IUE observations of SI and C lines and comparison with non-LTE models

Abstract

view Abstract Citations (36) References (17) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS IUE observations of SI and C lines and comparison with non-LTE models. Kamp, L. W. Abstract Classical model atmosphere techniques are applied to analyze IUE spectra, and to determine abundances, effective temperatures and gravities. Measurements of the equivalent widths and other properties of the line profiles of 24 photospheric lines of Si II, Si III, Si IV, C II, C III and C IV are presented in the range of 1175-1725 A for seven B and two O stars. Observed line profiles are compared with theoretical profiles computed using non-LTE theory and models, and using line-blanketed model atmospheres. Agreement is reasonably good, although strong lines are calculated to be systematically stronger than those observed, while the reverse occurs for weak lines, and empirical profiles have smaller wings than theoretical profiles. It is concluded that the present theory of line formation when used with solar abundances, represents fairly well observed UV photospheric lines of silicon and carbon ions in the atmospheres of main sequence stars of types B5-O9. Publication: The Astrophysical Journal Supplement Series Pub Date: April 1982 DOI: 10.1086/190784 Bibcode: 1982ApJS...48..415K Keywords: Carbon; Early Stars; Line Spectra; Photosphere; Silicon; Stellar Atmospheres; Stellar Spectra; Ultraviolet Spectra; Absorption Spectra; Abundance; B Stars; Iue; O Stars; Spectral Line Width; Spectrum Analysis; Stellar Gravitation; Stellar Temperature; Astrophysics full text sources ADS | data products SIMBAD (9) MAST (1)