lyndonashmore, you are missing Papageno's point. An electron by itself cannot absorb a photon. It just doesn't happen. When electrons are in bound quantum states (i.e., bound to a nucleus) the atom can absorb the photon, causing the electron to "jump" to another state. When it returns to the ground state it emits a photon of equal energy to the original aborbed photon. That is how it works. IG plasma, by definition, is not full of bound electrons but rather free particles. A photon hitting an electron in the IG plasma causes a collision, Compton Scattering. The only way the photon loses energy is if its direction is changed as a result of the collision. There is no absorption or emission taking place.