High-Resolution Chandra Spectroscopy of τ Scorpii: A Narrow-Line X-Ray Spectrum from a Hot Star

@article{Cohen2003HighResolutionCS,
  title={High-Resolution Chandra Spectroscopy of $\tau$ Scorpii: A Narrow-Line X-Ray Spectrum from a Hot Star},
  author={David H Cohen and Genevi{\`e}ve E. de Messi{\`e}res and J. J. Macfarlane and Nathan A. Miller and Joseph Patrick Cassinelli and Stanley P. Owocki and Duane A. Liedahl},
  journal={The Astrophysical Journal},
  year={2003},
  volume={586},
  pages={495-505}
}
Long known to be an unusual early-type star by virtue of its hard and strong X-ray emission, τ Scorpii poses a severe challenge to the standard picture of O-star wind-shock X-ray emission. The Chandra HETGS spectrum now provides significant direct evidence that this B0.2 star does not fit this standard wind-shock framework. The many emission lines detected with the Chandra gratings are significantly narrower than what would be expected from a star with the known wind properties of τ Sco… 
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