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non-lte, line-blanketed model atmospheres for late o- and early b-type starsThe use of non-LTE line-blanketed model atmospheres to analyze the spectra of hot stars is reported. The stars analyzed are members of clusters and associations, have spectral types in the range O9-B2 and luminosity classes in the range III-IV, have slow to moderate rotation, and are photometrically constant. Sampled line opacities of iron-group elements were incorporated in the radiative transfer solution; solar abundances were assumed. Good to excellent agreement is obtained between the computed profiles and essentially all the line profiles used to fix the model, and reliable stellar parameters are derived. The synthetic M II 5581 equivalent widths agree well with the observed ones at the low end of the temperature range studied, but, above 25,000 K, the synthetic line is generally stronger than the observed line. The behavior of the observed equivalent widths of N II, N III, C II and C III lines as a function of Teff is studied. Most of the lines show much scatter, with no consistent trend that could indicate abundance differences from star to star.
Document ID
19920038082
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Grigsby, James A.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Morrison, Nancy D.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Anderson, Lawrence S.
(Toledo, University OH, United States)
Date Acquired
August 15, 2013
Publication Date
January 1, 1992
Publication Information
Publication: Astrophysical Journal Supplement Series
Volume: 78
ISSN: 0067-0049
Subject Category
ASTROPHYSICS
Funding Number(s)
CONTRACT_GRANT: NAG5-970
CONTRACT_GRANT: NAG5-979
Distribution Limits
Public
Copyright
Other