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Related papers: Constraining AGN Torus Sizes with Optical and Mid-…

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We report the clearest detection to date of dusty torus signatures in a Weak-Line Radio Galaxy (WLRG). The deep Spitzer InfraRed Spectrograph (IRS) rest-frame mid-infrared (MIR) spectrum of the WLRG PKS 0043-42 (z=0.116) shows a clear…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Cristina Ramos Almeida , Daniel Dicken , Clive Tadhunter , A. Asensio Ramos , K. J. Inskip , M. J. Hardcastle , B. Mingo

We present preliminary results from high resolution (~ 0.05") adaptive optics observations of Cygnus A. The images show a bi-conic structure strongly suggestive of an obscuring torus around a quasar nucleus. A bright (K'=18.5) point source…

Astrophysics · Physics 2016-01-27 Gabriela Canalizo , Claire Max , Robert Antonucci , David Whysong , Alan Stockton , Mark Lacy

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

One of the fundamental concepts in the unified scheme of AGN is that both Seyfert 1 and Seyfert 2 galaxies harbour supermassive nuclear engines blocked from direct view by an optically and geometrically thick torus. If the pressure is…

Astrophysics · Physics 2007-05-23 C. M. Violette Impellizzeri , Alan L. Roy , Christian Henkel

We use photometric and spectroscopic infrared observations obtained with the Spitzer Space Telescope of 12 radio-loud active galactic nuclei (AGN) to investigate the dust geometry. Our approach is to look at the change of the infrared…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Hermine Landt , Catherine L. Buchanan , Pauline Barmby

We report the study of far-IR sizes of submillimeter galaxies (SMGs) in relation to their dust-obscured star formation rate (SFR) and active galactic nuclei (AGN) presence, determined using mid-IR photometry. We determined the…

The Wide-field Infrared Survey Explorer (WISE) has scanned the entire sky with unprecedented sensitivity in four infrared bands, at 3.4, 4.6, 12, and 22 micron. The WISE Point Source Catalog contains more than 560 million objects, among…

Astrophysics of Galaxies · Physics 2015-06-18 Robert Nikutta , Maia Nenkova , Zeljko Ivezic , Nicholas Hunt-Walker , Moshe Elitzur

We investigated the emission of active galactic nuclei dusty tori in the infrared domain, with a focus on the 10 micron silicate feature. We modeled the dusty torus as a clumpy two-phase medium with high-density clumps and a low-density…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-14 Marko Stalevski , Jacopo Fritz , Maarten Baes , Theodoros Nakos , Luka C. Popovic

We combine near-to-mid-IR Spitzer data with shorter wavelength observations (optical to X-rays) to get insights on the properties of a sample of luminous, obscured Active Galactic Nuclei (AGN). We aim at modeling their broad-band Spectral…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 F. Pozzi , C. Vignali , A. Comastri , E. Bellocchi , J. Fritz , C. Gruppioni , M. Mignoli , R. Maiolino , L. Pozzetti , M. Brusa , F. Fiore , G. Zamorani

The properties of the dusty tori in active galactic nuclei (AGNs) have been investigated in detail, mainly focusing on the geometry and components; however, the kinematics of the torus is still not clear. The narrow iron K$\alpha$ line at…

High Energy Astrophysical Phenomena · Physics 2017-07-19 Yuan Liu , Xiaobo Li

We present new calculations of the CAT3D clumpy torus models, which now include a more physical dust sublimation model as well as AGN anisotropic emission. These new models allow graphite grains to persist at temperatures higher than the…

We use a sample of 151 local non-blazar AGN selected from the INTEGRAL all-sky hard X-ray survey to investigate if the observed declining trend of the fraction of obscured (i.e. showing X-ray absorption) AGN with increasing luminosity is…

High Energy Astrophysical Phenomena · Physics 2015-10-07 Sergey Sazonov , Eugene Churazov , Roman Krivonos

We present the first systematic investigation of the [NeV] (14um/24um) and [SIII] (18um/33um) infrared line flux ratios, traditionally used to estimate the density of the ionized gas, in a sample of 41 Type 1 and Type 2 active galactic…

Astrophysics · Physics 2009-06-23 R. P. Dudik , J. C. Weingartner , S. Satyapal , J. Fischer , C. C. Dudley , B. O'Halloran

One of the key ingredients of the Unified Model of Active Galactic Nuclei (AGN) is the presence of a torus-like optically thick medium composed by dust and gas around the putative supermassive black hole. However, the structure, size and…

High Energy Astrophysical Phenomena · Physics 2015-05-12 L. Ballo , P. Severgnini , A. Moretti , R. Della Ceca , S. Andreon , A. Caccianiga , V. Braito , S. Campana , C. Vignali

It is widely assumed that long-wavelength infrared (IR) emission from cold dust (T~20-40K) is a reliable tracer of star formation even in the presence of a bright active galactic nucleus (AGN). Based on radiative transfer (RT) models of…

We explore physically self-consistent models of dusty molecular tori in Active Galactic Nuclei (AGN) with the goal of interpreting VLTI observations and fitting high resolution mid-IR spectral energy distributions (SEDs). The input dust…

In this work, we investigate the dependence of the covering factor (CF) of active galactic nuclei (AGNs) (i) on the mid-infrared (MIR) luminosity and (ii) on the redshift. We constructed 12- and 22-micron luminosity functions (LFs) at 0.006…

Dust enshrouded activity can ideally be studied by mid-infrared (MIR) observations. In order to explore the AGN versus star forming origin of the nuclear MIR emission of galaxies, observations of high spatial resolution are required. Here…

The bulk of the stellar growth over cosmic time is dominated by IR luminous galaxies at cosmic noon (z=1-2), many of which harbor a hidden active galactic nucleus (AGN). We use state of the art infrared color diagnostics, combining Spitzer…

Mateos et al. (2012) presented a highly reliable and efficient mid-infrared (MIR) colour-based selection technique for luminous active galactic nuclei (AGN) using the Wide-field Infrared Survey Explorer (WISE) survey. Here we evaluate the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 S. Mateos , A. Alonso-Herrero , F. J. Carrera , A. Blain , P. Severgnini , A. Caccianiga , A. Ruiz