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Starting from the Cambridge Catalogues of radio sources, we have created a sample of 401 FRII radio sources that have counterparts in the main galaxy sample of the 7th Data release of the SDSS and analyse their radio and optical properties.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Dorota Kozieł-Wierzbowska , Grażyna Stasińska

We are constructing the broadband SED catalog of the MOJAVE sample from the radio to the gamma-ray band using MOJAVE, Swift UVOT/XRT/BAT, and Fermi/LAT data, in order to understand the emission mechanism of extragalactic outflows and to…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-25 C. S. Chang , E. Ros , M. Kadler , M. F. Aller , H. D. Aller , E. Angelakis , L. Fuhrmann , I. Nestoras , H. Ungerechts

We propose a machine-learning-based technique to determine the number density of radio sources as a function of their flux density, for use in next-generation radio surveys. The method uses a convolutional neural network trained on…

Instrumentation and Methods for Astrophysics · Physics 2024-01-17 Elisa Todarello , Andre Scaffidi , Marco Regis , Marco Taoso

A significant fraction of extended radio sources presents a peculiar X-shaped radio morphology: in addition to the classical double lobed structure, radio emission is also observed along a second axis of simmetry in the form of diffuse…

Astrophysics of Galaxies · Physics 2017-10-11 P. Rossi , G. Bodo , A. Capetti , S. Massaglia

In previous papers we have discussed high-resolution observations of a large sample of powerful radio galaxies with z<0.3. Jets are detected in up to 80 per cent of the sample, and radio cores in nearly all the objects; in addition, we are…

Astrophysics · Physics 2009-10-30 M. J. Hardcastle , P. Alexander , G. G. Pooley , J. M. Riley

Physical parameters of AGN jets observed with Very Long Baseline Interferometry (VLBI) are usually inferred from the core shift measurements or flux and size measured at a peak frequency of the synchrotron spectrum. Both are preceded by…

Astrophysics of Galaxies · Physics 2019-08-05 Ilya N. Pashchenko , Alexander V. Plavin

Despite significant strides made towards understanding accretion, outflow, and emission processes in the Galactic Center supermassive black hole Sagittarius A*, the presence of jets has neither been rejected nor proven. We investigate here…

Astrophysics · Physics 2008-11-26 Sera Markoff , Geoffrey C. Bower , Heino Falcke

We present hand-curated size measurements for a sample of 2,002 multiple-component radio AGNs in the Radio sources associated with Optical Galaxies and having Unresolved or Extended morphologies I (ROGUE I) catalog. The sources span total…

The radio properties of 11 obscured `radio-intermediate' quasars at redshifts z>~2 have been investigated using the European Very-Long-Baseline-Interferometry Network (EVN) at 1.66 GHz. A sensitivity of ~25 micro Jy per 14x17 mas2 beam was…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 H. -R. Kloeckner , A. Martinez-Sansigre , S. Rawlings , M. A. Garrett

An increasing number of observations and simulations suggests that low-power (<10$^{44}$ erg s$^{-1}$) jets may be a significant channel of feedback produced by active galactic nuclei (AGN), but little is known about their actual effect on…

The relative positions of the high and low surface brightness regions of radio-loud active galaxies in the 3CR sample were found by Fanaroff and Riley to be correlated with their luminosity. We revisit this canonical relationship with a…

We present a comparison of the optical and radio properties of radio sources inside and outside the cores of rich clusters from combined samples of more than 380 radio sources. We also examine the nature of FR I and FR II host galaxies, and…

Astrophysics · Physics 2009-10-31 M. J. Ledlow , F. N. Owen , J. A. Eilek

The significance of tidal interactions in the evolution of the faint radio population (sub-mJy) is studied using a deep and homogeneous radio survey (1.4 GHz), covering an area of 3.14 deg$^2$ and complete to a flux density of 0.4 mJy.…

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

The radio properties of hard (2-8keV) X-ray selected sources are explored by combining a single 50ks XMM-Newton pointing with the ultra-deep and homogeneous Phoenix radio (1.4GHz) survey (Hopkins et al. 2003). A total of 43 sources are…

Astrophysics · Physics 2009-11-10 A. Georgakakis , A. M. Hopkins , J. Afonso , M. Sullivan , B. Mobasher , L. E. Cram

We explore radio and spectroscopic properties of a sample of 14 miniature radio galaxies, i.e. early-type core galaxies hosting radio-loud AGN of extremely low radio power, 10^(27-29) erg s^(-1) Hz^(-1) at 1.4 GHz. Miniature radio galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Ranieri D. Baldi , Alessandro Capetti

Radio continuum surveys can detect galaxies over a very wide range in redshift, making them powerful tools for studying the distant universe. Until recently, though, identifying the optical counterparts of faint radio sources and measuring…

Astrophysics · Physics 2007-05-23 Elaine M. Sadler , Carole A. Jackson , Russell D. Cannon

We select a sample of radio galaxies at high redshifts (z>~1) in the COSMOS field, by cross-matching optical/infrared images with the FIRST radio data. The aim of this study is to explore the high-z radio-loud (RL) AGN population at much…

Astrophysics of Galaxies · Physics 2014-09-05 Ranieri D. Baldi , Alessandro Capetti , Marco Chiaberge , Annalisa Celotti

Fast Radio Bursts (FRBs) are energetic, short, bright transients that occur frequently over the entire radio sky. The observational challenges following from their fleeting, generally one-off nature have prevented identification of the…

High Energy Astrophysical Phenomena · Physics 2021-07-14 D. W. Gardenier , J. van Leeuwen

We present an analysis of deep mid- to far-infrared (MFIR) Spitzer photometric observations of the southern 2Jy sample of powerful radio sources (0.05 < z < 0.7), conducting a statistical investigation of the links between radio jet, AGN,…

Astrophysics · Physics 2011-02-11 D. Dicken , C. Tadhunter , D. Axon , R. Morganti , K. J. Inskip , J. Holt , R. Gonzalez Delgado , B. Groves

We studied bent radio sources within X-ray galaxy groups in the COSMOS and XMM-LSS fields, using radio data from the MeerKAT International GHz Tiered Extragalactic Explorations data release 1 (MIGHTEE-DR1) at 1.2-1.3 GHz (angular…