Photometry of O-type stars, interpreted with reference to model atmospheres

Abstract

view Abstract Citations (38) References (19) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Photometry of O-type stars, interpreted with reference to model atmospheres. Morrison, N. D. Abstract UVBY and H-beta photometry is conducted for 101 O-type stars with the aim of comparing effective temperatures derived from this photometry with those based on spectral lines to check on the self-consistency of non-LTE models for these stars. Also, Stroemgren-system colors for O-type stars are compared with colors calculated from non-LTE model atmospheres as well as from models with extended geometry. It is found that the effective temperatures derived from the photometry agree with those derived from a ratio of spectral-line intensities and that the calculated colors are consistent with calculated line-strengths for the non-LTE plane-parallel models. The c1 Stroemgren index is shown to be consistently more negative for certain O-type stars than it is for main-sequence stars by an amount consistent with the predictions of the extended-geometry models. For stars earlier than type O6, this index is shown to be consistently more positive than the plane-parallel models predict. Possible causes of this effect are considered. Publication: The Astrophysical Journal Pub Date: August 1975 DOI: 10.1086/153767 Bibcode: 1975ApJ...200..113M Keywords: Astronomical Models; Atmospheric Models; Early Stars; O Stars; Stellar Atmospheres; Stellar Spectrophotometry; Line Spectra; Stellar Evolution; Stellar Temperature; Thermodynamic Equilibrium; Ubv Spectra; Astronomy full text sources ADS | data products SIMBAD (102) GCPD (1)