We present the initial results from our search for high redshift , z \ga 6 , quasars using near infrared data from the UKIRT Infrared Deep Sky Survey ( UKIDSS ) Large Area Survey ( LAS ) .
Our analysis of 106 deg ^ { 2 } of sky from Data Release 1 ( DR1 ) has resulted in the discovery of ULAS J020332.38+001229.2 , a luminous ( J _ { AB } = 20.0 , J _ { Vega } = 19.1 , M _ { 1450 } = -26.2 ) quasar at z = 5.86 .
Following candidate selection from the combined IR and optical catalogue data and stacking of multiple epoch Sloan Digital Sky Survey ( SDSS ) data , we have obtained optical spectroscopy for the only two z \ga 6 quasar candidates .
The VLT FORS2 spectrum of ULAS J020332.38+001229.2 shows broad Ly \alpha + N V 1240 emission at \sim 8350 Å and an abrupt continuum break due to absorption by the Ly \alpha forest .
The quasar is not present in the SDSS DR5 catalogue and the continuum spectral index of \alpha =-1.4 ( F _ { \nu } \propto \nu ^ { \alpha } ) is redder than a composite of SDSS quasars at similar redshifts ( \alpha =-0.5 ) .
The discovery of one z \sim 6 quasar in \sim 100 deg ^ { 2 } in a complete sample within our selection criteria down to a median depth of Y _ { AB } = 20.4 ( 7 \sigma ) is consistent with existing SDSS results .
We describe our survey methodology , including the use of optical data from the SDSS and the highly effective procedures developed to isolate the very small surface density of high-probability quasar candidates .