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Status of Wolf-Rayet models

Published online by Cambridge University Press:  07 August 2017

D. J. Hillier*
Affiliation:
Department of Physics and Astronomy, University of Pittsburgh, 3941 O'Hara Street, Pittsburgh, PA 15260, U.S.A.

Abstract

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In the last decade there has been a tremendous advance in our understanding of the atmospheres and stellar winds of Wolf-Rayet (WR) stars. This has arisen through improved observations, and through the application of extensive radiative transfer codes which has allowed us to model some of the complex processes occurring in WR envelopes. Present models are able to simultaneously treat detailed atomic models for H, He, C, N, O and Si. In the near future we will be able to treat Fe, and to more accurately treat the formidable problem of non-LTE line-blanketing. In this review we address current limitations in modeling the extended atmospheres of WR atmospheres. These limitations fall into two classes — those reflecting our inability to accurately compute the “Standard Model”, and those referring to assumptions in the “Standard Model” that need to be relaxed. Under the first category we include inaccuracies in the atomic data, the neglect of line-blanketing in the model calculations, and the inability of the present generation of models to compute the velocity law. Under the second category we include the assumption of spherical geometry, the assumption of homogeneity, the neglect of rotation, and the influence of X-rays arising from shocks in the stellar wind.

Type
Session II - Model atmospheres for single Wolf-Rayet stars
Copyright
Copyright © Kluwer 1995 

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