The Metal-poor Metallicity Distribution of the Ancient Milky Way

  title={The Metal-poor Metallicity Distribution of the Ancient Milky Way},
  author={Anirudh Chiti and Mohammad K. Mardini and Anna Frebel and Tatsuya W. Daniel},
  journal={The Astrophysical Journal Letters},
We present a low-metallicity map of the Milky Way consisting of ∼110,000 metal-poor giants with −3.5 < [Fe/H] < −0.75, based on public photometry from the second data release of the SkyMapper survey. These stars extend out to ∼7 kpc from the solar neighborhood and cover the main Galactic stellar populations, including the thick disk and the inner halo. Notably, this map can reliably differentiate metallicities down to [Fe/H] ∼ −3.0, and thus provides an unprecedented view into the ancient… 
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