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Related papers: Constraining the evolution of young radio-loud AGN

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Radio and X-ray emission of AGN appears to be correlated. The details of the underlying physical processes, however, are still not fully understood, i.e., to what extent is the X-ray and radio emission originating from the same relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-05 Jens Zuther , Sebastian Fischer , Andreas Eckart

Many of the powerful radio galaxies observed at high redshift are very small, presumably because they are very young. A simple model, which treats the radio source as a bubble expanding into a radially stratified medium, is capable of…

Astrophysics · Physics 2007-05-23 Mitchell C. Begelman

Multifrequency radio continuum observations (1.4-22 GHz) of a sample of reddened QSOs are presented. We find a high incidence (13/16) of radio spectral properties, such as low frequency turnovers, high frequency spectral breaks or steep…

High Energy Astrophysical Phenomena · Physics 2012-01-20 A. Georgakakis , M. Grossi , J. Afonso , A. M. Hopkins

Associated with one of the most important forms of active galactic nucleus (AGN) feedback, and showing a strong preference for giant elliptical host galaxies, radio AGN (L_1.4GHz > 10^24 W Hz^-1) are a key sub-class of the overall AGN…

Astrophysics of Galaxies · Physics 2016-06-22 Clive Tadhunter

The dependence of the turnover frequency on the linear size is presented for a sample of GPS and CSS radio sources derived from complete samples. The dependence of the luminosity of the emission at the peak frequency with the linear size…

Astrophysics of Galaxies · Physics 2016-04-20 Solai Jeyakumar

A recent multi-year Caltech-NRAO Stripe 82 Survey (CNSS) revealed a group of objects that appeared as new radio sources after $>$5--20 years of absence. They are transient phenomena with respect to the Faint Images of the Radio Sky at…

Aims: The knowledge of the properties of the youngest radio sources is very important in order to trace the earliest phase of the evolution of the radio emission. RXJ1459+3337, with its high turnover frequency (~25 GHz) provides a unique…

Astrophysics · Physics 2009-11-13 M. Orienti , D. Dallacasa

We present the results of a high-resolution, 5 GHz, Karl G. Jansky Very Large Array study of the nuclear radio emission in a representative subset of the Atlas3D survey of early-type galaxies (ETGs). We find that 51 +/- 4% of the ETGs in…

This paper presents the X-ray properties of a flux- and volume-limited complete sample of 16 Giga-Hertz Peaked Spectrum (GPS) galaxies. This study addresses three basic questions in our understanding of the nature and evolution of GPS…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Olof Tengstrand , M. Guainazzi , A. Siemiginowska , N. Fonseca Bonilla , A. Labiano , D. M. Worrall , P. Grandi , E. Piconcelli

We investigate the luminosity evolution of the host galaxies of radio-loud AGN through Hubble Space Telescope imaging of 72 BL Lac objects, including new STIS imaging of nine z > 0.6 BL Lacs. With their intrinsically low accretion rates and…

Astrophysics · Physics 2009-11-10 Matthew O'Dowd , C. Megan Urry

We model the evolution of active galactic nuclei by constructing their radio luminosity functions. We use a set of surveys of varying area and depth, namely the deep COSMOS survey of $1,916$ AGN sources, the wide shallow 3CRR, 7C and 6CE…

Astrophysics of Galaxies · Physics 2023-12-25 B. Šlaus , V. Smolcic , Ž. Ivezic , S. Fotopoulou , C. J. Willott , P. Pendo , C. Vignali , L. Chiappetti , M. Pierre

We used the Australia Telescope Compact Array (ATCA) to obtain 40 GHz and 95 GHz observations of a number of sources that were selected from the Australia Telescope Compact Array 20 GHz (AT20G) survey . The aim of the observations was to…

Astrophysics of Galaxies · Physics 2015-05-19 Paul J. Hancock , Elaine M. Sadler , Elizabeth K. Mahony , Roberto Ricci

We propose that Gigahertz Peak Spectrum (GPS) and Compact Steep Spectrum (CSS) radio sources are the signposts of relativistic jet feedback in evolving galaxies. Our simulations of relativistic jets interacting with a warm, inhomogeneous…

Giant radio sources, including galaxies and quasars (hereafter GRGs), are active galactic nuclei (AGN) hosting relativistic jets with source sizes exceeding the projected length of 0.7 Mpc. They are crucial to understanding the evolution of…

High Energy Astrophysical Phenomena · Physics 2025-07-08 Vaidehi S. Paliya , D. J. Saikia , Gabriele Bruni , Alberto Dominguez , C. S. Stalin

We have formed a complete sample of 26 low redshift (z < 0.3) giant radio galaxies (GRGs) from the WENSS survey, selected at flux densities above 1 Jy at 325 MHz. We present 10.5-GHz observations with the 100-m Effelsberg telescope of 18…

We have determined the central velocity dispersion and surface brightness profiles for a sample of powerful radio galaxies in the redshift range 0.06<z<0.31, which were selected on the basis of their young radio source. The optical hosts…

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

We study the morphology of the radio emission of giant radio galaxies (GRGs), a rare type of active galaxies, in order to find new clues for the reasons of their large size. Using radio images from two sky surveys at 1.4 GHz we quantified…

Astrophysics of Galaxies · Physics 2016-10-11 Elizabeth López Vázquez , Heinz Andernach

We study the uniformity of the distribution of compact flat-spectrum AGN on the sky and the evolution of their relativistic jets with cosmic epoch. A complete sample of compact extragalactic radio sources at 15 GHz was recently compiled to…

Astrophysics · Physics 2009-11-11 Tigran Arshakian , Eduardo Ros , Anton Zensus

The term 'active galactic nuclei' (AGN) subtends a huge variety of objects, classified on their properties at different wavelengths. Peaked sources (PS) represent a class of AGN at the first stage of evolution, characterised by a peaked…

Astrophysics of Galaxies · Physics 2024-09-11 A. Vietri , M. Berton , E. Järvelä , M. Kunert-Bajraszewska , S. Ciroi , I. Varglund , B. Dalla Barba , E. Sani , L. Crepaldi

We address the relation between star formation and AGN activity in a sample of 231 nearby ($0.0002<z<0.0358$) early type galaxies by carrying out a multi-wavelength study using archival observations in the UV, IR and radio. Our results…

Astrophysics of Galaxies · Physics 2016-03-09 Sravani Vaddi , Christopher P. ODea , Stefi A. Baum , Samantha Whitmore , Rabeea Ahmed , Katherine Pierce , Sara Leary
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