Segue 1: An Unevolved Fossil Galaxy from the Early Universe

@article{Frebel2014Segue1A,
  title={Segue 1: An Unevolved Fossil Galaxy from the Early Universe},
  author={Anna Frebel and Joshua D. Simon and Evan N. Kirby},
  journal={The Astrophysical Journal},
  year={2014},
  volume={786},
  pages={74}
}
We present Magellan/MIKE and Keck/HIRES high-resolution spectra of six red giant stars in the dwarf galaxy Segue?1. Including one additional Segue?1 star observed by Norris et?al., high-resolution spectra have now been obtained for every red giant in Segue?1. Remarkably, three of these seven stars have metallicities below [Fe/H] = ?3.5, suggesting that Segue?1 is the least chemically evolved galaxy known. We confirm previous medium-resolution analyses demonstrating that Segue?1 stars span a… 
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