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Related papers: Inferring the morphology of AGN torus using X-ray …

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We present X-ray bolometric correction factors, $\kappa_{Bol}$ ($\equiv L_{Bol}/L_X$), for Compton-thick (CT) active galactic nuclei (AGN) with the aim of testing AGN torus models, probing orientation effects, and estimating the bolometric…

This review describes recent developments related to the unified model of active galactic nuclei (AGN). It focuses on new ideas about the origin and properties of the central obscurer (torus), and the connection with its surrounding. The…

Astrophysics of Galaxies · Physics 2015-09-23 Hagai Netzer

In modeling the X-ray spectra of active galactic nuclei (AGNs), the inclination angle is a parameter that can play an important role in analyzing the X-ray spectra of AGN, but it has never been studied in detail. We present a broadband…

Astrophysics of Galaxies · Physics 2020-05-13 X. Zhao , S. Marchesi , M. Ajello , M. balokovic , T. Fischer

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

We present the systematic broadband X-ray spectral analysis of 52 Compton-thick ($24 \leq \log N_{\mathrm{H}}^{\mathrm{LOS}}/\mathrm{cm}^{-2}$) active galactic nucleus (CTAGN) candidates selected by the Swift/BAT all-sky hard X-ray survey…

High Energy Astrophysical Phenomena · Physics 2022-06-29 Atsushi Tanimoto , Yoshihiro Ueda , Hirokazu Odaka , Satoshi Yamada , Claudio Ricci

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

We present an X-ray spectral analysis of 126 galaxies of the 12 micron galaxy sample. We pay particular attention to Compton thick AGN with the help of new spectral fitting models that we have produced, which are based on Monte-Carlo…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Murray Brightman , Kirpal Nandra

We describe improved modelling of the emission by dust in a toroidal--like structure heated by a central illuminating source within Active Galactic Nuclei (AGN). We chose a simple but realistic torus geometry, a flared disc, and a dust…

Astrophysics · Physics 2009-11-13 J. Fritz , A. Franceschini , E. Hatziminaoglou

The all-sky hard X-ray survey performed by Swift/BAT allowed the detection of many heavily obscured Compton-thick AGN. In our previous work, we have identified more than 50 candidate Compton-thick AGN in the local Universe, corresponding to…

Astrophysics of Galaxies · Physics 2019-01-09 I. Georgantopoulos , A. Akylas

Dedicated searches generally find a decreasing fraction of obscured Active Galactic Nuclei (AGN) with increasing AGN luminosity. This has often been interpreted as evidence for a decrease of the covering factor of the AGN torus with…

High Energy Astrophysical Phenomena · Physics 2017-05-31 S. Mateos , F. J. Carrera , X. Barcons , A. Alonso-Herrero , A. Hernán-Caballero , M. Page , C. Ramos Almeida , A. Caccianiga , T. Miyaji , A. Blain

We present the distributions of geometrical covering factors of active galactic nuclei (AGNs) dusty tori (f2) using an X-ray selected complete sample of 227 AGN drawn from the Bright Ultra-hard XMM-Newton Survey. The AGN have z from 0.05 to…

A joint XMM-Newton and NuSTAR observation was conducted for the bright, local Seyfert 1.9 galaxy, NGC 1194. The hard spectral form of this AGN was modeled using the toroidal reprocessor MYTORUS. The decoupled model form provides a good…

High Energy Astrophysical Phenomena · Physics 2020-09-09 T. J. Turner , J. N. Reeves , V. Braito , T. Yaqoob , S. B. Kraemer , P. Severgnini

We present the broad-band X-ray spectral analysis (0.6-50 keV) of seven Compton-Thick active galactic nuclei (CT-AGN; line-of-sight, l.o.s., column density $>10^{24}$ cm$^{-2}$) candidates selected from the Swift-BAT 100-month catalog,…

Obscuration of the innermost parts of active galactic nuclei (AGN) is observed in the majority of the population both in the nearby universe and at high redshift. However, the nature of the structures causing obscuration, especially in…

High Energy Astrophysical Phenomena · Physics 2021-09-07 M. Baloković , S. E. Cabral , L. Brenneman , C. M. Urry

We present a statistical analysis of the properties of the obscuring material around active galactic nuclei (AGN). This study represents the first of its kind for an ultra-hard X-ray (14-195keV; Swift/BAT) volume-limited (DL<40 Mpc) sample…

We perform X-ray spectral analyses to derive characteristics (e.g., column density, X-ray luminosity) of $\approx$10,200 active galactic nuclei (AGNs) in the XMM-Spitzer Extragalactic Representative Volume Survey (XMM-SERVS), which was…

An interesting feature in active galactic nuclei (AGN) accreting at low rate is the weakness of the reflection features in their X-ray spectra, which can result from the gradual disappearance of the torus with decreasing accretion rates. It…

The X-ray spectra of many active galactic nuclei (AGN) exhibit a `soft excess' below 1keV, whose physical origin remains unclear. Diverse models have been suggested to account for it, including ionised reflection of X-rays from the inner…

X-ray spectroscopy of active galactic nuclei (AGN) reveals key information about circumnuclear geometry. Many AGN show a narrow Fe K-alpha line at 6.4 keV and associated Compton-scattered continua, produced by primary continuum scattering…

Astrophysics of Galaxies · Physics 2025-12-25 Ingrid Vanessa Daza-Perilla , Panayiotis Tzanavaris , V. Madurga-Favieres , M. Yukita , A. Ptak , T. Yaqoob

The hard X-ray emission of active galactic nuclei (AGN), and in particular, the reflection component, is shaped by the innermost and outer regions of the galactic nucleus. Our main goal is to investigate the variation of the Compton hump…

Astrophysics of Galaxies · Physics 2019-07-05 Christos Panagiotou , Roland Walter