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Related papers: On the two main classes of Active Galactic Nuclei

200 papers

Basing our analysis on ROGUE I, a catalog of over 32,000 radio sources associated with optical galaxies, we provide two diagnostics to select the galaxies where the radio emission is due to an active galactic nucleus (AGN). Each of these…

A wide-frequency radio study of Active Galactic Nuclei (AGN) is crucial to evaluate the intervening radiative mechanisms responsible for the observed emission and relate them with the underlying accretion physics. We present wide frequency…

Binary or dual active galactic nuclei (DAGN) are expected from galaxy formation theories. However, confirmed DAGN are rare and finding these systems has proved to be challenging. Recent systematic searches for DAGN using double-peaked…

Astrophysics of Galaxies · Physics 2018-05-09 Rubinur Khatun , M. Das , P. Kharb

We recently argued (Meyer 2011) that the collective properties of radio loud active galactic nuclei point to the existence of two families of sources, one of powerful sources with single velocity jets and one of weaker jets with significant…

High Energy Astrophysical Phenomena · Physics 2011-11-22 Markos Georganopoulos , Eileen T. Meyer , Giovanni Fossati , Matthew L. Lister

I describe the different classes of Active Galactic Nuclei (AGN) and the basic tenets of unified schemes. I then review the properties of the extragalactic sources detected in the GeV and TeV bands, showing that the vast majority of them…

Astrophysics · Physics 2009-06-23 P. Padovani

Active Galactic Nuclei (AGNs) are characterized by emission of radiation over more than 10 orders of magnitude in frequency. Therefore, the execution of extensive surveys of the sky, with different types of detectors, is providing the…

Jets associated with Active Galactic Nuclei (AGN) have been observed for almost a century, initially at optical and radio wavelengths. They are now widely accepted as "exhausts" produced electromagnetically by the central, spinning, massive…

High Energy Astrophysical Phenomena · Physics 2015-11-25 R. Blandford , W. East , K. Nalewajko , Y. Yuan , J. Zrake

That active galactic nuclei (AGN) with jets can alternately enhance as well as suppress star formation rates, explains the location and slope of radio loud AGN on the star formation rate-stellar mass plane. Here, we explore 860 type 1 and 2…

Astrophysics of Galaxies · Physics 2022-07-06 D. Garofalo , G. Mountrichas

We have examined a subset of 18 active galactic nuclei (AGNs) drawn from a sample of 81 galaxies that possess double-peaked narrow optical emission line spectra in the Sloan Digital Sky Survey, have two optical AGN emission components…

Historically, Seyfert nuclei have been considered to be radio-quiet active galactic nuclei (AGNs). We question this widely held assumption by showing that the distribution of the radio-to-optical luminosity ratio R, when properly measured…

Astrophysics · Physics 2009-11-06 Luis C. Ho , Chien Y. Peng

We study two aspects of the differences between Active Galactic Nuclei (AGN) of the two Fanaroff-Riley types in order to investigate the causes of the F-R divide. We (a) contrast the properties of the optical cores in beamed and unbeamed…

Astrophysics · Physics 2009-11-07 P. Kharb , P. Shastri , D. C. Gabuzda

We constructed a sample of 23,344 radio-loud active galactic nuclei (RLAGN) from the catalogue derived from the LOFAR Two-Metre Sky Survey (LoTSS) survey of the HETDEX Spring field. Although separating AGN from star-forming galaxies remains…

We introduce a novel machine learning dataset tailored for the classification of bent radio active galactic nuclei (AGN) in astronomical observations. Bent radio AGN, distinguished by their curved jet structures, provide critical insights…

Active galactic nuclei (AGN) are supermassive black holes with luminous accretion disks found in some galaxies, and are thought to play an important role in galaxy evolution. However, traditional optical spectroscopy for identifying AGN…

Astrophysics of Galaxies · Physics 2022-12-16 Ziting Guo , John F. Wu , Chelsea E. Sharon

Double-peaked [O III]5007, profiles in active galactic nuclei (AGNs) may provide evidence for the existence of dual AGNs, but a good diagnostic for selecting them is currently lacking. Starting from $\sim$ 7000 active galaxies in SDSS DR7,…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 J. -M Wang , Y. -M. Chen , C. Hu , W. -M. Mao , S. Zhang , W. -H. Bian

We collect data at all frequencies for the new sources classified as unknown active galactic nuclei (AGNs) in the latest Burst Alert Telescope (BAT) all-sky hard X-ray catalog. Focusing on the 36 sources with measured redshift, we compute…

High Energy Astrophysical Phenomena · Physics 2021-04-07 Luca Giuliani , Gabriele Ghisellini , Tullia Sbarrato

Active galactic nuclei (AGNs) with double-peaked [O III] lines are suspected to be sub-kpc or kpc-scale binary AGNs. However, pure gas kinematics can produce the same double-peaked line profile in spatially integrated spectra. Here we…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Hai Fu , Lin Yan , Adam D. Myers , Alan Stockton , S. G. Djorgovski , G. Aldering , Jeffrey A. Rich

We present a model describing the evolution of Fanaroff-Riley type I and II radio AGN, and the transition between these classes. We quantify galaxy environments using a semi-analytic galaxy formation model, and apply our model to a…

Astrophysics of Galaxies · Physics 2015-06-11 Ross J. Turner , Stanislav S. Shabala

We explore host galaxy properties and environment of a sample of Type 1 and 2 active galactic nuclei (AGN) taken from the COSMOS2015 catalog, within 0.3 $\leq z \leq$ 1.1 selected for their emission in X-rays, optical spectra and SED…

Astrophysics of Galaxies · Physics 2018-07-11 Carlos Guillermo Bornancini , Diego García Lambas

Number of monitoring observations of continuum emission from Active Galactic Nuclei (AGNs) have been made in optical--X-ray bands. The results obtained so far show (i) random up and down on timescales longer than decades, (ii) no typical…

Astrophysics · Physics 2007-05-23 T. Kawaguchi , S. Mineshige