SIMBAD references

We have obtained high-resolution high signal-to-noise ratio spectra of the S I near-infrared doublet at 8694 Å in eight metal-poor stars with metallicities in the range -0.6≤[Fe/H]≤-3.0. Elemental sulphur abundances were derived for six targets, and upper limits were set for two of the most metal-poor stars in the sample. The sulphur doublet at 8694.62 Å has been detected in three stars (HD 19445, HD 2665, and HD 2796) with [Fe/H]≤-1.9. Our observations, combined with those available in the literature, indicate a monotonic increase of the [S/Fe] ratio as [Fe/H] decreases, reaching values of [S/Fe]∼0.7-0.8 below [Fe/H]=-2. We discuss plausible scenarios for the interpretation of these results.