Difference between non-thermal and thermal ionized gases
A thermal plasma has its electrons and ions at the same temperature.  A raw plasma has hot electrons and cold ions from the vast difference in masses when microwave excited.  One way to thermalize is to run the plasma through a Helmholtz pair of coils with a strong uniform magnetic field parallel to plasma flow.  The low mass electrons tightly spiral around the parallel lines of force (that, of course, are not there), colliding with the nuclei to thermal equilibrium.

(That can sound a lot better than it works.)