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arXiv · astro-ph/0611509

A Sr-Rich Star on the Main Sequence of Omega Centauri

Laura M. Stanford·G. S. Da Costa·John E. Norris·Russell D. Cannon
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Abstract

Abundance ratios relative to iron for carbon, nitrogen, strontium and barium are presented for a metal-rich main sequence star ([Fe/H]=--0.74) in the globular cluster omega Centauri. This star, designated 2015448, shows depleted carbon and solar nitrogen, but more interestingly, shows an enhanced abundance ratio of strontium [Sr/Fe] ~ 1.6 dex, while the barium abundance ratio is [Ba/Fe]<0.6 dex. At this metallicity one usually sees strontium and barium abundance ratios that are roughly equal. Possible formation scenarios of this peculiar object are considered.

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Laura M. Stanford, G. S. Da Costa, John E. Norris, Russell D. Cannon. 2006-11-16. A Sr-Rich Star on the Main Sequence of Omega Centauri. https://doi.org/10.1086/510530

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