6 centimeter observations of solar active regions with 6" resolution.
Abstract
We have used the Westerbork Synthesis Radio Telescope for observations of solar active regions at 6 cm during 1974 May 8-10. The particular problems of using a sidereal instrument for solar observations are discussed. Maps of total intensity and circular polarization were obtained for four active regions with sunspots and a plage region; the linear polarization was below the noise limit. The brightest components of the 6 cm emission are associated with sunspots, while weaker components are associated with the plage magnetic fields, both longitudinal and transverse. An inversion of the sense of circular polarization was observed in the preceding part of a region with bipolar magnetic-field structure, about two days after the region passed through the central meridian. Nine bursts were also observed, and their one-dimensional positions with respect to the associated active regions are given.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 1977
- DOI:
- 10.1086/155155
- Bibcode:
- 1977ApJ...213..278K
- Keywords:
-
- Centimeter Waves;
- Circular Polarization;
- Faculae;
- Radio Astronomy;
- Solar Activity;
- Solar Radio Emission;
- Astronomical Maps;
- Brightness Temperature;
- Data Processing;
- Fine Structure;
- Solar Magnetic Field;
- Sunspots;
- Solar Physics