Stellar Coronae at the End of the Main Sequence: A ROSAT Survey of the Late M Dwarfs
Abstract
We present X-ray data, both detections and upper limits, from the ROSAT all-sky survey for most known M dwarfs later than type M5, as well as from selected ROSAT pointed observations of some of these stars. We compare these data with similar data for early M dwarfs in an attempt to probe the nature of the magnetic dynamo and coronal heating mechanism for the very late M dwarfs, which are presumably totally convective. Our results indicate that late M dwarfs can have coronae which are just as active as those for the early M dwarfs and that coronal heating efficiency for 'saturated' stars does not drop at spectral type M6.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- June 1993
- DOI:
- 10.1086/172755
- Bibcode:
- 1993ApJ...410..387F
- Keywords:
-
- Dwarf Stars;
- M Stars;
- Main Sequence Stars;
- Rosat Mission;
- Spaceborne Astronomy;
- Stellar Coronas;
- Astronomical Catalogs;
- Light Curve;
- Sky Surveys (Astronomy);
- X Ray Astronomy;
- X Ray Sources;
- Astrophysics;
- STARS: CORONAE;
- STARS: LATE-TYPE;
- X-RAYS: STARS