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In this paper the cosmic evolution of the space density of Fanaroff & Riley Class I (FRI) radio sources is investigated out to z ~ 1, in order to understand the origin of the differences between these and the more powerful FRIIs. High…

天体物理学 · 物理学 2009-11-13 E. E. Rigby , P. N. Best , I. A. G. Snellen

The Combined NVSS-FIRST Galaxy (CoNFIG) survey was defined by selecting all sources with S_1.4GHz > 1.3Jy from the NRAO VLA Sky Survey (NVSS) in the north field of the Faint Images of the Radio Sky at Twenty-cm (FIRST) survey. We carried…

天体物理学 · 物理学 2009-04-14 Melanie A. Gendre , Jasper V. Wall

The CoNFIG (Combined NVSS-FIRST Galaxies) sample is a new sample of 274 bright radio sources at 1.4 GHz. It was defined by selecting all sources with S_1.4GHz > 1.3 Jy from the NRAO-VLA Sky Survey (NVSS) in the North field of the Faint…

天体物理学 · 物理学 2009-11-13 M. A. Gendre , J. V. Wall

This paper focuses on a comparison of the space densities of FRI and FRII sources at different epochs, with a particular focus on FRI sources. First, we present the concluding steps in constructing the Combined NVSS-FIRST Galaxy catalogue…

宇宙学与河外天体物理 · 物理学 2015-05-18 Melanie A. Gendre , P. N. Best , J. V. Wall

We show that a dual-population unification scheme provides a successful paradigm with which to describe the evolution and beaming of all bright extragalactic radio sources. The paradigm consists of two intrinsic radio-source populations,…

天体物理学 · 物理学 2009-10-30 C A Jackson , J V Wall

Current wide-area radio surveys are dominated by active galactic nuclei, yet many of these sources have no identified optical counterparts. Here we investigate whether one can constrain the nature and properties of these sources, using…

高能天体物理现象 · 物理学 2015-06-23 Sjoert van Velzen , Heino Falcke , Elmar Koerding

Extragalactic radio sources are a unique cosmological probe in that they trace large-scale structure on scales inaccessible to other wavelengths. However as radio survey data is inherently 2D, the redshift distribution, N(z), is necessary…

天体物理学 · 物理学 2007-05-23 C A Jackson , J V Wall

We present an analytical model for the cosmological evolution of the FRII source population. Based on an earlier model for the intrinsic radio luminosity - linear size evolution of these objects, we construct theoretical source samples. The…

天体物理学 · 物理学 2009-10-30 Christian R. Kaiser , Paul Alexander

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…

天体物理学 · 物理学 2009-10-31 E. A. Richards

We present deep VLA observations of the polarization of radio sources in the GOODS-N field at 1.4 GHz at resolutions of 1.6" and 10". At 1.6", we find that the peak flux cumulative number count distribution is N($>$p) $\sim$ 45 *…

星系天体物理 · 物理学 2014-03-31 Lawrence Rudnick , Frazer Owen

The dynamical evolution and radiative properties of luminous radio galaxies and quasars of the FRII type, are well understood. As a result, through the use of detailed modeling of the observed radio emission of such sources, one can…

星系天体物理 · 物理学 2021-12-08 Anna Wojtowicz , Lukasz Stawarz , Jerzy Machalski , Luisa Ostorero

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…

天体物理学 · 物理学 2009-10-31 E. A. Richards

We describe deep, new, wide-field radio continuum observations of the Great Observatories Origins Deep Survey -- North (GOODS-N) field. The resulting map has a synthesized beamsize of ~1.7" and an r.m.s. noise level of ~3.9uJy/bm near its…

宇宙学与河外天体物理 · 物理学 2015-05-18 Glenn E. Morrison , Frazer N. Owen , Mark Dickinson , Rob J. Ivison , Edo Ibar

Radio-loud active galactic nuclei (RLAGN) play an important role in the evolution of galaxies through the effects on their environment. The two major morphological classes are core-bright (FRI) and edge-bright (FRII) sources. With the…

We present the results from the analysis of 26 extragalactic radio sources of type FRII which were observed with the VLA at 5 GHz and around the 1.4 GHz band. The sources were selected to have redshifts in the range $ 0.3<z<1.3$, radio…

天体物理学 · 物理学 2017-08-23 J. A. Goodlet , C. R. Kaiser

We have formed a new sample which consists of extended extragalactic radio sources without obvious active galactic nuclei (AGN) in them. Most of these sources appear to be dead double radio sources. These sources with steep spectra ($\alpha…

星系天体物理 · 物理学 2011-02-11 K. S. Dwarakanath , Ruta Kale

We present an updated repository of sub-mJy extragalactic radio source counts between $150$ MHz and $10$ GHz, incorporating recent advances in radio surveys and observational techniques. By compiling and refining previous datasets, we…

星系天体物理 · 物理学 2025-04-02 Vincenzo Galluzzi , Meriem Behiri , Marika Giulietti , Andrea Lapi

We positionally match the 6 cm GB6, 20 cm FIRST and NVSS, and 92 cm WENSS radio catalogs and find 16,500 matches in ~3,000 deg2 of sky. Using this unified radio database, we construct radio "color-magnitude-morphology" diagrams and find…

Published data from long-term observations of a strip of sky at declination +5 degrees carried out at 7.6 cm on the RATAN-600 radio telescope are used to estimate some statistical properties of radio sources. Limits on the sensitivity of…

宇宙学与河外天体物理 · 物理学 2012-05-24 Yu. N. Parijskij , N. S. Soboleva , A. V. Temirova , N. N. Bursov , O. P. Zhelenkova

The advent of next-generation telescope facilities brings with it an unprecedented amount of data, and the demand for effective tools to process and classify this information has become increasingly important. This work proposes a novel…

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