X-Ray Emission from Wolf-Rayet Stars
Abstract
Seven bright Wolf-Rayet (WR) stars were observed with the Einstein X-ray observatory; four were detected. The 0.15-4 keV fluxes of the detected stars (and the upper limits for the others) are consistent with the ratio of X-ray to bolometric luminosities observed for other early-type stars. The X-ray spectra of WR stars are also similar to those of OB stars, with most of the photons emerging with energies less than 1 keV. These observations support the idea that X-ray emission in all hot stars is produced by shocks in the wind. The X-ray flux of one of the stars, HD 50896, varied by a factor of 2 within half an hour on two of the three days when it was observed. The possible origin of these variations is discussed; it is concluded that the companion of HD 50896 is either a black hole or a white dwarf remnant of a massive star.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 1986
- DOI:
- 10.1086/164736
- Bibcode:
- 1986ApJ...310..832W
- Keywords:
-
- Stellar Radiation;
- Stellar Winds;
- Wolf-Rayet Stars;
- X Ray Stars;
- Binary Stars;
- Black Holes (Astronomy);
- Companion Stars;
- Heao 2;
- Shock Waves;
- White Dwarf Stars;
- Astrophysics;
- SHOCK WAVES;
- STARS: EARLY-TYPE;
- STARS: WINDS;
- STARS: WOLF-RAYET;
- STARS: X-RAYS;
- X-RAYS: SOURCES