First results from the Isaac Newton Telescope Wide Angle Survey: The z>5 quasar survey

Abstract

We report the first results of an observational program designed to determine the luminosity density of high redshift quasars (z > 5 quasars) using deep multi-colour CCD data. We report the discovery and spectra of 3 i < 21.5 high redshift (z > 4.4) quasars, including one with z > 5. At z=5.17, this is the fourth highest redshift quasar currently published. Using these preliminary results we derive an estimate of the M \rm_B < - 25.0 (M \rm_{AB1450} < - 24.5) quasar space density in the redshift range 4.8 < z < 5.8 of 3.6 \pm2.5\times 10^{-8} \Mpc ^{-3} . When completed the survey will provide a firm constraint on the contribution to the ionizing UV background in the redshift range 4.5 - 5.5 from quasars by determining the faint end slope of the quasar luminosity function. The survey uses imaging data taken with the 2.5m Isaac Newton Telescope as part of the Public Isaac Newton Group Wide Field Survey (WFS). This initial sample of objects is taken from two fields of effective area $\sim 12.5de{g}^2$ from the final $\sim 100de{g}^2$.

5 pages, 5 figures, accepted for publication MNRAS. Note: Revised version with quasar space density estimate and survey completeness information

Cited by in corpus (17)

• The Sloan Digital Sky Survey Quasar Catalog I. Early Data Release
• Spectral Energy Distributions of QSOs at z>5: common AGN-heated dust and occasionally strong star-formation
• Quasar Elemental Abundances at High Redshifts
• Sensitive observations at 1.4 and 250 GHz of z > 5 QSOs
• Faint AGN and the Ionizing Background
• Dust emission and star formation toward a redshift 5.5 QSO
• Reddening-Independent Quasar Selection from a Wide-Field Optical and Near-IR Imaging Survey
• The radio spectral turnover of radio-loud quasars at $z>5$
• Identifying quasars with astrometric and mid-infrared methods from APOP and ALLWISE
• Observations by GMRT at 323 MHz of radio-loud quasars at $z>5$
• High-redshift QSOs in the FIRST survey
• The Infrared Medium-deep Survey. III. Survey of Luminous Quasars at 4.7 $\le$ z $\le$ 5.4
• QSOs from the variability and proper motion survey in the M3 field
• A QSO survey via optical variability and zero proper motion in the M92 field. IV. More QSOs due to improved photometry
• SQUAB I: The first release of Strange QUasar candidates with ABnormal astrometric characteristics from Gaia EDR3 and SDSS
• A survey for low luminosity quasars at redshift z~5
• The BTC40 Survey for Quasars at 4.8 < z < 6