Deep SDSS optical spectroscopy of distant halo stars I. Atmospheric parameters and stellar metallicity distribution

C. Allende Prieto, E. Fernandez-Alvar, K. J. Schlesinger +14

We analyze a sample of tens of thousands of spectra of halo turnoff stars, obtained with the optical spectrographs of the Sloan Digital Sky Survey (SDSS), to characterize the stell…