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相关论文: Constraining AGN Torus Sizes with Optical and Mid-…

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The improvement of the calibration relation for determining the size of the broad-line region from the observed optical luminosity of active galactic nuclei (AGN) is a necessary task to study fundamental parameters of distant AGNs such as…

In the center of active galactic nuclei (AGN), the dusty torus absorb the radiation from the central engine and re-emit in mid-infrared (MIR). Observations have detected moderate anisotropy in the dust MIR emission, in the way that type 1…

高能天体物理现象 · 物理学 2015-06-23 Huan Yang , JunXian Wang , Teng Liu

Obscured AGNs provide an opportunity to study the material surrounding the central engine. Geometric and physical constraints on the absorber can be deduced from the reprocessed AGN emission. In particular, the obscuring gas may reprocess…

高能天体物理现象 · 物理学 2015-06-23 Raj Gohil , David R. Ballantyne

A simple, model-independent method to quantify the stochastic variability of active galactic nuclei (AGNs) is the structure function (SF) analysis. If the SF for the timescales shorter than the decorrelation timescale $\tau$ is a single…

星系天体物理 · 物理学 2017-02-08 Szymon Kozłowski

We have developed the dynamical model of a clumpy torus in an active galactic nucleus (AGN) and compared to recent ALMA observations. We present $N$-body simulations of a torus in the field of a supermassive black hole (SMBH), made of up to…

We propose and demonstrate an experimental method to measure by absorption imaging the size and local column density of a cloud of atoms, even when its smallest dimension is smaller than the resolution of the imaging system. To do this, we…

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…

Multi-scale simulations have made it possible to follow gas inflows onto massive black holes (BHs) from galactic scales to the accretion disk. When sufficient gas is driven towards the BH, gravitational instabilities generically form…

宇宙学与河外天体物理 · 物理学 2012-06-22 Philip F. Hopkins , Christopher C. Hayward , Desika Narayanan , Lars Hernquist

Since a large fraction of active galactic nuclei (AGN) is missed in common UV-excess surveys and is even hard to find in radio, near-IR and X-ray surveys, we have used a new AGN selection technique which is expected to be not affected by…

We construct a new sample of 32 obscured active galactic nuclei (AGNs) selected from the Second XMM-Newton Serendipitous Source Catalogue to investigate their multiwavelength properties in relation to the "scattering fraction", the ratio of…

The broad band spectra of two Swift/BAT AGNs obtained from Suzaku follow-up observations are studied: NGC 612 and NGC 3081. Fitting with standard models, we find that both sources show similar spectra characterized by a heavy absorption…

宇宙学与河外天体物理 · 物理学 2015-05-20 Satoshi Eguchi , Yoshihiro Ueda , Hisamitsu Awaki , James Aird , Yuichi Terashima , Richard Mushotzky

We studied the circumnuclear MIR emission in a sample of 19 local active galactic nuclei (AGN) with high spatial resolution spectra using T-ReCS (Gemini) and CanariCam (GTC), together with IRS/Spitzer observations. We measured the flux and…

We present a highly complete and reliable mid-infrared (MIR) colour selection of luminous AGN candidates using the 3.4, 4.6, and 12 um bands of the WISE survey. The MIR colour wedge was defined using the wide-angle Bright Ultra-Hard…

宇宙学与河外天体物理 · 物理学 2015-06-11 S. Mateos , A. Alonso-Herrero , F. J. Carrera , A. Blain , M. G. Watson , X. Barcons , V. Braito , P. Severgnini , J. L. Donley , D. Stern

Unified schemes of active galactic nuclei (AGN) require an obscuring dusty torus around the central engine. The compact sizes (only a few pc) determined in recent high-resolution observations require that the obscuring matter be clumpy and…

天体物理学 · 物理学 2011-02-11 Moshe Elitzur , Isaac Shlosman

We report herschel observations of 100 very luminous, optically selected AGNs at z=2-3.5 with log(LUV)(erg/sec)> 46.5, where LUV=L1350A. The distribution in LUV is similar to the general distribution of SDSS AGNs in this redshift and…

星系天体物理 · 物理学 2016-03-23 Hagai Netzer , Caterina Lani , Raanan Nordon , Benny Trakhtenbrot , Paulina Lira , Ohad Shemmer

We present 2.5-11 micron spectrophotometric & imaging ISO observations of 28 Sf1, 29 Sf2 & 1 normal galaxy. The Sf1 & Sf2 MIR spectra are statistically different: Sf1 have a strong power-law continuum of index -0.84+/-0.24 & weak PAH…

天体物理学 · 物理学 2007-05-23 J. Clavel , B. Schulz , B. Altieri , P. Barr , P. Claes , A. Heras , K. Leech , L. Metcalfe , A. Salama

We explore the correlation between morphological types and mid-infrared (MIR) properties of an optically flux-limited sample of 154 galaxies from the Forth Data Release (DR4) of Sloan Digital Sky Survey (SDSS), cross-correlated with Spitzer…

天体物理学 · 物理学 2009-11-13 Haining Li , Hong Wu , Chen Cao , Yinan Zhu

In the last decades, several multiwavelength studies have been dedicated to exploring the properties of the obscuring material in active galactic nuclei (AGN). Various models have been developed to describe the structure and distribution of…

We present mid-infrared (MIR) observations of the Seyfert 1 galaxy NGC 4151 using the Large Binocular Telescope Interferometer (LBTI). We took open-loop Fizeau images with 66-104 mas (5.8-9.1 pc) resolution in the N-band (at $8.7$ and…