Two stellar components in the halo of the Milky Way

@article{Carollo2007TwoSC,
  title={Two stellar components in the halo of the Milky Way},
  author={Daniela Carollo and Timothy C. Beers and Young Sun Lee and Masashi Chiba and John E. Norris and Ronald Wilhelm and T. S. Sivarani and Brian Elliott Marsteller and Jeffrey A. Munn and Coryn A. L. Bailer-Jones and Paola Re Fiorentin and Donald G. York},
  journal={Nature},
  year={2007},
  volume={450},
  pages={1020-1025}
}
The halo of the Milky Way provides unique elemental abundance and kinematic information on the first objects to form in the Universe, and this information can be used to tightly constrain models of galaxy formation and evolution. Although the halo was once considered a single component, evidence for its dichotomy has slowly emerged in recent years from inspection of small samples of halo objects. Here we show that the halo is indeed clearly divisible into two broadly overlapping structural… 

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