NGC 5128 globular cluster candidates out to 150 kpc: a comprehensive
  catalog from Gaia and ground based data
  We present a new catalog of 40502 globular cluster (GC) candidates in NGC
5128 out to a projected radius of $\sim$150 kpc, based on data from the
Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS), Gaia Data Release
2, and the NOAO Source Catalog. Ranking these candidates based on the
likelihood that they are true GCs, we find that approximately 1900 belong to
our top two ranking categories and should be the highest priority for
spectroscopic follow-up for confirmation. Taking into account our new data and
a vetting of previous GC catalogs, we estimate a total GC population of $1450
\pm 160$ GCs. We show that a substantial number of sources previously argued to
be low-velocity GCs are instead foreground stars, reducing the inferred GC
velocity dispersion. This work showcases the power of Gaia to identify slightly
extended sources at the $\sim 4$ Mpc distance of NGC 5128, enabling accurate
identification of GCs throughout the entire extended halo, not just the inner
regions that have been the focus of most previous work.
