Related papers: Extragalactic large-scale structures in the northe…
Radio observations were used to detect the `active' galaxy population within rich clusters of galaxies in a non-biased manner that is not plagued by dust extinction or the K-correction. We present wide-field radio, optical (imaging and…
Low-frequency radio observations of galaxy clusters are the key to detecting the diffuse extended emission associated with them. The presence and properties of such radio sources in galaxy clusters reveal the existence of magnetic fields on…
We report the discovery of a galaxy overdensity around a Compton-thick Fanaroff-Riley type II (FRII) radio galaxy at z=1.7 in the deep multiband survey around the z=6.3 QSO SDSS J1030+0524. Based on a 6hr VLT/MUSE and on a 4hr LBT/LUCI…
We have carried out optical spectroscopy with the Anglo-Australian Telescope for 24,726 objects surrounding a sample of 19 Giant Radio Galaxies (GRGs) selected to have redshifts in the range 0.05 to 0.15 and projected linear sizes from 0.8…
A narrowband imaging survey of 276 square minutes of arc was carried out at near infrared wavelengths to search for emission line objects at high redshifts. Most of the fields contained a known quasar or radio galaxy at a redshift that…
During the start of a survey program using FORS2 long slit spectroscopy on planetary nebulae (PN) and their haloes, we serendipitously discovered six background emission line galaxies (ELG) with redshifts of z = 0.2057, 0.3137, 0.37281,…
We report spectroscopic redshifts for 18 microJy-radio galaxies at mean redshift of z=2.2 that are faint at both submmillimeter (submm) and optical wavelengths. While the radio fluxes of these galaxies could indicate far-infrared (far-IR)…
We report the first results from the Z-FOURGE survey: the discovery of a candidate galaxy cluster at z = 2.2 consisting of two compact overdensities with red galaxies detected at >20{\sigma} above the mean surface density. The discovery was…
Clusters of galaxies are at the intersection of cosmic filaments and are still accreting galaxies and groups along these preferential directions, but, because of their relatively low contrast on the sky, they are difficult to detect (unless…
We cross-identified the ROSAT Bright Source Catalog (RBSC) and the NRAO VLA Sky Survey (NVSS) to construct the RBSC-NVSS sample of the brightest X-ray sources (>= 0.1 counts/s or ~1E-12 ergs/cm/cm/s in the 0.1-2.4 keV band) that are also…
An extraordinarily massive cluster of red supergiants has been recently reported in the direction of the galactic coordinates $l = 25\rlap.^\circ3$; $b = -0\rlap.^\circ2$. This cluster is associated with an X-ray source, a very high-energy…
We present the first detections of CH3SH, C3H+, C3N, HCOOH, CH2CHCN, and H2CN in an extragalactic source. Namely the spiral arm of a galaxy located at z=0.89 on the line of sight to the radio-loud quasar PKS 1830-211. OCS, SO2, and NH2CN…
We report the discovery of a galaxy overdensity at z=1.11 associated with the z=1.110 high-redshift radio galaxy MG0442+0202. The group, CL0442+0202, was found in a near-infrared survey of z>1 radio galaxies undertaken to identify…
Radio galaxies are uniquely useful as probes of large-scale structure as their uniform identification with giant elliptical galaxies out to high redshift means that the evolution of their bias factor can be predicted. As the initial stage…
High redshift quasars ($z>5$) that also shine brightly at radio wavelengths are unique signposts of supermassive black hole activity in the early universe. However, bright radio sources at $z\ge5$ are extremely rare and therefore we have…
We present a novel method to estimate accurate redshifts of star-forming galaxies by measuring the flux ratio of the same emission line observed through two adjacent narrow-band filters. We apply this method to our NB912 and new NB921 data…
Results of optical identification of the ASCA Lynx deep survey are presented. Six X-ray sources are detected in the 2-7 keV band using the SIS in a 20'x20' field of view with fluxes larger than ~4x10^{-14} erg s-1 cm-2 in the band.…
We present the results of an observing program with the SCUBA bolometer array to measure the submillimetre (submm) dust continuum emission of 24 distant (z > 1) radio galaxies. We detected submm emission in 12 galaxies with S/N > 3,…
We present a spectroscopic catalogue of 40 luminous starburst galaxies at z=0.7--1.7 (median z=1.3). 19 of these are submillimetre galaxies (SMGs) and 21 are submillimetre-faint radio galaxies (SFRGs). This sample helps to fill in the…
Since radio sources with Ultra Steep Spectra (USS; alpha <~ -1.30; S ~ nu^alpha) are efficient tracers of high redshift radio galaxies (HzRGs), we have defined three samples of such USS sources using the recently completed WENSS, TEXAS,…