Synchrotron model for a radio burst of HR 1099.
Abstract
The radio spectrum of a long-lasting burst observed in the flaring star HR 1099, in the frequency range 1.4 GHz ≤ ν ≤ 15.5 GHz, is interpreted in terms of gyrosynchrotron radiation by mildly relativistic electrons. The observed flux at lower frequencies puts a firm lower limit on the dimension of the source, d ≡ 4-5 R*, making unlikely the hypothesis that the burst, at least at decimetric wavelengths, involves only a small portion of the stellar atmosphere. An electron density NR ∝ R-α in a uniform field B ≡ 100 G perfectly fits the observed points if α = 5.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- February 1985
- Bibcode:
- 1985A&A...143..226B
- Keywords:
-
- Flare Stars;
- Radio Bursts;
- Radio Spectra;
- Radio Stars;
- Stellar Activity;
- Synchrotron Radiation;
- Binary Stars;
- Electron Density (Concentration);
- Radiant Flux Density;
- Radiative Transfer;
- Stellar Flares;
- Stellar Models;
- Stellar Structure;
- Astrophysics