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| - Sulphur abundances in Terzan 7
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| - We present here the first measurements of sulphur abundances in extragalactic stars. We make use of high resolution spectra, obtained with UVES at the ESO 8.2 m Kueyen telescope, of three giants of the Globular Cluster Terzan 7, which belongs to the Sagittarius dwarf galaxy. We measure the sulphur abundances using the lines of $\ion{S}{i}$ multiplet 1. The S/Fe ratios for all three stars are nearly solar, thus considerably lower than what is found in Galactic stars of comparable iron content $({\rm [Fe/H]} \sim -0.50$). This finding is in keeping with the abundances of other α-chain elements in this cluster and in Sagittarius and other dSphs in general. These low α-chain elements to iron ratios suggest that Sagittarius and its Globular Clusters have experienced a low or bursting star-formation rate. Our sulphur abundances imply $\langle \log ({\rm S/O})\rangle = -1.61$ which is comparable to what is found in many $\ion{H}{ii}$ regions of similar oxygen content, and is slightly lower than the solar value ( $\log ({\rm S/O})_{odot} = -1.51$). These are also the first measurements of sulphur abundances in a Globular Cluster, thus a direct comparison of Terzan 7 and Galactic Globular Clusters is not possible yet. However our analysis suggests that the lines of $\ion{S}{i}$ multiplet 1 should be measurable for other Globular Clusters at least down to a metallicity ~-1.5.
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