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We present results of the first systematic search for submillimetre continuum emission from z=2, radio-quiet, optically-luminous quasars, using the SCUBA/JCMT. We have observed a homogeneous sample of 57 quasars in the redshift range 1.5<z<3.0- the epoch during which the comoving density of luminous AGN peaks- to make a systematic comparison with an equivalent sample at high (z>4) redshift. The target sensitivity of the survey (3sigma=10mJy at 850um) was chosen to enable efficient identification of bright submm sources, suitable for detailed follow-up. 9 targets are detected, with fluxes in the range 7-17mJy. Although there is a suggestion of variation of submm detectability between z=2 and z=4, this is consistent with the K-correction of a characteristic far-infrared spectrum. Additionally, the weighted mean fluxes of non-detections at z=2 and z>4 are comparable.
We present the first data release (DR1) from our UV-bright Quasar Survey (UVQS) for new $z sim 1$ active galactic nuclei (AGN) across the sky. Using simple GALEX UV and WISE near-IR color selection criteria, we generated a list of 1450 primary candid
We have used the VLA FIRST survey and the APM catalog of the POSS-I plates as the basis for constructing a new radio-selected sample of optically bright quasars. This is the first radio-selected sample that is competitive in size with current optical
We present the results of the spectroscopic follow up of the QUBRICS survey. The selection method is based on a machine learning approach applied to photometric catalogs, covering an area of $sim$ 12,400 deg$^2$ in the Southern Hemisphere. The spectr
We investigate the extent to which the Palomar-Green (PG) Bright Quasar Survey (BQS) is complete and representative of the general quasar population by comparing with imaging and spectroscopy from the Sloan Digital Sky Survey. A comparison of SDSS an
The source catalogue for the LBQS and the FIRST Survey are compared in their regions of overlap. In the 270 deg^2 common to both surveys the LBQS contains ~100,000 stellar and ~40,000 non-stellar objects, while the FIRST catalogue contains ~25,000 so