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Metal rich stars in omega Cen: preliminary FLAMES GTO results

E. Pancino
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Abstract

I present preliminary results for a sample of ~700 red giants in omega Cen, observed during the Ital-FLAMES Consortium GTO time in May 2003, for the Bologna Project on omega Cen. Preliminary Fe and Ca abundances confirm previous results: while the metal-poor and intermediate populations show a normal halo alpha-enhancement of [alpha/Fe]=$+0.3, the most metal-rich stars show a significantly lower [alpha/Fe]=+0.1. If the metal-rich stars have evolved within the cluster in a process of self-enrichment, the only way to lower their alpha-enhancement would be SNe type Ia intervention.

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E. Pancino. 2004-10-28. Metal rich stars in omega Cen: preliminary FLAMES GTO results. https://doi.org/10.1007/978-3-540-34136-9_39

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