3 papers
astro-ph2004
Iron abundances from high-resolution spectroscopy of the open clusters NGC 2506, NGC 6134, and IC 4651
E. Carretta, A. Bragaglia, R. G. Gratton +1
This is the first of a series of papers devoted to derive the metallicity of old open clusters in order to study the time evolution of the chemical abundance gradient in the Galact…
astro-ph2003
Abundances for metal-poor stars with accurate parallaxes II. alpha-elements in the halo
Raffaele Gratton, Eugenio Carretta, Silvano Desidera +3
Abundances for alpha-elements and Fe in about 150 field subdwarfs and early subgiants with accurate parallaxes and kinematic data are used to discuss the run of abundance ratios in…
astro-ph2003
Abundances for metal-poor stars with accurate parallaxes I. Basic data
Raffaele Gratton, Eugenio Carretta, Riccardo Claudi +2
We present element-to-element abundance ratios measured from high dispersion spectra for 150 field subdwarfs and early subgiants with accurate Hipparcos parallaxes (errors <20%). F…