We present measurements of black hole masses and Eddington ratios (λ Edd) for a sample
of 38 bright (M 1450<− 24.4 mag) quasars at 5.8≲ z≲ 7.5, derived from Very Large …

We present the z≈ 6 type-1 quasar luminosity function (QLF), based on the Pan-STARRS1
(PS1) quasar survey. The PS1 sample includes 125 quasars at z≈ 5.7–6.2, with− 28≲ M …

This is the third paper in a series aimed at finding reionization-era quasars with the
combination of DESI Legacy imaging Surveys (DELS), the Pan-STARRS1 (PS1) Survey …

We report the spectroscopic follow-up of 175 lensed quasar candidates selected using Gaia
Data Release 2 observations following Paper III of this series. Systems include 86 confirmed …

The study of the space density of bright active galactic nuclei (AGNs) at z> 4 has been
subject to extensive effort given its importance in the estimation of cosmological ionizing …

We present the first results from a new survey for high-redshift (z≳ 5) gravitationally lensed
quasars and close quasar pairs. We carry out candidate selection based on the colors and …

Faint z∼ 5 quasars with M 1450∼− 23 mag are known to be potentially important
contributors to the ultraviolet ionizing background in the postreionization era. However, their …

Context. The KiDS Strongly lensed QUAsar Detection project (KiDS-SQuaD) is aimed at
finding as many previously undiscovered gravitational lensed quasars as possible in the …

It is widespread opinion that hydrogen reionization is mainly driven by primeval star-forming
galaxies, with high-z active galactic nuclei (AGNs) having a minor role. Recent observations …

We introduce a probabilistic approach to select 6≤≤ 8 quasar candidates for spectroscopic
follow-up, which is based on density estimation in the high-dimensional space inhabited by …