Stochastic diffusion of photons in an unstable turbulent and magnetized plasma.
Abstract
A Fokker-Planck equation describing the generation and the diffusion of plasmons in the presence of a low frequency turbulence has been obtained using the so-called 'Liouville equation' technique. The diffusion coefficients have been evaluated by supposing that the turbulence has a Gaussian spectrum. The application of the diffusion equation to both electrostatic and electromagnetic waves propagating in a turbulent medium is discussed. For cyclotron harmonic waves the conditions under which such waves may propagate in presence of MHD fluctuations are obtained. A rough analytical solution of the diffusion equation has also been given, which shows that the presence of fluctuations gives rise to asymptotic values for the frequency and angular bandwidths of the radiation produced in a turbulent medium. It is shown that such values are consistent with the observed frequency and angular bandwidths of type I solar radio bursts.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- March 1979
- Bibcode:
- 1979A&A....73..292M
- Keywords:
-
- Fokker-Planck Equation;
- Photons;
- Plasma Diffusion;
- Plasma Turbulence;
- Solar Magnetic Field;
- Stochastic Processes;
- Cyclotron Radiation;
- Electromagnetic Wave Transmission;
- Electrostatic Waves;
- Liouville Equations;
- Magnetohydrodynamic Stability;
- Plasmons;
- Solar Corona;
- Solar Radio Bursts;
- Plasma Physics;
- Plasma:Solar Radio Bursts;
- Plasma:Wave Propagation