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Observations Versus Atmospheric Models of WR Stars

Published online by Cambridge University Press:  03 August 2017

Werner Schmutz*
Affiliation:
Joint Institute for Laboratory Astrophysics University of Colorado and National Institute of Standards and Technology Boulder, CO 80309-0440, USA

Abstract

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Current knowledge of Wolf-Rayet continua is reviewed and observed continuum energy distributions are compared with model predictions. Good agreement is found. For WN stars a large range in intrinsic color is found for each subclass and the so far unexplained large range in the observed reddening-free continuum indices can be understood on the basis of atmospheric models. The strength of the continuum discontinuities determines the value of the index. Because of severe blending by the emission lines in WC spectra it can not be decided whether the intrinsic colors of WC stars of a given spectral type vary over a range of values or whether all stars of a given spectral type are similar. The reliability of model calculations for Wolf-Rayet stars is further tested by comparing observed and predicted correlations of helium line strengths. Satisfactory agreement is found for the Kiel/JILA models but not for the Bhatia-Underhill models. Methods used to determine the reddening due to interstellar extinction are reviewed and their accuracies estimated.

Type
Session II. Atmospheres
Copyright
Copyright © Kluwer 1991 

References

Allen, D. A., Swings, J. P., and Harvey, P. M. 1972, Astr. Ap., 20, 333.Google Scholar
Barlow, M. J., Smith, L. J., and Willis, A. J. 1981, M.N.R.A.S., 196, 101.CrossRefGoogle Scholar
Bhatia, A. K., and Underhill, A. B. 1986, Ap. J. Suppl., 60, 323.CrossRefGoogle Scholar
Cassinelli, J. P., et al. 1981, Ap. J., 250, 677.CrossRefGoogle Scholar
Conti, P. S., and Massey, P. 1989, Ap. J., 337, 251.CrossRefGoogle Scholar
Conti, P. S., Massey, P., and Vreux, J. M. 1990, Ap. J., 354, 359.CrossRefGoogle Scholar
Conti, P. S., and Morris, P. W. 1990, A. J., 99, 898.CrossRefGoogle Scholar
Cohen, M., Barlow, M. J., and Kuhi, L. V. 1975, Astr. Ap., 40, 291.Google Scholar
Ekberg, O. 1975a, Phys. Scripta, 11, 23.CrossRefGoogle Scholar
Ekberg, O. 1975b, Phys. Scripta, 12, 42.CrossRefGoogle Scholar
Hamann, W.-R., and Schmutz, W. 1987, Astr. Ap., 174, 173.Google Scholar
Hamann, W.-R., Schmutz, W., and Wessolowski, U. 1988, Astr. Ap., 194, 190.Google Scholar
Hillier, D. J. 1987a, Ap. J. Suppl., 63, 947.CrossRefGoogle Scholar
Hillier, D. J. 1987b, Ap. J. Suppl., 63, 965.CrossRefGoogle Scholar
Hillier, D. J. 1989, Ap. J., 347, 392.CrossRefGoogle Scholar
Howarth, I. D., and Phillips, A. P. 1986, M.N.R.A.S., 222, 809.CrossRefGoogle Scholar
Koenigsberger, G. 1988 Rev. Mex. Astr. Astrof., 16, 75.Google Scholar
Koenigsberger, G., and Auer, L. H. 1985 Ap. J., 297, 255.CrossRefGoogle Scholar
Koesterke, L., Hamann, W.-R., Schmutz, W., and Wessolowski, U. 1990, in preparation.Google Scholar
Long, K. S., and White, R. L. 1980, Ap. J. (Letters), 239, L65.CrossRefGoogle Scholar
Massey, P. 1984, Ap. J., 281, 789.CrossRefGoogle Scholar
McCandliss, S. R. 1988, Ph. D. Thesis, University of Colorado.Google Scholar
Monderen, P., De Loore, C. W. H., van der Hucht, K. A., and van Genderen, A. M. 1988, Astr. Ap., 195, 179.Google Scholar
Nugis, T., and Sapar, A. 1985, Sov. Astr. Let., 11, 188.Google Scholar
Pollock, A. M. T. 1987, Ap. J., 320, 283.CrossRefGoogle Scholar
Schmutz, W. 1988, in Lecture Notes in Physics Vol. 305, IAU Colloquium 108, p. 133.CrossRefGoogle Scholar
Schmutz, W., Hamann, W.-R., and Wessolowski, U. 1989, Astr. Ap., 210, 236.Google Scholar
Schmutz, W., and Vacca, W. D. 1990, Astr. Ap. Suppl., in preparation.Google Scholar
Schmutz, W., Vogel, M., Hamann, W.-R., and Wessolowski, U. 1990, Astr. Ap., in preparation (model fluxes are available from the author).Google Scholar
Smith, L. J., and Willis, A. J. 1983, Astr. Ap. Suppl., 54, 229.Google Scholar
Smith, L. F. 1968, M.N.R.A.S., 140, 409.CrossRefGoogle Scholar
Smith, L. F., Shara, M. M., and Moffat, A. F. J. 1990, Ap. J., 348, 471.CrossRefGoogle Scholar
St-Louis, N., et al. 1989, Astr. Ap., 226, 249.Google Scholar
Torres, A. V., and Massey, P. 1987, Ap. J. Suppl., 65, 459.CrossRefGoogle Scholar
Torres-Dodgen, A. V., and Massey, P. 1988, A. J., 96, 1076.CrossRefGoogle Scholar
Vacca, W. D., and Torres-Dodgen, A. V. 1990, Ap. J. Suppl., 73, in press.CrossRefGoogle Scholar
van der Hucht, K. A., et al. 1985, in Birth and Evolution of Massive Stars and Stellar Groups, ed. Boland, W. and van Woerden, H. (Dordrecht: Reidel), p. 167.CrossRefGoogle Scholar
van Genderen, A. M., van der Hucht, K. A., and Larsen, I. 1990, Astr. Ap., 229, 123.Google Scholar
Vreux, J. M., Andrillat, Y., and Biemont, E. 1990, Astr. Ap., preprint.Google Scholar
Vreux, J. M., Dennefeld, M., and Andrillat, Y. 1983, Astr. Ap. Suppl., 54, 437.Google Scholar
Vreux, J. M., Dennefeld, M., Andrillat, Y., and Rochowicz, K. 1989, Astr. Ap. Suppl., 81, 353.Google Scholar
Westerlund, B. E. 1966, Ap. J., 145, 724.CrossRefGoogle Scholar
White, R. L., and Long, K. S. 1986, Ap. J., 310, 832.CrossRefGoogle Scholar
Willis, A. J., van der Hucht, K. A., Conti, P. S., and Garmany, C. D. 1986, Astr. Ap. Suppl., 63, 417.Google Scholar