view Abstract Citations (124) References (76) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Atmospheres of Tau Scorpii (B0 v) and Lambda Leporis (B0.5 W) Hardorp, Johannes ; Scholz, M. Abstract New observations of the continuous and line spectra of r Sco and X Lep are reported. These spectra are studied by using model-atmosphere techniques in the LTE approach. Effective temperatures can be safely determined from ionization equilibria and Balmer jumps; surface gravities depend largely on the choice of hydrogen-broadening theories. For r Sco, Pfennig's theory and the mass-luminosity relation both point to a value for log g of about 4. The deep cores of H I and strong He I lines are not satisfactorlly predicted, probably because the models fall in the uppermost layers. The question of micro- turbulence is critically examined. Analyses of abundance are carried out with models = 32000 K, log g = 4.1, = 4.5 km -i for r Sco and Teff = 30900 K, Jog g = 4.05, = 4.5 km 1 for X Lep; Mihalas's unblanketed models are used. Most elements have solar abundances, neon is overabundant, and thecosmic iron abundance should be rediscussed. The wings of diffuse He I lines can be satisfactorily predicted with the abundance deduced from weak lines, if recent broadening theories are applied. The ratio of helium to hydrogen is about 0.10 by number, and its dependence on the choice of model is shown to be small. Publication: The Astrophysical Journal Supplement Series Pub Date: January 1970 DOI: 10.1086/190205 Bibcode: 1970ApJS...19..193H full text sources ADS | data products SIMBAD (7)