Diffusion cooling in a magnetic field

Diffusion cooling of electrons in a weakly ionized plasma in the presence of a magnetic field is studied using the balance equations of momentum transfer theory, well known in “swarm” or test particle analysis. It is shown that for a cylindrical, axially symmetric system, the electron temperature profile can be “hollow” (i.e., [Formula Presented] and the radial ambipolar electric field can reverse to point inwards under certain conditions, reminiscent of observations in plasmas in toroidal devices at much higher temperatures.