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arXiv · 1008.4372

Detailed abundances of Red Giants in the Globular Cluster NGC~1851: C+N+O and the Origin of Multiple Populations

Sandro Villanova·Douglas Geisler·Giampaolo Piotto
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Abstract

We present chemical abundance analysis of a sample of 15 red giant branch (RGB) stars of the Globular Cluster NGC~1851 distributed along the two RGBs of the (v, v-y) CMD. We determined abundances for C+N+O, Na, $α$, iron-peak, and s-elements. We found that the two RGB populations significantly differ in their light (N,O,Na) and s-element content. On the other hand, they do not show any significant difference in their $α$ and iron-peak element content. More importantly, the two RGB populations do not show any significant difference in their total C+N+O content. Our results do not support previous hypotheses suggesting that the origin of the two RGBs and the two subgiant branches of the cluster is related to a different content of either $α$ (including Ca) or iron-peak elements, or C+N+O abundance, due to a second generation polluted by SNeII.

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Sandro Villanova, Douglas Geisler, Giampaolo Piotto. 2010-08-25. Detailed abundances of Red Giants in the Globular Cluster NGC~1851: C+N+O and the Origin of Multiple Populations. https://doi.org/10.1088/2041-8205%2F722%2F1%2Fl18

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