Astronomy and Astrophysics Sulphur Abundances in Disk Stars: a Correlation with Silicon

We have performed new determinations of sulphur and silicon abundances for a sample of 26 disk stars based on high-resolution, high signal-to-noise spectra. The results indicate a solar [S/Fe] for [Fe/H] > −0.3, below which [S/Fe] increases to ∼0.25 dex at [Fe/H] = −1.0. We find that there is a good correlation between [S/H] and [Si/H], indicating the same nucleosynthetic origin of the two elements. It seems that the ratio of sulphur to silicon does not depend on metallicity for [Fe/H] > −1.0. The implications of these results on models for the nucleosyn-thesis of α-capture elements and the chemical evolution of the Galaxy are discussed. A&A manuscript no. (will be inserted by hand later) Your thesaurus codes are: missing; you have not inserted them