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Related papers: The structure function of variable 1.4 GHz radio s…

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We present a 74 MHz survey of a 165 square degree region located near the north galactic pole. This survey has an unprecedented combination of both resolution (25'' FWHM) and sensitivity (RMS noise as low as 24 mJy/beam). We detect 949…

Astrophysics · Physics 2009-11-10 A. S. Cohen , H. J. A. Rottgering , M. J. Jarvis , N. E. Kassim , T. J. W. Lazio

We present an alternative estimate of the unresolved point source contribution to the WMAP temperature power spectrum based on current knowledge of sources from radio surveys in the 1.4-90 GHz range. We implement a stochastic extrapolation…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Loris P. L. Colombo , Elena Pierpaoli

Characterising spectral variability of radio sources is a technique that offers the ability to determine the astrophysics of the intervening media, source structure, emission and absorption processes. We present broadband (0.072--10 GHz)…

Astrophysics of Galaxies · Physics 2022-04-06 K. Ross , N. Hurley-Walker , N. Seymour , J. R. Callingham , T. J. Galvin , M. Johnston-Hollitt

We present deep radio maps from the Very Large Array (VLA) for 16 sources detected in a sub-millimeter (submm) survey of the distant Universe. Our deep VLA 1.4-GHz maps allow us to identify radio counterparts or place stringent limits…

Astrophysics · Physics 2009-10-31 Ian Smail , R. J. Ivison , F. N. Owen , A. W. Blain , J. -P. Kneib

We review the statistical properties of the main populations of radio sources, as emerging from radio and millimeter sky surveys. Recent determinations of local luminosity functions are presented and compared with earlier estimates still in…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Gianfranco De Zotti , Marcella Massardi , Mattia Negrello , Jasper Wall

In order to trace the instantaneous star formation rate at high redshift, and hence help understanding the relation between the different emission mechanisms related to star formation, we combine the recent 4 Ms Chandra X-ray data and the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 S. Vattakunnel , P. Tozzi , F. Matteucci , P. Padovani , N. Miller , M. Bonzini , V. Mainieri , M. Paolillo , L. Vincoletto , W. N. Brandt , B. Luo , K. I. Kellermann , Y. Q. Xue

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 present the first results from a pilot study to search for distant radio galaxies in the southern hemisphere (delta < -32). Within a 360 deg^2 region of sky, we define a sample of 76 ultra-steep spectrum (USS) radio sources from the 843…

We search for variable sources, using the data of the surveys conducted on the RATAN-600 radio telescope in 1980-1994 at 3.94 GHz. To test the radio sources of the RCR (RATAN Cold Refined) catalog for variability, we estimated the long-term…

Astrophysics of Galaxies · Physics 2014-09-15 E. K. Majorova , O. P. Zelenkova

Ultra Steep Spectrum (USS) radio sources are one of the efficient tracers of High Redshift Radio Galaxies (HzRGs). To search for HzRGs candidates, we investigate properties of a large sample of faint USS sources derived from our deep 325…

We present an optical spectroscopic survey of 24 micron and 1.4 GHz sources, detected in the Spitzer Extragalactic First Look Survey (FLS), using the multi-fiber spectrograph, Hydra, on the WIYN telescope. We have obtained spectra for 772…

Astrophysics · Physics 2011-02-11 F. R. Marleau , D. Fadda , P. N. Appleton , A. Noriega-Crespo , M. Im , D. Clancy

Surveys for transient and variable phenomena can be confounded by the presence of extrinsic variability such as refractive interstellar scintillation (RISS). We have developed an all-sky model for RISS which can predict variability on a…

Astrophysics of Galaxies · Physics 2019-07-26 P. J. Hancock , E. G. Charlton , J-P. Macquart , N. Hurley-Walker

In our first paper we described three regions of the 9C survey of radio sources with the Ryle telescope at 15.2 GHz, constituting a total area of 520 deg^2 to a completeness limit of approximately 25 mJy. Here we report on a series of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 E. M. Waldram , G. G. Pooley , M. L. Davies , K. J. B. Grainge , P. F. Scott

Cheung identified a sample of 100 candidate X-shaped radio galaxies using the NRAO FIRST survey; these are small-axial-ratio extended radio sources with off-axis emission. Here we present radio images of 52 of these sources that have been…

Astrophysics of Galaxies · Physics 2015-09-16 David H. Roberts , Jake P. Cohen , Jing Lu , Lakshmi Saripalli , Ravi Subrahmanyan

The Australia Telescope Compact Array (ATCA) has been used to survey at 1.4GHz, a small region (< 3 sq deg) overlapping with the 2dF Galaxy Redshift Survey (Colless et al. 2001, MNRAS, 328, 1039). We surveyed with a varying radio…

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…

Astrophysics · Physics 2009-10-31 F. E. Bauer , J. J. Condon , T. X. Thuan , J. J. Broderick

We report on the discovery of one of the most extreme cases of high-frequency radio variability ever measured in active galactic nuclei (AGN), observed on timescales of days and exhibiting variability amplitudes of three to four orders of…

The centimeter-wave luminosity of local radio galaxies correlates well with their star formation rate. We extend this correlation to surveys of high-redshift radio sources to estimate the global star formation history. The star formation…

Astrophysics · Physics 2010-04-01 D. B. Haarsma , R. B. Partridge , R. A. Windhorst , E. A. Richards

This paper presents 1.4-GHz radio continuum observations of 15 very extended radio galaxies. These sources are so large that most interferometers lose partly their structure and total flux density. Therefore, single-dish detections are…

Astrophysics of Galaxies · Physics 2016-04-19 M. Wezgowiec , M. Jamrozy , K. -H. Mack

As a service to the community, we have compiled radio frequency spectra from the literature for all sources within the VLA Low Frequency Sky Survey (VLSS) that are brighter than 15 Jy at 74 MHz. Over 160 references were used to maximize the…

Astrophysics · Physics 2009-11-13 J. F. Helmboldt , N. E. Kassim , A. S. Cohen , W. M. Lane , T. J. Lazio