X-ray Observations of Binary and Single Wolf-Rayet Stars with XMM-Newton and Chandra
Abstract
We present an overview of recent X-ray observations of Wolf-Rayet (WR) stars with XMM-Newton and Chandra. These observations are aimed at determining the differences in X-ray properties between massive WR + OB binary systems and putatively single WR stars. A new XMM spectrum of the nearby WN8 + OB binary WR 147 shows hard absorbed X-ray emission (including the Fe Kα line complex), characteristic of colliding wind shock sources. In contrast, sensitive observations of four of the closest known single WC (carbon-rich) WR stars have yielded only non-detections. These results tentatively suggest that single WC stars are X-ray quiet. The presence of a companion may thus be an essential factor in elevating the X-ray emission of WC + OB stars to detectable levels.
- Publication:
-
Astrophysics and Space Science
- Pub Date:
- August 2006
- DOI:
- 10.1007/s10509-006-9082-3
- arXiv:
- arXiv:astro-ph/0511137
- Bibcode:
- 2006Ap&SS.304...97S
- Keywords:
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- Stars:Wolf-Rayet;
- Stars:X-rays;
- Astrophysics
- E-Print:
- To appear in conf. proceedings: Close Binaries in the 21st Century - New Opportunities and Challenges, eds. A. Gimenez, E. Guinan, P. Niarchos, S. Rucinski