Related papers: The UVX quasar optical luminosity function and its…

We present the rest-frame Ultra-Violet (UV) galaxy luminosity function (LF) and luminosity density (LD) measurements in the far-UV (150 nm) wavelength, in the redshift range z = 0.6 - 1.2. The UV LF is derived using XMM-Newton Optical…

We combine ultraviolet imaging of the 13H survey field, taken with the XMM-Newton Optical Monitor telescope (XMM-OM) and the Neil Gehrels Swift Observatory Ultraviolet and Optical Telescope (UVOT) in the UVM2 band, to measure rest-frame…

We match quasars discovered in a multi-color survey centered on the northern Hubble Deep Field (HDF) with radio sources from an ultra-deep radio survey. Although 3 out of 12 quasars are detected at a level below 0.2 mJy at 1.4 GHz, all of…

Quasar redshifts require the best possible precision and accuracy for a number of applications, such as setting the velocity scale for outflows as well as measuring small-scale quasar-quasar clustering. The most reliable redshift standard…

We present a new determination of the evolving galaxy UV luminosity function (LF) over the extreme redshift range $12.5<z<18.5$, based on a wide-area search of $>$0.6 deg$^2$ of JWST NIRCam imaging containing $>150$ independent sight-lines.…

We present the galaxy optical luminosity function for the redshift range 0.05<z<0.75 from the AGN and Galaxy Evolution Survey (AGES), a spectroscopic survey of 7.6 sq. deg. in the Bootes field of the NOAO Deep Wide-Field Survey. Our…

UBVR photometry of a sample of B3-VLA radio quasars, about 80 per cent complete, is used to analyse their spectral energy distribution (SED). The SEDs are generally well fitted with power-laws, with an average slope alpha=-0.39 (S_nu propto…

We investigate the evolution of the universal rest-frame ultraviolet luminosity density from z = 1.5 to the present. We analyze an extensive sample of multicolor data (U', B, V = 24.5) plus spectroscopic redshifts from the Hawaii Survey…

We present a model for the evolution of the galaxy ultraviolet (UV) luminosity function (LF) across cosmic time where star formation is linked to the assembly of dark matter halos under the assumption of a mass dependent, but redshift…

We present the results for the galaxy luminosity function as estimated from the Durham/UKST Galaxy Redshift Survey. This survey is magnitude limited to bj = 17, contains 2500 galaxies sampled at a rate of one in three and surveys a 4 x 10^6…

At bright radio powers ($P_{\rm 1.4 GHz} > 10^{25}$ W/Hz) the space density of the most powerful sources peaks at higher redshift than that of their weaker counterparts. This paper establishes whether this luminosity-dependent evolution…

Low-frequency radio surveys are ideal for selecting orientation-independent samples of extragalactic sources because the sample members are selected by virtue of their isotropic steep-spectrum extended emission. We use the new 7C Redshift…

Recent discoveries by the Sloan Digital Sky Survey (SDSS) of four bright redshift z=6 quasars could constrain the mechanism by which the supermassive black holes powering these sources are assembled. Here we compute the probability that the…

We present a new method to test the cosmological model, based on the non-linear relation between ultraviolet and X-ray luminosity of quasars. We built a data set of ~1,138 quasars by merging several literature samples with X-ray…

Using a sample of optically-selected quasars from the Sloan Digital Sky Survey, we have determined the radio-loud fraction (RLF) of quasars as a function of redshift and optical luminosity. The sample contains more than 30,000 objects and…

We present measurements of the rest-frame ultraviolet luminosity function (UVLF) in three redshift bins over $z\sim5.5$-14 from the JWST COSMOS-Web survey. Our samples, selected using the dropout technique in the HST/ACS F814W, JWST/NIRCam…

Luminous high-redshift quasars can be used to probe of the intergalactic medium (IGM) in the early universe because their UV light is absorbed by the neutral hydrogen along the line of sight. They help us to measure the neutral hydrogen…

A complete sample of 659 field galaxies with 17.0$<$U$\leq$21.1, each with U-B-V-R-I7500-I8600 photometry, has been selected from a deep field survey which covers 0.83 deg$^2$ along six lines of sight (Hall et al. 1996a). Each galaxy's…

Over the past decades, nearly a million quasars have been explored to shed light on the evolution of supermassive black holes and galaxies. The ultraviolet-to-optical spectra of type-1 quasars particularly offer insights into their black…

In this paper, based on a 2.29 GHz VLBI all-sky survey of 613 milliarcsecond ultra-compact radio sources with $0.0035<z<3.787$, we describe a method of identifying the sub-sample which can serve as individual standard rulers in cosmology.…