| Abstract: | Spectra of solar-flare active regions displaying peculiarities in their polarized radio emission observed on the RATAN-600
radio telescope at 2–16 GHz are considered. An appreciable dip of the circularly polarized emission (Stokes parameter V) in the middle of the microwave range (6–12 GHz), sometimes with a reversal of the sign of the polarization, is unusual.
In some cases, the ordinary emission also dominates at long microwave wavelengths. Expected peculiarities of the frequency
structure of microwave sources are calculated in simple models with loops in the form of hot and cool tori. Numerical calculations
of these spectra show that the above features of the polarized emission can be explained by the presence of a hot region in
the solar corona. It is shown that the parameters of the spectrum of the polarized emission can be used to determine the magnetic
field in this hot region and the product of the relative magnetic-field gradient and the loop thickness. |
