Collisionless solar wind. II - Variable electron temperature.

Abstract

Examination of a two-component ?model' for the solar wind, in which the protons become collisionless beyond a distance from the solar center equal to or greater than 10 solar radii, where they are already highly supersonic. The proton temperatures are found from the double adiabatic equation of state. The electrons are highly subsonic, and their temperature profile is prescribed ad hoc. The momentum equations for the electrons and protons are solved subject to the conditions of quasi-neutrality and zero charge efflux from the sun. Some of the principal results are: (1) the proton thermal anisotropy is substantially reduced when solar rotation is considered; (2) solar rotation leads to significantly lower mean proton temperatures; and (3) the electron temperature profile in the supersonic region is the primary parameter determining flow acceleration there.