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Related papers: Some Comments related to AGN Radio Loudness

200 papers

We use a recently released SDSS catalog of X-ray emitting AGNs in conjunction with the FIRST 20cm radio survey to investigate the black hole fundamental plane relationship between the 1.4GHz radio luminosity ($L_r$), 0.1-2.4 keV X-ray…

Astrophysics · Physics 2009-11-13 Zhao-Yu Li , Xue-Bing Wu , Ran Wang

To gain new insights into the radio-loud/radio-quiet dichotomy reported for active galactic nuclei, we examine radio loudness as a function of Eddington ratio for a previously published sample of 199 AGN from five different populations.…

Astrophysics of Galaxies · Physics 2015-05-28 J. W. Broderick , R. P. Fender

We investigate how the total radio luminosity of AGN-powered radio sources depends on their accretion luminosity and the central black hole mass. We find that AGNs form two distinct and well separated sequences on the radio-loudness -…

Astrophysics · Physics 2007-07-17 L. Stawarz , M. Sikora , J. -P. Lasota

The majority of nearby radio-loud AGN are found in massive, old elliptical galaxies with weak emission lines. At high redshifts,however, most known radio AGN have strong emission lines. In this paper, we examine a subset of radio AGN with…

Astrophysics · Physics 2009-11-13 Guinevere Kauffmann , Timothy M. Heckman , Philip N. Best

We have found empirically that the radio loudness of AGN can be understood as function of both the X-ray and optical luminosity. This way of considering the radio loudness was inspired by the hardness-intensity diagrams for X-ray binaries,…

Astrophysics · Physics 2008-11-26 Sebastian Jester , Elmar Koerding , Rob Fender

The black hole (BH) mass in the centre of AGN has been estimated for a sample of radio-selected flat-spectrum quasars to investigate the relationship between BH mass and radio properties of quasars. We have used the virial assumption with…

Astrophysics · Physics 2009-11-07 Alicia Oshlack , Rachel Webster , Matthew Whiting

The determination of the central black hole mass is crucial to the understanding of AGN physics. In this paper we briefly review some methods that are currently used to estimate the black hole mass of AGNs. Particularly we demonstrate the…

Astrophysics · Physics 2007-05-23 Xue-Bing Wu , F. K. Liu , R. Wang , M. Z. Kong , J. L. Han

We investigate how the total radio luminosity of AGN-powered radio sources depends on their accretion luminosity and the central black hole mass. Our studies cover about seven orders of magnitude in accretion luminosity and the full range…

Astrophysics · Physics 2008-11-26 M. Sikora , L. Stawarz , J. -P. Lasota

We use a comprehensive database of black hole masses and nuclear luminosities to investigate the relationship between radio emission and black hole mass. Our sample covers a wide range of nuclear activity, from nearby inactive nuclei to…

Astrophysics · Physics 2008-11-26 Luis C. Ho

An empirical relation between the broad line region (BLR) size and optical continuum luminosity is often adopted to estimate the BLR size and then the black hole mass of AGNs. However, optical luminosity may not be a good indicator of…

Astrophysics · Physics 2009-11-10 Xue-Bing Wu , R. Wang , M. Z. Kong , F. K. Liu , J. L. Han

A toy model for jet powers and radio loudness of active galactic nuclei (AGNs) is proposed based on the coexistence of the Blandford-Znajek (BZ) and magnetic coupling (MC) processes (CEBZMC) in black hole (BH) accretion disc. It turns out…

Astrophysics · Physics 2016-08-30 Yong-Chun Ye , Ding-Xiong Wang

We used the widths of H$\beta$ and [OIII] emission lines to investigate the black hole--bulge relation in radio-loud AGNs, radio-quiet AGNs and NLS1s. The central black hole mass, $M_{bh}$, is estimated from the H$\beta$ line width and the…

Astrophysics · Physics 2009-11-10 W. Bian , Y. Zhao

We have studied the host galaxies of a sample of radio-loud AGN spanning more than four decades in the energy output of the nucleus. The core sample includes 40 low-power sources (BL Lac objects) and 22 high-power sources (radio-loud…

Astrophysics · Physics 2009-11-07 Matthew O'Dowd , C. Megan Urry , Riccardo Scarpa

The most massive black holes lie in the most massive elliptical galaxies, and at low-z all radio-loud AGNs lie in giant ellipticals. This strongly suggests a link between radio-loudness and black hole mass. We argue that the increase in the…

Astrophysics · Physics 2009-10-31 Mark Lacy , Susan Ridgway , Neil Trentham

A recent revision of black hole scaling relations (Kormendy & Ho 2013), indicates that the local mass density in black holes should be increased by up to a factor of five with respect to previously determined values. The local black hole…

Astrophysics of Galaxies · Physics 2015-02-11 A. Comastri , R. Gilli , A. Marconi , G. Risaliti , M. Salvati

The recent development of unified theories of active galactic nuclei (AGN) has indicated that there are two physically distinct classes of these objects - radio-loud and radio-quiet. The primary observational distinctions between the two…

Astrophysics · Physics 2016-08-30 Andrew S. Wilson , Edward J. M. Colbert

I review how AGN black hole masses are calculated from emission-line reverberation-mapping data, with particular attention to both assumptions and caveats. I discuss the empirical relationship between AGN luminosity and broad-line region…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-21 Bradley M. Peterson

We have reanalyzed in a consistent way existing reverberation data for 35 AGNs for the purpose of refining the black hole masses derived from these data. We find that the precision (or random component of the error) of reverberation-based…

Astrophysics · Physics 2009-11-10 Bradley M. Peterson

We investigate the conjecture by Sikora, Stawarz & Lasota (2007) that the observed AGN--radio-loudness bimodality can be explained by the morphology-related bimodality of black-hole spin distribution in the centers of galaxies: central…

Astrophysics · Physics 2009-11-13 Marta Volonteri , Marek Sikora , Jean-Pierre Lasota

Radio mode feedback, in which most of the energy of an active galactic nucleus (AGN) is released in a kinetic form via radio-emitting jets, is thought to play an important role in the maintenance of massive galaxies in the present-day…

Astrophysics of Galaxies · Physics 2015-06-22 W. Ishibashi , M. W. Auger , D. Zhang , A. C. Fabian