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Related papers: A Model for Type 2 Coronal Line Forest (CLiF) AGN

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A sample of 229618 narrow emission-line galaxies is used to establish two new unambiguous type of evidence for supermassive black holes at the center of their nuclei: 1) the Seyfert 2 galaxies and LINERs follow the same characteristic power…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-14 J. P. Torres-Papaqui , R. Coziol , H. Andernach , R. A. Ortega-Minakata , D. M. Neri-Larios , I. Plauchu-Frayn

One of the most intriguing open issues in galaxy evolution is the structure and evolution of active galactic nuclei (AGN) that emit intense light believed to come from an accretion disk near a super-massive black hole (Rees 1984,…

Astrophysics of Galaxies · Physics 2014-11-26 Beatriz Villarroel , Andreas J. Korn

The massive black hole (BH) population in dwarf galaxies ($M_{\rm BH} \lesssim 10^5~M_\odot$) can provide strong constraints on the origin of BH seeds. However, traditional optical searches for active galactic nuclei (AGNs) only reliably…

Astrophysics of Galaxies · Physics 2022-06-24 M. Molina , A. E. Reines , L. J. Latimer , V. Baldassare , Sheyda Salehirad

We present an analysis of broad emission lines observed in moderate-luminosity active galactic nuclei (AGNs), typical of those found in X-ray surveys of deep fields, with the aim to test the validity of single-epoch virial black hole mass…

The ionizing fluxes from quasars and other active galactic nuclei (AGN) are critical for interpreting their emission-line spectra and for photoionizing and heating the intergalactic medium (IGM). Using far-ultraviolet spectra from the…

Astrophysics of Galaxies · Physics 2015-06-22 Matthew L. Stevans , J. Michael Shull , Charles W. Danforth , Evan M. Tilton

Here we discuss the effects of strong gravity that can be observed in electromagnetic spectra of active galactic nuclei (AGN). According to the unification model of an AGN, there is a supermassive black hole ($10^7 - 10^9 M_\odot$) in its…

Astrophysics · Physics 2009-06-25 P. Jovanović , L. Č. Popović

We present high quality (high signal-to-noise ratio and moderate spectral resolution) near-infrared (near-IR) spectroscopic observations of 23 well-known broad-emission line active galactic nuclei (AGN). Additionally, we obtained…

We present archival high resolution X-ray imaging observations of 25 nearby LINERs observed by ACIS on board Chandra. This sample builds on our previously published proprietary and archival X-ray observations, and includes the complete set…

Astrophysics · Physics 2009-11-13 S. Satyapal , R. P. Dudik , B. O'Halloran , M. Gliozzi

Over recent years there has been mounting evidence that accreting supermassive black holes in active galactic nuclei (AGN) and stellar mass black holes have similar observational signatures: thermal emission from the accretion disk, X-ray…

The central engines of active galactic nuclei (AGN) contain cold, dense material as well as hot X-ray emitting gas. The standard paradigm for the engine geometry is a cold thin disc sandwiched between hot X-ray coronae. Strong support for…

Astrophysics · Physics 2015-06-24 Sean A. Hartnoll , Eric G. Blackman

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

Using a suite of X-ray, mid-IR and optical active galactic nuclei (AGN) luminosity indicators, we search for Compton-thick (CT) AGNs with intrinsic L_X>10^42erg/s at z~0.03-0.2, a region of parameter space which is currently poorly…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Andy Goulding , David Alexander , James Mullaney , Jonathan Gelbord , Ryan Hickox , Martin Ward , Mike Watson

In order to better understand how active galactic nuclei (AGN) effect the interstellar media of their host galaxies, we perform a meta-analysis of the CO emission for a sample of $z=0.01-4$ galaxies from the literature with existing CO…

Astrophysics of Galaxies · Physics 2019-07-10 Allison Kirkpatrick , Chelsea Sharon , Erica Keller , Alexandra Pope

A crucial difficulty in understanding the nature of the putative accretion disk in AGNs is that some of its key intrinsic spectral signatures cannot be observed directly. The strong emissions from the broad-line region (BLR) and the…

The INTEGRAL mission provides a large data set for studying the hard X-ray properties of AGN and allows to test the unified scheme for AGN. We present results based on the analysis of 199 AGN. A difference between the Seyfert types is…

High Energy Astrophysical Phenomena · Physics 2010-01-26 V. Beckmann , C. Ricci , S. Soldi , J. Alfonso-Garzon , T. J. -L. Courvoisier , A. Domingo , N. Gehrels , P. Lubinski , J. M. Mas-Hesse , A. A. Zdziarski

We study the properties of a sample of 211 heavily-obscured Active Galactic Nucleus (AGN) candidates in the Extended Chandra Deep Field-South selecting objects with f_24/f_R>1000 and R-K>4.5. Of these, 18 were detected in X-rays and found…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 E. Treister , C. Cardamone , K. Schawinski , C. M. Urry , E. Gawiser , S. Virani , P. Lira , J. Kartaltepe , M Damen , E. N. Taylor , E. Le Floc'h , Stephen Justham , A. Koekemoer

There is substantial evidence for a connection between star formation in the nuclear region of a galaxy and growth of the central supermassive black hole. Furthermore, starburst activity in the region around an active galactic nucleus (AGN)…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Jonathan N. Armour , David R. Ballantyne

[abridged] We use the latest release of CIGALE, a galaxy SED fitting model relying on energy balance, to study the influence of an AGN in estimating both the SFR and stellar mass in galaxies, as well as the contribution of the AGN to the…

From detailed spectral analysis of a large sample of low-redshift active galactic nuclei (AGNs) selected from the Sloan Digital Sky Survey, we demonstrate---statistically for the first time---that narrow optical Fe II emission lines, both…

Astrophysics of Galaxies · Physics 2010-09-14 Xiao-Bo Dong , Luis C. Ho , Jian-Guo Wang , Ting-Gui Wang , Huiyuan Wang , Xiaohui Fan , Hongyan Zhou

Aims. High angular resolution N-band imaging is used to discern the torus of active galactic nuclei (AGN) from its environment in order to allow a comparison of its mid-infrared properties to the expectations of the unified scenario for…

Astrophysics of Galaxies · Physics 2009-11-13 Hannes Horst , Wolfgang J. Duschl , Poshak Gandhi , Alain Smette