Title: The Search for High-Redshift Quasars with UKIDSS 
Author(s): Mitesh Patel, Steve Warren (Imperial College London), 
Daniel Mortlock (Imperial College London),  Paul Hewett (Cambridge), 
Bram Venemans (ESO)
Abstract: The UKIRT Infra-red Deep Sky Survey (UKIDSS) is the next generation
infra-red deep sky survey. The Large Area Survey (LAS), within UKIDSS, aims to
observe 4000 deg^2 in Y, J, H and K, and provides near-ir counterparts
to SDSS, which are 3 magnitudes deeper than 2MASS.

We present ULAS J1319+0905, the first z>6 quasar discovered in the
UKIRT Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS).
Optical observations of the object with GMOS on Gemini-South were used
to confirm its nature, revealing strong absorption blueward of Lyman
alpha at a redshift of z ~= 6.1. An accurate redshift estimate of z =
6.127 +/- 0.004 was determined by observing the MgII emission line in
the near-IR with NIRI on Gemini-North.  We fit a power-law continuum
to the spectrum of ULAS J1319+0905, which reveals that it has similar
Lyman alpha absorption properties to other z ~= 6 quasars identified
in optical surveys.

This suggests that subsequent high-redshift quasars discovered in
near-IR sruveys like UKIDSS will be accurate probes of cosmological
reionization to a redshift of 7 and beyond.