The Eddington factor as the key to understand the winds of the most massive stars. Evidence for a Γ-dependence of Wolf-Rayet type mass loss

@article{Grafener2011TheEF,
  title={The Eddington factor as the key to understand the winds of the most massive stars. Evidence for a $\Gamma$-dependence of Wolf-Rayet type mass loss},
  author={Gotz Grafener and Jacco Vink and Alex de Koter and Norbert Langer},
  journal={Astronomy and Astrophysics},
  year={2011},
  volume={535},
  pages={14}
}
Context. The most massive stars are thought to be hydrogen-rich Wolf-Rayet stars of late spectral subtype (in the following WNh stars). The emission-line spectra of these stars are indicative of strong mass loss. In previous theoretical studies this enhanced mass loss has been attributed to their proximity to the Eddington limit. Aims. We investigate observed trends in the mass-loss properties of such young, very massive stars to examine a potential Γ-dependence, i.e., with respect to the… 
Wolf-Rayet stars in the Small Magellanic Cloud: I. Analysis of the single WN stars
Wolf-Rayet (WR) stars have a severe impact on their environments owing to their strong ionizing radiation fields and powerful stellar winds. Since these winds are considered to be driven by radiation
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Context. Massive stars, although being important building blocks of galaxies, are still not fully understood. This especially holds true for Wolf-Rayet (WR) stars with their strong mass loss, whose
Mass loss and the Eddington parameter: a new mass-loss recipe for hot and massive stars
Mass loss through stellar winds plays a dominant role in the evolution of massive stars. In particular the mass-loss rates of very massive stars (VMSs, $> 100\,M_{\odot}$) are highly uncertain. Such
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On the optically-thick winds of Wolf-Rayet stars
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