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Related papers: Constraining AGN Torus Sizes with Optical and Mid-…

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Recent high angular resolution observations resolved for the first time the mid-infrared (MIR) structure of nearby active galactic nuclei (AGN). Surprisingly, they revealed that a major fraction of their MIR emission comes from the polar…

Astrophysics of Galaxies · Physics 2017-08-30 Marko Stalevski , Daniel Asmus , Konrad R. W. Tristram

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

The spectral energy distributions and infrared (IR) spectra of a sample of obscured AGNs selected in the mid-IR are modeled with recent clumpy torus models to investigate the nature of the sources, the properties of the obscuring matter,…

Astrophysics · Physics 2010-03-19 M. Polletta , D. Weedman , S. Hoenig , C. J. Lonsdale , H. E. Smith , J. Houck

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 studied the physical parameters of a sample comprising of all Spitzer/IRS public spectra of Seyfert galaxies in the mid-infrared (5.2-38$\mu$m range) under the active galactic nuclei (AGN) unified model. We compare the observed spectra…

Astrophysics of Galaxies · Physics 2016-09-29 Anelise Audibert , Rogério Riffel , Dinalva A. Sales , Miriani G. Pastoriza , Daniel Ruschel-Dutra

From extensive radiative transfer calculations we find that clumpy torus models with \No \about 5--15 dusty clouds along radial equatorial rays successfully explain AGN infrared observations. The dust has standard Galactic composition, with…

Astrophysics · Physics 2011-02-11 Maia Nenkova , Matthew M. Sirocky , Robert Nikutta , Zeljko Ivezic , Moshe Elitzur

In order to understand the diversity of classes observed in active galactic nuclei (AGN), a geometrically and optically thick torus of gas and dust is required to obscure the central engine depending on the line of sight to the observer. We…

We investigate the use of MIR PAH bands, continuum and emission lines as probes of star-formation and AGN activity in a sample of 100 'normal' and local (z~0.1) emission-line galaxies. The MIR spectra were obtained with the Spitzer Space…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Marie Treyer , D. Schiminovich , B. D. Johnson , M. O'Dowd , C. D. Martin , T. Wyder , S. Charlot , T. Heckman , L. Martins , M. Seibert , J. M. van der Hulst

The time delay between flux variations in different wavelength bands can be used to probe the inner regions of active galactic nuclei (AGN). Here, we present the first measurements of the time delay between optical and near-infrared (NIR)…

At distances from the active galaxy nucleus (AGN) where the ambient temperature falls below ~1500-1800 K, dust is able to survive. It is thus possible to have a large dusty structure present which surrounds the AGN. This is the first of two…

We study the geometry of the AGN obscurer in IRAS 09104+4109, an IR-luminous, radio-intermediate FR-I source at $z=0.442$, using infrared data from Spitzer and Herschel, X-ray data from Nustar, Swift, Suzaku, and Chandra, and an optical…

Active galactic nuclei (AGN) are high luminosity sources powered by accretion of matter onto SMBHs located at the centres of galaxies. The SMBH is surrounded by a broad emission line region (BLR) and a dusty torus. It is difficult to study…

Astrophysics of Galaxies · Physics 2019-05-07 Amit Kumar Mandal , Suvendu Rakshit , Indrani Pal , Chelliah Subramonian Stalin , Ram Sagar , Blesson Mathew

Context. The supermassive black hole, Sagittarius (Sgr) A*, in the centre of our Galaxy has the largest angular size in the sky among all astrophysical black holes. Its shadow, assuming no rotation, spans ~ 50 microarcsec. Resolving such…

Astrophysics of Galaxies · Physics 2015-06-19 F. H. Vincent , W. Yan , O. Straub , A. A. Zdziarski , M. A. Abramowicz

Several models of nuclear dust in active galactic nuclei (AGN) have been presented in the literature to determine its physical and geometrical properties, usually assuming the dust density distribution as the main aspect producing…

Dust torus plays the key role in determining active galactic nuclei (AGN) observational appearance. Here, the scenario of accretion regulated central dust torus is tested for the first time in the individual changing-look AGN (CLAGN) SDSS…

Astrophysics of Galaxies · Physics 2026-04-09 Zhang XueGuang

We present the measurement of the line-of-sight extinction of the dusty torus for a large number of obscured active galactic nuclei (AGNs) based on the reddening of the colour of the variable flux component in near-infrared (NIR)…

We present 31.5 micron imaging photometry of 11 nearby Seyfert galaxies observed from the Stratospheric Observatory For Infrared Astronomy (SOFIA) using the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST). We tentatively…

We present our sixth work in a series dedicated to variability studies of active galactic nuclei (AGN) based on the survey of the COSMOS field by the VLT Survey Telescope (VST). Its 54 r-band visits over 3.3 yr and single-visit depth of…

Astrophysics of Galaxies · Physics 2022-08-24 D. De Cicco , F. E. Bauer , M. Paolillo , P. Sánchez-Sáez , W. N. Brandt , F. Vagnetti , G. Pignata , M. Radovich , M. Vaccari

In Unification Models, Active Galactic Nuclei (AGN) are believed to be surrounded by an axisymmetric structure of dust and gas, which greatly influences their observed properties according to the direction from which they are observed. The…

Astrophysics · Physics 2009-11-11 E. Ibar , P. Lira

Dust plays a central role in the unification theory of active galactic nuclei (AGNs). Whether the dust that forms the torus around an AGN is tenth-$\mu$m-sized like interstellar grains or much larger has a profound impact on correcting for…

Astrophysics of Galaxies · Physics 2017-05-10 Z. Z. Shao , B. W. Jiang , Aigen Li