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Properties of the Scenario for the Formation of WR Stars as Post-Red Supergiants

Published online by Cambridge University Press:  14 August 2015

André Maeder*
Affiliation:
Geneva Observatory, 1290 Sauverny, Switzerland

Extract

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Grids of evolutionary models for single stars in the range 9–120 M have been computed up to the end of the central C-burning phase with up-to-date stellar physics. In addition to other results these models allow us to study the main properties of the formation of WR stars as post-red supergiants (Maeder, 1981c). Three grids of models have been computed: one for constant mass evolution (grid A) and the other two (B and C) with mass loss. As there exists no unique parametrization representing, over the various spectral types, the mass loss rates as a function of basic stellar parameters, we have used mass loss rates fitted on the observations, applying different laws for a) OB stars, b) B-G supergiants, c) red supergiants (RSG) and d) WR stars. At a given luminosity, the rates in grid C are twice as large as in grid B and both grids encompass the central bulk of the observed mass loss rates.

Type
SESSION 5 — EVOLUTIONARY STATUS OF WOLF-RAYET STARS
Copyright
Copyright © Reidel 1982 

References

Barlow, M.J., Smith, L.J., Willis, A.J. 1981, MNRAS 196, 101.Google Scholar
Breysacher, J. 1981, private communication.Google Scholar
Conti, P. 1981, in Effects of Mass Loss on Stellar Evolution, ed. Chiosi, C. and Stalio, R. Google Scholar
Maeder, A. 1980, Astron. Astrophys. 92, 101.Google Scholar
Maeder, A. 1981a, Astron. Astrophys. 99, 97.Google Scholar
Maeder, A. 1981b, Astron. Astrophys. 101, 385; 1981c, in press.Google Scholar
Maeder, A., Lequeux, J., Azzopardi, M. 1980, Astron. Astrophys. 90, L17.Google Scholar
Turner, D.G. 1981, in IAU Symp. 105, ed. de Loore, C. and Willis, A., in press.Google Scholar