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Related papers: Revisiting the Unified Model of Active Galactic Nu…

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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

Observing programs comprising multiple scientific objectives will enhance the productivity of NASA's next UV/Visible mission. Studying active galactic nuclei (AGN) is intrinsically important for understanding how black holes accrete matter,…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-17 Gerard Kriss , Nahum Arav , Anton Koekemoer , Smita Mathur , Bradley M. Peterson , Jennifer E. Scott

(abridged) This paper is the second part of a work investigating the properties of dusty tori in AGN by means of multi-component SED fitting. It focuses on low luminosity, low redshift (z < 0.25) AGN selected among emission line galaxies as…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Evanthia Hatziminaoglou , Jacopo Fritz , Tom Jarrett

Ionization cones and relativistic jets give us one of the most large-scale example of active galactic nuclei (AGN) influence on the surrounding gas environment in galaxies and beyond. The study of ionization cones makes it possible not only…

Astrophysics of Galaxies · Physics 2023-12-05 Alexei V. Moiseev , Aleksandrina A. Smirnova

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

The variability of active galactic nuclei (AGN) has long held the promise of shedding light on their detailed structure, and possibly other astrophysical phenonema. Different emission mechanisms lead to different patterns of variability in…

Astrophysics · Physics 2009-11-07 M. R. S. Hawkins

I review the constraints that X-ray observations impose on the physical properties and the geometrical distribution of cold absorbing gas in nearby obscured Active Galactic Nuclei (AGN), as well as their implications for AGN structure…

Astrophysics · Physics 2007-05-23 Matteo Guainazzi

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,…

Context: We investigate mid-infrared and X-ray properties of the dusty torus invoked in the unification scenario for active galactic nuclei. Aims: We use the relation between mid IR and hard X-ray luminosities to constrain the geometry and…

Astrophysics · Physics 2009-11-13 Hannes Horst , Poshak Gandhi , Alain Smette , Wolfgang J. Duschl

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

We analyse different photometric and spectroscopic properties of active galactic nuclei (AGNs) and quasars (QSOs) selected by their mid-IR power-law and X-ray emission from the COSMOS survey. We use a set of star-forming galaxies as a…

Astrophysics of Galaxies · Physics 2020-03-25 Carlos Guillermo Bornancini , Diego García Lambas

Due to the compactness active galactic nuclei (AGNs) are still unresolved with optical observations. However, structure and physical conditions of the matter in their central parts are especially important to study the processes of the…

Astrophysics of Galaxies · Physics 2020-03-31 Elena Shablovinskaya , Viktor Afanasiev

We present a large sample of infrared-luminous candidate active galactic nuclei (AGNs) that lack X-ray detections in Chandra, XMM-Newton, and NuSTAR fields. We selected all optically detected SDSS sources with redshift measurements,…

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

Since many years we know that dust in the form of the dusty-molecular torus is responsible for the obscuration in active galactic nuclei (AGN) at large viewing angles and thus for the classification of AGN. Recently, we gained some…

Variability studies hold information on otherwise unresolvable regions in Active Galactic Nuclei (AGN). Population studies of large samples likewise have been very productive for our understanding of AGN. These two themes are coming…

High Energy Astrophysical Phenomena · Physics 2016-05-31 Andy Lawrence

Aims: We aim to find torus models that explain the observed high-resolution mid-infrared (MIR) measurements of active galactic nuclei (AGN). Our goal is to determine the general properties of the circumnuclear dusty environments. Methods:…

Astrophysics of Galaxies · Physics 2016-06-29 N. López-Gonzaga , W. Jaffe

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

Outflows from active galactic nuclei (AGN) are one of the fundamental mechanisms by which the central supermassive black hole interacts with its host galaxy. Detected in $\ge 50\%$ of nearby AGN, these outflows have been found to carry…

We review the continuum emission of Active Galactic Nuclei (AGN) over the entire electromagnetic spectrum. After a brief historical introduction, we describe the main spectral properties of unobscured AGN, discussing the selection biases…

Astrophysics · Physics 2016-01-27 G. Risaliti , M. Elvis
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