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Related papers: The evolution of extragalactic radio sources

200 papers

The shape of low-frequency radio continuum spectra of normal galaxies is not well understood, the key question being the role of physical processes such as thermal absorption in shaping them. In this work we take advantage of the LOFAR…

Many of the compact extragalactic radio sources that are used as fiducial points to define the celestial reference frame are known to have proper motions detectable with long-term geodetic/astrometric Very Long Baseline Interferometry…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-16 A. Moór , S. Frey , S. B. Lambert , O. Titov , J. Bakos

We investigate different scenarios for the origin of the extragalactic radio background. The surface brightness of the background, as reported by the ARCADE 2 collaboration, is several times higher than that which would result from…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 J. Singal , L. Stawarz , A. Lawrence , V. Petrosian

The extended lobes of radio galaxies are examined as sources of X-ray and gamma-ray emission via inverse Compton scattering of 3K background photons. The Compton spectra of two exemplary examples, Fornax A and Centaurus A, are estimated…

Astrophysics · Physics 2009-06-23 C. C. Cheung

This article outlines a method to interpret the extragalactic background light in terms of the large-scale, average properties of galaxies, including the comoving densities of stars and interstellar gas, metals, and dust. These quantities…

Astrophysics · Physics 2007-05-23 S. Michael Fall

In this paper we analyse whether `giant' radio galaxies (GRGs) differ from `normal'-size galaxies (NSGs) except for the linear extent of their radio structure. We compare a number of properties of GRGs with the corresponding properties of…

Astrophysics · Physics 2009-11-11 J. Machalski , M. Jamrozy

A wide range of phenomena, from explosive transients to active galactic nuclei, exhibit variability at radio wavelengths on timescales of a few years. Characterizing the rate and scale of variability in the radio sky can provide keen…

Astrophysics of Galaxies · Physics 2026-05-21 Yjan A. Gordon , Peter S. Ferguson , Michael N. Martinez , Eric J. Hooper

Quantifying how the baryonic matter traces the underlying dark matter distribution is key to both understanding galaxy formation and our ability to constrain the cosmological model. Using the cross-correlation function of radio and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 S. N. Lindsay , M. J. Jarvis , K. McAlpine

The electron-cyclotron maser instability is widespread in the Universe, producing, e.g., radio emission of the magnetized planets and cool substellar objects. Diagnosing the parameters of astrophysical radio sources requires comprehensive…

Solar and Stellar Astrophysics · Physics 2015-06-04 A. A. Kuznetsov , V. G. Vlasov

Compact Symmetric Objects (CSOs) are considered the young counterparts of large doubles according to advance speeds measured or inferred from spectral ageing. Here we present a simple power law model for the CSO/FRII evolution based on the…

Astrophysics · Physics 2007-05-23 M. Perucho , J. M. Marti

{Early-type galaxies host low-luminosity active galactic nuclei, traced by radio emission spanning parsec- to kiloparsec scales.} {We investigate the Eddington-scaled radio luminosity distribution of 117 nearby early-type galaxies to test…

Astrophysics of Galaxies · Physics 2026-03-25 A. Wójtowicz , N. Werner , Ł. Stawarz , C. C. Cheung

We present a new sample of strong gravitational lens systems where both the foreground lenses and background sources are early-type galaxies. Using imaging from HST/ACS and Keck/NIRC2, we model the surface brightness distributions and show…

We have acquired radio continuum data between 70\,MHz and 48\,GHz for a sample of 19 southern starburst galaxies at moderate redshifts ($0.067 < z < 0.227$) with the aim of separating synchrotron and free-free emission components. Using a…

Spectral measurements of the 21 cm monopole background have the promise of revealing the bulk energetic properties and ionization state of our universe from z ~ 6-30. Synchrotron foregrounds are orders of magnitude larger than the…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-08 Eric R. Switzer , Adrian Liu

Global VLBI observations at 5 GHz have been performed to study the source morphology in 10 compact steep-spectrum (CSS) sources selected from the Peacock & Wall catalogue with the aim of finding asymmetric structures produced by the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 D. Dallacasa , M. Orienti , C. Fanti , R. Fanti , C. Stanghellini

The synchrotron emission observed from many astrophysical objects is commonly modelled to arise from relativistic electrons in an emission region occupied by a spatially homogeneous, but tangled magnetic field. However, we know that…

Astrophysics · Physics 2009-11-10 Christian R. Kaiser

Both radiative and mechanical feedback from Active Galactic Nuclei have been found to be important for the evolution of elliptical galaxies. We compute how a shock may be driven from a central black hole into the gaseous envelope of an…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 Y. -F. Jiang , L. Ciotti , J. P. Ostriker , A. Spitkovsky

Many X-ray observations of GigaHertz Peaked Spectrum and Compact Steep Spectrum sources have been made with Chandra X-ray Observatory and XMM-Newton Observatory over the last few years. The X-ray spectra contribute the important information…

High Energy Astrophysical Phenomena · Physics 2009-11-13 Aneta Siemiginowska

This paper investigates whether nonlinear gravitational instability can account for the clustering of galaxies on large and small scales, and for the evolution of clustering with epoch. No CDM-like spectrum is consistent with the shape of…

Astrophysics · Physics 2015-06-24 J. A. Peacock

We present deep spectroscopic data for a 24-object subsample of our full 41-object z~0.5 radio galaxy sample in order to investigate the evolution of the Fundamental Plane of radio galaxies. We find that the low-luminosity, FRI-type, radio…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Peter D. Herbert , Matt J. Jarvis , Chris J. Willott , Ross J. McLure , Ewan Mitchell , Steve Rawlings , Gary J. Hill , James S. Dunlop