Hello,

I am trying to understand how the ionization mechanism of a substance/element will influence the color of the plasma that it produces. In particular, I am curious about the plasma produced in space electric thrusters (gridded ion thrusters, Hall thrusters, Pulsed Plasma thrusters) with different propellants (noble gases and halogens). Can you recommend any bibliography (book, published articles that deal with this topic?

Thank you in advance.