Study of abundance analysis of stars in the spectral range B5 through G2 Semiannual progress report, 1 Jun. - 30 Nov. 1969

Research in helium abundance, blue stragglers, and stars in contraction phas

Model atmospheres for RR Lyrae stars

Model atmospheres for RR Lyrae star

On the variation of the microturbulence parameter with chemical composition

Stellar model atmosphere abundance analysis to correlate microturbulent velocity parameters with iron to hydrogen ratio for G dwarf

Study of abundance analysis of stars in the spectral range B5 through G2 Final report

Photometric and spectroscopic study of blue stragglers, and evolution of stars in cluster

An analysis of the peculiar A star HD 204411

Spectrum analysis of cool Ap star HD 20441

Surface-gravity determinations for main-sequence B stars

Astronomical models for computing surface gravity of B stars from hydrogen line equivalent width

Analysis of F and G Subdwarfs. I. The Location of Subdwarfs in the Theoretical H-R Diagram

Spectrum scans and model stellar atmospheres have been used to locate in the (L/L_⊙, T_(eff)) plane F and G subdwarfs having known parallax A comparison is made between their position on the H-R diagram and the evolutionary tracks for Population II models of low- and high-helium content recently computed by Faulkner and Iben. The lower helium-content models are found to give somewhat more plausible ages than the high-helium models. Nevertheless, for both the low- and high-helium-content models, we find several subdwarfs with ages apparently greater than 10 X 10^9 years