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

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We present observational evidences that dust in the circumnuclear region of AGNs has different properties than in the Galactic diffuse interstellar medium. By comparing the reddening of optical and infrared broad lines and the X-ray…

Astrophysics · Physics 2009-10-31 R. Maiolino , A. Marconi , M. Salvati , G. Risaliti , P. Severgnini , F. La Franca , L. Vanzi

We discuss a clumpy model of obscuring dusty tori around AGN. Cloud-cloud collisions lead to an effective viscosity and a geometrically thick accretion disk, which has the required properties of a torus. Accretion in the combined…

Astrophysics · Physics 2016-08-30 Thomas Beckert , Wolfgang J. Duschl , Bernd Vollmer

Type 2 AGN are by definition nuclei in which the broad-line region and continuum light are hidden at optical/UV wavelengths by dust. Via accurate registration of infrared (IR) Very Large Telescope adaptive optics images with optical…

Astrophysics of Galaxies · Physics 2015-06-19 M. A. Prieto , M. Mezcua , J. A. Fernández-Ontiveros , M. Schartmann

There is evidence for significant evolution in the gaseous and dust properties of galaxies since the era of cosmic noon ($1\lesssim z\lesssim 2.5$). The well known co-evolution of supermassive black holes with their host galaxies suggests a…

Astrophysics of Galaxies · Physics 2025-12-10 Devang H. Liya , David J. Rosario , Matthaios Charidis

We perform X-ray spectral analyses to derive characteristics (e.g., column density, X-ray luminosity) of $\approx$10,200 active galactic nuclei (AGNs) in the XMM-Spitzer Extragalactic Representative Volume Survey (XMM-SERVS), which was…

In modeling the X-ray spectra of active galactic nuclei (AGNs), the inclination angle is a parameter that can play an important role in analyzing the X-ray spectra of AGN, but it has never been studied in detail. We present a broadband…

Astrophysics of Galaxies · Physics 2020-05-13 X. Zhao , S. Marchesi , M. Ajello , M. balokovic , T. Fischer

Unification Models of Active Galactic Nuclei postulate that all the observed differences between Type 1 and Type 2 objects are due to orientation effects with respect to the line-of-sight to the observer. The key ingredient of these models…

Astrophysics of Galaxies · Physics 2015-06-03 Stefano Bianchi , Roberto Maiolino , Guido Risaliti

We present a unification model for a clumpy obscurer in active galactic nuclei (AGN) and investigate the properties of the resulting X-ray spectrum. Our model is constructed to reproduce the column density distribution of the AGN population…

High Energy Astrophysical Phenomena · Physics 2019-09-04 Johannes Buchner , Murray Brightman , Kirpal Nandra , Robert Nikutta , Franz E. Bauer

We present results from the fitting of infrared (IR) spectral energy distributions of 21 active galactic nuclei (AGN) with clumpy torus models. We compiled high spatial resolution ($\sim 0.3$--$0.7$ arcsec) mid-IR $N$-band spectroscopy,…

Dust torus plays the key role in determining active galactic nuclei (AGN) observational appearance. Here, the scenario of accretion regulated central dust torus is tested for the first time in the individual changing-look AGN (CLAGN) SDSS…

Astrophysics of Galaxies · Physics 2026-04-09 Zhang XueGuang

An optically and geometrically thick torus obscures the central engine of Active Galactic Nuclei (AGN) from some lines of sight. From a magnetohydrodynamical framework, the torus can be considered to be a particular region of clouds…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-21 E. Lopez-Rodriguez , C. Packham , S. Young , M. Elitzur , N. A. Levenson , R. E. Mason , C. Ramos Almeida , A. Alonso-Herrero , T. J. Jones , E. Perlman

Using the X-ray-selected active galactic nuclei (AGN) from the XMM-XXL north survey and the SDSS Baryon Oscillation Spectroscopic Survey (BOSS) spectroscopic follow-up of them, we compare the properties of X-ray unobscured and obscured…

(Abridged) We present the results from the X-ray spectral analysis of high-z AGN in the CDFS, making use of the new 4Ms data set and new X-ray spectral models from Brightman & Nandra, which account for Compton scattering and the geometry of…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Murray Brightman , Yoshihiro Ueda

Obscuring circumnuclear dust is a well-established constituent of active galactic nuclei (AGN). Traditionally referred to as the receding dusty torus, its inner radius and angular extension should depend on the photo-ionizing luminosity of…

High Energy Astrophysical Phenomena · Physics 2016-06-15 F. Marin , R. W. Goosmann , P. -O. Petrucci

The nature of the putative torus and the outer geometry of active galactic nuclei (AGN) are still rather unknown and the subject of active research. Improving our understanding of them is crucial for developing a physical picture for the…

Astrophysics of Galaxies · Physics 2021-09-29 Christos Panagiotou , Roland Walter , Stephane Paltani

We briefly review the synergy between X-ray and infrared observations for Active Galactic Nuclei (AGNs) detected in cosmic X-ray surveys, primarily with XMM-Newton, Chandra, and NuSTAR. We focus on two complementary aspects of this…

High Energy Astrophysical Phenomena · Physics 2017-05-10 D. M. Alexander

Unified schemes of active galactic nuclei (AGN) require an obscuring dusty torus around the central source, giving rise to Seyfert 1 line spectrum for pole-on viewing and Seyfert 2 characteristics in edge-on sources. Although the observed…

Astrophysics · Physics 2009-11-07 M. Nenkova , Z. Ivezic , M. Elitzur

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…

Deep extragalactic X-ray surveys, such as the Chandra COSMOS-Legacy field (CCLS), are prone to be biased against active galactic nuclei (AGN) with high column densities due to their lower count rates at a given luminosity. To quantify this…

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…

Astrophysics of Galaxies · Physics 2023-09-29 Hermine Landt
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