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We investigate the nature of low-luminosity radio-loud active galactic nuclei (RLAGN) selected from the LOFAR Two-metre Sky Survey (LoTSS) first data release (DR1). Using optical, mid-infrared, and radio data, we have conservatively…

The radio luminosity function (RLF) of radio galaxies and radio-loud quasars is often modelled as a broken power-law. The break luminosity is close to the dividing line between the two Fanaroff-Riley (FR) morphological classes for the…

天体物理学 · 物理学 2009-11-13 Christian R. Kaiser , Philip N. Best

We study the cosmic evolution of radio-loud active galactic nuclei (AGNs) using a beaming-minimized sample of 4{,}555 steep-spectrum sources over $0<z\lesssim4$, compiled from the XXL survey, VLA-COSMOS, and other wide-field data sets. We…

星系天体物理 · 物理学 2026-03-17 Wenjie Wang , Zunli Yuan , B. Šlaus , Hongwei Yu , Yu Luo

We present the completed results of a high resolution radio imaging survey of all (~200) low-luminosity active galactic nuclei (LLAGNs) and AGNs in the Palomar Spectroscopic Sample. The high incidences of pc-scale radio nuclei, with…

天体物理学 · 物理学 2009-11-10 Neil M. Nagar , Heino Falcke , Andrew S. Wilson

Low luminosity radio-loud active galactic nuclei (AGN) are generally found in massive red elliptical galaxies, where they are thought to be powered through gas accretion from their surrounding hot halos in a radiatively inefficient manner.…

宇宙学与河外天体物理 · 物理学 2012-06-05 R. M. J. Janssen , H. J. A. Rottgering , P. N. Best , J. Brinchmann

We present a new determination of the optical luminosity function (OLF) of active galactic nuclei (AGN) at low redshifts (z<0.15) based on Hubble Space Telescope (HST) observations of X-ray-selected AGN. The HST observations have allowed us…

天体物理学 · 物理学 2015-06-24 D. Londish , B. J. Boyle , D. J. Schade

We present the completed results of a high resolution radio imaging survey of all (around 200) low-luminosity active galactic nuclei (LLAGNs) in the Palomar spectroscopic Sample of all (around 470) nearby bright northern galaxies. The high…

天体物理学 · 物理学 2007-05-23 N. M. Nagar , H. Falcke , A. S. Wilson

The radio luminosity functions (RLFs) of active galactic nuclei (AGNs) are traditionally measured based on total emission, which doesn't reflect the current activity of the central black hole. The increasing interest in compact radio cores…

星系天体物理 · 物理学 2018-12-26 Zunli Yuan , Jiancheng Wang , D. M. Worrall , Bin-Bin Zhang , Jirong Mao

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…

天体物理学 · 物理学 2008-11-26 W. H. de Vries , J. A. Hodge , R. H. Becker , R. L. White , D. J. Helfand

We explore the cosmic evolution of radio AGN with low radio powers (L_1.4GHz < 5\times10^25 W/Hz) out to z=1.3 using to-date the largest sample of ~600 low luminosity radio AGN at intermediate redshift drawn from the VLA-COSMOS survey. We…

We have used the European VLBI Network (EVN) to observe a sample of Lyman Break Analogs (LBAs), nearby (z < 0.3) galaxies with properties similar to the more distant Lyman Break Galaxies (LBGs). The study of LBGs may help define the…

宇宙学与河外天体物理 · 物理学 2015-06-04 R. Alexandroff , R. A. Overzier , Z. Paragi , A. Basu-Zych , T. Heckman , G. Kauffmann , S. Bourke , A. Lobanov , A. Ptak , D. Schiminovich

We present a sub-arcsec resolution radio imaging survey of a sample of 76 low-luminosity active galactic nuclei (LLAGN) that were previously not detected with the Very Large Array at 15 GHz. Compact, parsec-scale radio emission has been…

The question as to whether the distribution of radio-loudness in active galactic nuclei (AGN) is actually bimodal has been discussed extensively in the literature. Futhermore, there have been claims that radio-loudness depends on black hole…

天体物理学 · 物理学 2009-11-13 Stephen E. Rafter , D. Michael Crenshaw , Paul J. Wiita

We detect and study the properties of faint radio AGN in Luminous Red Galaxies (LRGs). The LRG sample comprises 760,000 objects from a catalog of LRG photometric redshifts constructed from the Sloan Digital Sky Survey (SDSS) imaging data,…

星系天体物理 · 物理学 2015-05-13 J. A. Hodge , G. R. Zeimann , R. H. Becker , R. L. White

(abbreviated): This paper presents the results of a high resolution radio imaging survey of all known (96) low-luminosity active galactic nuclei (LLAGNs) at D<19Mpc. We find that almost half of all LINERs and low-luminosity Seyferts have…

天体物理学 · 物理学 2009-11-07 N. M. Nagar , H. Falcke , A. S. Wilson , J. S. Ulvestad

We develop a formalism to model the luminosity functions (LFs) of radio-loud Active Galactic Nuclei (AGN) at GHz frequencies by the cosmological evolution of the supermassive black hole (SMBH). The mass function and Eddington ratio…

宇宙学与河外天体物理 · 物理学 2021-06-30 Marco Tucci , Luigi Toffolatti

In order to determine the incidence of black hole accretion-driven nuclear activity in nearby galaxies, as manifested by their radio emission, we have carried out a high-resolution Multi-Element Radio-Linked Interferometer Network (MERLIN)…

天体物理学 · 物理学 2009-11-11 M. E. Filho , P. D. Barthel , L. C. Ho

We present radio Active Galactic Nuclei (AGN) luminosity functions over the redshift range 0.005 < z < 0.75. The sample from which the luminosity functions are constructed is an optical spectroscopic survey of radio galaxies, identified…

I review observational properties of low power radio loud AGN. High resolution VLBI observations allow the estimate of the jet velocity and orientation with respect to the line of sight and the determination of the Doppler factor. These…

天体物理学 · 物理学 2009-04-14 G. Giovannini , M. Giroletti

This paper presents a new sample of BL Lac objects selected from a deep (30 mJy) radio survey of flat spectrum radio sources (the CLASS blazar survey, henceforth CBS). The sample is one of the largest well defined samples in the low power…

宇宙学与河外天体物理 · 物理学 2015-06-12 M. J. M. Marcha , A. Caccianiga
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