On the Role of the WNH Phase in the Evolution of Very Massive Stars: Enabling the LBV Instability with Feedback

@article{Smith2008OnTR,
  title={On the Role of the WNH Phase in the Evolution of Very Massive Stars: Enabling the LBV Instability with Feedback},
  author={Nathan Smith and Peter S. Conti},
  journal={The Astrophysical Journal},
  year={2008},
  volume={679},
  pages={1467 - 1477}
}
We propose the new designation “WNH” for luminous Wolf-Rayet (WR) stars of the nitrogen sequence with hydrogen in their spectra. These have been commonly referred to as WNL stars (WN7h, for example), but this new shorthand avoids confusion because there are late-type WN stars without hydrogen and early-type WN stars with hydrogen. Clearly differentiating WNH stars from H-poor WN stars is critical when discussing them as potential progenitors of Type Ib/c supernovae and gamma-ray bursts—the… 

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