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Related papers: The evolution of extragalactic radio sources

200 papers

Extragalactic jets exhibit a wide range of propagation orientations relative to the host galaxy's principal axis. This study investigate the spatiotemporal evolution of jets as a function of their propagation direction within their triaxial…

Contribution of resolved and unresolved extragalactic point sources to the low-frequency sky spectrum is a potentially non-negligible part of the astrophysical foregrounds for cosmic dawn 21-cm experiments. The clustering of such point…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-01 Shikhar Mittal , Girish Kulkarni , Dominic Anstey , Eloy de Lera Acedo

The study of the broad-band emission of GHz-Peaked-Spectrum (GPS) radio galaxies is a powerful tool to investigate the physical processes taking place in the central, kpc-sized region of their active hosts, where the jets propagate and the…

We describe the pitfalls encountered in deducing from classical double radio source observables (luminosity, spectral index, redshift and linear size) the essential nature of how these objects evolve. We discuss the key role played by…

Astrophysics · Physics 2009-10-31 Katherine Blundell , Steve Rawlings , Chris Willott , Namir Kassim , Rick Perley

We present a new sample of Compact Steep Spectrum (CSS) sources with radio luminosity below 10^26 W/Hz at 1.4 GHz called the low luminosity compact (LLC) objects. The sources have been selected from FIRST survey and observed with MERLIN at…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 M. Kunert-Bajraszewska , M. P. Gawronski , A. Labiano , A. Siemiginowska

We describe a new estimate of the radio galaxy 1.4 GHz luminosity function and its evolution at intermediate redshifts (z~0.4). Photometric redshifts and color selection have been used to select Bj<23.5 early-type galaxies from the…

Astrophysics · Physics 2009-11-06 M. J. I. Brown , R. L. Webster , B. J. Boyle

We point out that the remarkable linearity of the ultra-steep radio spectra of high redshift radio galaxies reflects a previously reported general trend for powerful radio galaxies, according to which the spectral curvature is lesser for…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Gopal-Krishna , Mukul Mhaskey , A. Mangalam

Compact steep-spectrum (CSS) and peaked spectrum (PS) radio sources are compact, powerful radio sources. The multi-frequency observational properties and current theories are reviewed with emphasis on developments since the earlier review…

Astrophysics of Galaxies · Physics 2021-04-07 Christopher P. O'Dea , D. J. Saikia

A relativistic radio component, which moves in a direction close to the sky plane, will increase in flux density when it decelerates. This effect is the basis for the qualitative model for GPS galaxies we present in this paper, which can…

Astrophysics · Physics 2007-05-23 I. A. G. Snellen , R. T. Schilizzi , A. G. de Bruyn , G. K. Miley

We present an extensive analysis on the determination of the isotropic radio background. We consider six different radio maps, ranging from 22 MHz to 2.3 GHz and covering a large fraction of the sky. The large scale emission is modeled as a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Nicolao Fornengo , Roberto A. Lineros , Marco Regis , Marco Taoso

We address in this work the nature and evolution of the long-period compact star sources, which has recently added several unexpected members. The central hypothesis is that particle winds drive their evolution, being an important factor…

High Energy Astrophysical Phenomena · Physics 2024-02-13 J. E. Horvath , Lucas M. de Sá , Lívia S. Rocha , Gustavo Y. Chinen , Lucas G. Barão , Márcio G. B. de Avellar

Radio relics are diffuse synchrotron sources that illuminate shock waves in the intracluster medium. In recent years, radio telescopes have provided detailed observations about relics. Consequently, cosmological simulations of radio relics…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-02 Denis Wittor , Matthias Hoeft , Marcus Brüggen

We have used the available samples of Gigahertz Peaked Spectrum (GPS) galaxies to investigate their evolution properties in the framework of the ``youth'' scenario. Care was taken to properly allow for the different selection criteria used…

Astrophysics · Physics 2009-11-11 S. Tinti , G. De Zotti

We present an analysis of the spectral properties of the extragalactic radio sources in the nearly-complete VSA sample at 33GHz. Data from different surveys are used to study source spectra between 1.4 and 33GHz. We find that, in general,…

The number of observed giant radio sources (GRSs) has increased significantly in recent years, yet their formation mechanisms remain elusive. The discovery of giant radio galaxies within galaxy clusters has further intensified the ongoing…

Astrophysics of Galaxies · Physics 2025-05-14 Xiaodong Duan , Linhui Wu , Ruiyu Zhang , Jiawen Li

High-redshift radio-loud quasars are used to, among other things, test the predictions of cosmological models, set constraints on black hole growth in the early universe and understand galaxy evolution. Prior to this paper, 20 extragalactic…

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…

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

I briefly review our current knowledge of the cosmological evolution of radio sources, and show that the redshift distributions of new complete samples of radio sources confirm the existence of the high-redshift decline in comoving number…

Astrophysics · Physics 2007-05-23 James Dunlop

We extend the study of the radio emission in early-type galaxies (ETGs) in the nearby Universe (recession velocity <7,500 km/s) as seen by the 150 MHz Low-Frequency ARray (LOFAR) observations and extend the sample from giant ETGs to massive…

Astrophysics of Galaxies · Physics 2023-08-23 A. Capetti , M. Brienza