Chemo-Dynamical Clustering applied to APOGEE data: Re-Discovering
  Globular Clusters
  We have developed a novel technique based on a clustering algorithm which
searches for kinematically- and chemically-clustered stars in the APOGEE DR12
Cannon data. As compared to classical chemical tagging, the kinematic
information included in our methodology allows us to identify stars that are
members of known globular clusters with greater confidence. We apply our
algorithm to the entire APOGEE catalog of 150,615 stars whose chemical
abundances are derived by the Cannon. Our methodology found anti-correlations
between the elements Al and Mg, Na and O, and C and N previously identified in
the optical spectra in globular clusters, even though we omit these elements in
our algorithm. Our algorithm identifies globular clusters without a priori
knowledge of their locations in the sky. Thus, not only does this technique
promise to discover new globular clusters, but it also allows us to identify
candidate streams of kinematically- and chemically-clustered stars in the Milky
Way.
