Results from an extensive Einstein stellar survey.
Abstract
The preliminary results of the Einstein Observatory stellar X-ray survey are presented. To date, 143 soft X-ray sources have been identified with stellar counterparts, leaving no doubt that stars in general constitute a pervasive class of low-luminosity galactic X-ray sources. Stars along the entire main sequence, of all luminosity classes, pre-main sequence stars as well as very evolved stars have been detected. Early type OB stars have X-ray luminosities in the range 10 to the 31st to 10 to the 34th ergs/s; late type stars show a somewhat lower range of X-ray emission levels, from 10 to the 26th to 10 to the 31st ergs/s. Late type main-sequence stars show little dependence of X-ray emission levels upon stellar effective temperature; similarly, the observations suggest weak, if any, dependence of X-ray luminosity upon effective gravity. Instead, the data show a broad range of emission levels (about three orders of magnitude) throughout the main sequence later than F0.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 1981
- DOI:
- 10.1086/158797
- Bibcode:
- 1981ApJ...245..163V
- Keywords:
-
- Early Stars;
- Hertzsprung-Russell Diagram;
- Main Sequence Stars;
- Stellar Coronas;
- X Ray Sources;
- B Stars;
- Emission Spectra;
- O Stars;
- Stellar Gravitation;
- Stellar Luminosity;
- Stellar Temperature;
- White Dwarf Stars;
- Astronomy