The Metallicity Dependence of Wolf-Rayet Mass Loss
Abstract
We produce models of early WN, WC, and WO stars as a function of metallicity Z using an analytic CAK-type approach. At log(Z / Z_sun) >= -2 both WN and WC stars have the approximate dependence Mdot \propto Z^{0.5}. For a WN wind the mass-loss rate drops rapidly below log(Z / Z_sun) = -2, and no wind solution can be found for log(Z / Z_sun) < -3. For WC and WO winds the mass-loss rate plummets in the range -3 <= log(Z / Z_sun) <= -2 and tends to flatten due to the self-enrichment of C and O to around 10^{-8} M_sun yr^{-1} for log(Z / Z_sun) <= -4. No significant difference in Mdot was found for WC versus WO stars at low metallicity.
Keywords
Cite
@article{arxiv.0711.0033,
title = {The Metallicity Dependence of Wolf-Rayet Mass Loss},
author = {A. J. Onifer and A. Heger and J. Abdallah},
journal= {arXiv preprint arXiv:0711.0033},
year = {2007}
}
Comments
2 pages, 2 figures, to be published in the proceedings of Hydrogen Deficient Stars, Tuebingen, Germany, Sept. 17-21, 2007