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Related papers: The Parkes Half-Jansky Flat-Spectrum Sample

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This paper describes the selection of a new southern/equatorial sample of Gigahertz Peaked Spectrum (GPS) radio galaxies, and subsequent optical CCD imaging and spectroscopic observations using the ESO 3.6m telescope. The sample consists of…

Astrophysics · Physics 2009-11-07 I. A. G. Snellen , M. D. Lehnert , M. N. Bremer , R. T. Schilizzi

Gigahertz Peaked Spectrum (GPS) radio galaxies are generally thought to be the young counterparts of classical extended radio sources. Statistically complete samples of GPS sources are vital for studying the early evolution of radio-loud…

Astrophysics · Physics 2009-11-13 N. de Vries , I. A. G. Snellen , R. T. Schilizzi , M. D. Lehnert , M. N. Bremer

We present optical spectra and redshift measurements for 178 flat-spectrum objects from the Parkes quarter-Jansky flat-spectrum sample. These spectra were obtained in order to compile a complete sample of quasars for use in a study of…

Astrophysics · Physics 2009-11-07 I. M. Hook , P. A. Shaver , C. A. Jackson , J. V. Wall , K. I. Kellermann

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,…

Astrophysics · Physics 2011-05-23 Carlos De Breuck , Wil van Breugel , Huub Rottgering , George Miley

This paper introduces a new program to find high-redshift radio galaxies in the southern hemisphere through ultra-steep spectrum (USS) selection. We define a sample of 234 USS radio sources with spectral indices alpha_408^843 < -1.0 and…

Astrophysics · Physics 2009-11-13 J. W. Broderick , J. J. Bryant , R. W. Hunstead , E. M. Sadler , T. Murphy

As a pilot study for the first all-sky radio survey at short wavelengths, we have observed 1216 sq. deg. of the southern sky at 18GHz (16mm) using a novel wide-band (3.4GHz bandwidth) analogue correlator on one baseline of the Australia…

Infrared 3.6 to 8 micron images of the Extended Groth Strip yield plausible counterpart identifications for all but one of 510 radio sources in the AEGIS20 S(1.4 GHz) > 50 micro-Jy sample. This is the first such deep sample that has been…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-30 S. P. Willner , M. L. N. Ashby , P. Barmby , S. C. Chapman , A. Coil , M. Cooper , J. -S. Huang , R. Ivison , D. C. Koo

The redshift distribution of flat-spectrum radio sources with 5 GHz flux densities S>5 mJy is a key component in using current radio lens surveys to probe the cosmological model. We have constructed the first flat-spectrum radio sample in…

Astrophysics · Physics 2009-11-07 J. A. Munoz , E. E. Falco , C. S. Kochanek , J. Lehar , E. Mediavilla

We present optical spectroscopic data for a complete sample of 161 S_5GHz >= 0.2 Jy, flat-spectrum radio sources. The sources were observed as part of a survey for high redshift, radio-loud quasars, and were selected for spectroscopic…

Astrophysics · Physics 2015-06-24 I. M. Hook , R. G. McMahon , M. J. Irwin , C. Hazard

We present basic observational data on the 6C** sample. This is a new sample of radio sources drawn from the 151 MHz 6C survey, which was filtered with radio criteria chosen to optimize the chances of finding radio galaxies at z > 4. The…

The Australia Telescope 20 GHz (AT20G) survey is a blind survey of the whole Southern sky at 20 GHz with follow-up observations at 4.8, 8.6, and 20 GHz carried out with the Australia Telescope Compact Array (ATCA). In this paper we present…

The results of an optical and infrared investigation of a radio sample drawn from the 1.4 GHz Leiden-Berkeley Deep Survey are presented. This is believed to be the most comprehensive sample of radio sources at millijansky flux limits that…

Astrophysics · Physics 2007-05-23 I. Waddington

(abridged) We present multiwavelength observations for a large sample of microjansky radio sources detected in ultradeep 1.4GHz maps centered on the Hubble Deep Field-North (HDF-N) and the Hawaii Survey Fields SSA13 and SSA22. Our…

We present the results from two radio integrations at 8.4 GHz using the VLA. One of the fields, at 13h,+43d (SA13 field), has an rms noise level of 1.49 microJy and is the deepest radio image yet made. Thirty-four sources in a complete…

A sample of high-frequency peaker (HFP) candidates was formed from the AT20G catalog radio sources with spectral indices of the optically thick emission region $\alpha_{below}$ exceeding +0.5. A study of the spectral properties of the…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-12 Elena Majorova , Olga Zhelenkova

We have assembled an 8.4 GHz survey of bright, flat-spectrum (alpha > -0.5) radio sources with nearly uniform extragalactic (|b|>10 deg) coverage for sources brighter than S_{4.8 GHz} = 65 mJy. The catalog is assembled from existing…

Our sample of giant radio-source candidates, published in Paper I (Machalski et al. 2001), is updated and supplemented with further radio and optical data. In this paper we present: (i) newly detected host galaxies, their photometric…

Astrophysics · Physics 2009-11-11 J. Machalski , M. Jamrozy , S. Zola , D. Koziel

We investigate the nature of the faintest radio sources detected in 3 VLA surveys, to faint limits 8 microJy at 8.5 GHz. Using the Keck Low Resolution Imaging Spectrograph in BRI and the Near Infra Red Camera in K, we image 51 radio…

Astrophysics · Physics 2009-11-07 Nathan Roche , James Lowenthal , David Koo

We define a complete sample of thirty-three GHz-Peaked-Spectrum (GPS) radio sources based on their spectral properties. We present measurements of the radio spectra and polarization of the complete sample and a list of additional GPS…

Astrophysics · Physics 2016-08-30 C. Stanghellini , C. P. O'Dea , D. Dallacasa , S. A. Baum , R. Fanti , C. Fanti

At the faintest radio flux densities (S_1.4 < 10 mJy), conflicting results have arisen regarding whether there is a flattening of the average spectral index between a low radio frequency (325 or 610 MHz), and e.g. 1.4 GHz. We present a new…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Kate Randall , Andrew Hopkins , Ray Norris , Peter-Christian Zinn , Enno Middelberg , Minnie Mao , Rob Sharp
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