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Related papers: Torus models for obscuration in type 2 AGN

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A sublimation process governs the innermost region of the dusty torus of active galactic nuclei. However, the observed inner radius of the torus is systematically smaller than the expected radius by a factor of ~ 1/3. We show that the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Toshihiro Kawaguchi , Masao Mori

The infrared is a key wavelength regime for probing the dusty, obscured nuclear regions of active galaxies. We present results from an infrared study of 87 nearby Seyfert galaxies using the Spitzer Space Telescope and ground-based…

The presence of an obscuring torus around the nucleus of Seyfert galaxies, as supposed in the popular unification scheme, can strongly modify the X--ray spectrum for both type 1 and 2 Seyfert galaxies. We find that if the torus is Compton…

Astrophysics · Physics 2015-06-24 Gabriele Ghisellini , Francesco Haardt , Giorgio Matt

The role of star-formation driven outflows in the obscuration of the central source in the Active Galactic Nuclei (AGN) is discussed. The outflow from a sub-parsec scale accretion disc is numerically modelled for parameters appropriate to…

Astrophysics · Physics 2008-11-26 Sergei Nayakshin , Jorge Cuadra

To test the dust torus model for active galactic nuclei directly, we study the extent and morphology of the nuclear dust distribution in the Circinus galaxy using high resolution interferometric observations in the mid-infrared with the…

We have recently presented an investigation in full general relativity of the dynamics and gravitational-wave emission from binary neutron stars which inspiral and merge, producing a black hole surrounded by a torus (see arXiv:0804.0594).…

General Relativity and Quantum Cosmology · Physics 2009-06-10 Luca Baiotti , Bruno Giacomazzo , Luciano Rezzolla

Monte Carlo simulation is one of the best tools to study the complex spectra of Compton-thick AGNs and to figure out the relation between their nuclear structures and X-ray spectra. We have simulated X-ray spectra of Compton-thick AGNs…

Astrophysics · Physics 2009-11-13 Shinya Ikeda , Hisamitsu Awaki , Yuichi Terashima

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

AGN are known to have complex X-ray spectra that depend on both the properties of the accreting SMBH (e.g. mass, accretion rate) and the distribution of obscuring material in its vicinity ("torus"). Often however, simple and even unphysical…

High Energy Astrophysical Phenomena · Physics 2014-05-08 J. Buchner , A. Georgakakis , K. Nandra , L. Hsu , C. Rangel , M. Brightman , A. Merloni , M. Salvato , J. Donley , D. Kocevski

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

Heavily obscured Active Galactic Nuclei (AGN), especially Compton-thick sources with line-of-sight column density ($N_{\rm H,los}$) $>$ 10$^{24}$ cm$^{-2}$, are critical to understanding supermassive black hole (SMBH) growth and the origin…

We study the structure and evolution of the hyperaccreting disks and outflows in the gamma ray bursts central engines. The torus around a stellar mass black hole is composed of free nucleons, Helium, electron-positron pairs, and is cooled…

High Energy Astrophysical Phenomena · Physics 2017-01-27 Agnieszka Janiuk , Michal Bejger , Petra Sukova , Szymon Charzynski

In the last decades, several multiwavelength studies have been dedicated to exploring the properties of the obscuring material in active galactic nuclei (AGN). Various models have been developed to describe the structure and distribution of…

Galactic gas-gas collisions involving a turbulent multiphase ISM share common ISM properties: dense extraplanar gas visible in CO, large linewidths (>= 50 km/s), strong mid-infrared H_2 line emission, low star formation activity, and strong…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 B. Vollmer , R. I. Davies

We construct an X-ray spectral model for the clumpy torus in an active galactic nucleus (AGN) using Geant4, which includes the physical processes of the photoelectric effect, Compton scattering, Rayleigh scattering, $\gamma$ conversion,…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Yuan Liu , Xiaobo Li

The spectral energy distributions and infrared (IR) spectra of a sample of obscured AGNs selected in the mid-IR are modeled with recent clumpy torus models to investigate the nature of the sources, the properties of the obscuring matter,…

Astrophysics · Physics 2010-03-19 M. Polletta , D. Weedman , S. Hoenig , C. J. Lonsdale , H. E. Smith , J. Houck

The size and structure of the dusty circumnuclear torus in active galactic nuclei (AGN) can be investigated by analyzing the temporal response of the torus's infrared (IR) dust emission to variations in the AGN ultraviolet/optical…

Astrophysics of Galaxies · Physics 2020-03-02 Triana Almeyda , Andrew Robinson , Michael Richmond , Robert Nikutta , Bryanne McDonough

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…

Astrophysics of Galaxies · Physics 2021-09-08 Almudena Prieto , Jakub Nadolny , Juan A. Fernández-Ontiveros , Mar Mezcua

We report ALMA observations of CO(3-2) emission in a sample of 7 Seyfert/LINER galaxies at the unprecedented spatial resolution of 0.1'' = 4-9 pc. Our aim is to explore the close environment of AGN, and the dynamical structures leading to…

(Abridged) Infrared high-resolution imaging and interferometry have shown that the dust distribution is frequently elongated along the polar direction of an AGN. To explain these findings, we developed a model scenario for the inner ~30 pc…

Astrophysics of Galaxies · Physics 2018-08-15 B. Vollmer , M. Schartmann , L. Burtscher , F. Marin , S. Hoenig , R. Davies , R. Goosmann