Hostname: page-component-78c5997874-t5tsf Total loading time: 0 Render date: 2024-11-08T07:28:29.722Z Has data issue: false hasContentIssue false

Theoretical Results on WR Instabilities

Published online by Cambridge University Press:  03 August 2017

André Maeder
Affiliation:
Geneva Observatory CH-1290 Sauverny, Switzerland
Gérard Schaller
Affiliation:
Geneva Observatory CH-1290 Sauverny, Switzerland

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The instabilities of WR stars are discussed in the framework of both the quasi-adiabatic and non-adiabatic methods. We show that a very careful treatment of stellar opacities is necessary. Both methods show that WR stars, with little or no H left, are vibrationally unstable in the fundamental radial mode due to the ε-mechanism, confirming earlier results by Maeder (1985). Thus, from the point of view of stability, WR stars are fundametally different from O stars. Our new analysis also supports our previous view that WR stars evolve, keeping at the edge of vibrational instability.

Type
Session III. Intrinsic Variability
Copyright
Copyright © Kluwer 1991 

References

Boury, A., Ledoux, P.: 1965, Ann. Astrophys. 28, 353 Google Scholar
Cox, A.N., Cahn, J.H.: 1988, Astrophys. J. 326, 804 Google Scholar
Kirbiyik, H., Bertelli, G., Chiosi, C.: 1984, in 25th Liège Colloquium, Ed. Noels, A., Gabriel, M., p. 126 Google Scholar
Maeder, A.: 1981, Astron. Astrophys. 99, 97 Google Scholar
Maeder, A.: 1983, Astron. Astrophys. 120, 113 Google Scholar
Maeder, A.: 1985, Astron. Astrophys. 147, 300 Google Scholar
Noels-Grötsch, A.: 1967, Ann. Astrophys. 30, 349 Google Scholar
Noels, A., Magain, E.: 1984, Astron. Astrophys. 139, 341 Google Scholar
Noels, A., Masereel, C.: 1982, Astron. Astrophys. 105, 293 Google Scholar
Noels, A., Scuflaire, R.: 1986, Astron. Astrophys. 161, 125 Google Scholar
Simon, R.: 1957, Bull. Acad. Roy. Belgique, Cl. Sci. 43, 610 Google Scholar
Simon, N.R., Stothers, R.: 1969, Astrophys. J. 155, 247 Google Scholar
Simon, N.R., Stothers, R.: 1970, Astron. Astrophys. 6, 183 Google Scholar
Stellingwerf, R.F.: 1975, Astrophys. J. 195, 441 Google Scholar
Stothers, R., Simon, N.R.: 1970, Astrophys. J. 160, 1019 Google Scholar