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Model atmospheres, predicted spectra, and colorsTheoretical models of stellar atmospheres and the process of forming a spectrum are reviewed with particular reference to the spectra of B stars. In the case of classical models the stellar atmosphere is though to consist of plane parallel layers of gas in which radiative and hydrostatic equilibrium exists. No radiative energy is lost or gained in the model atmosphere, but the detailed shape of the spectrum is changed as a result of the interactions with the ionized gas. Predicted line spectra using statistical equilibrium local thermodynamic equilibrium (LTE), and non-LTE physics are compared and the determination of abundances is discussed. The limitations of classical modeling are examined. Models developed to demonstrate what motions in the upper atmosphere will do to the spectrum and to explore the effects of using geometries different from plane parallel layer are reviewed. In particular the problem of radiative transfer is addressed.
Document ID
19820017157
Acquisition Source
Legacy CDMS
Document Type
Other - Other
Date Acquired
August 10, 2013
Publication Date
January 1, 1982
Publication Information
Publication: B stars With and Without Emission Lines, Parts 1 and 2
Subject Category
Astrophysics
Accession Number
82N25033
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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