Hostname: page-component-586b7cd67f-dlnhk Total loading time: 0 Render date: 2024-11-24T17:27:52.746Z Has data issue: false hasContentIssue false

Status of Wolf-Rayet models

Published online by Cambridge University Press:  07 August 2017

D. J. Hillier*
Affiliation:
Department of Physics and Astronomy, University of Pittsburgh, 3941 O'Hara Street, Pittsburgh, PA 15260, U.S.A.

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.

In the last decade there has been a tremendous advance in our understanding of the atmospheres and stellar winds of Wolf-Rayet (WR) stars. This has arisen through improved observations, and through the application of extensive radiative transfer codes which has allowed us to model some of the complex processes occurring in WR envelopes. Present models are able to simultaneously treat detailed atomic models for H, He, C, N, O and Si. In the near future we will be able to treat Fe, and to more accurately treat the formidable problem of non-LTE line-blanketing. In this review we address current limitations in modeling the extended atmospheres of WR atmospheres. These limitations fall into two classes — those reflecting our inability to accurately compute the “Standard Model”, and those referring to assumptions in the “Standard Model” that need to be relaxed. Under the first category we include inaccuracies in the atomic data, the neglect of line-blanketing in the model calculations, and the inability of the present generation of models to compute the velocity law. Under the second category we include the assumption of spherical geometry, the assumption of homogeneity, the neglect of rotation, and the influence of X-rays arising from shocks in the stellar wind.

Type
Session II - Model atmospheres for single Wolf-Rayet stars
Copyright
Copyright © Kluwer 1995 

References

Aldrovandi, S.M.V., Pequignot, D. 1973, A&A 25, 137 Google Scholar
Aldrovandi, S.M.V., Pequignot, D. 1976, A&A 47, 321 Google Scholar
Baum, E., Hamann, W.-R., Koesterke, L., Wessolowski, U. 1992, A&A 266, 402 Google Scholar
Bjorkman, J.E., Cassinelli, J.P. 1993, ApJ 409, 429 Google Scholar
Brown, J.C., McLean, I.S. 1977, A&A 57, 141 Google Scholar
Crowther, P.A, Hillier, D.J., Smith, L.J. 1994a, A&A in press Google Scholar
Crowther, P.A, Hillier, D.J., Smith, L.J. 1994b, A&A in press Google Scholar
Crowther, P.A, Smith, L.J., Hillier, D.J., Schmutz, W. 1994d, A&A in press Google Scholar
Cunto, W., Mendoza, C. 1992, Rev. Mexicana Astron. Astrophys. 23, 107 Google Scholar
Esteban, C., Smith, L.J., Vilchez, J.M., Clegg, R.E.S. 1993, A&A 272, 299 Google Scholar
Gayley, K.G., Owocki, S.P., Cranmer, S.R. 1994, ApJ submitted Google Scholar
Hamann, W.R. 1985, A&A 148, 364 Google Scholar
Hamann, W.-R. 1994, in: Vanbeveren, D., van Rensbergen, W. & de Loore, C. (eds.), Evolution of Massive Stars: A Confrontation between Theory and Observation (Dordrecht: Kluwer), p. 237 CrossRefGoogle Scholar
Hamann, W.-R., Koesterke, L., Wessolowski, U. 1993, A&A 274, 397 Google Scholar
Hillier, D.J. 1990a, in: Garmany, C. (ed.), Intrinsic Properties of Hot Luminous Stars, ASP Conf. Series 7, p. 340 Google Scholar
Hillier, D.J. 1990b, A&A 231, 116 Google Scholar
Hillier, D.J. 1991a, A&A 247, 455 Google Scholar
Hillier, D.J. 1991b in: Crivellari, L., Hubeny, I. & Hummer, D.G. (eds.), Stellar Atmospheres: Beyond Classical Models, NATO ASI Series C341 (Kluwer: Dordrecht), p. 317 Google Scholar
Hillier, D. J. 1994a, A&A (in press) Google Scholar
Hillier, D.J., Kudritzki, R.P., Pauldrach, A.W., Baade, D., Cassinelli, J.P., Puls, J., Schmitt, J.H.M.M. 1993, A&A 276, 117 Google Scholar
Koesterke, L., Hamann, W.-R., Kosmol, P. 1992, A&A 255, 490 Google Scholar
Lucy, L.B., Abbott, D.C. 1993, ApJ 405, 738 Google Scholar
Mazzali, P.A. 1990, A&A 238, 191 Google Scholar
Mihalas, D., Hummer, D.G. 1973, ApJ 179, 827 CrossRefGoogle Scholar
Najarro, F., Hillier, D.J., Kudritzki, R.P., Krabbe, A., Genzel, R., Lutz, D., Drapatz, D., Geballe, T.R. 1994, A&A 285, 573 Google Scholar
Nussbaumer, H., Storey, P.J. 1983, A&A 126, 75 Google Scholar
Nussbaumer, H., Storey, P.J. 1984, A&A Suppl. 56, 293 Google Scholar
Owocki, S.P., Castor, J.I., Rybicki, G.B. 1988, ApJ 335, 914 Google Scholar
Owocki, S.P., Cranmer, S.R., Blondin, J.M. 1994, ApJ 424, 887 CrossRefGoogle Scholar
Pauldrach, A.W.A., Kudritzki, R.P., Puls, J., Butler, K., Hunsiger, J. 1994, A&A 283, 525 Google Scholar
Pollock, A.M.T. 1987, ApJ 320, 283 CrossRefGoogle Scholar
Rybicki, G.B. 1991 in: Crivellari, L., Hubeny, I. & Hummer, D.G. (eds.), Stellar Atmospheres: Beyond Classical Models, NATO ASI Series C341 (Kluwer: Dordrecht), p. 1 Google Scholar
Schmutz, W. 1990, in: Garmany, C. (ed.), Intrinsic Properties of Hot Luminous Stars, ASP Conf. Series 7, p. 117 Google Scholar
Schmutz, W. 1991, in: Crivellari, L., Hubeny, I. & Hummer, D.G. (eds.), Stellar Atmospheres: Beyond Classical Models, NATO ASI Series C341 (Kluwer: Dordrecht), p. 191 Google Scholar
Schmutz, W. 1994a, in: Vanbeveren, D., van Rensbergen, W. & de Loore, C. (eds.), Evolution of Massive Stars: A Confrontation between Theory and Observation (Dordrecht: Kluwer), p. 253 Google Scholar
Schulte-Ladbeck, , Clayton, G.C., Hillier, D.J., Harries, T.J., Howarth, I.D. 1994, ApJ in press (July) Google Scholar
Schulte-Ladbeck, R.E., Meade, M.R., Hillier, D.J., 1992 in: Drissen, L., Leitherer, C. & Nota, A. (eds.), Nonisotropic and Variable Outflows from Stars, ASP Conf. Series 22, p. 118 Google Scholar
Seward, F.D., Forman, W.R., Giacconi, R., Griffiths, R.E., Harnden, F.R., Jones, C., Pye, J.P. 1979, ApJ (Letters) 234, L55 Google Scholar
Springmann, U. 1994, A&A in press Google Scholar
Shull, J.M., Van Steenberg, M.E. 1985, ApJ 294, 599 Google Scholar
Wood, K., Brown, J.C., Fox, G.K. 1993, A&A 271, 492 Google Scholar