ar X iv : a st ro - p h / 06 11 50 9 v 1 1 6 N ov 2 00 6 A Sr - Rich Star on the Main Sequence of Omega Centauri
نویسنده
چکیده
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 ω 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. Subject headings: globular clusters: general — globular clusters: individual (ω Centauri)
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