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Related papers: Optically Faint Microjansky Radio Sources

200 papers

We present Spitzer photometric data for a complete sample of 19 low redshift (z<0.1) 3CRR radio galaxies as part of our efforts to understand the origin of the prodigious mid- to far-infrared (MFIR) emission from radio-loud AGN. Our results…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 D. Dicken , C. Tadhunter , D. Axon , A. Robinson , R. Morganti , P. Kharb

All very massive early-type galaxies contain supermassive blackholes but are these blackholes all sufficiently active to produce detectable radio continuum sources? We have used the 887.5~MHz Rapid ASKAP Continuum Survey DR1 to measure the…

Astrophysics of Galaxies · Physics 2024-01-05 Michael J. I. Brown , Teagan A. Clarke , Andrew M. Hopkins , Ray P. Norris , T. H. Jarrett

We present and discuss two catalogues of UV-selected (NUV $< 22.8$ mag) galaxies that lie within a 200 deg$^2$ area of sky covered by the ASKAP FLASH survey and have an impact parameter of less than 20 arcsec to a FLASH radio continuum…

Astrophysics of Galaxies · Physics 2024-11-15 Sophie L. Eden , Elaine M. Sadler , Kevin A. Pimbblet , Elizabeth K. Mahony , Hyein Yoon

High-redshift radio sources provide plentiful opportunities for studying the formation and evolution of early galaxies and supermassive black holes. However, the number of known radio-loud active galactic nuclei (AGN) above redshift 4 is…

Astrophysics of Galaxies · Physics 2022-06-29 M. Krezinger , K. Perger , K. É. Gabányi , S. Frey , L. I Gurvits , Zs. Paragi , T. An , Y. Zhang , H. Cao , T. Sbarrato

As part of a large study to investigate the nature of the longer wavelength continuum emission of radio-loud AGN, we present new mid to far-infrared (MFIR) and high frequency radio observations for a complete sample of 2Jy powerful,…

Astrophysics · Physics 2009-11-13 D. Dicken , C. Tadhunter , R. Morganti , C. Buchanan , T. Oosterloo , D. Axon

We have obtained redshifts and infrared images for a sample of faint B2/6C radio sources whose fluxes are about six times fainter than those of sources in the bright 3C sample. We now have unambiguous redshifts for 90% of the sources,…

Astrophysics · Physics 2015-06-24 Stephen Eales , Steve Rawlings , Duncan Law-Green , Garret Cotter , Mark Lacy

(abridged) We study the composition of the faint radio population selected from the VLA-COSMOS 3GHz Large Project. The survey covers a 2.6sq.deg. area with a mean rms of ~2.3uJy/b, cataloging 10830 sources (>5sigma). Combining these radio…

We use a physically motivated semi-analytic model, based on the mass function of dark matter halos, to predict the number of radio-loud quasars as a function of redshift and luminosity. Simple models in which the central BH mass scales with…

Astrophysics · Physics 2009-11-10 Zoltan Haiman , Eliot Quataert , Geoffrey C. Bower

We present spectra for a sample of radio sources from the FIRST survey, and use them to define the form of the redshift distribution of radio sources at mJy levels.We targeted 365 sources and obtained 46 redshifts (13 per cent of the…

Astrophysics · Physics 2009-10-31 M. Magliocchetti , S. J. Maddox , J. V. Wall , C. R. Benn , G. Cotter

Optically--faint X-ray sources (those with f_X/f_R > 10) constitute about 20% of X-ray sources in deep surveys, and are potentially highly obscured and/or at high redshift. Their faint optical fluxes are generally beyond the reach of…

The mJy variable extragalactic radio sky is known to be broadly non-changing with approximately $3\%$ of persistent radio sources exhibiting variability which is largely AGN-related. In the faint (<mJy) flux density regime, it is widely…

We report 20 and 6 cm VLA deep observations of the CDF-S including the Extended CDF-S. We discuss the radio properties of 266 cataloged radio sources, of which 198 are above a 20 cm completeness level reaching down to 43 microJy at the…

Astrophysics · Physics 2009-11-13 K. I. Kellermann , E. B. Fomalont , V. Mainieri , P. Padovani , P. Rosati , P. Shaver , P. Tozzi , N. Miller

We report the identification of radio (0.144-3 GHz), mid-IR, far-IR, and sub-mm (24-850$\mu$m) emission at the position of one of 41 UV-bright (M$_\mathrm{UV}^{}\lesssim-21.25$) $z\simeq6.6-6.9$ Lyman-break galaxy candidates in the 1.5…

High-redshift radio-loud quasars are used to, among other things, test the predictions of cosmological models, set constraints on black hole growth in the early universe and understand galaxy evolution. Prior to this paper, 20 extragalactic…

We investigate the properties of the most optically faint sources in the GOODS-N area (R > 26.5 AB). Such extremely optically faint populations present an uncharted territory despite the fact that they represent an appreciable fraction of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 E. Rovilos , I. Georgantopoulos , A. Akylas , S. Fotopoulou

High-redshift quasars are important to study galaxy and active galactic nuclei (AGN) evolution, test cosmological models, and study supermassive black hole growth. Optical searches for high-redshift sources have been very successful, but…

It has been speculated that low luminosity radio-loud AGN have the potential to serve as an important source of AGN feedback, and may be responsible for suppressing star-formation activity in massive elliptical galaxies at late times. As…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 K. McAlpine , M. J. Jarvis , D. G. Bonfield

We present the radio and X-ray properties of 1.2 mm MAMBO source candidates in a 1600 sq. arcmin field centered on the Abell 2125 galaxy cluster at z=0.247. The brightest, non-synchrotron mm source candidate in the field has a photometric…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-24 Jeff Wagg , Frazer Owen , Frank Bertoldi , Maike Sawitzki , Christopher L. Carilli , Karl M. Menten , Hauke Voss

We have combined a survey at 24 microns to 0.3 mJy with the Multiband Imaging Photometer (MIPS) on the Spitzer Space Telescope, a 20 cm A-array VLA survey covering 0.5 deg^2, and an existing 172 ks Chandra X-Ray Observatory exposure to…

I report detections of four new HI 21-cm absorbers associated with sources at intermediate redshifts, 0.7 < z < 1.0. The sources are part of a sample of 11 radio-loud galaxies, all at 0.7 < z < 1.0, that were searched for associated HI…

Astrophysics of Galaxies · Physics 2018-11-28 J. N. H. S. Aditya