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Related papers: Testing the AGN Paradigm, Part I: a generic SED fo…

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The presence of an obscuring torus around the nucleus of Seyfert galaxies, as supposed in the popular unification scheme, can strongly modify the X--ray spectrum for both type 1 and 2 Seyfert galaxies. We find that if the torus is Compton…

Astrophysics · Physics 2015-06-24 Gabriele Ghisellini , Francesco Haardt , Giorgio Matt

In this paper we discuss the broad-band X-ray characteristics of a complete sample of 36 type 1 AGN, detected by INTEGRAL in the 20-40 keV band above the 5.5sigma level. We present, for all the objects in the sample, the broad-band (1-110…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 M. Molina , L. Bassani , A. Malizia , J. B. Stephen , A. J. Bird , A. J. Dean , F. Panessa , A. De Rosa , R. Landi

In this paper we report on the broadband X-ray properties of a complete sample of 33 absorbed Seyfert galaxies hard X-ray selected with integral. The high quality broadband spectra obtained with both xmm, and integral-IBIS data are well…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-21 A. De Rosa , F. Panessa , L. Bassani , A. Bazzano , A. J. Bird , R. Landi , A. Malizia , M. Molina , P. Ubertini

Over ten mid-infrared (mid-IR) and X-ray models are currently attempting to describe the nuclear obscuring material of active galactic nuclei (AGNs), but many questions remain unresolved. This study aims to determine the physical parameters…

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

The unified model of active galactic nuclei (AGNs) proposes that different AGN optical spectral types are caused by different viewing angles with respect to an obscuring 'torus'. Therefore, this model predicts that type 1 and type 2 AGNs…

Astrophysics of Galaxies · Physics 2019-06-12 Fan Zou , Guang Yang , William N. Brandt , Yongquan Xue

The basic unified model of active galactic nuclei (AGN) invokes an anisotropic obscuring structure, usually referred to as a torus, to explain AGN obscuration as an angle-dependent effect. We present a new grid of X-ray spectral templates…

High Energy Astrophysical Phenomena · Physics 2018-02-21 M. Baloković , M. Brightman , F. A. Harrison , A. Comastri , C. Ricci , J. Buchner , P. Gandhi , D. Farrah , D. Stern

We present the broad-band soft and hard X-ray spectral analysis of 8 Narrow Line Seyfert 1 galaxies extracted from the IBISCO Sample. The study also focuses on the properties of the NLS1 in our sample in relation to those of the IBISCO…

High Energy Astrophysical Phenomena · Physics 2018-07-17 Manuela Molina , Angela Malizia , Fabrizio Fiore , Chiara Feruglio

We exploit a sample of 80,000 SDSS central galaxies to investigate the effect of AGN feedback on their evolution. We trace the demographics of optically-selected AGN (Seyferts) as a function of their internal properties and environment. We…

Astrophysics of Galaxies · Physics 2023-08-02 V. M. Sampaio , A. Aragón-Salamanca , M. R. Merrifield , R. R. de Carvalho , S. Zhou , I. Ferreras

The Unification Model of AGN suggests that all AGN galaxies should exhibit similar line ratios in their spectra. NGC 5548, a Seyfert I, underwent obscuration -- similar to naturally obscured Seyfert II galaxies -- due to an outflowing…

Astrophysics of Galaxies · Physics 2025-08-19 Divya Patel , Maryam Dehghanian , Gary Ferland

The detection of X-ray emission constitutes a reliable and efficient tool for the selection of Active Galactic Nuclei (AGNs), although it may be biased against the most heavily absorbed AGNs. Simple mid-IR broad-band selection criteria…

Astrophysics of Galaxies · Physics 2020-05-06 E. Pouliasis , G. Mountrichas , I. Georgantopoulos , A. Ruiz , M. Yang , A. Z. Bonanos

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

High-resolution X-ray spectroscopy with XRISM gives an unprecedented view of the ``central engine'' in active galactic nuclei, providing unique insights into black hole accretion and feedback. We present an analysis of the first…

We present the results of X-ray spectral analysis of 22 active galactic nuclei (AGNs) with a small scattering fraction selected from the Second XMM-Newton Serendipitous Source Catalogue using hardness ratios. They are candidates of buried…

Astrophysics of Galaxies · Physics 2014-11-20 Kazuhisa Noguchi , Yuichi Terashima , Hisamitsu Awaki

In unified models, different types of active galaxy nuclei correspond to a single class of objects, where their observed differences are solely due to the different orientations of the obscuring material around the central inner regions.…

Astrophysics of Galaxies · Physics 2017-09-06 Carlos Guillermo Bornancini , Mónica Silvia Taormina , Diego García Lambas

The narrow Fe K$\alpha$ line is one of the main signatures of the reprocessing of X-ray radiation from the material surrounding supermassive black holes, and it has been found to be omnipresent in the X-ray spectra of active galactic nuclei…

Astrophysics of Galaxies · Physics 2015-06-19 Claudio Ricci , Yoshihiro Ueda , Stephane Paltani , Kohei Ichikawa , Poshak Gandhi , Hisamitsu Awaki

In this study, we utilize a sample of 338 galaxies within the redshift range of $\rm 0.02<z<0.1$, drawn from the Sloan Digital Sky Survey (SDSS), for which there are available classifications, based on their emission line ratios. We,…

Astrophysics of Galaxies · Physics 2024-08-07 G. Mountrichas , A. Ruiz , I. Georgantopoulos , E. Pouliasis , A. Akylas , E. Drigga

We report on time-dependent axisymmetric simulations of an X-ray excited flow from a parsec-scale, rotating, cold torus around an active galactic nucleus. Our simulations account for radiative heating and cooling and radiation pressure…

Astrophysics · Physics 2009-11-13 A. Dorodnitsyn , T. Kallman , D. Proga

Understanding black hole-galaxy co-evolution and the role of AGN feedback requires complete AGN samples, including heavily obscured systems. In this work, we present the first UV line-selected ([Nev]3426 and CIV1549) sample of obscured AGN…

The mid-infrared to ultraviolet (0.1 -- 10 $\mu m$) spectral energy distribution (SED) shapes of 407 X-ray-selected radio-quiet type 1 AGN in the wide-field ``Cosmic Evolution Survey" (COSMOS) have been studied for signs of evolution. For a…

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