X-RAY EMISSION FROM NITROGEN-TYPE WOLF–RAYET STARS

@article{Skinner2009XRAYEF,
  title={X-RAY EMISSION FROM NITROGEN-TYPE WOLF–RAYET STARS},
  author={Stephen L. Skinner and Svetozar A. Zhekov and Manuel G{\"u}del and Werner K. Schmutz and Kimberly R. Sokal},
  journal={The Astronomical Journal},
  year={2009},
  volume={139},
  pages={825 - 838}
}
We summarize new X-ray detections of four nitrogen-type Wolf–Rayet (WR) stars obtained in a limited survey aimed at establishing the X-ray properties of WN stars across their full range of spectral subtypes. None of the detected stars is so far known to be a close binary. We report Chandra detections of WR 2 (WN2), WR 18 (WN4), and WR 134 (WN6), and an XMM-Newton detection of WR79a (WN9ha). These observations clearly demonstrate that both WNE and WNL stars are X-ray sources. We also discuss… 
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