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Improved Non-LTE Model Atmospheres for Subluminous O-Stars

Published online by Cambridge University Press:  19 July 2016

U. Heber
Affiliation:
Institut für Theoretische Physik und Sternwarte, Olshausenstr. 40, D2300 Kiel 1, Federal Republic of Germany
K. Hunger
Affiliation:
Institut für Theoretische Physik und Sternwarte, Olshausenstr. 40, D2300 Kiel 1, Federal Republic of Germany
T. Rauch
Affiliation:
Institut für Theoretische Physik und Sternwarte, Olshausenstr. 40, D2300 Kiel 1, Federal Republic of Germany
K. Werner
Affiliation:
Institut für Theoretische Physik und Sternwarte, Olshausenstr. 40, D2300 Kiel 1, Federal Republic of Germany

Abstract

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Improved non-LTE model atmospheres designed for the analysis of very hot subluminous O stars are presented. The calculations are based on the new method of the accelerated lambda iteration (ALI) which proves capable of treating up to 100 levels of various ions. Presented here are improved calculations for (i) pure hydrogen model atmospheres including Stark broadening, (ii) for hydrogen- and helium-composed model atmospheres and (iii) first preliminary models which include in addition a detailed carbon model atom. These models remove an apparent mismatch of Balmer line profiles noted previously and fit high S/N, high-resolution hydrogen and helium spectra obtained with the ESO-Cassegrain echelle spectrograph very well.

Type
III. Stars
Copyright
Copyright © Kluwer 1988 

References

Anderson, L.S: 1985, in “Progress in Stellar Line Formation Theory”, Beckman, J. F., Crivellari, L. (eds.), Reidel, p.225 Google Scholar
Auer, L.H., Mihalas, D.: 1969, Astrophys. J. 158, 641 Google Scholar
Hamann, W.-R., Gruschinske, J., Kudritzki, R.P., Simon, K.P.: 1981, Astron. Astrophys. 104, 249 Google Scholar
Heber, U.: 1986, Astron. Astrophys. 155, 33 Google Scholar
Heber, U., Kudritzki, R.P.: 1986, Astron. Astrophys. 169, 244 Google Scholar
Herrero, A.: 1987, Astron. Astrophys. 171, 189 Google Scholar
Kudritzki, R.P., Simon, K.P.: 1978, Astron. Astrophys. 70, 653 Google Scholar
Kudritzki, R.P., Simon, K.P., Lynas–Gray, A.E., Hill, P.W.: 1982, Astron. Astrophys. 106, 254 Google Scholar
Rauch, T.: 1987, , KielGoogle Scholar
Scharmer, G.: 1981, Astrophys. J. 249, 720 Google Scholar
Starrfield, S.G., Cox, A.N., Kidman, R.B., Pesnell, W.D.: 1984, Astrophys. J. 281, 800 CrossRefGoogle Scholar
Werner, K.: 1986, Astron. Astrophys. 161, 127 Google Scholar
Werner, K.: 1987a, in “Numerical Methods in Radiative Transfer”, Kalkofen, W. (ed.), Cambridge University Press, in press Google Scholar
Werner, K.: 1987b, , KielGoogle Scholar
Werner, K., Husfeld, D.: 1985, Astron. Astrophys. 148, 417 Google Scholar