Equilibrium radiation in a plasma medium with spatial and frequency dispersion

TL;DR

This paper derives a general expression for equilibrium radiation in plasma media considering spatial and frequency dispersion, revealing deviations from classical Planck radiation due to plasma effects.

Contribution

It introduces a quantum electrodynamics-based approach to account for plasma's influence on equilibrium radiation through dielectric permittivity with dispersion and damping.

Findings

Spectral energy distribution differs from Planck radiation in plasma.

Derived a general relation incorporating spatial and frequency dispersion.

Results reduce to known expressions in the limit of infinitesimal damping.

Abstract

Examination of equilibrium radiation in plasma media shows that the spectral energy distribution of such radiation is different from the Planck equilibrium radiation. Using the approach of quantum electrodynamics the general relation for the spectral energy density of equilibrium radiation in a system of charged particles is found. The obtained result takes into account the influence of plasma on equilibrium radiation through the explicit transverse dielectric permittivity which takes into account spatial and frequency dispersion, as well as the finite collisional damping. For the limiting case of an infinitesimal damping the result coincides with the known expression.