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arXiv · 1303.4168

CN Anomalies in the Halo System and the Origin of Globular Clusters in the Milky Way

Daniela Carollo·Sarah Martell·Timothy Beers·Ken Freeman
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Abstract

We explore the kinematics and orbital properties of a sample of red giants in the halo system of the Milky Way that are thought to have formed in globular clusters, based on their anomalously strong UV/blue CN bands. The orbital parameters of the CN-strong halo stars are compared to those of the inner- and outer-halo populations as described by Carollo et al., and to the orbital parameters of globular clusters with well-studied Galactic orbits. The CN-strong field stars and the globular clusters both exhibit kinematics and orbital properties similar to the inner-halo population, indicating that stripped or destroyed globular clusters could be a significant source of inner-halo field stars, and suggesting that both the CN-strong stars and the majority of globular clusters are primarily associated with this population.

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Daniela Carollo, Sarah Martell, Timothy Beers, Ken Freeman. 2013-03-18. CN Anomalies in the Halo System and the Origin of Globular Clusters in the Milky Way. https://doi.org/10.1088/0004-637x/769/2/87

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