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Related papers: Testing the AGN Unification Model in the Infrared

200 papers

Spectral energy distributions (SEDs) of the central few tens of parsec region of some of the nearest, most well studied, active galactic nuclei (AGN) are presented. These genuine AGN-core SEDs, mostly from Seyfert galaxies, are…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 M. A. Prieto , J. Reunanen , K. R. W. Tristram , N. Neumayer , J. A. Fernandez-Ontiveros , M. Orienti , K. Meisenheimer

We investigated the emission of active galactic nuclei dusty tori in the infrared domain, with a focus on the 10 micron silicate feature. We modeled the dusty torus as a clumpy two-phase medium with high-density clumps and a low-density…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-14 Marko Stalevski , Jacopo Fritz , Maarten Baes , Theodoros Nakos , Luka C. Popovic

We present the first results from a mid-infrared survey of local Active Galactic Nuclei (AGN) using the CanariCam (CC) instrument on the 10.4m Gran Telescopio Canarias (GTC). We are obtaining sub-arcsecond angular resolution (0.3-0.6…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Almudena Alonso-Herrero

We present new calculations of the CAT3D clumpy torus models, which now include a more physical dust sublimation model as well as AGN anisotropic emission. These new models allow graphite grains to persist at temperatures higher than the…

Context: We investigate mid-infrared and X-ray properties of the dusty torus in unification scenarios for active galactic nuclei. Aims: We use the relation between mid IR and hard X-ray luminosities to constrain AGN unification scenarios.…

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

We present results from model fitting to the Spectral Energy Distribution (SED) of a homogeneous sample of Seyfert II galaxies drawn from the $12\mu$m Galaxy Sample. Imaging and nuclear flux measurements are presented in an accompanying…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Paulina Lira , Liza Videla , Yanling Wu , Almudena Alonso-Herrero , David M. Alexander , Martin Ward

We assume that dust near active galactic nuclei (AGN) is distributed in a torus-like geometry, which may be described by a clumpy medium or a homogeneous disk or as a combination of the two (i.e. a 2-phase medium). The dust particles…

Astrophysics of Galaxies · Physics 2015-11-11 Ralf Siebenmorgen , Frank Heymann , Andreas Efstathiou

We have observed a sample of Seyfert (Sy) galaxies with the global Very Long Baseline Interferometry (VLBI) to test the predictions of the unification scheme for the Sy galaxies which hypothesises that Sys of Type 1 and of Type 2 constitute…

Astrophysics · Physics 2007-05-23 Dharam Vir Lal

Recent observations of NGC 1068 and other AGN support the idea of a geometrically and optically thick dust torus surrounding the central supermassive black hole and accretion disk of AGN. In type 2 AGN, the torus is seen roughly edge-on,…

Astrophysics · Physics 2007-05-23 S. F. Hoenig , T. Beckert , K. Ohnaka , G. Weigelt

Dust reprocesses the intrinsic radiation of active galactic nuclei (AGNs) to emerge at longer wavelengths. The observed mid-infrared (MIR) luminosity depends fundamentally on the luminosity of the central engine, but in detail it also…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 N. A. Levenson , J. T. Radomski , C. Packham , R. E. Mason , J. J. Schaefer , C. M. Telesco

Unified schemes of active galactic nuclei (AGN) require an obscuring dusty torus around the central source, giving rise to type 1 line spectrum for pole-on viewing and type 2 characteristics in edge-on sources. Infrared radiation at its…

Astrophysics · Physics 2007-05-23 Moshe Elitzur , Maia Nenkova , Zeljko Ivezic

According to unified schemes of Active Galactic Nuclei (AGN), the central engine is surrounded by dusty, optically thick clouds in a toroidal structure. We have recently developed a formalism that for the first time takes proper account of…

Astrophysics · Physics 2009-11-13 Maia Nenkova , Matthew M. Sirocky , Zeljko Ivezic , Moshe Elitzur

We summarize recent results on the infrared (IR) nuclear properties of Seyfert galaxies. 100% of all Seyfert 1-1.9$ and ~50% of all Seyfert 2s in the CfA and RSA samples observed with HST/NICMOS show nuclear point sources at 1.6micron. We…

Astrophysics · Physics 2007-05-23 Almudena Alonso-Herrero

In this paper we further explore the properties of the HERschel Ultra Luminous Infrared Galaxy Survey (HERUS) sample of 42 local ultraluminous infrared galaxies (ULIRGs) with our recently developed Bayesian spectral energy distribution…

Astrophysics of Galaxies · Physics 2025-02-21 Charalambia Varnava , Andreas Efstathiou , Duncan Farrah , Dimitra Rigopoulou

The range of currently proposed active galactic nucleus (AGN) far-infrared templates results in uncertainties in retrieving host galaxy information from infrared observations and also undermines constraints on the outer part of the AGN…

Astrophysics of Galaxies · Physics 2017-05-26 Jianwei Lyu , George H. Rieke

We are conducting a large observing program with the Spitzer Space Telescope to determine the mid-to-far infrared spectral energy distributions of a well-defined sample of 87 nearby, 12 micron-selected Seyfert galaxies. In this paper we…

Based on large optical and mid-infrared (IR) surveys, we investigate the relation between nuclear activity in local Seyfert 2 galaxies and galaxy interactions using a statistical neighbour counting technique. At the same level of host…

Astrophysics of Galaxies · Physics 2015-06-23 Li Shao , Cheng Li , Guinevere Kauffmann , Jing Wang

Unified schemes of active galactic nuclei (AGN) require an obscuring dusty torus around the central engine. Torus sizes of hundreds of parsecs were deduced from early theoretical modeling efforts, but high-resolution IR observations now…

Astrophysics · Physics 2007-05-23 Moshe Elitzur

Two families of models of dusty tori in AGNs (moderately thick and extended versus very thick and compact) are tested against available observations. The confrontation suggests that the former class better explains the IR broad-band spectra…

Astrophysics · Physics 2009-10-30 Gian Luigi Granato , Luigi Danese , Alberto Franceschini

Dusty tori around active galactic nuclei (AGNs) play an important role in the classification of Seyfert galaxies. Therefore, physical properties of dusty tori are of great interest. We briefly introduce three statistical studies…

Astrophysics · Physics 2007-05-23 Yoshiaki Taniguchi , Takashi Murayama , Hideaki Mouri