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Related papers: Modeling optical and UV polarization of AGNs III. …

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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

[abridged] We investigate the effects of various AGN scattering region geometries on the polarized flux. We introduce a new, publicly available Monte Carlo radiative transfer code, Stokes, which models polarization induced by scattering off…

Astrophysics · Physics 2011-01-31 Rene W. Goosmann , C. Martin Gaskell

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…

Astrophysics · Physics 2009-11-13 Maia Nenkova , Matthew M. Sirocky , Zeljko Ivezic , Moshe Elitzur

If the existence of an obscuring circumnuclear region around the innermost regions of active galactic nuclei (AGN) has been observationally proven, its geometry remains highly uncertain. The morphology usually adopted for this region is a…

High Energy Astrophysical Phenomena · Physics 2015-10-08 F. Marin , M. Stalevski

We introduce a new, publicly available Monte Carlo radiative transfer code, STOKES, which has been developed to model polarization induced by scattering off free electrons and dust grains. It can be used in a wide range of astrophysical…

Astrophysics · Physics 2009-11-13 Rene W. Goosmann , C. Martin Gaskell , M. Shoji

Optical observations cannot resolve the structure of active galactic nuclei (AGN), and a unified model for AGN was inferred mostly from indirect methods. Optical reverberation mapping allowed us to constrain the spatial dimension of the…

High Energy Astrophysical Phenomena · Physics 2017-12-05 P. A. Rojas Lobos , R. W. Goosmann , F. Marin , D. Savić

We model the spectropolarimetric signature resulting from the radiative coupling between the innermost parts of active galactic nuclei (AGNs). We use a new public version of STOKES, a Monte Carlo radiative transfer code presented in the…

High Energy Astrophysical Phenomena · Physics 2015-06-11 F. Marin , R. W. Goosmann , C. M. Gaskell , D. Porquet , M. Dovciak

We investigate the emission of active galactic nuclei (AGN) dusty tori in the infrared domain. Following theoretical predictions coming from hydrodynamical simulations, we model the dusty torus as a 3D two-phase medium with high-density…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-29 Marko Stalevski , Jacopo Fritz , Maarten Baes , Theodoros Nakos , Luka C. Popovic

A thermal active galactic nucleus (AGN) consist of a powerful, broad-band continuum source that is surrounded by several reprocessing media with different geometries and compositions. Here we investigate the expected spectropolarimetric…

High Energy Astrophysical Phenomena · Physics 2012-04-05 Frederic Marin , Rene W. Goosmann

In this research note, we start exploring the influence of the narrow line region (NLR) on the optical/UV continuum polarization of active galactic nuclei (AGN). We have upgraded our previous 3-component model of a thermal Seyfert nucleus…

High Energy Astrophysical Phenomena · Physics 2012-10-11 F. Marin , R. W. Goosmann

We discuss the question whether the matter in dusty tori around active galactic nuclei has a smooth or a clumpy structure. Nenkova, Ivezic & Elitzur (2002) have argued that the lack of emission feature in the SEDs of type 1 AGN galaxies…

Astrophysics · Physics 2009-11-10 C. P. Dullemond , I. M. van Bemmel

We have used the STOKES radiative transfer code, to model polarization induced by dust scattering in the polar regions of Active Galactic Nuclei (AGN). We discuss the wavelength-dependence of the spectral intensity and polarization over the…

Astrophysics · Physics 2007-05-23 Rene W. Goosmann , C. Martin Gaskell , M. Shoji

From extensive radiative transfer calculations we find that clumpy torus models with \No \about 5--15 dusty clouds along radial equatorial rays successfully explain AGN infrared observations. The dust has standard Galactic composition, with…

Astrophysics · Physics 2011-02-11 Maia Nenkova , Matthew M. Sirocky , Robert Nikutta , Zeljko Ivezic , Moshe Elitzur

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 S. F. Hoenig , M. Kishimoto

We present the results of a systematic, broadband X-ray spectral analysis of nearby active galactic nuclei (AGNs) with the X-ray clumpy torus model (XCLUMPY; Tanimoto et al. 2019). By adding 16 AGNs newly analyzed in this paper, we study…

High Energy Astrophysical Phenomena · Physics 2021-01-20 Shoji Ogawa , Yoshihiro Ueda , Atsushi Tanimoto , Satoshi Yamada

I present polarization modelling of Active Galactic Nuclei in the optical/UV range. The modelling is conducted using the Monte-Carlo radiative transfer code Stokes, which self-consistently models the polarization signature of a complex…

Astrophysics · Physics 2007-12-13 Rene W. Goosmann

In this paper, we try to explain the observed correlation between the covering factor (CF) of hot dust and the properties of active galactic nuclei (AGNs), e.g., the bolometric luminosity ($L_{\rm{bol}}$) and black hole mass…

Astrophysics of Galaxies · Physics 2015-12-09 Jian-Jian He , Yuan Liu , Shuang-Nan Zhang

According to the standard paradigm, the strong and compact luminosity of active galactic nuclei (AGN) is due to multi-temperature black body emission originating from an accretion disk formed around a supermassive black hole. This central…

Astrophysics of Galaxies · Physics 2016-10-18 P. Andrea Rojas Lobos , Rene W. Goosmann , Frederic Marin

Tori of Active Galactic Nuclei are made up of a mixture of hot and cold gas, as well as dust. In order to protect the dust grains from destruction by the hot gas as well as by the energetic radiation of the accretion disk, the dust is often…

Astrophysics · Physics 2009-11-13 M. Schartmann , K. Meisenheimer , M. Camenzind , S. Wolf , K. R. W. Tristram , Th. Henning

A cornerstone of AGN unification schemes is the presence of an optically and geometrically thick dust torus. It provides the obscuration to explain the difference between type 1 and type 2 AGN. We investigate the influence of the dust…

Astrophysics · Physics 2007-09-24 Sebastian F. Hoenig , Thomas Beckert
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