Quasar lenses and pairs in the VST-ATLAS and Gaia
  We report on discovery results from a quasar lens search in the ATLAS public
footprint, extending quasar lens searches to a regime without $u-$band or
fiber-spectroscopic information, using a combination of data mining techniques
on multi-band catalog magnitudes and image-cutout modelling. Spectroscopic
follow-up campaigns, conducted at the 2.6m Nordic Optical Telescope (La Palma)
and 3.6m New Technology Telescope (La Silla) in 2016, yielded seven pairs of
quasars exhibiting the same lines at the same redshift and monotonic
flux-ratios with wavelength (hereafter NIQs, Nearly Identical Quasar pairs).
The quasar redshifts range between $\approx1.2$ and $\approx 2.7;$ contaminants
are typically pairs of bright blue stars, quasar-star alignments along the line
of sight, and narrow-line galaxies at $0.3<z<0.7.$ Magellan data of A0140-1152
(01$^h$40$^m$03.0$^s$-11$^d$52$^m$19.0$^s$, $z_{s}=1.807$) confirm it as a lens
with deflector at $z_{l}=0.277$ and Einstein radius $\theta_{\rm
E}=(0.73\pm0.02)^\ase$. We show the use of spatial resolution from the Gaia
mission to select lenses and list additional systems from a WISE-Gaia-ATLAS
search, yielding three additional lenses
(02$^h$35$^m$27.4$^s$-24$^d$33$^m$13.2$^s$,
02$^h$59$^m$33.$^s$-23$^d$38$^m$01.8$^s$,
01$^h$46$^m$32.9$^s$-11$^d$33$^m$39.0$^s$). The overall sample consists of 11
lenses/NIQs, plus three lenses known before 2016, over the ATLAS-DR3 footprint
($\approx3500$~deg$^2$). Finally, we discuss future prospects for objective
classification of pair/NIQ/contaminant spectra.
