Propagation and absorption of electromagnetic waves in fully relativistic plasmas
Abstract
The propagation and absorption of electromagnetic waves in a relativistic Maxwellian plasma are investigated by solving the uniform plasma dispersion relation. Both the Hermitian and the antiHermitian parts of the plasma conductivity tensor sigma are calculated relativistically. The Bessel functions occurring in sigma are not expanded, and many cyclotron harmonic terms are included at high temperatures. The dispersion relation is solved numerically for perpendicular propagation, k (parallel) = 0, where the relativistic effects are maximum and are not masked by Doppler broadening, which has been more thoroughly investigated. It is found that relativistic broadening has a substantial effect on wave dispersion, shifting the extraordinary mode righthand cutoff and the upper hybrid resonance to a higher magnetic field with increasing temperature. Above a critical temperature the cutoff disappears entirely. There is a broad range of temperatures, 20 keV approximately less than T sub e approximately less than 500 keV, for which the wave number k perpendicular) differs significantly from both the cold plasma value and the vacuum value. This has important implications for ray tracing in relativistic plasmas. Wave damping rates are calculated and compared to results from a previous formulation using the Poynting theorem, in which only the Hermitian part of sigma is calculated relativistically.
 Publication:

Unknown
 Pub Date:
 May 1984
 Bibcode:
 1984paew.rept.....B
 Keywords:

 Electromagnetic Absorption;
 Plasma Conductivity;
 Relativistic Plasmas;
 Wave Propagation;
 Bessel Functions;
 Plasma Temperature;
 Poynting Theorem;
 Relativistic Effects;
 Temperature Effects;
 Wave Dispersion;
 Plasma Physics