Small scale irregularities in Comet Halley's plasma mantle: An attempt at self-consistent analysis of plasma and magnetic field data

VEGA-1 measurements of the plasma density and magnetic field in the coma of Comet Halley show characteristic signatures over a significant portion of the outbound pass. It is found that the assumption that there is a balance between the thermal and magnetic pressures in these features can be used to obtain estimates of the plasma temperature as a function of distance from the nucleus. These estimates indicate that the ions cool from ∼1.5 x 106 degree K at 105 km to 2 x 105 degree K at 5 x 104 km. The technique used here represents a novel approach whereby temperature measurements can be made in situations where only plasma density and magnetic field data are available