Journal: The Astrophysical Journal

  • Publication
    Chemical Cartography with APOGEE: Metallicity Distribution Functions and the Chemical Structure of the Milky Way Disk
    Using a sample of 69,919 red giants from the SDSS-III/APOGEE Data Release 12, we measure the distribution of stars in the [α/Fe] versus [Fe/H] plane and the...
  • Publication
    Chemical Cartography with APOGEE: Multi-element Abundance Ratios
    We map the trends of elemental abundance ratios across the Galactic disk, spanning R=3{--}15 {kpc} and midplane distance | Z| =0{--}2 {kpc}, for 15 elements in...
  • Publication
    Chemical Cartography with APOGEE: Two-process Parameters and Residual Abundances for 288,789 Stars from Data Release 17
    Stellar abundance measurements are subject to systematic errors that induce extra scatter and artificial correlations in elemental abundance patterns. We derive...
  • Publication
    Chemical Clues on the Formation of Planetary Systems: C/O Versus Mg/Si for HARPS GTO Sample
    Theoretical studies suggest that C/O and Mg/Si are the most important elemental ratios in determining the mineralogy of terrestrial planets. The C/O ratio...
  • Publication
    Chemical Composition of Two Bright, Extremely Metal-poor Stars from the SDSS MARVELS Pre-survey
    SDSS J082625.70+612515.10 (V = 11.4 [Fe/H] = ‑3.1) and SDSS J134144.60+474128.90 (V = 12.4 [Fe/H] = ‑3.2) were observed with the SDSS 2.5m telescope as part of...
  • Publication
    Chemical Compositions of Field and Globular Cluster RR Lyrae Stars. I. NGC 3201
    We present a detailed spectroscopic analysis of horizontal branch stars in the globular cluster NGC 3201. We collected optical (4580–5330 Å), high-resolution (...
  • Publication
    Chemical Compositions of Field and Globular Cluster RR Lyrae Stars. II. ω Centauri
    We present a detailed spectroscopic analysis of RR Lyrae (RRL) variables in the globular cluster NGC 5139 (ω Cen). We collected optical (4580–5330 Å), high...
  • Publication
    Chemical Evolution in the Milky Way: Rotation-based Ages for APOGEE-Kepler Cool Dwarf Stars
    We use models of stellar angular momentum evolution to determine ages for ∼500 stars in the APOGEE-Kepler Cool Dwarfs sample. We focus on lower-main-sequence...
  • Publication
    Chemical Tagging in the SDSS-III/APOGEE Survey: New Identifications of Halo Stars with Globular Cluster Origins
    We present new identifications of five red giant stars in the Galactic halo with chemical abundance patterns that indicate they originally formed in globular...