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Related papers: Constraining AGN Torus Sizes with Optical and Mid-…

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(abridged) It is generally assumed that the distribution of dust on parsec scales forms a geometrically- and optically-thick entity in the equatorial plane around the accretion disk and broad-line region - dubbed "dust torus" - that emits…

We present observations of NGC 1068 covering the $19.7-53.0$ $\mu$m wavelength range using FORCAST and HAWC+ onboard SOFIA. Using these observations, high-angular resolution infrared (IR) and sub-mm observations, we find an observational…

Context. The putative tori surrounding the accretion disks of active galactic nuclei (AGNs) play a fundamental role in the unification scheme of AGNs. Infrared long-baseline interferometry allows us to study the inner dust distribution in…

We present nuclear spectral energy distributions (SEDs) from 1 to 18 micron of a small sample of nearby, nearly face-on and undisturbed Seyfert galaxies without prominent nuclear dust lanes. These nuclear SEDs probe the central ~35 pc of…

The inner structure of AGNs is expected to change below a certain luminosity limit. The big blue bump, footprint of the accretion disk, is absent for the majority of low-luminosity AGNs (LLAGNs). Moreover, recent simulations suggest that…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 J. A. Fernández-Ontiveros , M. A. Prieto , J. A. Acosta-Pulido , M. Montes

Quasars and Active Galactic Nuclei (AGNs) are often obscured by dust and gas. It is normally assumed that the obscuration occurs in an oblate "obscuring torus", that begins at the radius at which the most refractive dust can remain solid.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Martin Elvis

We present the ultraviolet to submillimetre spectral energy distributions (SEDs) of the HERschel Ultra Luminous Infrared Galaxy Survey (HERUS) sample of 42 local ultraluminous infrared galaxies (ULIRGs) and fit them with a Markov chain…

Stern et al.(2012) presented a study of WISE selection of AGN in the 2 deg^2 COSMOS field, finding that a simple criterion W1-W2>=0.8 provides a highly reliable and complete AGN sample for W2<15.05, where the W1 and W2 passbands are…

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

We assess the systematics and efficiency of an AGN selection method based on mid-infrared (MIR) variability. To this end, we utilize various types of active and inactive galaxies from the Sloan Digital Sky Survey, matching them with…

Astrophysics of Galaxies · Physics 2026-03-27 Shinyu Kim , Minjin Kim , Suyeon Son , Luis C. Ho

Advancements in infrared IR open up the possibility to spatially resolve AGN on the parsec-scale level and study the circumnuclear dust distribution, commonly referred to as the "dust torus", that is held responsible for the type 1/type 2…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Sebastian F. Hoenig , Makoto Kishimoto , Robert Antonucci , Alessandro Marconi , M. Almudena Prieto , Konrad Tristram , Gerd Weigelt

ISO provides a key new far-infrared window through which to observe the multi-wavelength spectral energy distributions (SEDs) of quasars and active galactic nuclei (AGN). It allows us, for the first time, to observe a substantial fraction…

We describe a mid-infrared (MIR) survey of local AGN to be conducted with the CanariCam instrument on the Gran Telescopio Canarias (GTC). We will obtain MIR imaging and spectroscopy of a sample of ~100 AGN covering six orders of magnitude…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-16 A. Alonso-Herrero , C. Packham

Recent mid-infrared (MIR) interferometric observations showed in few active galactic nuclei (AGN) that the bulk of the infrared emission originates from the polar region above the putative torus, where only little dust should be present.…

Astrophysics of Galaxies · Physics 2016-05-25 D. Asmus , S. F. Hönig , P. Gandhi

We present a new approach aimed at constraining the typical size and optical properties of carbon dust grains in Circumstellar envelopes (CSEs) of carbon-rich stars (C-stars) in the Small Magellanic Cloud (SMC). To achieve this goal, we…

Recent observations which resolved the mid-infrared (MIR) emission of nearby active galactic nuclei (AGN), surprisingly revealed that their dust emission appears prominently extended in the polar direction, at odds with the expectations…

Astrophysics of Galaxies · Physics 2019-01-30 Marko Stalevski , Konrad R. W. Tristram , Daniel Asmus

In every proposed unification scheme for Active Galactic Nuclei (AGN), an integral element is the presence of circumnuclear dust arranged in torus-like structures. A crucial model parameter in this context is the covering factor (CF),…

Astrophysics of Galaxies · Physics 2023-11-02 Mateusz Rałowski , Krzysztof Hryniewicz , Agnieszka Pollo , Łukasz Stawarz

We present results on low-resolution mid-infrared (MIR) spectra of 70 infrared-luminous galaxies obtained with the Infrared Spectrograph (IRS) onboard Spitzer. We selected sources from the European Large Area Infrared Survey (ELAIS) with…

We propose a new diagnostic of the ``dusty torus'' model for Seyfert nuclei. Dust grains in the torus are heated by the nuclear continuum, and reradiate mostly in the mid-infrared wavelengths. From the torus geometry, it is predicted that…

Astrophysics · Physics 2009-10-31 Takashi Murayama , Hideaki Mouri , Yoshiaki Taniguchi