Microwave polarization diagnostics of solar current sheets with transverse component of magnetic field Original Research Article

We present analitical solution to the problem of linear coupling of extraordinary (X) and ordinary (O) modes in a plasma current sheet with a transverse component of magnetic field. We indicate conditions of effective X-, O-mode coupling when the polarization features of microwaves having passed through the sheet differ essentially from those calculated in the geometrical optics approximation. We show that the corresponding polarization observations may give valuable data on the inhomogeneity and strength of the main and transverse components of magnetic field in the coupling region inside the sheet. The theory of mode coupling is applied to the calculations of the polarization features of solar microwave emission that turn out to be well interpreted if the proper current sheet stabilized by a weak transverse magnetic field is situated in the solar corona on the pathway of radio waves toward the Earth.