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

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We have conducted a deep radio survey with the Very Large Array at 1.4 GHz of a region containing the Hubble Deep Field. This survey overlaps previous observations at 8.5 GHz allowing us to investigate the radio spectral properties of…

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

A new sample of candidate Compact Steep Spectrum (CSS) sources that are much weaker than the CSS source prototypes has been selected from the VLA FIRST catalogue. MERLIN `snapshot' observations of the sources at 5 GHz indicate that six of…

We measure the angular power spectrum of radio galaxies in the NRAO VLA Sky Survey (NVSS) using two independent methods: direct spherical harmonic analysis and maximum likelihood estimation. The results are consistent and can be understood…

Astrophysics · Physics 2009-11-10 Chris Blake , Pedro G. Ferreira , Julian Borrill

In this paper we present the results of an optical and near infrared identification of 514 radio sources from the FIRST survey (Faint Images of the Radio Sky Survey at Twenty centimeters) with a flux-density limit of 1 mJy in the NOAO…

Astrophysics · Physics 2009-11-13 K. EL Bouchefry , C. M. Cress

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…

In the present paper we study the radio sources in the NRAO VLA SKY Survey (NVSS) analysing its power spectrum and galaxy distribution. There is a discrepancy between the theoretical models in the literature and the data at large scales. A…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-03 A. Marcos-Caballero , P. Vielva , E. Martinez-Gonzalez , F. Finelli , A. Gruppuso , F. Schiavon

The spectra of fast radio bursts (FRBs) encode valuable information about the source's local environment, underlying emission mechanism(s), and the intervening media along the line of sight. We present results from a long-term…

High Energy Astrophysical Phenomena · Physics 2021-01-06 Aaron B. Pearlman , Walid A. Majid , Thomas A. Prince , Kenzie Nimmo , Jason W. T. Hessels , Charles J. Naudet , Jonathon Kocz

We have used VLBA fringe visibility data obtained at 15 GHz to examine the compact structure in 250 extragalactic radio sources. For 171 sources in our sample, more than half of the total flux density seen by the VLBA remains unresolved on…

In this study we define a new sample of distant powerful radio galaxies in order to study their host-galaxy properties and provide targets for future observations of HI absorption with new radio telescopes and to understand the fuelling and…

Astrophysics of Galaxies · Physics 2019-09-25 Takalani Marubini , Matt J. Jarvis , Stephen Fine , Tom Mauch , Kim McAlpine , Matthew Prescott

The results of the analysis of 205 brightest sources ( $S>15$ mJy), which were found in the sky survey at the declination of the pulsar in the Crab Nebula, are presented. The survey was conducted at a frequency of 4.7~GHz using a three-beam…

High Energy Astrophysical Phenomena · Physics 2024-11-27 A. A. Kudryashova , N. N. Bursov , S. A. Trushkin

We report the results of multifrequency-VLBI observations of GHz-Peaked-Spectrum (GPS) radio sources. The VLBI structure and component spectra of some GPS sources are presented. Our VLBI results show that about 80% of the GPS galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-20 X. Liu , H. -G Song , L. Cui

We present radio observations of 19 candidate compact steep-spectrum (CSS) objects selected from a well-defined, complete sample of 52 B2 radio sources of intermediate strength. These observations were made with the VLA A-array at 4.835…

Astrophysics · Physics 2009-11-07 D. J. Saikia , P. Thomasson , R. E. Spencer , F. Mantovani , C. J. Salter , S. Jeyakumar

We present three new Chandra X-ray epochs along with new ground-based optical-UV observations as the third installment in a time-series analysis of four high-redshift ($z\sim4.1-4.4$) radio-quiet quasars (RQQs). In total, we present nine…

Radio observations offer a dust-independent probe of star formation and active galactic nucleus (AGN) activity, but sufficiently deep data are required to access the crossover luminosity between these processes at high redshift ($z>4.5$).…

We have started a search for High Redshift Radio Galaxies (HZRGs) in an area covering 7 sr by selecting a sample of Ultra Steep Spectrum (USS) sources with a low flux density cut-off S(1400 MHz) > 10 mJy and a steep spectral index cut-off…

Astrophysics · Physics 2016-01-27 Carlos De Breuck , Wil van Breugel , Huub Rottgering , George Miley

We describe a survey in the ELAIS N2 region with the VLA at 43.4 GHz, carried out with 1627 independent snapshot observations in D-configuration and covering about 0.5 square degrees. One certain source is detected, a previously-catalogued…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Jasper Wall , Rick Perley , Robert Laing , Sean Stotyn , Angela Taylor , Joe Silk

The 4.9 GHz Micro-Arcsecond Scintillation-Induced Variability (MASIV) Survey detected a drop in Interstellar Scintillation (ISS) for sources at redshifts z > 2, indicating an apparent increase in angular diameter or a decrease in flux…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-09 J. Y Koay , J. -P. Macquart , B. J. Rickett , H. E. Bignall , J. E. J. Lovell , C. Reynolds , D. L. Jauncey , T. Pursimo , L. Kedziora-Chudczer , R. Ojha

The incidence of young but fading radio sources provides important information on the life cycle of radio emission in radio-loud active galactic nuclei. Despite its importance for constraining the models of radio source evolution, there are…

Astrophysics of Galaxies · Physics 2023-05-03 M. Orienti , M. Murgia , D. Dallacasa , G. Migliori , F. D'Ammando

The results of an optical and infrared investigation of a complete sub-sample of the Leiden-Berkeley Deep Survey (flux > 1 mJy at 1.4 GHz) are presented. Optical counterparts have been identified for 69 of the 73 sources in the two Hercules…

Astrophysics · Physics 2009-10-31 Ian Waddington
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