A Search for Gravitationally Lensed Quasars and Quasar Pairs in Pan-STARRS1: Spectroscopy and Sources of Shear in the Diamond 2M1134$-$2103

Understand

We present results of a systematic search for gravitationally lensed quasars in Pan-STARRS1.

• Our final sample of candidates comprises of 91 systems, not including 25 rediscovered lensed quasars and quasar pairs.
• In the absence of spectroscopy to verify the lensing nature of the candidates, the main sources of contaminants are likely to be quasar pairs, which we consider to be a byproduct of our work, and a smaller number of quasar$+$star associations.
• Amongst the independently discovered quads is 2M1134$-$2103, for which we obtained spectroscopy for the first time, finding a redshift of 2.77 for the quasar.