Energy Flow in the Collision of Two Plasma Streams

Abstract

The axial distribution of transverse energy density during the collision of two plasma streams was measured by means of four magnetic loops arranged axially in the region of a guide field.
The transverse energy density has the maximum, 4×10¹⁵ eV/cm³, in the midplane which is about five times larger than that of a one-sided plasma stream. The transverse energy density in the midplane decreases typically by a factor of 4 in 20-μ sec, and the axial distribution is flattened out.
It is not possible to account for this rapid decay of plasma diamagnetism quantitatively by the adiabatic expansion model developed by F. Waelbroeck et al.
A simple model of axial thermal conduction is developed in which the energy is transported to cold plasma regions through shock fronts.
Predictions of the model concerning the variation of plasma diamagnetism indicate that energy flow due to parallel thermal conduction cannot be excluded.