Compton Interaction of a Photon Gas with a Plasma

Abstract

The rate of energy transfer due to Compton collisions from a photon gas to a Maxwell electron gas is calculated to fourth order in the expansion parameters $\frac{k{T}_{e}}{m{c}^{2}}$ and $\frac{k{T}_{R}}{m{c}^{2}}$. The photon distribution is taken to be Planckian at a temperature ${T}_{R}$ not equal to the electron temperature ${T}_{e}$. It is found that the nonrelativistic expression is accurate only for $k{T}_{R}\ensuremath{\le}2.5$ keV and $k{T}_{e}\ensuremath{\le}20$ keV, while the fourth-order expression is accurate for $k{T}_{R}\ensuremath{\le}10$ keV and $k{T}_{e}\ensuremath{\le}80$ keV.