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Related papers: AGN dust tori at low and high luminosities

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In the unification scheme, narrow-lined (type 2) active galactic nuclei (AGN) are intrinsically similar to broad-lined (type 1) AGN with the exception that the line of sight to the broad emission line region and accretion disk is blocked by…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Yu Lu , Ting-Gui Wang , Xiao-Bo Dong , Hong-Yan Zhou

Obscuration of the innermost parts of active galactic nuclei (AGN) is observed in the majority of the population both in the nearby universe and at high redshift. However, the nature of the structures causing obscuration, especially in…

High Energy Astrophysical Phenomena · Physics 2021-09-07 M. Baloković , S. E. Cabral , L. Brenneman , C. M. Urry

The Effective Eddington Limit for dusty gas surrounding AGN is lower than the canonical Eddington limit for hydrogen gas. Previous results from the Swift/BAT 9-month catalogue suggested that in the overwhelming majority of local AGN, the…

High Energy Astrophysical Phenomena · Physics 2015-06-15 R. V. Vasudevan , A. C. Fabian , R. F. Mushotzky , M. Meléndez , L. M. Winter , M. L. Trippe

Obscured AGN represent a significant fraction of the entire AGN population, especially at high redshift (~70% at z=3--5). They are often characterized by the presence of large gas and dust reservoirs that are thought to sustain and possibly…

The detection of dusty winds dominating the infrared emission of AGN on parsec scales has revealed the limitations of traditional radiative transfer models based on a toroidal distribution of dusty gas. A new, more complex, dynamical…

Astrophysics of Galaxies · Physics 2020-07-28 Marta Venanzi , Sebastian Hönig , David Williamson

(Abridged) With infrared interferometry it is possible to resolve the nuclear dust distributions that are commonly associated with the dusty torus in active galactic nuclei (AGN). The Circinus galaxy hosts the closest Seyfert 2 nucleus and…

Astrophysics of Galaxies · Physics 2013-12-18 K. R. W. Tristram , L. Burtscher , W. Jaffe , K. Meisenheimer , S. F. Hönig , M. Kishimoto , M. Schartmann , G. Weigelt

We investigated the gas obscuration and host galaxy properties of active galactic nuclei (AGN) during the peak of cosmic accretion growth of supermassive black holes (SMBHs) at redshift 0.8-1.8 using X-ray detected AGN with mid-infrared and…

Stern et al.(2012) presented a study of WISE selection of AGN in the 2 deg^2 COSMOS field, finding that a simple criterion W1-W2>=0.8 provides a highly reliable and complete AGN sample for W2<15.05, where the W1 and W2 passbands are…

Numerous X-ray spectral models have been developed to model emission reprocessed by the torus of an active galactic nucleus (AGN), e.g., UXCLUMPY, CTORUS, and MYTORUS. They span a range of assumed torus geometries and morphologies-some…

High Energy Astrophysical Phenomena · Physics 2021-12-15 Tathagata Saha , Alex G. Markowitz , Johannes Buchner

Active Galactic Nuclei (AGN) are extremely powerful cosmic objects, driven by accretion of hot gas upon super-massive black holes. The zoo of AGN classes are divided into two major groups, with Type-1 AGN displaying broad Balmer emission…

Context: Active galactic nuclei (AGN) are anisotropic objects surrounded by an optically thick equatorial medium whose true geometry still defy observers. Aims: In this paper, we aim to explore the optical, scattering-induced, polarization…

Astrophysics of Galaxies · Physics 2017-11-15 F. Marin , M. Schartmann

We utilize mid-infrared multi-epoch data from Wide-field Infrared Survey Explorer (WISE) over a $\sim10$-year period in W1 (3.4$\mu$m) and W2 (4.6$\mu$m) bands to investigate the structure of dusty torus in low-redshift ($0.15<z\le 0.4$)…

Astrophysics of Galaxies · Physics 2022-03-14 Suyeon Son , Minjin Kim , Luis C. Ho

A large fraction of the accreting supermassive black hole population is shrouded by copious amounts of gas and dust, particularly in the distant ($z\gtrsim1$) Universe. While much of the obscuration is attributed to a parsec-scale torus,…

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 present an analysis of multi-timescale variability in line-of-sight X-ray absorbing gas as a function of optical classification in a large sample of Seyfert AGN to derive the first X-ray statistical constraints for clumpy-torus models.…

Astrophysics of Galaxies · Physics 2014-02-21 Alex Markowitz , Mirko Krumpe , Robert Nikutta

The presence of an obscuring torus at pc-scale distances from the central black hole is the main ingredient for the Unified Model of Active Galactic Nuclei (AGN), as obscured sources are thought to be seen through this structure. However,…

A fundamental ingredient in the unified model of active galactic nuclei (AGN) is the obscuring torus, whose innermost, hottest region dominates the near infrared (NIR) emission. Characterising the change in the torus properties and its…

In some AGN, nuclear dust lanes connected to kpc-scale dust structures provide all the extinction required to obscure the nucleus, challenging the role of the dusty torus proposed by the Unified Model. In this letter we show the pc-scale…

Astrophysics of Galaxies · Physics 2016-01-13 M. Mezcua , M. A. Prieto , J. A. Fernández-Ontiveros , K. R. W. Tristram

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".…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 F. Müller-Sánchez , M. A. Prieto , M. Mezcua , R. I. Davies , M. Malkan , M. Elitzur

We explore host galaxy properties and environment of a sample of Type 1 and 2 active galactic nuclei (AGN) taken from the COSMOS2015 catalog, within 0.3 $\leq z \leq$ 1.1 selected for their emission in X-rays, optical spectra and SED…

Astrophysics of Galaxies · Physics 2018-07-11 Carlos Guillermo Bornancini , Diego García Lambas