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Quantitative Spectroscopy of Wolf-Rayet Stars

Published online by Cambridge University Press:  12 April 2016

W. Schmutz
W. Schmutz*
Affiliation:
Institut für Theoretische Physikund Sternwarte derUniversität KielOlshausenstrasse, D-2300 Kiel l, Federal Republic of Germany

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Advances in theoretical modeling of rapidly expanding atmospheres in the past few years made it possible to determine the stellar parameters of the Wolf-Rayet stars. This progress is mainly due to the improvement of the models with respect to their spatial extension: The new generation of models treat spherically-symmetric expanding atmospheres, i.e. the models are one-dimensional. Older models describe the wind by only one representative point. The older models are in fact ‘core-halo’ approximations. They have been introduced by Castor and van Blerkom (1970), and were extensively employed in the past (cf. e.g. Willis and Wilson, 1978; Smith and Willis, 1982). First results from new one-dimensional model calculations are published by Hillier (1984), Schmutz (1984), Hamann (1985), Hillier (1986), and Schmutz et al. (1987a); more detailed results are presented by Schmutz and Hamann (1986), Hamann and Schmutz (1987), Hillier (1987a,b), Wessolowski et al. (1987), Hillier (1987c) and Hamann et al. (1987). These results demonstrate that the step from zero- to one-dimensional calculations is essential. The important point is that the complicated interrelation between NLTE-level populations and radiation field is treated adequately (Schmutz and Hamann, 1986; Hillier, 1987). For this interrelation it is crucial to model consistently not only the line-formation region, but also the layers where the continuum is emitted. In fact, it is the core-halo approximation that causes the one-point models to fail in certain aspects.

Type
Part II. Mass-Losing Stars in Different Stages of Evolution
Information
International Astronomical Union Colloquium , Volume 108: Atmospherics Diagnostics of Stellar Evolution: Chemical Peculiarity, Mass Loss, and Explosion , 1988 , pp. 133 - 140
Copyright
Copyright © Springer-Verlag 1988

References

Castor, J.I., van Bierkom, D.: 1970, Astrophys. J. 161, 485 CrossRefGoogle Scholar
Conti, P.S., Germany, C.D., de Loore, C., Vanbeveren, D.: 1983, Astropys. J. 274, 302 Google Scholar
Hamann, W.-R.: 1985, Astron. Astrophys. 145, 443 Google Scholar
Hamann, W.-R.: 1986, Astron. Astrophys. 160, 347 Google Scholar
Hamann, W.-R., Schmutz, W.: 1987, Astron. Astrophys. 174, 173 Google Scholar
Hamann, W.-R., Schmutz, W., Wessolowski, U.: 1987, these proceedings and Astron. Astrophys. (in press)Google Scholar
Humphreys, R.M.: 1978, Astrophys. J. Suppl. 38, 309 CrossRefGoogle Scholar
Hillier, D.J.: 1984, Astrophys. J. 280, 744 Google Scholar
Hillier, D.J.: 1986, in ‘Luminous Stars and Associations in Galaxies’, de Loore, C.W.H., Willis, A.J., Laskarides, P. (eds.), IAU Symp. 116, 261 Google Scholar
Hillier, D.J.: 1987a, Astrophys. J. Suppl. 63, 947 CrossRefGoogle Scholar
Hillier, D.J.: 1987b, Astrophys. J. Suppl. 63, 965 Google Scholar
Hillier, D.J.: 1987c, Astrophys. J. submittedGoogle Scholar
Hiltner, W.A., Schild, R.E.: 1966, Astrophys. J. 143, 770 Google Scholar
Maeder, A.: 1982, in ‘Wolf-Rayet Stars: Observations, Physics, Evolution’ de Loore, C.W.H., Willis, A.J. (eds.), IAU Symp. 99, 405 Google Scholar
Maeder, A.: 1987, Astron. Astrophys. 178, 159 Google Scholar
Maeder, A., Meynet, G.: 1987, Astron. Astrophys. 182, 243 Google Scholar
Pauldrach, A., Puls, J., Hummer, D.G., Kudritzki, R.: 1985, Astron. Astrophys. 148, L1 Google Scholar
Schild, H., Maeder, A.: 1984, Astron. Astrophys. 136, 237 Google Scholar
Schmutz, W.: 1984, in ‘Observational Tests of the Stellar Evolution Theory’, Maeder, A., Renzini, A. (eds.), IAU Symp. 105, 269 CrossRefGoogle Scholar
Schmutz, W., Hamann, W.-R.: 1986, Astron. Astrophys. Letter 166, L11.Google Scholar
Schmutz, W., Hamann, W.-R., Wessolowski, U.: 1987a, in ‘Circumstellar Matter’, Appenzeller, I., Jordan, C. (eds.), IAU Symp. 122, 461 CrossRefGoogle Scholar
Schmutz, W., Hamann, W.-R., Wessolowski, U.: 1987b, these proceedingsGoogle Scholar
Schmutz, W., Hamann, W.-R., Wessolowski, U.: 1987b,c, these proceedings and Astron. Astrophys. submittedGoogle Scholar
Smith, L.J., Willis, A.J.: 1982, Monthly Notices Roy. Astron. Soc. 201, 451 CrossRefGoogle Scholar
Walborn, N.R.: 1974, Astrophys. J. 189, 269 Google Scholar
Wessolowski, U., Schmutz, W., Hamann, W.-R.: 1987, Astron. Astrophys. (in press)Google Scholar
Willis, A.J., Wilson, R.: 1978, Monthly Notices Roy. Astron. Soc. 182, 897 Google Scholar
Wright, A.E., Barlow, M.J.: 1975, Monthly Notices Roy. Astron. Soc. 170, 41 Google Scholar