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Related papers: Optically Faint Microjansky Radio Sources

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The study of the nature of faint radio sources is of great importance since a significant fraction of these objects is thought to be composed of actively star-forming galaxies. Due to the increased sensitivity of radio telescopes, we are…

Astrophysics · Physics 2007-05-23 J. Afonso , B. Mobasher , A. Hopkins , L. Cram

We present a deep 1.4 GHz survey made with the Australia Telescope Compact Array (ATCA), having a background RMS of 9 microJy near the image phase centre, up to 25 microJy at the edge of a 50' field of view. Over 770 radio sources brighter…

Astrophysics · Physics 2009-10-31 A. Hopkins , J. Afonso , L. Cram , B. Mobasher

We use deep multi-colour (UBVRIJK) images mostly taken in the framework of the ESO Deep Public Survey (DPS) to optically identify and derive photometric redshifts for a complete sample of 131 radio sources with S>0.4 mJy, observed at both…

Showing 1.4 GHz flux densities in the range of a few to a few tens of mJy, infrared-faint radio sources (IFRS) are a type of galaxy characterised by faint or absent near-infrared counterparts and consequently extreme radio-to-infrared flux…

Astrophysics of Galaxies · Physics 2015-07-22 Andreas Herzog , Ray P. Norris , Enno Middelberg , Lee R. Spitler , Christian Leipski , Quentin A. Parker

We describe an observational program aimed at understanding the radio emission from distant, rapidly evolving galaxy populations. These observations were carried out at 1.4 and 8.5 GHz with the VLA centered on the Hubble Deep Field,…

Astrophysics · Physics 2009-10-31 E. A. Richards

Infrared-Faint Radio Sources (IFRS) represent an unexpected class of objects relatively bright at radio wavelength, but unusually faint at infrared (IR) and optical wavelengths. A recent and extensive campaign on the radio-brightest IFRSs…

VLBI now has the capability of imaging relatively large fields-of-view (~ 5 arcmin sq) with sub-mJy detection limits. In principle such observations can distinguish between starburst and AGN activity in cosmologically distant sources. We…

Astrophysics · Physics 2009-11-06 M. A. Garrett , T. W. B. Muxlow , S. T. Garrington

We present optical identifications and redshifts for seventeen new high-redshift radio sources. Fifteen of these sources are radio galaxies; the remaining two are high-redshift, steep-spectrum, radio-loud quasars. These objects were…

I describe an observational program aimed at understanding the radio emission from distant, rapidly evolving galaxy populations. These observations were carried out at 1.4 and 8.5 GHz with the VLA centered on the Hubble Deep Field. Further…

Astrophysics · Physics 2009-10-31 E. A. Richards

We present a detailed analysis of 256 radio sources from our deep (flux density limit of 42 microJy at the field centre at 1.4 GHz) Chandra Deep Field South 1.4 and 5 GHz VLA survey. The radio population is studied by using a wealth of…

Astrophysics · Physics 2011-02-11 P. Padovani , V. Mainieri , P. Tozzi , K. I. Kellermann , E. B. Fomalont , N. Miller , P. Rosati , P. Shaver

Infrared-faint radio sources (IFRS) are objects that have flux densities of several mJy at 1.4GHz, but that are invisible at 3.6um when using sensitive Spitzer observations with uJy sensitivities. Their nature is unclear and difficult to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Enno Middelberg , Ray P. Norris , Christopher A. Hales , Nick Seymour , Melanie Johnston-Hollitt , Minh T. Huynh , Emil Lenc , Minnie Y. Mao

We present deep, wide-field European VLBI Network (EVN) 1.6 GHz observations of the Hubble Deep Field (HDF) region with a resolution of 0.025 arcseconds. Above the 210 microJy/beam (5sigma) detection level, the EVN clearly detects two radio…

Astrophysics · Physics 2007-05-23 M. A. Garrett , T. W. B. Muxlow , S. T. Garrington

A 10-arcmin field around the HDF(N) contains 92 radio sources >40 uJy, resolved by MERLIN+VLA at 0".2-2".0 resolution. 55 have Chandra X-ray counterparts including 18 with a hard X-ray photon index and high luminosity characteristic of a…

We present spectra and near-infrared images of a sample of faint radio sources initially selected as promising high-redshift radio galaxy (HzRG) candidates. We have determined redshifts for a total of 13 radio galaxies with redshifts…

Spectra have been obtained with the Infrared Spectrograph on the Spitzer Space Telescope for 18 optically faint sources (R > 23.9,mag) having f(nu) (24um) > 1.0,mJy and having radio detections at 20 cm to a limit of 115 microJy. Sources are…

Astrophysics · Physics 2009-11-13 D. W. Weedman , E. Le Floc'h , S. J. U. Higdon , J. L. Higdon , J. R. Houck

We present the multiwavelength properties of 266 cataloged radio sources identified with 20 and 6 cm VLA deep observations of the CDFS at a flux density limit of 42 \mu Jy at the field centre at 1.4 GHz. These new observations probe the…

Cosmology and Nongalactic Astrophysics · Physics 2009-03-25 P. Tozzi , K. Kellermann , E. Fomalont , N. Miller , C. Norman , V. Mainieri , P. Padovani , P. Rosati , the VLA-CDFS team

We present MIPS 24 micron observations of the Hubble Deep Field South taken with the Spitzer Space Telescope. The resulting image is 254 arcmin^2 in size and has a sensitivity ranging between ~12 to ~30 microJy rms, with a median…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-30 M. T. Huynh , E. Gawiser , D. Marchesini , G. Brammer , L. Guaita

Using a deep Australia Telescope Compact Array (ATCA) radio survey covering an area of ~3deg^{2} to a 4\sigma sensitivity of \ge 100 \muJy at 1.4GHz, we study the nature of faint radio galaxies. About 50% of the detected radio sources are…

Astrophysics · Physics 2009-10-31 A. Georgakakis , B. Mobasher , L. Cram , A. Hopkins , C. Lidman , M. Rowan-Robinson

Study of high-redshift radio galaxies (HzRGs) can shed light on the active galactic nuclei (AGNs) evolution in massive elliptical galaxies. The vast majority of observed high-redshift AGNs are quasars, and there are very few radio galaxies…