Hostname: page-component-7bb8b95d7b-dvmhs Total loading time: 0 Render date: 2024-09-20T23:25:51.418Z Has data issue: false hasContentIssue false

The Importance of Radiative Transfer in Stellar Pulsation Models

Published online by Cambridge University Press:  12 April 2016

C. G. Davis*
Affiliation:
Los Alamos National Laboratory, Physics Division, P. O. Box 1663, Los Alamos, NM 87545, USA

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.

With the advent of new astrophysical opacities it seems appropriate to discuss the need for a full radiative transfer (RT) theory instead of the usual equilibrium diffusion theory used in most nonlinear pulsation codes. Early studies on the importance of RT in the calculation of light curves for Cepheid models showed little effect over diffusion theory. The new opacities though may help to explain the “bump” mass discrepancy problem. For RR Lyrae models the use of RT theory causes some effects both in the color differences (U-B) as well as in the light curves. New opacities help to explain the period ratios for double mode RR Lyrae and beat Cepheids. A new area of research is in the modeling of stars with high luminosity to mass ratios that show tendencies for doubling and transitions to chaos, such as W Virginis and RV Tauri stars. For these stars it has been shown that RT is necessary in calculating their light curves and that the understanding of the shock dynamics depends on the transfer of lines in the pulsating RT dependent atmospheres (Fokin 1991).

Type
III. Models
Copyright
Copyright © Kluwer 1993

References

Cullen, D. and Pomraning, G.: 1980, JQSRT No.24, 29.Google Scholar
Daeppen, W.: 1991, Present Status of the Opacity Project, presented at IAU commission 35 meeting, Buenos Aires, July 23-Aug. 1.Google Scholar
Davis, C.G.: 1972, Astrophysical Journal 172, 419.CrossRefGoogle Scholar
Davis, C.G.: 1976, in The Proceedings of IAU Colloquium No.29, ed. Fitch, W.S. (Publishing House of the Hungarian Academy of Sciences, Budapest, Hungary).Google Scholar
Fokin, A.B.: 1991, Monthly Notices of the RAS 250, 258.Google Scholar
Freeman, B.: 1965, General Atomic Report GAMD 6446.Google Scholar
Iglesias, C.A., Rogers, F.J., and Wilson, B.G.: 1987, Astrophysical Journal 322, L45.Google Scholar
Ishida, T. and Takeuti, M.: 1992, Publications of the ASJ, to be published.Google Scholar
Simon, N. and Aikawa, T.: 1986, Astrophysical Journal 304, 249.Google Scholar