3-minute oscillations of the polarized radio emission of local sources on the sun.
Abstract
Consideration is given to the 3-min oscillations of circularly polarized radio-emission of the local source associated with sunspot group SD No. 401. Observations were carried out on the RT-22 radiotelescope at the Crimean Astrophysical Observatory during August 15-21, 1980 at a wavelength of 2.25 cm. The modulation depth of the polarized radio-emission flux density varies from zero to several percent with a period greater than 20 min. These oscillations are less distinct in the total intensity. The flux densities, the degree of polarization, and the angular dimensions of the source are determined. The dynamics of the power spectra of the local source oscillations is studied during the passage of the sunspot group over the solar disk. It is shown that the oscillatory processes in both the total intensity and in the source's polarized radio-emission develop and fade during a time span of 0.5-1.0 days. The appearance of a second modulation of 2-min to 6-min oscillations is explained by MHD-wave passage across the coronal condensation.
- Publication:
-
Izvestiya Ordena Trudovogo Krasnogo Znameni Krymskoj Astrofizicheskoj Observatorii
- Pub Date:
- 1985
- Bibcode:
- 1985IzKry..73...53A
- Keywords:
-
- Circular Polarization;
- Emission Spectra;
- Radio Spectra;
- Solar Oscillations;
- Sunspots;
- Magnetohydrodynamic Waves;
- Polarimetry;
- Power Spectra;
- Radiant Flux Density;
- Radio Telescopes;
- Stellar Spectrophotometry;
- Solar Physics;
- Periods:Solar Radio Radiation;
- Polarization:Solar Radio Radiation;
- Solar Radio Radiation:Periods;
- Solar Radio Radiation:Polarization