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相关论文: Torus models for obscuration in type 2 AGN

200 篇论文

The putative dusty torus is a key ingredient of the unification scheme of active galactic nuclei (AGN), but its origin remains a mystery. Here we put forward a new physical model to explain how a large number of small dusty gas clumps form…

星系天体物理 · 物理学 2026-03-09 Xinwu Cao , Renyue Cen , Qingwen Wu , Jiancheng Wu

Recently, the MID-infrared Interferometric instrument (MIDI) at the VLTI has shown that dust tori in the two nearby Seyfert galaxies NGC 1068 and the Circinus galaxy are geometrically thick and can be well described by a thin, warm central…

天体物理学 · 物理学 2008-08-06 M. Schartmann , K. Meisenheimer , H. Klahr , M. Camenzind , S. Wolf , Th. Henning

The obscuration observed in active galactic nuclei (AGN) is mainly caused by dust and gas distributed in a torus-like structure surrounding the supermassive black hole (SMBH). However, properties of the obscuring torus of the AGN in X-ray…

星系天体物理 · 物理学 2021-06-09 X. Zhao , S. Marchesi , M. Ajello , D. Cole , Z. Hu , R. Silver , N. Torres-Albà

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…

天体物理学 · 物理学 2009-11-13 Maia Nenkova , Matthew M. Sirocky , Zeljko Ivezic , Moshe Elitzur

According to the unified model of active galactic nuclei (AGNs), a putative dusty torus plays an important role in determining their external appearance. However, very limited information is known about the physical properties of the torus.…

星系天体物理 · 物理学 2018-08-08 Ming-Yang Zhuang , Luis C. Ho , Jinyi Shangguan

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…

The nature of the obscuring material in active galactic nuclei is still uncertain. Although some sources, such as Cygnus A, show evidence for a geometrically thick ``torus'' as originally suggested, recent work on the radiation-driven…

天体物理学 · 物理学 2007-05-23 Philip R. Maloney

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…

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

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…

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…

宇宙学与河外天体物理 · 物理学 2015-06-04 S. K. Keating , J. E. Everett , S. C. Gallagher , R. P. Deo

Near-Eddington radiation from active galactic nuclei (AGNs) has significant dynamical influence on the surrounding dusty gas, plausibly furnishing AGNs with geometrically thick obscuration. We investigate this paradigm with radiative…

星系天体物理 · 物理学 2017-08-21 Chi-Ho Chan , Julian H. Krolik

Quasars and Active Galactic Nuclei (AGNs) are often obscured by dust and gas. It is normally assumed that the obscuration occurs in an oblate "obscuring torus", that begins at the radius at which the most refractive dust can remain solid.…

宇宙学与河外天体物理 · 物理学 2015-06-03 Martin Elvis

We determine the properties of the stellar torus that we showed in a previous paper to result as a product of two merging black holes. If the surrounding stellar cluster is as massive as the binary black hole, the torque acting on the stars…

天体物理学 · 物理学 2009-11-07 Christian Zier , Peter L. Biermann

We describe a complete volume limited sample of nearby active galaxies selected by their 14-195keV luminosity, and outline its rationale for studying the mechanisms regulating gas inflow and outflow. We describe also a complementary sample…

Recent ALMA observations have resolved the obscuring torus in the nearest Sy2 galaxy, NGC1068, in the millimeter band. These observations have confirmed the presence of a geometrically thick torus with an orbital motion of its matter and…

星系天体物理 · 物理学 2020-03-04 E. Yu. Bannikova , N. A. Akerman , A. V. Sergeyev

The primary source of emission of active galactic nuclei (AGN), the accretion disk, is surrounded by an optically and geometrically thick dusty structure ("the so-called dusty torus"). The infrared radiation emitted by the dust is nothing…

星系天体物理 · 物理学 2017-01-13 Marko Stalevski , Claudio Ricci , Yoshihiro Ueda , Paulina Lira , Jacopo Fritz , Maarten Baes

The advent of high-angular resolution IR and sub-mm interferometry allows for spatially-resolved observations of the parsec-scale environment of active galactic nuclei (AGN), commonly referred to as the "torus." While molecular lines show…

星系天体物理 · 物理学 2019-11-06 Sebastian F. Hönig

Magnetic field dragged from the galactic disk along with inflowing gas can provide vertical support to the geometrically and optically thick pc-scale torus in AGN. Using the Soloviev solution initially developed for Tokamaks we derive an…

星系天体物理 · 物理学 2017-06-28 Anton Dorodnitsyn , Tim Kallman

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 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…

宇宙学与河外天体物理 · 物理学 2015-05-14 S. F. Hoenig , M. Kishimoto