Photospheres of Hot Stars. IV - Spectral Type O4

view Abstract Citations (31) References (22) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Photospheres of Hot Stars. IV. Spectral Type O4 Bohannan, Bruce ; Voels, Stephen A. ; Hummer, David G. ; Abbott, David C. Abstract The basic stellar parameters of a supergiant (Zeta Pup) and two main-sequence stars, 9 Sgr and HD 46223, at spectral class O4 are determined using line profile analysis. The stellar parameters are determined by comparing high signal-to-noise hydrogen and helium line profiles with those from stellar atmosphere models which include the effect of radiation scattered back onto the photosphere from an overlying stellar wind, an effect referred to as wind blanketing. At spectral class O4, the inclusion of wind-blanketing in the model atmosphere reduces the effective temperature by an average of 10 percent. This shift in effective temperature is also reflected by shifts in several other stellar parameters relative to previous O4 spectral-type calibrations. It is also shown through the analysis of the two O4 V stars that scatter in spectral type calibrations is introduced by assuming that the observed line profile reflects the photospheric stellar parameters. Publication: The Astrophysical Journal Pub Date: December 1990 DOI: 10.1086/169526 Bibcode: 1990ApJ...365..729B Keywords: Early Stars; O Stars; Photosphere; Radiative Transfer; Stellar Atmospheres; Supergiant Stars; Abundance; Helium; Line Spectra; Signal To Noise Ratios; Stellar Luminosity; Stellar Mass; Stellar Spectra; Astrophysics; LINE PROFILES; RADIATIVE TRANSFER; STARS: ATMOSPHERES; STARS: EARLY-TYPE; STARS: SUPERGIANTS full text sources ADS | data products SIMBAD (7) Related Materials (3) Part 1: 1985ApJ...294..286A Part 2: 1986ApJ...308..728B Part 3: 1989ApJ...340.1073V