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Related papers: Constraining Torus Models for AGNs Using X-Ray Obs…

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Variable X-ray absorption has been observed in active galactic nuclei (AGN) on several time scales. Observations allow us to identify the absorber with clouds associated either with the clumpy torus (parsec scales, long timescales) or with…

High Energy Astrophysical Phenomena · Physics 2018-10-18 Mario Sanfrutos , Giovanni Miniutti , Michal Dovčiak , Beatriz Agís-González

In recent years deep X-ray and infrared surveys have provided an efficient way to find accreting supermassive black holes, otherwise known as active galactic nuclei (AGN), in the young universe. Such surveys can, unlike optical surveys,…

Astrophysics · Physics 2007-12-10 C. Megan Urry , E. Treister

This is the second in a series of papers devoted to explore a set of six dusty models of active galactic nuclei (AGN) with available spectral energy distributions (SEDs). These models are the smooth torus by Fritz et al. (2006), the clumpy…

We present a detailed spectral analysis of the brightest Active Galactic Nuclei (AGN) identified in the 7Ms Chandra Deep Field South (CDF-S) survey over a time span of 16 years. Using a model of an intrinsically absorbed power-law plus…

We investigate models for the power supply and broad-band spectral energy distribution (SED) of hyperluminous IR galaxies, recently discovered at high redshifts, in terms of the emission from an active nucleus embedded in a torus-like dusty…

Astrophysics · Physics 2009-10-28 Gian Luigi Granato , Luigi Danese , Alberto Franceschini

We construct the rest-frame 2--10 keV intrinsic X-ray luminosity function of Active Galactic Nuclei (AGNs) from a combination of X-ray surveys from the all-sky Swift BAT survey to the Chandra Deep Field-South. We use ~3200 AGNs in our…

We review some of the main physical and statistical properties of the X-ray absorber in AGNs. In particular, we review the distribution of the absorbing column density inferred from X-ray observations of various AGN samples. We discuss the…

Astrophysics · Physics 2007-05-23 R. Maiolino , G. Risaliti

The presence of obscuring material (or a dusty `torus') in active galactic nuclei (AGN) is central to the unification model for AGN. Two models, the multi-population model for radio sources and the receding torus model, are capable of…

Astrophysics · Physics 2009-11-10 T. G. Arshakian

Two families of models of dusty tori in AGNs (moderately thick and extended versus very thick and compact) are tested against available observations. The confrontation suggests that the former class better explains the IR broad-band spectra…

Astrophysics · Physics 2009-10-30 Gian Luigi Granato , Luigi Danese , Alberto Franceschini

A significant number of active galactic nuclei (AGNs) are observed to be hidden behind dust and gas. The distribution of material around AGNs plays an important role in modeling the cosmic X-ray background (CXB), especially the fraction of…

High Energy Astrophysical Phenomena · Physics 2018-02-28 Raj Gohil , David R. Ballantyne

One of the remaining open issues in the context of the analysis of Active Galactic Nuclei (AGN) is the evidence that nuclear gravitational accretion is often accompanied by a concurrent starburst (SB) activity. What is, in this picture, the…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-22 Anna Feltre

We construct an X-ray spectral model from the clumpy torus in an active galactic nucleus (AGN), designated as "XCLUMPY", utilizing the Monte Carlo simulation for Astrophysics and Cosmology framework (MONACO: Odaka et al. 2011, 2016). The…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Atsushi Tanimoto , Yoshihiro Ueda , Hirokazu Odaka , Toshihiro Kawaguchi , Yasushi Fukazawa , Taiki Kawamuro

The structure of obscuring matter in the environment of active galactic nuclei with associated nuclear starbursts is investigated using 3-D hydrodynamical simulations. Simple analytical estimates suggest that the obscuring matter with…

Astrophysics · Physics 2009-11-07 Keiichi Wada , Colin A. Norman

Coronal-Line Forest Active Galactic Nuclei (CLiF AGN) are characterized by strong, high-ionization lines, which are in contrast to what is found in typical AGNs. Here, we carry out an infrared analysis aimed at understanding the spectral…

Astrophysics of Galaxies · Physics 2023-07-05 F. C. Cerqueira-Campos , A. Rodríguez-Ardila , S. Panda , R. Riffel , L. G. Dahmer-Hahn , M. Marinello

We investigate the radial structure of active galactic nuclei (AGN) dusty tori by forward-modeling mid-infrared (MIR) spectra observed with JWST/MIRI-MRS for a sample of 25 AGN. We develop a physically motivated three dimensional radiative…

Astrophysics of Galaxies · Physics 2026-03-17 Ruiyu Pan , Arkaprabha Sarangi

Recent infrared interferometric observations revealed sub-parsec scale dust distributions around active galactic nuclei (AGNs). Using images of CLUMPY torus models and NGC 1068 as an example, we demonstrate that the near- and mid-infrared…

Astrophysics of Galaxies · Physics 2021-12-22 R. Nikutta , E. Lopez-Rodriguez , K. Ichikawa , N. A. Levenson , C. Packham , S. F. Hönig , A. Alonso-Herrero

The cosmic X-ray background (CXB) is dominated by the obscured and unobscured coronal light of active galactic nuclei (AGN). At energies below 10 keV, the CXB can be well explained by models taking into account the known AGN and the…

High Energy Astrophysical Phenomena · Physics 2025-02-03 Isaiah S. Cox , Núria Torres-Albà , Stefano Marchesi , Peter Boorman , Xiurui Zhao , Ross Silver , Marco Ajello , Indrani Pal

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…

Astrophysics · Physics 2009-11-13 Elena Yu. Bannikova , Victor M. Kontorovich

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

In this paper we report the results of an X-ray monitoring campaign on the heavily obscured Seyfert galaxy Markarian 3 carried out between the fall of 2014 and the spring of 2015 with NuSTAR, Suzaku and XMM-Newton. The hard X-ray spectrum…