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The Second APM UKST Colour Survey for z>4 Quasars

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TLDR
In this article, the authors presented the spectra, positions, and finding charts for 31 bright (R 4.5) quasars in the UK or POSSII Schmidt Plates scanned at the Automated Plate Measuring facility in Cambridge.
Abstract
We present the spectra, positions, and finding charts for 31 bright (R 4.5. The majority are in the southern sky (dec 2.5) colours from UK or POSSII Schmidt Plates scanned at the Automated Plate Measuring facility in Cambridge. Low resolution (~> 10A) spectra were obtained to identify the quasars, primarily at the Las Campanas Observatory. The highest redshift quasar in our survey is at z ~ 4.8 (R = 18.7) and its spectrum shows a damped Lyman-alpha absorption system at z = 4.46. This is currently the highest redshift damped Lyman-alpha absorber detected. Five of these quasars exhibit intrinsic broad absorption line features. Combined with the previously published results from the first part of the APM UKST survey we have now surveyed a total of ~8000 squ deg of sky i.e. 40% of the high galactic latitude (|b|>30 deg) sky, resulting in 59 optically selected quasars in the redshift range 3.85 to 4.78; 49 of which have z>=4.00.

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Journal ArticleDOI

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

TL;DR: In this paper, the luminosity density of high redshift quasars (z > 5) using deep multi-colour CCD data has been determined using an observational program.
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