Polarization of decameter radio waves in a random circumsolar plasma. I. Mean stokes parameters

Abstract

The Stokes parameters of decameter radio waves propagating in the circumsolar plasma and solar corona were analyzed. It was shown that the circular polarization of solar decameter radio emission can be observed by spaced antennas. Distortions of the received polarization due to averaging of antenna aperture for large-size receiving antennas were evaluated. An explanation of the solar flares elliptical polarization is proposed. This polarization arises due to transformation of circularly polarized radio waves in linearly polarized ones if the circumsolar plasma and solar corona contains anisotropic fluctuations of the transverse magnetic field.