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Related papers: Compact steep-spectrum sources from the S4 sample

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Unified schemes of radio sources, which account for different types of radio AGN in terms of anisotropic radio and optical emission, together with different orientations of the ejection axis to the line of sight, have been invoked for many…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Neal Jackson , I. W. A. Browne

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 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…

I will review some of the developments in studies of the host galaxy properties of Compact Steep Spectrum (CSS) and GigaHertz-Peaked Spectrum (GPS) radio sources. In contrast to previous reviews structured around observational technique, I…

Astrophysics · Physics 2009-11-13 J. Holt

We present results of multifrequency polarimetric VLBA observations of 20 compact radio sources. The observations represent the northern and southern extensions of a large survey undertaken to identify Compact Symmetric Objects (CSOs)…

Astrophysics · Physics 2009-11-10 G. B. Taylor , A. B. Peck

We present results of EVN observations of eleven GHz-Peaked-Spectrum (GPS) radio sources at 2.3/8.4 GHz. These sources are from the classical ''bright'' GPS source samples with peak flux densities $>$ 0.2 Jy and spectral indices $\alpha <…

Astrophysics · Physics 2007-05-23 L. Xiang , D. Dallacasa , P. Cassaro , D. Jiang , C. Reynolds

(Abridged) We construct a catalog of radio sources detected by the GB6 (6 cm), FIRST and NVSS (20 cm), and WENSS (92 cm) radio surveys, and the SDSS optical survey. The 2.7 million entries in the publicly-available master catalog are…

Astrophysics · Physics 2009-01-16 Amy E. Kimball , Željko Ivezić

Compact Symmetric Objects (CSOs) are small (less than 1 kpc) radio sources which have symmetric double lobes or jets. The dominant theory for the small size of these objects is that they are young radio sources which could grow into larger…

Astrophysics of Galaxies · Physics 2010-11-11 S. E. Tremblay , G. B. Taylor , J. F. Helmboldt , C. D. Fassnacht , R. W. Romani

We present radio and optical analysis of a sample of Low Luminosity Compact (LLC) objects, selected from FIRST survey and observed with MERLIN at L-band and C-band. The main criterion used for selection was luminosity of the objects and…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-30 M. Kunert-Bajraszewska , A. Labiano , M. P. Gawronski

Compact, steep-spectrum radio sources are key tracers of exotic astrophysical objects such as pulsars and high-redshift radio galaxies. All-sky radio surveys at different frequencies, like the TIFR-GMRT Sky Survey (TGSS) and the NRAO VLA…

Astrophysics of Galaxies · Physics 2026-04-07 Rajat Shinde , Yogesh Maan , Apurba Bera

This paper deals with the spectral ageing study of a representative sample of compact symmetric objects (CSOs) and compact steep spectrum (CSS) sources. Observations reveal a distinctive high-frequency steepening of the radio spectra of…

Astrophysics · Physics 2009-11-07 Matteo Murgia

According to the currently accepted paradigm compact steep spectrum (CSS) sources are precursors of larger/older objects and gigahertz peaked spectrum (GPS) sources may be earlier stages of CSS sources. In this paper we confront this…

Astrophysics · Physics 2009-11-07 Andrzej Marecki , Ralph E. Spencer , Magdalena Kunert

The high-frequency integrated spectra of Compact Steep Spectrum (CSS) sources show breaks with a moderate spectral steepening well fitted by continuous injection synchrotron spectra. In lobe-dominated CSS sources the radiative ages deduced…

Astrophysics · Physics 2009-10-31 M. Murgia , C. Fanti , R. Fanti , L. Gregorini , U. Klein , K. -H. Mack , M. Vigotti

We present basic observational data on the 6C** sample. This is a new sample of radio sources drawn from the 151 MHz 6C survey, which was filtered with radio criteria chosen to optimize the chances of finding radio galaxies at z > 4. The…

Spectroscopy of high-redshift compact steep-spectrum (CSS) quasars shows a high incidence of Ly-alpha absorption close to the quasar redshift. Associated absorption systems like these are rare in other types of radio sources, with the…

Astrophysics · Physics 2007-05-23 Joanne C. Baker

The evolutionary stage of a powerful radio source originated by an AGN is related to its linear size. In this context, compact symmetric objects (CSOs), which are powerful and intrinsically small (< 1 kpc) radio sources with a convex…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-29 M. Orienti , G. Migliori , A. Siemiginowska , A. Celotti

It is currently accepted that intrinsically compact and bright radio sources characterized by a convex spectrum peaking at frequencies ranging from 100 MHz to a few GHz are young objects. Following the evolutionary models, these objects…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-02 M. Orienti , D. Dallacasa

We started a follow-up investigation of the Deep X-ray Radio Blazar Survey objects with declination >-10 deg. We undertook a survey with the EVN at 5GHz to make the first images of a complete sample of weak blazars, aiming at a comparison…

Astrophysics of Galaxies · Physics 2015-04-29 F. Mantovani , M. Bondi , K. -H. Mack , W. Alef , E. Ros , J. A. Zensus

We construct the first X-ray selected sample of broad line radio-loud AGN from the EMSS survey. In order to test unifying schemes for radio-loud objects, their spectral and statistical properties (both flat and steep spectrum objects) are…

Astrophysics · Physics 2009-11-06 Anna Wolter , Annalisa Celotti

Here we present a sample of sources with convex radio spectra peaking at frequencies above a few GHz. We call these radio sources High Frequency Peakers (HFPs). This sample extends to higher turnover frequencies than the samples of Compact…

Astrophysics · Physics 2016-08-30 Daniele Dallacasa , Carlo Stanghellini , Matteo Centonza , Roberto Fanti