Discovery of the first quadruple gravitationally lensed quasar candidate
  with Pan-STARRS
  We report the serendipitous discovery of the first gravitationally lensed
quasar candidate from Pan-STARRS. The grizy images reveal four point-like
images with magnitudes between 14.9 mag and 18.1 mag. The colors of the point
sources are similar, and they are more consistent with quasars than with stars
or galaxies. The lensing galaxy is detected in the izy bands, with an inferred
photometric redshift of ~0.6, lower than that of the point sources. We
successfully model the system with a singular isothermal ellipsoid with shear,
using the relative positions of the five objects as constraints. While the
brightness ranking of the point sources is consistent with that of the model,
we find discrepancies between the model-predicted and observed fluxes, likely
due to microlensing by stars and millilensing due to the dark matter
substructure. In order to fully confirm the gravitational lens nature of this
system and add it to the small but growing number of the powerful probes of
cosmology and astrophysics represented by quadruply lensed quasars, we require
further spectroscopy and high-resolution imaging.
