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相关论文: Survival of the obscuring torus in the most powerf…

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Compton-thick active galactic nuclei (CT-AGNs), defined by column density $\mathrm{N_H} \geqslant 1.5 \times 10^{24} \ \mathrm{cm}^{-2}$, are so heavily absorbed that their X-ray emission is often feeble, even undetectable by X-ray…

星系天体物理 · 物理学 2026-04-08 Xiaotong Guo , Qiusheng Gu , Guanwen Fang , Shiying Lu , Fen Lyu , Yongyun Chen , Nan Ding , Mengfei Zhang , Xiaoling Yu , Hongtao Wang

We present the X-ray analysis of the most luminous obscured active galactic nuclei (AGN) inside local ultraluminous infrared galaxies (ULIRGs). Our sample consists of ten sources, harbouring AGN components with estimated luminosity in…

宇宙学与河外天体物理 · 物理学 2015-05-27 E. Nardini , G. Risaliti

We present the X-ray spectral analysis of the 1855 extragalactic sources in the Chandra COSMOS-Legacy survey catalog having more than 30 net counts in the 0.5-7 keV band. 38% of the sources are optically classified Type 1 active galactic…

We propose a plausible mechanism to explain the formation of the so-called "obscuring tori" around active galactic nuclei (AGNs) based on three-dimensional hydrodynamic simulations including radiative feedback from the central source. The…

星系天体物理 · 物理学 2015-06-11 Keiichi Wada

The origin of obscuration in Active Galactic Nuclei (AGN) is still an open debate. In particular, it is unclear what drives the relative contributions to the line-of-sight column densities from galaxy-scale and torus-linked obscuration. The…

A large population of heavily obscured, Compton Thick AGNs is predicted by models of galaxy formation, models of Cosmic X-ray Background and by the ``relic'' super-massive black-hole mass function measured from local bulges. However, so far…

Near-Eddington radiation from active galactic nuclei (AGNs) has significant dynamical influence on the surrounding dusty gas, plausibly furnishing AGNs with geometrically thick obscuration. We investigate this paradigm with radiative…

星系天体物理 · 物理学 2017-08-21 Chi-Ho Chan , Julian H. Krolik

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…

宇宙学与河外天体物理 · 物理学 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

X-ray surveys provide the most efficient means for the detection of Active Galactic Nuclei (AGN). However, they face difficulties in detecting the most heavily obscured Compton-thick AGN. The BAT detector on board the Gehrels/Swift mission,…

星系天体物理 · 物理学 2024-12-25 A. Akylas , I. Georgantopoulos , P. Gandhi , P. Boorman , C. L. Greenwell

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…

高能天体物理现象 · 物理学 2018-02-21 M. Baloković , M. Brightman , F. A. Harrison , A. Comastri , C. Ricci , J. Buchner , P. Gandhi , D. Farrah , D. Stern

The majority of active galactic nuclei (AGN) are obscured by large amounts of absorbing material that makes them invisible at many wavelengths. X-rays, given their penetrating power, provide the most secure way for finding these AGN. The…

Compton-thick active galactic nuclei (CT-AGNs), characterized by a significant absorption with column densities of $\mathrm{N_H}\geqslant 1.5\times 10^{24} \ \mathrm{cm}^{-2}$, emit feeble X-ray radiation and are even undetectable by X-ray…

星系天体物理 · 物理学 2025-02-07 Xiaotong Guo , Qiusheng Gu , Guanwen Fang , Yongyun Chen , Nan Ding , Xiaoling Yu , Hongtao Wang

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…

天体物理学 · 物理学 2007-09-24 Sebastian F. Hoenig , Thomas Beckert

Using the X-ray-selected active galactic nuclei (AGN) from the XMM-XXL north survey and the SDSS Baryon Oscillation Spectroscopic Survey (BOSS) spectroscopic follow-up of them, we compare the properties of X-ray unobscured and obscured…

Current X-ray surveys have proved to be essential tools in order to identify and study AGNs across cosmic time. However, there is evidence that the most heavily obscured AGNs are largely missing even in the deepest surveys. The search for…

宇宙学与河外天体物理 · 物理学 2013-06-04 A. Del Moro , D. M. Alexander , J. R. Mullaney , E. Daddi , F. E. Bauer , A. Pope

We used the CLUMPY torus models and a Bayesian approach to fit the infrared spectral energy distributions (SEDs) and ground-based high-angular resolution mid-infrared spectroscopy of 13 nearby Seyfert galaxies. This allowed us to put tight…

This work discusses the broadband X-ray spectral analysis of 11 candidate heavily-obscured active galactic nuclei (AGN) selected based on their infrared and X-ray properties by a recently published machine learning algorithm. This paper is…

Using Spitzer-IRS spectroscopy, we investigate the ubiquity of Active Galactic Nuclei (AGN) in a complete (~94%), volume-limited sample of the most bolometrically-luminous galaxies (L_IR > (0.3-20) x 10^10 L_sun) to D < 15 Mpc. Our analyses…

宇宙学与河外天体物理 · 物理学 2015-05-13 Andy Goulding , Dave Alexander

Most of the optically classified low ionisation narrow emission-line regions (LINERs) nuclei host an active galactic nuclei (AGN). However, how they fit into the unified model (UM) of AGN is still an open question. The aims of this work are…

We constrain the number density and evolution of Compton-thick Active Galactic Nuclei (AGN), and their contribution to the extragalactic X-ray background. In the local Universe we use the wide area surveys from the Swift and INTEGRAL…

宇宙学与河外天体物理 · 物理学 2015-05-14 E. Treister , C. M. Urry , C. Cardamone , S. Virani , K. Schawinski , E. Gawiser