Detection of Linear Polarization in the Microwave Emission of Solar Active Regions
Abstract
We report the detection for the first time of linear polarization in the microwave emission above a Solar Active Region. The observations were made with the Westerbork Synthesis Radio Telescope, taking advantage of the very small bandwidth of a multichannel spectral line receiver. The intensity of the Stokes parameter U, measured at several points close to the line of zero circular polarization, shows a clear sinusoidal trend as a function of lambda2, in accordance to what is expected from Faraday rotation. From the measured period, reasonable values of integral NBLdr were derived. Such observations could present in the future a unique way to measure coronal magnetic fields above Active Regions.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- June 1994
- DOI:
- 10.1086/187396
- Bibcode:
- 1994ApJ...428L..73A
- Keywords:
-
- Faraday Effect;
- Linear Polarization;
- Magnetic Fields;
- Mapping;
- Microwave Emission;
- Radio Astronomy;
- Solar Corona;
- Bandwidth;
- Data Reduction;
- Dependence;
- Narrowband;
- Radio Telescopes;
- Wavelengths;
- Astrophysics;
- POLARIZATION;
- SUN: CORONA;
- SUN: RADIO RADIATION