Bengt Gustafsson

TL;DR: In this article, an extensive grid of spherically-symmetric models (supplemented with plane-parallel ones for the highest surface gravities), built on up-to-date atomic and molecular data, is presented.

TL;DR: The Gaia-ESO Public Spectroscopic Survey has begun and will obtain high quality spectroscopy of some 100000 Milky Way stars, in the field and in open clusters, down to magnitude 19, systematically.

TL;DR: This work reports the discovery of a low-mass star with an iron abundance as low as 1/200,000 of the solar value, which suggests that population III stars could still exist and that the first generation of stars also contained long-livedLow-mass objects.

TL;DR: In this article, the chemical compositions of 30 Galactic carbon stars are determined from high-resolution infrared (1.5-2.5 ¡im) spectra and new model atmospheres.

TL;DR: Spectroscopic observations of stars in the metal-poor globular cluster NGC 6397 reveal trends of atmospheric abundance with evolutionary stage for various elements that are reproduced by stellar-evolution models with diffusion and turbulent mixing and conclude that diffusion is predominantly responsible for the low apparent stellar lithium abundance in the atmospheres of old stars.