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Related papers: Slicing the Torus: Obscuring Structures in Quasars

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We quantify the luminosity contribution of active galactic nuclei (AGN) to the 12 $\mu$m, mid-infrared (MIR; 5-38 $\mu$m), and the total IR (5-1000 $\mu$m) emission in the local AGN detected in the all-sky 70-month Swift/Burst Alert…

The fraction of AGN luminosity obscured by dust and re-emitted in the mid-IR is critical for understanding AGN evolution, unification, and parsec-scale AGN physics. For unobscured (Type-1) AGN, where we have a direct view of the accretion…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 E. Lusso , J. F. Hennawi , A. Comastri , G. Zamorani , G. T. Richards , C. Vignali , E. Treister , K. Schawinski , M. Salvato , R. Gilli

Context: Most active galactic nuclei (AGN) are believed to be surrounded by a dusty molecular torus on the parsec scale which is often embedded within a larger circumnuclear disk (CND). AGN are fuelled by the inward transport of material…

We present a multi-frequency study of the ultraluminous infrared galaxy (ULIRG) IRAS 00183-7111 (z=0.327), selected from the Spoon diagnostic diagram as a highly obscured active galactic nucleus (AGN) candidate. ALMA Cycle 0 millimetre and…

Astrophysics of Galaxies · Physics 2018-09-05 Ilaria Ruffa , Cristian Vignali , Arturo Mignano , Rosita Paladino , Kazushi Iwasawa

The motivation of the "unified model" is to explain the main properties of the large zoo of active galactic nuclei with a single physical object. The discovery of broad permitted lines in the polarized spectrum of type 2 Seyfert galaxies in…

Astrophysics of Galaxies · Physics 2021-02-03 Luigi Spinoglio , Juan Antonio Fernández-Ontiveros

We present a measurement of the star formation properties of a uniform sample of mid-IR selected, unobscured and obscured quasars (QSO1s and QSO2s) in the Bo\"otes survey region. We use an spectral energy distribution (SED) analysis for…

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,…

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…

We present calculations of AGN winds at ~parsec scales, along with the associated obscuration. We take into account the pressure of infrared radiation on dust grains and the interaction of X-rays from a central black hole with hot and cold…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Anton Dorodnitsyn , Timothy Kallman

Quasars are the most luminous of active galactic nuclei (AGN), and are perhaps responsible for quenching star formation in their hosts. The Stripe 82X catalog covers 31.3 deg$^2$ of the Stripe 82 field, of which the 15.6 deg$^2$ covered…

Highly obscured active galactic nuclei (AGN) are common in nearby galaxies, but are difficult to observe beyond the local Universe, where they are expected to significantly contribute to the black hole accretion rate density. Furthermore,…

3C 223 is a radio loud, Type 2 quasar at $z=0.1365$ with an intriguing XMM-Newton spectrum that implicated it as a rare, Compton-thick ($N_{\rm H} \gtrsim 1.25 \times 10^{24}$ cm$^{-2}$) active galactic nucleus (AGN). We obtained…

High Energy Astrophysical Phenomena · Physics 2023-03-01 Stephanie M. LaMassa , Tahir Yaqoob , Panayiotis Tzanavaris , Poshak Gandhi , Timothy Heckman , George Lansbury , Aneta Siemiginowska

We estimate the dust torus cooling timescale once the active galactic nucleus (AGN) is quenched. In a clumpy torus system, once the incoming photons are suppressed, the cooling timescale of one clump from $T_{\rm dust}=1000$ K to several…

Astrophysics of Galaxies · Physics 2017-07-26 Kohei Ichikawa , Ryo Tazaki

X-ray surveys have revealed a new class of active galactic nuclei (AGN) with a very low observed fraction of scattered soft X-rays, f_scat < 0.5%. Based on X-ray modeling these "X-ray new-type", or low observed X-ray scattering…

Astrophysics of Galaxies · Physics 2015-06-17 S. F. Hoenig , P. Gandhi , D. Asmus , R. F. Mushotzky , R. Antonucci , Y. Ueda , K. Ichikawa

We analyze X-ray spectra of heavily obscured (N_H > 10^{24} cm^{-2}) active galaxies obtained with Chandra, concentrating on the iron K alpha fluorescence line. We measure very large equivalent widths in most cases, up to 5 keV in the most…

Astrophysics · Physics 2009-11-07 N. A. Levenson , J. H. Krolik , P. T. Zycki , T. M. Heckman , K. A. Weaver , H. Awaki , Y. Terashima

We analyze the link between active galactic nuclei (AGN) and mid-infrared flux using dust radiative transfer calculations of starbursts realized in hydrodynamical simulations. Focusing on the effects of galaxy dust, we evaluate diagnostics…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-12 Gregory F. Snyder , Christopher C. Hayward , Anna Sajina , Patrik Jonsson , Thomas J. Cox , Lars Hernquist , Philip F. Hopkins , Lin Yan

A significant fraction of the accreting black holes powering high redshift AGN are obscured by large columns of dust and gas. For this reason, luminous type 2 quasars can be efficiently discovered combining hard X-ray and near-infrared…

Astrophysics · Physics 2009-11-10 A. Comastri , F. Fiore , C. Vignali , M. Brusa , F. Civano

One of the most important problems in the study of active galaxies is understanding the detailed geometry, physics, and evolution of the central engines and their environments. The leading models involve an accretion disk and torus…

Astrophysics · Physics 2009-11-10 R. Morganti , L. J. Greenhill , A. B. Peck , D. L. Jones , C. Henkel

Aims: In this paper, we aim to constrain the properties of dust structures in the central first parsecs of Active Galactic Nuclei (AGN). Our goal is to study the required optical depth and composition of different dusty and ionised…

Astrophysics of Galaxies · Physics 2018-05-02 Lucas Grosset , Daniel Rouan , Damien Gratadour , Didier Pelat , Jan Orkisz , Frédéric Marin , René Goosmann

We construct a new sample of 32 obscured active galactic nuclei (AGNs) selected from the Second XMM-Newton Serendipitous Source Catalogue to investigate their multiwavelength properties in relation to the "scattering fraction", the ratio of…