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Related papers: AGN dust tori at low and high luminosities

200 papers

We combine near-to-mid-IR Spitzer data with shorter wavelength observations (optical to X-rays) to get insights on the properties of a sample of luminous, obscured Active Galactic Nuclei (AGN). We aim at modeling their broad-band Spectral…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 F. Pozzi , C. Vignali , A. Comastri , E. Bellocchi , J. Fritz , C. Gruppioni , M. Mignoli , R. Maiolino , L. Pozzetti , M. Brusa , F. Fiore , G. Zamorani

Deep surveys of {\em Chandra} and {\em HST} (Hubble Space Telescope) show that active galactic nucleus (AGN) populations are changing with hard X-ray luminosities. This arises an interesting question whether the dusty torus is evolving with…

Astrophysics · Physics 2009-11-11 J. -M. Wang , E. P. Zhang , B. Luo

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

Infrared interferometry of local AGN has revealed a warm (~300K-400K) polar dust structure that cannot be trivially explained by the putative dust torus of the unified model. This led to the development of the disk+wind scenario which…

The recent Spitzer detections of the 9.7 micron Si--O silicate emission in type 1 AGNs provide support for the AGN unification scheme. The properties of the silicate dust are of key importance to understanding the physical, chemical and…

Astrophysics · Physics 2009-11-13 M. P. Li , Q. J. Shi , Aigen Li

The circumnuclear material around Active Galactic Nuclei (AGN) is one of the essential components of the obscuration-based unification model. However, our understanding of the circumnuclear material in terms of its geometrical shape,…

Astrophysics of Galaxies · Physics 2023-04-27 Abhijit Kayal , Veeresh Singh , Claudio Ricci , N. P. S. Mithun , Santosh Vadawale , Gulab Dewangan , Poshak Gandhi

We have combined the CLASXS Chandra survey in Lockman with the Spitzer SWIRE survey data to study the X-ray-infrared connection for AGN. The sample consists of 401 X-ray-sources, of which 306 are detected by Spitzer, and a further 257 AGN…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-02 Michael Rowan-Robinson , Ivan Valtchanov , Kirpal Nandra

Substantial evidence points to dusty, geometrically thick tori obscuring the central engines of active galactic nuclei (AGNs), but so far no mechanism satisfactorily explains why cool dust in the torus remains in a puffy geometry.…

Astrophysics of Galaxies · Physics 2016-07-04 Chi-Ho Chan , Julian H. Krolik

The presence of absorbing gas around the central engine of Active Galactic Nuclei (AGN) is a common feature of these objects. Recent work has looked at the effect of the dust component of the gas, and how it enhances radiation pressure such…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 S. I. Raimundo , A. C. Fabian , F. E. Bauer , D. M. Alexander , W. N. Brandt , B. Luo , R. V. Vasudevan , Y. Q. Xue

We propose a new method to explore the candidate super-Eddington active galactic nuclei (AGNs). We examine the properties of infrared (IR) emission from the inner edge of the dusty torus in AGNs, which are powered by super- or sub-Eddington…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Nozomu Kawakatu , Ken Ohsuga

The geometry of the dust distribution within the inner regions of Active Galactic Nuclei (AGN) is still a debated issue and relates directly with the AGN unified scheme. Traditionally, models discussed in the literature assume one of two…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 A. Feltre , E. Hatziminaoglou , J. Fritz , A. Franceschini

We present mid-IR interferometric observations of 6 type 1 AGNs at multiple baseline lengths of 27--130m, reaching high angular resolutions up to lambda/B~0.02 arcseconds. For two of the targets, we have simultaneous near-IR interferometric…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Makoto Kishimoto , Sebastian F. Hoenig , Robert Antonucci , Florentin Millour , Konrad R. W. Tristram , Gerd Weigelt

We present the analysis of a sample of 35 candidate Compton thick (CT-) active galactic nuclei (AGNs) selected in the nearby Universe (average redshift <z>~0.03) with the Swift-BAT 100-month survey. All sources have available NuSTAR data,…

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)…

The "torus" obscurer of Active Galactic Nuclei (AGN) is poorly understood in terms of its density, substructure and physical mechanisms. Large X-ray surveys provide model boundary constraints, for both Compton-thin and Compton-thick levels…

High Energy Astrophysical Phenomena · Physics 2017-01-11 Johannes Buchner , Franz E. Bauer

Interferometric measurements in the mid-infrared have shown that the sizes of the warm dust distributions in active galactic nuclei are consistent with their scaling with the square root of their luminosity. We carry out a more detailed…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Konrad R. W. Tristram , Marc Schartmann

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…

The unification theory of active galactic nuclei (AGNs) hypothesizes that all AGNs are surrounded by an anisotropic dust torus and are essentially the same objects but viewed from different angles. However, little is known about the dust…

Astrophysics of Galaxies · Physics 2017-01-18 Yanxia Xie , Aigen Li , Lei Hao

Partial dust obscuration in active galactic nuclei (AGN) has been proposed as a potential explanation for some cases of AGN variability. The dust-gas mixture present in AGN tori is accelerated by radiation pressure, leading to the launching…

Astrophysics of Galaxies · Physics 2024-10-08 Nadine H. Soliman , Philip F. Hopkins

We have developed the dynamical model of a clumpy torus in an active galactic nucleus (AGN) and compared to recent ALMA observations. We present $N$-body simulations of a torus in the field of a supermassive black hole (SMBH), made of up to…

Astrophysics of Galaxies · Physics 2021-02-25 E. Yu. Bannikova , A. V. Sergeyev , N. A. Akerman , P. P. Berczik , M. V. Ishchenko , M. Capaccioli , V. S. Akhmetov
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