Discovery of 178 Giant Radio Galaxies in 1059 deg${}^2$ of the Rapid ASKAP Continuum Survey at 888 MHz

Abstract

We report the results of a visual inspection of images of the Rapid ASKAP Continuum Survey (RACS) in search of extended radio galaxies (ERG) that reach or exceed linear sizes on the order of one Megaparsec. We searched a contiguous area of 1059deg${}^2$ from RA${}_{\mathrm{J}}$=20${}^h$20${}^m$ to 06${}^h$20${}^m$, and $-50^{\circ }<{\mathrm{Dec}}_{\mathrm{J}}<-40^{\circ }$, which is covered by deep multi-band optical images of the Dark Energy Survey (DES), and in which previously only three ERGs larger than 1Mpc had been reported. For over 1800 radio galaxy candidates inspected, our search in optical and infrared images resulted in hosts for 1440 ERG, for which spectroscopic and photometric redshifts from various references were used to convert their largest angular size (LAS) to projected linear size (LLS). This resulted in 178 newly discovered giant radio sources (GRS) with LLS$>$1Mpc, of which 18 exceed 2Mpc and the largest one is 3.4Mpc. Their redshifts range from 0.02 to $\sim$2.0, but only 10 of the 178 new GRS have spectroscopic redshifts. For the 146 host galaxies the median $r$-band magnitude and redshift are 20.9 and 0.64, while for the 32 quasars or candidates these are 19.7 and 0.75. Merging the six most recent large compilations of GRS results in 458 GRS larger than 1Mpc, so we were able to increase this number by $\sim 39\%$ to now 636.

arXiv comment27 pages, 8 figures, two tables. Published in Galaxies, vol. 9, 99, special issue with contributions from the conference "A New Window on the Radio Emission from Galaxies, Galaxy Clusters and Cosmic Web: Current Status and Perspectives" see https://www.mdpi.com/journal/galaxies/special_issues/nonthermal_galaxycluster. An ASCII version of Table 2 is included

References in corpus (32)

• Gaia Data Release 2. Summary of the contents and survey properties
• The 2dF Galaxy Redshift Survey: Spectra and redshifts
• The Sixteenth Data Release of the Sloan Digital Sky Surveys: First Release from the APOGEE-2 Southern Survey and Full Release of eBOSS Spectra
• A Cosmology Calculator for the World Wide Web
• The 6dF Galaxy Survey: Final Redshift Release (DR3) and Southern Large-Scale Structures
• GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey I: A low-frequency extragalactic catalogue
• The LOFAR Two Meter Sky Survey: Deep Fields, I -- Direction-dependent calibration and imaging
• Revisiting the Fanaroff-Riley dichotomy and radio-galaxy morphology with the LOFAR Two-Metre Sky Survey (LoTSS)
• The Clustering of DESI-like Luminous Red Galaxies Using Photometric Redshifts
• The Rapid ASKAP Continuum Survey Paper II: First Stokes I Source Catalogue Data Release
• The Phoenix Deep Survey: The 1.4 GHz microJansky catalogue
• Radio Galaxy Zoo: host galaxies and radio morphologies derived from visual inspection
• FRII{\sl{CAT}}: A FIRST catalog of FR~II radio galaxies
• Search and analysis of giant radio galaxies with associated nuclei (SAGAN) -- I : New sample and multi-wavelength studies
• J1420--0545: The radio galaxy larger than 3C236
• Alignments of Radio Galaxies in Deep Radio Imaging of ELAIS N1
• Catalogues of Active Galactic Nuclei From Gaia and unWISE Data
• Remnant radio-loud AGN in the Herschel-ATLAS field
• The intergalactic magnetic field probed by a giant radio galaxy
• A catalogue of clusters of galaxies identified from all sky surveys of 2MASS, WISE, and SuperCOSMOS
• Discovery of Giant Radio Galaxies from NVSS: Radio & Infrared Properties
• Radio Galaxy Zoo: A Search for Hybrid Morphology Radio Galaxies
• Radio observations of the merging galaxy cluster system Abell 3391-Abell 3395
• J1649+2635: A Grand-Design Spiral with a Large Double-Lobed Radio Source
• Radio Sources in the Nearby Universe
• The WaZP galaxy cluster sample of the Dark Energy Survey Year 1
• Radio luminosity function of brightest cluster galaxies
• Radio Galaxy Zoo: Cosmological Alignment of Radio Sources
• What sparks the radio-loud phase of nearby quasars?
• MALS-NOT: Identifying Radio-Bright Quasars for the MeerKAT Absorption Line Survey
• The Million Quasars (Milliquas) v7.2 Catalogue, now with VLASS associations. The inclusion of SDSS-DR16Q quasars is detailed
• Statistics of Hotspots in Radio Galaxies