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Related papers: On donuts and crumbs: A brief history of torus mod…

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The dusty environments (= "dust tori'') of AGN are now in reach of observations. Following our paper I on ground-based mid-IR spectro-photometry (H\"onig et al. 2010), we present an upgrade to our radiative transfer model of 3-dimensional…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 S. F. Hoenig , M. Kishimoto

We modeled the AGN dusty torus as a clumpy two-phase medium, with high-density clumps embedded in a low-density interclump dust. To obtain spectral energy distributions and images of the torus at different wavelengths, we employed the 3D…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-18 Marko Stalevski , Jacopo Fritz , Maarten Baes , Luka C. Popovic

We present 3-dimensional radiative transfer models for clumpy dust tori around AGN. Our method combines Monte Carlo simulations of individual dust clouds with the actual 3-dimensional distribution of clouds in the torus. The model has been…

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

We investigate the emission of active galactic nuclei (AGN) dusty tori in the infrared domain. Following theoretical predictions coming from hydrodynamical simulations, we model the dusty torus as a 3D two-phase medium with high-density…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-29 Marko Stalevski , Jacopo Fritz , Maarten Baes , Theodoros Nakos , Luka C. Popovic

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 emission is an important tool in studies of star-forming clouds, as a tracer of column density and indirectly via the dust evolution that is connected to the history and physical conditions of the clouds. We examine radiative transfer…

Astrophysics of Galaxies · Physics 2024-01-24 M. Juvela

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

These proceedings are based on an invited review talk at the 7th Meeting on Cosmic Dust. The scope of the meeting was broad, covering dust-related topics in areas from comets to debris disks and high-redshift galaxies. This is therefore…

Astrophysics of Galaxies · Physics 2015-10-14 Rachel E. Mason

Present AGN models aiming to account for the observed infrared SEDs consider a physical description of the dust and a solution of the radiative transfer problem. Mid infrared spectra obtained at different spatial scales are presented. They…

Astrophysics · Physics 2009-11-10 Ralf Siebenmorgen , Andreas Efstathiou

This letter presents a revised radiative transfer model for the infrared (IR) emission of active galactic nuclei (AGN). While current models assume that the IR is emitted from a dusty torus in the equatorial plane of the AGN, spatially…

Astrophysics of Galaxies · Physics 2017-04-05 Sebastian F. Hönig , Makoto Kishimoto

Tori of Active Galactic Nuclei are made up of a mixture of hot and cold gas, as well as dust. In order to protect the dust grains from destruction by the hot gas as well as by the energetic radiation of the accretion disk, the dust is often…

Astrophysics · Physics 2009-11-13 M. Schartmann , K. Meisenheimer , M. Camenzind , S. Wolf , K. R. W. Tristram , Th. Henning

This work focuses on the properties of dusty tori in active galactic nuclei (AGN) derived from the comparison of SDSS type 1 quasars with mid-Infrared (MIR) counterparts and a new, detailed torus model. The infrared data were taken by the…

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 construct a radiation-hydrodynamics model for the obscuring toroidal structure in active galactic nuclei. In this model the obscuration is produced at parsec scale by a dense, dusty wind which is supported by infrared radiation pressure…

High Energy Astrophysical Phenomena · Physics 2015-05-30 A. Dorodnitsyn , G. S. Bisnovatyi-Kogan , T. Kallman

Optical/UV photons and even harder radiation components in galaxies are absorbed and scattered by dust and re-emitted at infrared wavelengths. For a better understanding of the obscured regions of the galaxies detailed models of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Ralf Siebenmorgen , Frank Heymann

In the last decades, several multiwavelength studies have been dedicated to exploring the properties of the obscuring material in active galactic nuclei (AGN). Various models have been developed to describe the structure and distribution of…

We present model simulations of time-variable infrared (IR) emission from dust as a consequence of variability of the incident radiation. For that we introduce a generalized treatment for temperature variations in a dusty environment, which…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Sebastian F. Hoenig , Makoto Kishimoto

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…

An integral part of the Unified Model for Active Galactic Nuclei (AGNs) is an axisymmetric obscuring medium, which is commonly depicted as a torus of gas and dust surrounding the central engine. However, a robust, dynamical model of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 S. K. Keating , J. E. Everett , S. C. Gallagher , R. P. Deo

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
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