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Related papers: Evidence for Obscured broad \oiii Components in Ty…

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The deep X-ray, optical, and far-infrared fields that constitute GOODS are sensitive to obscured AGN (N_H>10^{22} cm^{-2}) at the quasar epoch (z~2-3), as well as to unobscured AGN as distant as z~7. Luminous X-ray emission is a sign of…

The dusty environments (= "dust tori'') of AGN are now in reach of observations. Following our paper I on ground-based mid-IR spectro-photometry (H\"onig et al. 2010), we present an upgrade to our radiative transfer model of 3-dimensional…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 S. F. Hoenig , M. Kishimoto

The CGM around unobscured AGN has received much attention in recent years. Comparatively, nebulae associated with obscured AGN are less studied. Here, we simulate the Ly$\alpha$, H$\alpha$, and HeII nebulae around the two types of AGN at…

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

Type 2 AGNs with intrinsically weak broad emission lines (BELs) would be exceptions to the unified model. After examining a number of proposed candidates critically, we find that the sample is contaminated significantly by objects with BELs…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-14 Yong Shi , George H. Rieke , Paul Smith , Jane Rigby , Dean Hines , Jennifer Donley , Gary Schmidt , Aleksandar M. Diamond-Stanic

The properties of the absorption in type 2, narrow line AGNs are reviewed by focusing on the X-ray indicators. I discuss the properties of the cold absorbing medium (the putative torus) and of the reprocessed components, as well as their…

Astrophysics · Physics 2009-10-31 R. Maiolino

Obscuration in active galactic nuclei (AGN) provides insights into the material surrounding the central engine. Compton-thick AGN (CTAGN), characterized by a column density of $N_{\mathrm{H}} \geq 1.5 \times 10^{24} \ \mathrm{cm}^{-2}$, are…

Astrophysics of Galaxies · Physics 2025-04-03 M. L. H. Musa , Z. Z. Abidin , A. Annuar , D. A. A. Lee

(Abridged) Approximately 1% of low redshift (z<0.3) optically-selected type 2 AGNs show a double-peaked [OIII] narrow emission line profile in their spatially-integrated spectra. Such features are usually interpreted as due either to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Yue Shen , Xin Liu , Jenny E. Greene , Michael A. Strauss

[Abridged]The strong asymmetry in the optical [O III]$\lambda$5007 emission line is one of the best signatures of AGN-driven warm (~10$^4$ K) ionized gas outflows on host galaxy scales. While large spectroscopic surveys like SDSS have…

Using a simple unification model for AGN, with a fixed ratio of obscured to unobscured AGN of 3:1, we explain the X-ray, optical and infrared properties of the X-ray sources in the GOODS fields. That is, the GOODS data are consistent with…

Astrophysics · Physics 2007-05-23 Ezequiel Treister , C. M. Urry , Jeff Van Duyne , the GOODS AGN Team

The origin of obscuration in Active Galactic Nuclei (AGN) is still a matter of contention. It is unclear whether obscured AGN are primarily due to line-of-sight effects, a transitory, dust-enshrouded phase in galaxy evolution, or a…

In this manuscript, we recheck the spectroscopic properties of SDSS J134733.36+121724.27 (4C+12.50), confirming the presence of the double-peaked [O~{\sc iii}]$\lambda\lambda4959,5007$\AA\ doublet and a broad H$\alpha$. The former likely…

Astrophysics of Galaxies · Physics 2025-11-11 PeiZhen Cheng , XingQian Chen , GuiLin Liao , Qi Zheng , Ying Gu , MuLin Chen , XueGuang Zhang

A cornerstone of AGN unification schemes is the presence of an optically and geometrically thick dust torus. It provides the obscuration to explain the difference between type 1 and type 2 AGN. We investigate the influence of the dust…

Astrophysics · Physics 2007-09-24 Sebastian F. Hoenig , Thomas Beckert

Type 1 active galactic nuclei display broad emission lines, regarded as arising from photoionized gas moving in the gravitational potential of a supermassive black hole. The origin of this broad-line region gas is unresolved so far,…

Astrophysics of Galaxies · Physics 2017-10-11 Jian-Min Wang , Pu Du , Michael S. Brotherton , Chen Hu , Yu-Yang Songsheng , Yan-Rong Li , Yong Shi , Zhi-Xiang Zhang

We report the discovery of two sources at z=3.867 and z=3.427 that exhibit powerful starburst and AGN activities. They benefit from data from radio to X rays from the CFHTLS-D1/SWIRE/XMDS surveys. Follow-up optical and near-infrared…

Most Active Galactic Nuclei (AGN) are `obscured', i.e. the nucleus is hiding behind a screen of absorbing material. The advantage of having the nucleus obscured is to make easier the observations of those emission components which originate…

Astrophysics · Physics 2009-11-07 G. Matt

The key ingredient of active galactic nuclei (AGN) unification, the dusty obscuring torus was so far held responsible for the observed mid-infrared (MIR) emission of AGN. However, the best studied objects with VLTI/MIDI show that instead a…

Astrophysics of Galaxies · Physics 2019-09-04 Daniel Asmus

AGN are known to have complex X-ray spectra that depend on both the properties of the accreting SMBH (e.g. mass, accretion rate) and the distribution of obscuring material in its vicinity ("torus"). Often however, simple and even unphysical…

High Energy Astrophysical Phenomena · Physics 2014-05-08 J. Buchner , A. Georgakakis , K. Nandra , L. Hsu , C. Rangel , M. Brightman , A. Merloni , M. Salvato , J. Donley , D. Kocevski

The Great Observatories Origins Deep Survey (GOODS) combines deep HST and Spitzer imaging with the deepest Chandra/XMM observations to probe obscured AGN at higher redshifts than previous multiwavelength surveys. We present a…

Astrophysics · Physics 2007-05-23 Ezequiel Treister , C. Megan Urry , Paulina Lira

The state of the matter that is obscuring a small circumnuclear region in AGN can be probed by observations of its broad emission lines. Infrared lines are particularly useful since they penetrate significant columns of obscuring matter,…

Astrophysics · Physics 2009-11-07 D. Lutz , R. Maiolino , A. F. M. Moorwood , H. Netzer , S. J. Wagner , E. Sturm , R. Genzel