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Related papers: Dust in Active Galactic Nuclei: Anomalous Silicate…

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We study the incidence of nuclear obscuration on a complete sample of 1310 AGN selected on the basis of their rest-frame 2-10 keV X-ray flux from the XMM-COSMOS survey, in the redshift range 0.3<z<3.5. We classify the AGN as obscured or…

We report optical extinction properties of dust for a sample of 26 early-type galaxies based on the analysis of their multicolour CCD observations. The wavelength dependence of dust extinction for these galaxies is determined and the…

Astrophysics · Physics 2007-05-23 M. K. Patil , S. K. Pandey , D. K. Sahu , A. K. Kembhavi

X-ray emission detection in a galaxy is one of the efficient tools for selecting Active Galactic Nuclei (AGNs). However, many X-ray-selected AGNs are not easily selected as AGNs by their optical emission. These galaxies, so-called optically…

Astrophysics of Galaxies · Physics 2022-03-31 Itsna K. Fitriana , Takashi Murayama

A large fraction of the accreting supermassive black hole population is shrouded by copious amounts of gas and dust, particularly in the distant ($z\gtrsim1$) Universe. While much of the obscuration is attributed to a parsec-scale torus,…

A sample of local galaxies for which far infrared and uv fluxes are available is used to estimate the characteristic dust extinction in galaxies and to test whether standard dust properties are plausible. Assuming galaxies can be…

Astrophysics · Physics 2009-11-07 Michael Rowan-Robinson

We characterise the relation between the gas and dust content of the interstellar medium towards young stellar objects in the Orion Nebula Cluster. X-ray observations provide estimates of the absorbing equivalent hydrogen column density N_H…

Solar and Stellar Astrophysics · Physics 2016-08-31 Birgit Hasenberger , Jan Forbrich , Joao Alves , Scott Wolk , Stefan Meingast , Konstantin Getman , Ignazio Pillitteri

We report the first detection of ~10 and ~18 micron silicate dust emissions in a low-luminosity active galactic nucleus (AGN), obtained in Spitzer-IRS 7-37 micron spectroscopy of the Type 1 LINER galaxy NGC3998. Silicate emissions in AGN…

Dust reprocesses the intrinsic radiation of active galactic nuclei (AGNs) to emerge at longer wavelengths. The observed mid-infrared (MIR) luminosity depends fundamentally on the luminosity of the central engine, but in detail it also…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 N. A. Levenson , J. T. Radomski , C. Packham , R. E. Mason , J. J. Schaefer , C. M. Telesco

We present the analysis of infrared HST and Spitzer data for a sample of 13 FRII radio galaxies at 0.03<z<0.11 that are classified as narrow-line radio galaxies (NLRG). In the context of the unified schemes for active galactic nuclei (AGN),…

Astrophysics of Galaxies · Physics 2015-06-18 E. A. Ramírez , C. N. Tadhunter , D. Dicken , M. Rose , D. Axon , W. Sparks , C. Packham

Context. Although heavily obscured active galactic nuclei (AGNs) have been found by many observational studies, the properties of the surrounding dust are poorly understood. Using AKARI/IRC spectroscopy, we discover a new sample of a…

Astrophysics of Galaxies · Physics 2019-07-03 T. Tsuchikawa , H. Kaneda , S. Oyabu , T. Kokusho , K. Morihana , H. Kobayashi , M. Yamagishi , Y. Toba

We derive a mean attenuation curve out to the rest-frame extreme ultraviolet (EUV) for 'BAL dust' - the dust causing the additional extinction of active galactic nuclei (AGNs) with broad absorption lines (BALQSOs). In contrast to the…

Astrophysics of Galaxies · Physics 2024-08-06 C. Martin Gaskell , Jake J. M. Gill , Japneet Singh

We analyze the link between active galactic nuclei (AGN) and mid-infrared flux using dust radiative transfer calculations of starbursts realized in hydrodynamical simulations. Focusing on the effects of galaxy dust, we evaluate diagnostics…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-12 Gregory F. Snyder , Christopher C. Hayward , Anna Sajina , Patrik Jonsson , Thomas J. Cox , Lars Hernquist , Philip F. Hopkins , Lin Yan

We examine the possibility of the active galactic nucleus (AGN) obscuration by dusty gas clouds that spurt out from circumnuclear starburst regions. For the purpose, the dynamical evolution of gas clouds is pursued, including the effects of…

Astrophysics · Physics 2009-11-10 Yasuyuki Watabe , Masayuki Umemura

We present the first systematic investigation of the [NeV] (14um/24um) and [SIII] (18um/33um) infrared line flux ratios, traditionally used to estimate the density of the ionized gas, in a sample of 41 Type 1 and Type 2 active galactic…

Astrophysics · Physics 2009-06-23 R. P. Dudik , J. C. Weingartner , S. Satyapal , J. Fischer , C. C. Dudley , B. O'Halloran

The optical classification of a Seyfert galaxy and whether it is considered X-ray absorbed are often used interchangeably. But there are many borderline cases and also numerous examples where the optical and X-ray classifications appear to…

Physical processes such as re-ignition, enhancement, and fading of active galactic nuclei (AGN) are not entirely understood because the timeline of these events is expected to last many years. However, it is well known that the differences…

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

We investigate why half of X-ray--selected active galactic nuclei (AGN) in deep surveys lack signs of accretion in their optical spectra. The majority of these ``optically--dull'' AGN are no more than 6 times fainter than their host…

Astrophysics · Physics 2011-07-18 J. R. Rigby , G. H. Rieke , J. L. Donley , A. Alonso-Herrero , P. G. Pérez-González

We present a detailed study of the X-ray and optical spectra of the luminous Seyfert galaxy Mrk 1393, which revealed variable partial obscuration of the active nucleus. The X-ray spectra obtained by XMM-Newton and Swift show moderate…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 T. G. Wang , H. Y. Zhou , D. Grupe , W. M. Yuan , X. B. Dong , H. L. Lu

We combine two approaches to isolate the AGN luminosity at near-infrared wavelengths and relate the near-IR pure AGN luminosity to other tracers of the AGN. Using integral-field spectroscopic data of an archival sample of 51 local AGNs, we…