Elemental Abundances in Evolved Supergiants. I. NGC 330, a Young SMC Cluster

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Abstract
We report on the results of our analyses of high-quality spectroscopic observations of seven giants in NGC 330. The mean value of [Fe/H] for the cluster is -0.94 ± 0.02 (σ = 0.04). This is consistent with the results of Spite et al. and slightly less than those of the recent study of V. Hill. We see evidence of the products of CNO cycling. The average ratio of 12C/13C is near 8, which is about half of the value predicted by the models of Schaller et al., but we do not detect the predicted enhancement of 0.3–0.6 dex in the N abundance. We find no excess of O relative to Fe despite the stars' low metallicities. Our analysis of the heavy elements from Zr to Eu indicates that the ratio of r/s processes is greater in NGC 330 than in the Sun.