Hostname: page-component-586b7cd67f-tf8b9 Total loading time: 0 Render date: 2024-11-29T20:58:54.204Z Has data issue: false hasContentIssue false

Theories for the Winds from Wolf Rayet Stars

Published online by Cambridge University Press:  14 August 2015

Joseph P. Cassinelli*
Affiliation:
University of Wisconsin-Madison

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 massive and fast winds of Wolf Rayet stars present a serious momentum problem for the line-driven wind theories that are commonly used to explain the fast winds of early type stars. It is perhaps possible for the winds to be driven by lines, if multiple scattering occurs and if there are a sufficient number of lines in the spectrum so that large fraction of the continuum is blocked by line opacity in the winds. Several other mechanisms are discussed, in particular two that rely on strong magnetic fields: a) Alfven wave driven wind models like those recently developed by Hartmann and MacGregor for late type supergiants and b) the “Fast Magnetic Rotator” model that was developed by Belcher and MacGregor for the winds from pre-main sequence stars. In either model, large magnetic fields (≈104 gauss) are required to drive the massive and fast winds of Wolf Rayet stars. Smaller fields might be possible if the multiple scattering line radiation force can be relied on to provide a final acceleration to terminal velocity.

Type
SESSION 3 — MASS-LOSS FROM WR STARS: OBSERVATIONS AND THEORY
Copyright
Copyright © Reidel 1982 

References

Abbott, D.C. 1980, Astrophys. J., 242, 1183.CrossRefGoogle Scholar
Abbott, D.C. 1977, Ph.D. thesis, University of Colorado.Google Scholar
Belcher, J.W. 1971, Astrophys. J., 168, 509.CrossRefGoogle Scholar
Belcher, J.W., and MacGregor, K.B. 1976, Astrophys. J., 210, 498.CrossRefGoogle Scholar
Cassinelli, J.P. 1971, Astrophys. Letters, 8, 105.Google Scholar
Castor, J. I., Abbott, D.C., and Klein, R.I. 1976, in Physique des Mouvements dans les Atmospheres Stellaires , (eds. Cayrel, R., Steinberg, M., Paris: Cent. Nat. Rech. Sci.).Google Scholar
DeCampli, W.M. 1981, Astrophys. J., 244, 124.CrossRefGoogle Scholar
Hartmann, L. and MacGregor, K.B. 1980, Astrophys. J., 242, 260.CrossRefGoogle Scholar
Hartmann, L. and MacGregor, K.B. 1982, preprint.Google Scholar
Hearn, A.G. 1975, Astron. Astrophys., 40, 277.Google Scholar
Hundhausen, A.J. 1973, Journ. Geophys. Res., 78, 2035.CrossRefGoogle Scholar
Jacques, S.A. 1978, Astrophys. J., 226, 632.CrossRefGoogle Scholar
Lamers, H.J.G.L.M. and Snow, T.P. 1981, preprint.Google Scholar
Leer, E. and Holzer, T.B. 1980, Journ. Geophys. Res., 85.Google Scholar
Lucy, L.B. and Solomon, P.M. 1970, Astrophys. J., 159, 879.CrossRefGoogle Scholar
Lucy, L.B. and White, R. 1980, Astrophys. J., 241, 300.CrossRefGoogle Scholar
Nerney, S. 1980, Astrophys. J., 242, 723.CrossRefGoogle Scholar
Panagia, N. and Macchetto, F. 1981 in IAU COLL. No. 59 on “Effects of Mass Loss in Stellar Evolution”.Google Scholar
Sanders, W.T., Cassinelli, J.P. and van der Hucht, K.A. 1982, these proceedings.Google Scholar
VanBlerkom, D. 1973 in IAU Symp. #49, Wolf Rayet and High-Temperature Stars , (eds. Bappu, M.K.V. and Sahade, J., D. Reidel: Dordrecht) p. 165.CrossRefGoogle Scholar
van der Hucht, K.A., Cassinelli, J.P., Wesselius, P.R. and Wu, C.C. 1979, Astron. Astrophys. Suppl, 38, 279.Google Scholar
Waldron, W.L. 1981, Ph.D. thesis, University of Wisconsin.Google Scholar
Willson, L.A. and Hill, S.J. 1979, Astrophys. J., 228, 854.CrossRefGoogle Scholar