Aims: We analyze a sample of 3944 low-resolution (R ~ 2000) optical spectra from the Sloan Digital Sky Survey (SDSS), focusing on stars with effective temperatures 5800 ≤ Teff ≤ 6300 K, and distances from the Milky Way plane in excess of 5 kpc, and determine their abundances of Fe, Ca, and Mg. Methods: We followed the same methodology as in the

All studies of unresolved stellar populations rely on a proper characterization of the stellar initial mass function (IMF), i.e. the distribution of stellar masses at birth. Over the past few years, several avenues of research have suggested a systematic variation of the IMF in early-type galaxies, with a departure from the standard IMF in the most

Spectroscopic data of low-mass X-ray binaries (LMXB) can provide valuable information on supernova properties. In these systems the companion star is probably close enough to be polluted by some of the matter ejected during the supernova (SN) event of the progenitor of the compact object. We present high-resolution spectra, acquired with UES@WHT

We use integral field spectroscopy of 13 disk galaxies in the cluster AC114 at z ˜ 0.31 in an attempt to disentangle the physical processes responsible for the transformation of spiral galaxies in clusters. Our sample is selected to display a dominant young stellar population, as indicated by strong Hδ absorption lines in their integrated spectra

With the help of CARMENCITA, the CARMENES Cool dwarf Information and datA Archive, we investigate the multiplicity of M dwarfs in the solar neighnourhood observable from Calar Alto to prepare and characterize the final sample of stars of CARMENES. Our multiplicity study covers a wide range in projected physical separations, from 0.5 to 50 000 au

We present preliminary results of deep echelle spectrophotometry of a sample of HII regions along the disk of the Scd galaxy NGC 300 obtained with the Ultraviolet and Visual Echelle Spectrograph (UVES) at the Very Large Telescope (VLT) with the aim of detect and measure very faint oii\ and χ permitted lines. We focus this study on the C and O