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相关论文: The AGN Obscuring Torus -- End of the "Doughnut" P…

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We present a statistical analysis of the properties of the obscuring material around active galactic nuclei (AGN). This study represents the first of its kind for an ultra-hard X-ray (14-195keV; Swift/BAT) volume-limited (DL<40 Mpc) sample…

Dedicated searches generally find a decreasing fraction of obscured Active Galactic Nuclei (AGN) with increasing AGN luminosity. This has often been interpreted as evidence for a decrease of the covering factor of the AGN torus with…

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…

We considered the evolution of a self-gravitating clumpy torus in the gravitational field of the central mass of an active galactic nucleus (AGN) in the framework of the N-body problem. The initial conditions take into account winds with…

星系天体物理 · 物理学 2018-03-06 Elena Yu. Bannikova , Alexey V. Sergeyev

We propose a plausible mechanism to explain the formation of the so-called "obscuring tori" around active galactic nuclei (AGNs) based on three-dimensional hydrodynamic simulations including radiative feedback from the central source. The…

星系天体物理 · 物理学 2015-06-11 Keiichi Wada

Multi-scale simulations have made it possible to follow gas inflows onto massive black holes (BHs) from galactic scales to the accretion disk. When sufficient gas is driven towards the BH, gravitational instabilities generically form…

宇宙学与河外天体物理 · 物理学 2012-06-22 Philip F. Hopkins , Christopher C. Hayward , Desika Narayanan , Lars Hernquist

The torus concept as an essential structural component of active galactic nuclei (AGN) is generally accepted. Here, the situation is discussed when the torus "twisting" by the radiation or wind transforms it into a dipole toroidal vortex…

天体物理学 · 物理学 2009-11-13 Elena Yu. Bannikova , Victor M. Kontorovich

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…

天体物理学 · 物理学 2007-05-23 Moshe Elitzur , Maia Nenkova , Zeljko Ivezic

A parsec-scale dusty torus is thought to be the cause of Active Galactic Nuclei (AGN) dichotomy in the 1/2 types, narrow/broad emission lines. In a previous work, on the basis of parsec-scale resolution infrared / optical dust maps it was…

星系天体物理 · 物理学 2021-09-08 Almudena Prieto , Jakub Nadolny , Juan A. Fernández-Ontiveros , Mar Mezcua

Active galactic nuclei (AGN) are generally accepted to be powered by the release of gravitational energy in a compact accretion disk surrounding a massive black hole. Such disks are also necessary to collimate powerful radio jets seen in…

天体物理学 · 物理学 2009-10-30 Jack F. Gallimore , Stefi A. Baum , Christopher P. O'Dea

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…

天体物理学 · 物理学 2009-11-11 E. Ibar , P. Lira

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…

天体物理学 · 物理学 2011-02-11 Maia Nenkova , Matthew M. Sirocky , Robert Nikutta , Zeljko Ivezic , Moshe Elitzur

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,…

天体物理学 · 物理学 2007-05-23 S. F. Hoenig , T. Beckert , K. Ohnaka , G. Weigelt

The key ingredient of active galactic nuclei (AGN) unification, the dusty obscuring torus was so far held responsible for the observed mid-infrared (MIR) emission of AGN. However, the best studied objects with VLTI/MIDI show that instead a…

星系天体物理 · 物理学 2019-09-04 Daniel Asmus

The origin of obscuration in Active Galactic Nuclei (AGN) is still an open debate. In particular, it is unclear what drives the relative contributions to the line-of-sight column densities from galaxy-scale and torus-linked obscuration. The…

One of the most important problems in the study of active galaxies is understanding the detailed geometry, physics, and evolution of the central engines and their environments. The leading models involve an accretion disk and torus…

天体物理学 · 物理学 2009-11-10 R. Morganti , L. J. Greenhill , A. B. Peck , D. L. Jones , C. Henkel

We present observations of the molecular gas in the nuclear environment of three prototypical low luminosity AGN (LLAGN), based on VLT/SINFONI AO-assisted integral-field spectroscopy of H2 1-0 S(1) emission at angular resolutions of ~0.17".…

宇宙学与河外天体物理 · 物理学 2015-06-12 F. Müller-Sánchez , M. A. Prieto , M. Mezcua , R. I. Davies , M. Malkan , M. Elitzur

Recent models for the inner structure of active galactic nuclei (AGN) aim at connecting the outer region of the accretion disk with the broad-line region and dusty torus through a radiatively accelerated, dusty outflow. Such an outflow not…

星系天体物理 · 物理学 2023-09-29 Hermine Landt

We present calculations of AGN winds at ~parsec scales, along with the associated obscuration. We take into account the pressure of infrared radiation on dust grains and the interaction of X-rays from a central black hole with hot and cold…

宇宙学与河外天体物理 · 物理学 2015-06-12 Anton Dorodnitsyn , Timothy Kallman

Since many years we know that dust in the form of the dusty-molecular torus is responsible for the obscuration in active galactic nuclei (AGN) at large viewing angles and thus for the classification of AGN. Recently, we gained some…