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arXiv · 0808.0018

Ca II Triplet Spectroscopy of Small Magellanic Cloud Red Giants. I. Abundances and Velocities for a Sample of Clusters

M. C. Parisi·A. J. Grocholski·D. Geisler·A. Sarajedini·J. J. Claria
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Abstract

We have obtained near-infrared spectra covering the Ca II triplet lines for a number of stars associated with 16 SMC clusters using the VLT + FORS2. These data compose the largest available sample of SMC clusters with spectroscopically derived abundances and velocities. Our clusters span a wide range of ages and provide good areal coverage of the galaxy. Cluster members are selected using a combination of their positions relative to the cluster center as well as their abundances and radial velocities. We determine mean cluster velocities to typically 2.7 km/s and metallicities to 0.05 dex (random errors), from an average of 6.4 members per cluster. (continued in paper)

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M. C. Parisi, A. J. Grocholski, D. Geisler, A. Sarajedini, J. J. Claria. 2009-05-06. Ca II Triplet Spectroscopy of Small Magellanic Cloud Red Giants. I. Abundances and Velocities for a Sample of Clusters. https://doi.org/10.1088/0004-6256%2F138%2F2%2F517

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