Deep SDSS optical spectroscopy of distant halo stars II. Iron, calcium, and magnesium abundances

@article{FernandezAlvar2015DeepSO,
  title={Deep SDSS optical spectroscopy of distant halo stars II. Iron, calcium, and magnesium abundances},
  author={Emma Fern'andez-Alvar and Carlos Allende Prieto and Katharine J. Schlesinger and Timothy C. Beers and Annie C. Robin and Donald P. Schneider and Y. S. Lee and Dmitry Bizyaev and Garrett L. Ebelke and Elena Malanushenko and Viktor Malanushenko and Daniel J. Oravetz and K. Pan and Audrey Simmons},
  journal={arXiv: Solar and Stellar Astrophysics},
  year={2015}
}
We analyze a sample of 3,944 low-resolution (R ~ 2000) optical spectra from the Sloan Digital Sky Survey (SDSS), focusing on stars with effective temperatures 5800 < Teff < 6300 K, and distances from the Milky Way plane in excess of 5 kpc, and determine their abundances of Fe, Ca, and Mg. We followed the same methodology as in the previous paper in this series, deriving atmospheric parameters by chi2 minimization, but this time we obtained the abundances of individual elements by fitting their… 

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