Time variability in the X-ray emission of dM stars observed by EXOSAT.
Abstract
The authors studied the variability in the X-ray emission of 13 dMe stars observed with the LE+CMA onboard EXOSAT. The basic aim of this paper is to search for frequently occurring impulsive events with small energy releases in an effort to find out whether the "quiescent" X-ray emission from dM stars is really quiescent. The authors do not find, in any case, evidence for variability on short time scales in the quiescent emission of the sample stars, i.e., in periods during which no obvious large flare occurred. The authors also studied the non-quiescent (i.e., flaring) emission from the 13 stars in their sample and derived the cumulative distribution of the event frequency N(>E) vs. energy (E). The derived distribution implies that the most energetic events produce most of the non-quiescent X-ray emission.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- October 1988
- Bibcode:
- 1988A&A...205..197C
- Keywords:
-
- Exosat Satellite;
- M Stars;
- Red Dwarf Stars;
- Stellar Flares;
- X Ray Astronomy;
- Emission Spectra;
- Frequency Distribution;
- Light Curve;
- Stellar Coronas;
- Astrophysics