationship of anomalous resistivity to substorms, current continuity paths, and other phenomena. Anomalous resistivity may also accompany particle acceleration on the Sun, Jupiter, radio and X-ray emitting bodies, pulsars, etc. Such processes are difficult to study in the laboratory due to the inherent difficulties of the experiments as well as the problems of knowing and scaling physical parameters appropriately. Thus, magnetospheric research on anomalous resistivity may be vital to plasma and astrophysics as well as to magnetospheric physics, and it may have practical applications in fusion studies.