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Present-day cosmic abundances - A comprehensive study of nearby early B-type stars and implications for stellar and Galactic evolution and interstellar dust models
Aims. A carefully selected sample of early B-type stars in OB associations and the field within the solar neighbourhood is studi ed comprehensively. Present-day abundances for the astrophysically
A Cosmic Abundance Standard: Chemical Homogeneity of the Solar Neighborhood and the ISM Dust-Phase Composition*
A representative sample of unevolved early B-type stars in nearby OB associations and the field is analyzed to unprecedented precision using NLTE techniques. The resulting chemical composition is
The First DIRECT Distance Determination to a Detached Eclipsing Binary in M33
We present the first direct distance determination to a detached eclipsing binary in M33, which was found by the DIRECT Project. Located in the OB 66 association at coordinates (alpha,
First stellar abundances in NGC 6822 from VLT-UVES and Keck-Hires spectroscopy
We have obtained the first high-resolution spectra of individual stars in the dwarf irregular galaxy NGC 6822. The spectra of the two A-type supergiants were obtained at the Very Large Telescope and
Helium enhanced stars and multiple populations along the horizontal branch of NGC 2808: direct spectroscopic measurements
We present an abundance analysis of 96 horizontal branch (HB) stars in NGC 2808, a globular cluster exhibiting a complex multiple stellar population p attern. These stars are distributed in different
A non-LTE study of neutral and singly-ionized calcium in late-type stars
Aims. Non-local thermodynamical equilibrium (NLTE) line formation for neutral and singly-ionized calcium is considered through a range of spectral types when the Ca abundance varies from the solar
Pristine CNO abundances from Magellanic Cloud B stars - I. The LMC cluster NGC 2004 with UVES
We present chemical abundances for four main sequence B stars in the young cluster NGC 2004 in the Large Magellanic Cloud (LMC). Apart from H II regions, unevolved OB-type stars are currently the
Quantitative spectroscopy of ba-type supergiants
Luminous BA-type supergiants have enormous potential for modern astrophysics. They allow topics ranging from non-LTE physics and the evolution of massive stars to the chemical evolution of galaxies
The Araucaria Project: The Local Group Galaxy WLM—Distance and Metallicity from Quantitative Spectroscopy of Blue Supergiants*
The quantitative analysis of low-resolution spectra of A and B supergiants is used to determine a distance modulus of 24.99 ± 0.10 mag (995 ± 46 kpc) to the Local Group galaxy WLM. The analysis
Analysis of Four A-F Supergiants in M31 from Keck HIRES Spectroscopy*
The first stellar abundances in M31 are presented, based on Keck I HIRES spectroscopy and model atmospheres analyses of three A-F supergiants, 41-2368, 41-3712, and A-207. We also present the