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Related papers: Extragalactic radio source evolution & unification…

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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,…

Astrophysics · Physics 2009-10-30 C A Jackson , J V Wall

We present detailed predictions of the contributions of the various source populations to the counts at frequencies of tens of GHz. New evolutionary models are worked out for flat-spectrum radio quasars, BL Lac objects, and steep-spectrum…

Observations of blazar jets are shrouded in relativistic effects, thus hindering our understanding of their intrinsic properties and dominant physical processes responsible for their generation, evolution,radiation and particle emission. In…

High Energy Astrophysical Phenomena · Physics 2015-06-16 I. Liodakis , V. Pavlidou

We discuss the preliminary results of an extensive effort to address the fundamental, and yet un-answered, question that can be trivialized as: ``are there more blue or red blazars?''. This problematic is tightly connected with the much…

Astrophysics · Physics 2007-05-23 G. Fossati

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…

Astrophysics · Physics 2007-05-23 C A Jackson , J V Wall

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

The up-turn in Euclidean normalised source counts below 1mJy at 1.4GHz is well established in many deep radio surveys. There are strong reasons, observationally and theoretically, to believe that this up-turn is due to strong evolution of…

Astrophysics · Physics 2007-05-23 Nick Seymour , Ian McHardy , Katherine Gunn , Derek Moss

The goal of this article is to summarize the current state of play in the field of radio pulsar statistics. Simply put, from the observed sample of objects from a variety of surveys with different telescopes, we wish to infer the properties…

Astrophysics of Galaxies · Physics 2015-05-19 D. R. Lorimer

CMB surveys provide, for free, blindly selected samples of extragalactic radio sources at much higher frequencies than traditional radio surveys. Next-generation, ground-based CMB experiments with arcmin resolution at mm wavelengths will…

Surveys at mm wavelengths emphasize rare classes of extragalactic radio sources characterized by spectra keeping flat or inverted up to high frequencies (such as blazars, GPS sources, advection dominated sources, or even gamma-ray burst…

We present the population data as predicted by our space density analysis at the SUMSS frequency of 843 MHz. This data demonstrates the potential of the SUMSS survey to trace in detail the change-over in radio source populations from `radio…

Astrophysics · Physics 2007-05-23 C A Jackson , J V Wall

The change in the slope of the radio source counts suggests the emergence of a new population of radio galaxies at mJy and sub-mJy levels. Our understanding of such faint radio sources has advanced over the last decade through increasingly…

Astrophysics · Physics 2007-05-23 L. Gregorini , I. Prandoni

We present a new evolutionary model that describes the population properties of radio sources at frequencies <5 GHz, thus complementing the De Zotti et al. (2005) model, holding at higher frequencies. We find that simple analytic luminosity…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Marcella Massardi , Anna Bonaldi , Mattia Negrello , Sara Ricciardi , Alvise Raccanelli , Gianfranco De Zotti

Blazars represent dominant population of the extragalactic $\gamma$-ray sources in the Universe. These sources exhibit some characteristic properties like strong and non-thermal continuum emission over the entire electromagnetic spectrum…

High Energy Astrophysical Phenomena · Physics 2020-10-07 K. K. Singh , P. J. Meintjes

The evolution of symmetric extragalactic radio sources can be characterized by four distinct growth stages of the radio luminosity versus size of the source. The interaction of the jet with the ambient medium results in the formation and…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-09 Tao An , Willem A. Baan

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

We discuss the contribution of the blazar population to the extragalactic background radiation across the electromagnetic (e.m.) spectrum with particular reference to the microwave, hard-X-ray and gamma-ray bands. Our estimates are based on…

Astrophysics · Physics 2007-05-23 P. Giommi , S. Colafrancesco

We study constraints on the population of neutrino emitting blazars imposed by the absence of doublets in astrophysical muon neutrino signal and z>0.3 redshift of nearest identified neutrino-emitting blazar (an order of magnitude further…

High Energy Astrophysical Phenomena · Physics 2020-10-28 A. Neronov , D. V. Semikoz

Aims. The mass discrepancy between the observed population of double neutron star binaries by radio pulsar observations and gravitational-wave observation requires an explanation. Methods. Binary population synthesis calculations are…

Solar and Stellar Astrophysics · Physics 2020-07-22 Matthias U. Kruckow

The 2002 status of unification models for extragalactic radio sources is examined, with particular emphasis on the dust properties of these objects.

Astrophysics · Physics 2009-11-07 P. D. Barthel , I. M. van Bemmel
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