Condensed Matter Physics, 2009, vol. 12, No. 4, pp. 617-632
Photon kinetics in plasmas
(Moscow State Institute of Radioengineering, Electronics, and Automation (Technical University), Vernadsky Prospect, 78, 119454 Moscow, Russia)
(Universität Rostock, Institut für Physik, D-18051 Rostock, Germany)
We present a kinetic theory of radiative processes in many-component plasmas with relativistic electrons and nonrelativistic heavy particles. Using the non-equilibrium Green's function technique in many-particle QED, we show that the transverse field correlation functions can be naturally decomposed into sharply peaked (non-Lorentzian) parts that describe resonant (propagating) photons and off-shell parts corresponding to virtual photons in the medium. Analogous decompositions are obtained for the longitudinal field correlation functions and the correlation functions of relativistic electrons. We derive a kinetic equation for the resonant photons with a finite spectral width and show that the off-shell parts of the particle and field correlation functions are essential to calculate the local radiating power in plasmas and recover the results of vacuum QED. The plasma effects on radiative processes are discussed.
many-particle QED, nonequilibrium Green's functions, relativistic plasmas
52.20.-j, 52.25Dg, 52.38Ph, 52.25Os, 52.27Ny