Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-23T11:38:00.519Z Has data issue: false hasContentIssue false

Wolf-Rayet Wind Models from Hydrodynamic Model Atmospheres

Published online by Cambridge University Press:  01 December 2007

Götz Gräfener
Affiliation:
Institut für Physik, Universität Potsdam, Am Neuen Palais 10, 14469 Potsdam, Germany
Wolf-Rainer Hamann
Affiliation:
Institut für Physik, Universität Potsdam, Am Neuen Palais 10, 14469 Potsdam, Germany
Rights & Permissions [Opens in a new window]

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.

We present a parameter study of WR-type mass loss, based on the PoWR hydrodynamic model atmospheres. These new models imply that optically thick WR-type winds are generally formed close to the Eddington limit. This is demonstrated for the case of hydrogen rich WNL stars, which turn out to be extremely massive, luminous stars with progenitor masses above ≈ 80 M. We investigate the dependence of WR-type mass loss on various stellar parameters, including the metallicity Z. The results depend strongly on the L/M ratio, the stellar temperature T*, and the assumed wind clumping. For high L/M ratios, strong WR-type winds can be maintained down to very low Z. Even for primordial massive stars we predict considerable mass loss if their surfaces are self-enriched by primary elements.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2008

References

Barniske, A., Hamann, W.-R., & Gräfener, G. 2006, in: Lamers, H. J. G. L. M., Langer, N., Nugis, T., & Annuk, K. (eds.), Stellar Evolution at Low Metallicity: Mass Loss, Explosions, Cosmology (San Francisco: ASP) ASP Conf. Ser., 353, 243Google Scholar
Bonanos, A. Z., Stanek, K. Z., Udalski, A., et al. 2004, ApJL, 611, L33CrossRefGoogle Scholar
Castor, J. I., Abbott, D. C., & Klein, R. I. 1975, ApJ, 195, 157CrossRefGoogle Scholar
Figer, D. F. 2005, Nature, 434, 192CrossRefGoogle Scholar
Glatzel, W., & Kaltschmidt, H. O. 2002, MNRAS, 337, 743CrossRefGoogle Scholar
Gräfener, G., & Hamann, W.-R. 2005, A&A, 432, 633Google Scholar
Gräfener, G., & Hamann, W.-R. 2006, in: Lamers, H. J. G. L.M., Langer, N., Nugis, T., & Annuk, K. (eds.), Stellar Evolution at Low Metallicity: Mass Loss, Explosions, Cosmology (San Francisco: ASP) ASP Conf. Ser., 353, 171Google Scholar
Gräfener, G., & Hamann, W.-R. 2008, A&A, 482, 945Google Scholar
Gräfener, G., Koesterke, L., & Hamann, W.-R. 2002, A&A, 387, 244Google Scholar
Hamann, W.-R., & Gräfener, G. 2003, A&A, 410, 993Google Scholar
Hamann, W.-R., Gräfener, G., & Liermann, A. 2006, A&A, 457, 1015Google Scholar
Hamann, W.-R., & Koesterke, L. 1998, A&A, 335, 1003Google Scholar
Ishii, M., Ueno, M., & Kato, M. 1999, PASJ, 51, 417CrossRefGoogle Scholar
Koesterke, L., Hamann, W.-R., & Gräfener, G. 2002, A&A, 384, 562Google Scholar
Lamers, H. J. G. L. M., & Cassinelli, J. P. 1999, Introduction to Stellar Winds (Cambridge: Cambridge University Press)CrossRefGoogle Scholar
Langer, N., Hamann, W.-R., Lennon, M., et al. 1994, A&A, 290, 819Google Scholar
Martins, F., Hillier, D. J., Paumard, T., et al. 2008, A&A, 478, 219Google Scholar
Meynet, G., Ekström, S., & Maeder, A. 2006, A&A, 447, 623Google Scholar
Meynet, G., & Maeder, A. 2003, A&A, 404, 975Google Scholar
Moffat, A. F. J., Schnurr, O., Chené, A.-N., et al. 2007, Highlights of Astronomy, 14, 197Google Scholar
Nugis, T., & Lamers, H. J. G. L. M. 2002, A&A, 389, 162Google Scholar
Rauw, G., Vreux, J.-M., Gosset, E., et al. 1996, A&A, 306, 771Google Scholar
Schweickhardt, J., Schmutz, W., Stahl, O., et al. 1999, A&A, 347, 127Google Scholar
van der Hucht, K. A. 2001, New Astronomy Review, 45, 135CrossRefGoogle Scholar