Related papers: Extensions around z=2 QSOs
Links between the properties of radio-loud active galactic nuclei (RLAGNs) and the morphology of their hosts may provide important clues for our understanding of how RLAGNs are triggered. In this work, focusing on passive galaxies, we study…
We present clustering results from the 2dF QSO Redshift Survey (2QZ) which currently contains over 20,000 QSOs at z<3. The two-point correlation function of QSOs averaged over the entire survey (<z>~1.5) is found to be similar to that of…
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…
We observed a small sample of 5 radio-quiet QSOs with integral field spectroscopy to search for possible extended emission in the Ly$\alpha$ line. We subtracted the QSO point sources using a simple PSF self-calibration technique that takes…
We present new data on several z=1.54 radio-loud quasar fields from a sample of 31 at z=1-2 in which we have previously identified an excess population of predominantly red galaxies. Narrow-band H-alpha observations detect five candidate…
We present VLT near-IR spectroscopic observations of three X-ray sources characterized by extremely high X-ray-to-optical ratios (X/O>40), extremely red colors (6.3<R-K<7.4, i.e. EROs) and bright infrared magnitudes (17.6<K<18.3). These…
Images from recent radio surveys were used to determine the radio position angles for over 2000 extended radio galaxies with host galaxies brighter than m$_{r}\sim$18 mag. For 1509 of these their optical axis ratios were obtained, and for a…
We present measurements of the clustering properties of galaxies in the field of redshift range $0.5 \lesssim z \lesssim 1.5$ Ultra Steep Spectrum (USS) radio sources selected from Sydney University Molonglo Sky Survey and NRAO VLA Sky…
Recent highly sensitive detections of line emission from extended gas in the local universe demonstrate the feasibility of detecting H$\alpha$ emitting galactic halos out to $z\sim1$. We determine the form of the surface brightness vs.…
Ground-based high spatial-resolution optical and near-IR imaging at BIHK' is presented for a complete sample of optically selected Palomar-Green QSOs which have infrared excesses at least as great as those of "warm" AGN-like ultraluminous…
Context: Narrow-band surveys for Ly-alpha emitters (LAEs) is a powerful tool in detecting high, and very high, redshift galaxies. Even though samples are growing at redshifts z = 3 - 6, the nature of these galaxies is still poorly known.…
We present near-infrared imaging with ESO VLT+ISAAC of the host galaxies of low luminosity quasars in the redshift range 1 < z < 2, aimed at investigating the relationship between the nuclear and host galaxy luminosities at high redshift.…
Several recent studies show that bright, intermediate and high redshift optically and radio selected QSOs are positively correlated with nearby galaxies on a range of angular scales up to a degree. Obscuration by unevenly distributed…
We present new mid-infrared and submillimetre observations for a sample of eight high redshift type-2 QSOs located in the Chandra Deep Field South. The sources are X-ray absorbed with luminosities in excess of 10^44 erg/s. Two of the…
Extended Ly$\alpha$ emission is routinely found around single quasars (QSO) across cosmic time. However, few studies have investigated how such emission changes in fields with physically associated QSO pairs, which should reside in dense…
We have conducted a long slit search for low surface brightness Lyman-alpha emitters at redshift 2.67 < z < 3.75. A 92 hour long exposure with VLT/FORS2 down to a 1-sigma surface brightness detection limit of 8x10^-20 erg/cm2/s/sqarcsec…
We report the discovery of a group of galaxies at redshift 2.38. We imaged about 10% of a claimed supercluster of QSO absorption-lines at z=2.38 (Francis & Hewett 1993). In this small field (2 arcmin radius) we detect two Ly-alpha emitting…
The results of analysis of HST I-band imaging of a sample of 41 radio galaxies spanning three orders of magnitude in radio luminosity at redshift z~0.5 are presented. The full sample is drawn from four complete, low-frequency selected radio…
We present integral field spectrograph (IFS) with laser guide star adaptive optics (LGS-AO) observations of z=2 quasi-stellar objects (QSOs) designed to resolve extended nebular line emission from the host galaxy. Our data was obtained with…
We present a sample of $i_{775}$-dropout candidates identified in five Hubble Advanced Camera for Surveys fields centered on Sloan Digital Sky Survey QSOs at redshift $z\sim 6$. Our fields are as deep as the Great Observatory Origins Deep…