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Stratified NLTE Model Atmospheres for Hot Stars

Published online by Cambridge University Press:  26 May 2016

Stefan Dreizler  and
Sonja L. Schuh
Stefan Dreizler
Affiliation:
Institut für Astronomie und Astrophysik, Universität Tübingen, Sand 1, D-72076 Tübingen
Sonja L. Schuh
Affiliation:
Institut für Astronomie und Astrophysik, Universität Tübingen, Sand 1, D-72076 Tübingen

Abstract

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In most stellar atmosphere models, a homogeneous chemical composition is assumed, which is a good approximation for many stars. With the absence of convection and mass–loss, however, gravitational settling can produce a chemical stratification gradient. Typical examples are white dwarfs. In hot stars this diffusion process is modified by the radiative acceleration, resulting in levitation of ions with large radiative cross sections. The status of our program for self-consistent stratified non-LTE model atmospheres is presented.

Type
Session A. Current Status of Modelling
Information
Symposium - International Astronomical Union , Volume 210: Modelling of Stellar Atmospheres , 2003 , pp. 33 - 43
Copyright
Copyright © Astronomical Society of the Pacific 2003 

References

Barstow, M. A., Fleming, T. A., & Diamond, C. J., et al. 1993, MNRAS, 264, 16 Google Scholar
Barstow, M. A., Dobbie, P. D., Holberg, J. B., Hubeny, I., & Lanz, T. 1997, MNRAS, 286, 58 CrossRefGoogle Scholar
Barstow, M. A., Bannister, N. P., Holberg, J. B., Hubeny, I., Bruhweiler, F. C., & Napiwotzki, R. 2001, MNRAS, 325, 1149 Google Scholar
Bradley, P., & Winget, D. 1994, ApJ, 430, 850 Google Scholar
Bruhweiler, F., & Kondo, Y. 1981, ApJ, 248, L123 CrossRefGoogle Scholar
Chayer, P., Fontaine, G., & Wesemael, F. 1989, in White Dwarfs, ed. Wegner, G., Springer, Berlin, p. 253 CrossRefGoogle Scholar
Chayer, P., Fontaine, G., & Wesemael, F. 1991, in White Dwarfs, eds. Vauclair, G., Sion, E., Kluwer, Dordrecht, p. 249 Google Scholar
Chayer, P., LeBlanc, F., Fontaine, G., et al. 1994, ApJ, 436, L161 CrossRefGoogle Scholar
Chayer, P., Fontaine, G., & Wesemael, F. 1995a, ApJS, 99, 189 Google Scholar
Chayer, P., Vennes, S., Pradhan, A.K., et al. 1995b, ApJ, 454, 429 CrossRefGoogle Scholar
Chayer, P., Kruk, J. W., Ake, T. B., Dupree, A. K., Malina, R. F., Siegmund, O. H. W., Sonneborn, G., & Ohl, R. G. 2000, ApJ, 538, L91 CrossRefGoogle Scholar
Dreizler, S. 1999, A&A, 352, 632 Google Scholar
Dreizler, S. 2002, in Stellar Atmosphere Modeling, ASP Conference Series, ed. Hubeny, I., Mihalas, D., & Werner, K., in press Google Scholar
Dreizler, S., & Wolff, B. 1999, A&A, 348, 189 Google Scholar
Greenstein, J. S., Truran, J. W., & Cameron, A. G. W. 1967, Nature, 213, 871 Google Scholar
Heber, U., Napiwotzki, R., & Reid, I. N. 1997, A&A, 323, 819 Google Scholar
Holberg, J. B., Barstow, M. A., Bruhweiler, F. C., Hubeny, I., & Green, E. M. 1999, ApJ, 517, 850 Google Scholar
Hui-Bon-Hoa, A., LeBlanc, F., Hauschildt, P. H., & Baron, E. 2002, A&A, 381, 197 Google Scholar
Jordan, S., Koester, D., Wulf-Mathies, C., & Brunner, H. 1987, A&A, 185, 253 Google Scholar
Jordan, S., Wolff, B., Koester, D., & Napiwotzki, R. 1994, A&A, 290, 834 Google Scholar
Kahn, S. M., Wesemael, F., Liebert, J., Raymond, J. C., Steiner, J. E., & Shipman, H. L. 1984, ApJ, 278, 255 Google Scholar
Kawaler, S. D., & Bradley, P. A. 1994, ApJ, 427, 415 Google Scholar
Koester, D., Dreizler, S., Weidemann, V., & Allard, N. F. 1998, A&A, 338, 612 Google Scholar
Lampton, M., Margon, B., Paresce, F., Stern, R., & Bowyer, S. 1976, ApJL, 203, L71 Google Scholar
Lanz, T., Barstow, M. A., Hubeny, I., & Holberg, J. B. 1996, ApJ, 473, 1089 Google Scholar
Margon, B., Malina, R., Bowyer, S., Cruddace, R., & Lampton, M. 1976, ApJ, 203, L25 Google Scholar
Mewe, R., Heise, J., Gronenschild, E. H. B. M., Brinkman, A. C., Schrijver, J., & den Boggende, A. J. F. 1975, ApJ, 202, L67 CrossRefGoogle Scholar
Michaud, G. 1970, ApJ, 160, 641 Google Scholar
Michaud, G., Vauclair, G., & Vauclair, S. 1983, ApJ, 267 256 Google Scholar
Morvan, E., Vauclair, G., & Vauclair, S. 1986, A&A, 163, 145 Google Scholar
Paerels, F. B. S. & Heise, J. 1989, ApJ, 339, 1000 Google Scholar
Petre, R., Shipman, H. L., & Canizares, C. R. 1986, ApJ, 304, 356 Google Scholar
Schatzman, E. 1949, Publ. Köbenhavns Obs. No. 149 Google Scholar
Schatzman, E. 1958, White Dwarfs, North Holland Publ. Comp., Amsterdam Google Scholar
Schuh, S. L., Dreizler, S., & Wolff, B. 2002, A&A, 382, 164 Google Scholar
Shipman, H. L. 1976, ApJ, 206, L67 Google Scholar
Sion, E. M., Bohlin, R. C., Tweedy, R. W., & Vauclair, G. P. 1992, ApJ, 391, L29 Google Scholar
Unglaub, K., & Bues, I. 1998, A&A 338, 75 Google Scholar
Unglaub, K., & Bues, I. 2000, A&A 359, 1042 Google Scholar
Unglaub, K., & Bues, I. 2001, A&A 374, 570 Google Scholar
Vauclair, G. 1987, in IAU Colloquium No. 95, The Second Conference on Faint Blue Stars, ed. Philip, A. G. D., Hayes, D. S., & Liebert, J. W., L. Davis Press, Schenectady, p. 341 Google Scholar
Vauclair, G. 1989, in White Dwarfs, ed. Wegner, G., Springer, Berlin, p. 176 Google Scholar
Vauclair, G., Vauclair, S., & Greenstein, J. L. 1979, A&A 80, 79 Google Scholar
Vennes, S., & Lanz, T. 2001, ApJ, 553, 399 Google Scholar
Vennes, S., Chayer, P., Fontaine, G., & Wesemael, F. 1989, ApJL, 336, L25 Google Scholar
Vennes, S., Chayer, P., Thorstensen, J.R., Bowyer, S., & Shipman, H.L. 1992, ApJ 392, L27 Google Scholar
Vennes, S., Chayer, P., Hurwitz, M., & Bowyer, S. 1996, ApJ 468, 898 Google Scholar
Vidal-Madjar, A., Allard, N. F., Koester, D., Lemoine, M., Ferlet, R., Bertin, P., Lallement, R., & Vauclair, G. 1994, A&A, 287, 175 Google Scholar
Werner, K., & Dreizler, S. 1994, A&A, 286, L31 Google Scholar
Werner, K., & Dreizler, S. 1999, in Computational Astrophysics, eds. Riffert, H. & Werner, K., Journal of Computational and Applied Mathematics, 109, 65 Google Scholar
Wolff, B., Jordan, S., & Koester, D. 1996, A&A, 307, 149 Google Scholar
Wolff, B., Koester, D., Dreizler, S., & Haas, S. 1998, A&A, 329, 1045 Google Scholar