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

200 papers

We have analysed VSOP (VLBI Space Observatory Programme) data at 5 GHz and ground-based VLBI (Very Long Baseline Interferometry) data at 15 GHz for the GHz-Peaked Spectrum (GPS) radio galaxy 2021+614. Its morphology is consistent with it…

Deep combination radio observations at 1.4GHz with the VLA and MERLIN have imaged a region 10 arcminutes square surrounding the Hubble Deep Field North (HDF-N). Initial studies of the weak radio source population have shown that the…

Astrophysics · Physics 2007-05-23 T. W. B. Muxlow , R. J. Beswick , H. Thrall , A. M. S Richards , S. T. Garrington , A. Pedlar

We study the Extended Chandra Deep Field South (E-CDFS) Very Large Array sample, which reaches a flux density limit at 1.4 GHz of 32.5 microJy at the field centre and redshift ~ 4, and covers ~ 0.3 deg^2. Number counts are presented for the…

Astrophysics of Galaxies · Physics 2015-08-06 P. Padovani , M. Bonzini , K. I. Kellermann , N. Miller , V. Mainieri , P. Tozzi

The polarisation properties of the intrinsically small (< 20 kpc) radio sources are briefly discussed. At centimetric and decimetric wavelengths, substantial polarised emission is often detected in quasars and, at a lower level, in radio…

Astrophysics · Physics 2007-05-23 D. Dallacasa

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

We are currently exploiting the deep radio/optical/IR information available for the extra-galactic component of the Spitzer First Look Survey (FLS) to investigate the physical properties of faint radio-selected AGNs, with the aim of…

Cosmology and Nongalactic Astrophysics · Physics 2010-08-31 I. Prandoni , R. Morganti , A. Mignano

Abridged. We present high-quality optical spectra for 12 powerful radio sources at low and intermediate redshifts (z < 0.7) that show evidence for a substantial UV excess. These data were taken using the WHT and VLT to determine the…

We investigate faint radio emission from low- to high-luminosity Active Galactic Nuclei (AGN) selected from the Sloan Digital Sky Survey (SDSS). Their radio properties are inferred by co-adding large ensembles of radio image cut-outs from…

Astrophysics · Physics 2008-11-26 W. H. de Vries , J. A. Hodge , R. H. Becker , R. L. White , D. J. Helfand

Radio continuum surveys can detect galaxies over a very wide range in redshift, making them powerful tools for studying the distant universe. Until recently, though, identifying the optical counterparts of faint radio sources and measuring…

Astrophysics · Physics 2007-05-23 Elaine M. Sadler , Carole A. Jackson , Russell D. Cannon

Central compact objects (CCOs) constitute a population of radio-quiet, slowly-spinning ($\ge$100 ms) young neutron stars with anomalously high thermal X-ray luminosities. Their spin-down properties imply weak dipole magnetic fields…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Slavko Bogdanov , C. -Y. Ng , Victoria M. Kaspi

There is quite a clear anticorrelation between the intrinsic peak frequency and the overall radio source size in Compact Steep Spectrum (CSS) and GHz Peaked Spectrum (GPS) radio sources as shown by O'Dea (1998). This feature is interpreted…

Astrophysics · Physics 2009-11-07 Daniele Dallacasa

Compact symmetric objects (CSOs) are radio-emitting active galactic nuclei (AGNs) typically with a double-lobed radio structure confined to within 1 kpc. CSOs represent the earliest evolutionary phase of jetted AGNs. Some of them may…

Astrophysics of Galaxies · Physics 2020-07-07 M. Krezinger , S. Frey , T. An , S. Jaiswal , Y. Zhang

We determine the small-scale structure for a large sample of Compact Steep Spectrum (CSS) and Gigahertz Peaked Spectrum (GPS) sources and a sample of larger radio sources at 327 MHz using the technique of Inter-Planetary Scintillation (IPS)…

Astrophysics · Physics 2007-05-23 S. Jeyakumar , D. J. Saikia , A. Pramesh Rao , V. Balasubramanian

Emission in the ultraviolet continuum is a salient signature of the hot, massive and consequently short-lived, stellar population that traces recent or ongoing star formation. With the aim of mapping star forming regions and morphologically…

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 150 MHz, 1.4 GHz, and 3 GHz radio imaging (LoTSS, FIRST and VLASS) and spatially resolved ionized gas characteristics (SDSS IV-MaNGA) for 140 local ($z<0.1$) early-type "red geyser" galaxies. These galaxies have low star…

The properties of the host galaxies of a well-defined sample of 2215 radio-loud AGN with redshifts 0.03 < z < 0.3, defined from the SDSS, are investigated. These are predominantly low radio luminosity sources, with 1.4GHz luminosities of…

Astrophysics · Physics 2008-11-26 P. N. Best , G. Kauffmann , T. M. Heckman , J. Brinchmann , S. Charlot , Z. Ivezic , S. D. M. White

We present 115 compact radio point sources in three galaxies, NGC 5474, NGC 4631 and M51, taken in the most extended (A-)configuration of the Karl G. Jansky Very Large Array at 10GHz. Several of these compact radio point sources have…

Context: The long-standing question concerning jetted subgalactic-size (JSS) radio sources is whether they will evolve into large radio galaxies, die before escaping the host galaxy, or remain indefinitely confined to their compact size.…

Astrophysics of Galaxies · Physics 2025-03-19 C. Stanghellini , M. Orienti , C. Spingola , A. Zanichelli , D. Dallacasa , P. Cassaro , C. P. O'Dea , S. A. Baum , M. Pérez-Torres

Giant radio sources form the linear size extreme of the extra-galactic radio source population. Using the WENSS survey, we have selected a complete sample of these sources. We have investigated the properties of their radio structures. We…