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Related papers: The Broad Line Region in Active Galactic Nuclei

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We consider the stability of an accretion disk wind to cloud formation when subject to a central radiation force. For a vertical launch velocity profile that is Keplerian or flatter and the presence of a significant radiation pressure, the…

Astrophysics · Physics 2007-05-23 A. Y. Poludnenko , E. G. Blackman , A. Frank

Supermassive black holes in galaxies spend majority of their lifetime in the low-luminosity regime, powered by hot accretion flow. Strong winds launched from the hot accretion flow have the potential to play an important role in active…

High Energy Astrophysical Phenomena · Physics 2024-03-04 Fangzheng Shi , Feng Yuan , Zhiyuan Li , Zhao Su , Suoqing Ji

We present evidence for changes in the strength and profile of the iron K-alpha line in Active Galactic Nuclei (AGN), based on X-ray observations with ASCA. There is a clear decrease in the strength of the line with increasing luminosity.…

Astrophysics · Physics 2009-10-30 K. Nandra , I. M. George , R. F. Mushotzky , T. J. Turner , T. Yaqoob

Broad iron emission lines are observed in many accreting systems from black holes in AGN and X-ray binaries to neutron star low-mass X-ray binaries. The origin of the line broadening is often interpreted as due to dynamical broadening and…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Edward M. Cackett , Jon M. Miller

We consider the production of high energy neutrinos and cosmic rays in radio-quiet active galactic nuclei (AGN) or in the central regions of radio-loud AGN. We use a model in which acceleration of protons takes place at a shock in an…

Astrophysics · Physics 2010-11-30 A. P. Szabo , R. J. Protheroe

In Active Galactic Nuclei (AGNs) the presence of a star cluster around the central black hole can have several effects on the dynamics and the emission of the global system. In this paper we analyze the interaction of stellar atmospheres…

Astrophysics · Physics 2009-11-07 Guidetta Torricelli-Ciamponi , Paola Pietrini

The origin of outflow in narrow-line region (NLR) of active galactic nucleus (AGN) is studied in this paper by focusing on the relationship between the [\ion{O}{3}]$\lambda$5007 line profile and the hard X-ray (in a bandpass of 2-10 keV)…

Astrophysics of Galaxies · Physics 2016-03-16 J. Wang , D. W. Xu , J. Y. Wei

We analyze X-ray spectra of heavily obscured (N_H > 10^{24} cm^{-2}) active galaxies obtained with Chandra, concentrating on the iron K alpha fluorescence line. We measure very large equivalent widths in most cases, up to 5 keV in the most…

Astrophysics · Physics 2009-11-07 N. A. Levenson , J. H. Krolik , P. T. Zycki , T. M. Heckman , K. A. Weaver , H. Awaki , Y. Terashima

We show that the recently observed suppression of the gap between the broad line region (BLR) and the narrow line region (NLR) in some AGN can be fully explained by an increase of the gas density in the emitting region. Our model predicts…

Astrophysics of Galaxies · Physics 2016-11-17 T. P. Adhikari , A. Różańska , B. Czerny , K. Hryniewicz , G. J. Ferland

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 present the first quantified, statistical map of broad-line active galactic nucleus (AGN) frequency with host galaxy color and stellar mass in nearby (0.01 < z < 0.11) galaxies. Aperture photometry and z-band concentration measurements…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Jonathan R. Trump , Alexander D. Hsu , Jerome J. Fang , S. M. Faber , David C. Koo , Dale D. Kocevski

We present a compilation of spectral energy distributions of 35 weak AGNs in LINERs using recent data from the published literature. We make use of previously published compilations of data, after complementing and extending them with more…

Astrophysics of Galaxies · Physics 2015-05-18 Michael Eracleous , Jason A. Hwang , Helene M. L. G. Flohic

We present evidence for a broad, ionized Fe K line in the XMM-Newton spectrum of the broad-line radio galaxy (BLRG) 4C+74.26. This is the first indication that the innermost regions of the accretion flow in BLRGs contain thin, radiatively…

Astrophysics · Physics 2009-11-10 D. R. Ballantyne , A. C. Fabian

We present evidence in favour of a link between the luminosity radiatively dissipated in the central engine of radio-loud Active Galactic Nuclei and the kinetic power in their jets. This piece of evidence is based on the relation we find…

Astrophysics · Physics 2015-06-24 Annalisa Celotti , Paolo Padovani , Gabriele Ghisellini

One percent of redshift z~0.1 Active Galactic Nuclei (AGNs) show velocity splitting of a few hundred km/s in the narrow emission lines in spatially integrated spectra. Such line profiles have been found to arise from the bulk motion of…

Astrophysics of Galaxies · Physics 2017-09-12 Yang Lyu , Xin Liu

High signal-to-noise, representative spectra of star-forming galaxies at z~2, obtained via stacking, reveal a high-velocity component underneath the narrow H-alpha and [NII] emission lines. When modeled as a single Gaussian, this broad…

We investigate the virilization of the emission lines Hbeta and Mg II in the sample of 287 Type 1 Active Galactic Nuclei taken from the Sloan Digital Sky Survey database. We explore the connections between the intrinsic line shifts and full…

Astrophysics of Galaxies · Physics 2016-03-23 Sanja Jonic , Jelena Kovacevic-Dojcinovic , Dragana Ilic , Luka C. Popovic

Red Geysers are quiescent galaxies with galactic scale ionised outflows, likely due to low-luminosity Active Galactic Nuclei (AGN). We used Gemini GMOS-IFU observations of the inner $\sim 1.0-3.0$ kpc of nine Red Geysers selected from the…

We queried the Spitzer archive for high-resolution observations with the Infrared Spectrograph of optically selected active galactic nuclei (AGN) for the purpose of identifying sources with resolved fine-structure lines that would enable…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-21 K. M. Dasyra , L. C. Ho , H. Netzer , F. Combes , B. Trakhtenbrot , E. Sturm , L. Armus , D. Elbaz

I review progress made in understanding the nature of the broad-line region (BLR) of active galactic nuclei (AGNs) and the role BLRs play in the AGN phenomenon. The high equivalent widths of the lines imply a high BLR covering factor, and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 C. Martin Gaskell
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