The Discovery of a Five-Image Lensed Quasar at z = 3.34 using PanSTARRS1
  and Gaia
  We report the discovery, spectroscopic confirmation, and mass modelling of
the gravitationally lensed quasar system PS J0630-1201. The lens was discovered
by matching a photometric quasar catalogue compiled from Pan-STARRS and WISE
photometry to the Gaia DR1 catalogue, exploiting the high spatial resolution of
the latter (FWHM $\sim $0.1") to identify the three brightest components of the
lens. Follow-up spectroscopic observations with the WHT confirm the multiple
objects are quasars at redshift $z_{q}=3.34$. Further follow-up with Keck AO
high-resolution imaging reveals that the system is composed of two lensing
galaxies and the quasar is lensed into a $\sim$2.8" separation four-image cusp
configuration with a fifth image clearly visible, and a 1.0" arc due to the
lensed quasar host galaxy. The system is well-modelled with two singular
isothermal ellipsoids, reproducing the position of the fifth image. We discuss
future prospects for measuring time delays between the images and constraining
any offset between mass and light using the faintly detected Einstein arcs
associated with the quasar host galaxy.
