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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

Warm gas and dust surround the innermost regions of active galactic nuclei (AGN). They provide the material for accretion onto the super-massive black hole and they are held responsible for the orientation-dependent obscuration of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 K. R. W. Tristram , M. Schartmann , L. Burtscher , K. Meisenheimer , W. Jaffe , M. Kishimoto , S. F. Hönig , G. Weigelt

We use new X-ray data obtained with the Nuclear Spectroscopic Telescope Array (NuSTAR), near-infrared (NIR) fluxes, and mid-infrared (MIR) spectra of a sample of 24 unobscured type 1 active galactic nuclei (AGN) to study the correlation…

Astrophysics of Galaxies · Physics 2017-05-23 I. García-Bernete , C. Ramos Almeida , H. Landt , M. J. Ward , M. Baloković , J. A. Acosta-Pulido

We present new estimates on the fraction of heavily X-ray obscured, Compton-thick (CT) active galactic nuclei (AGNs) out to a redshift of $z \leq$ 0.8. From a sample of 540 AGNs selected by mid-IR (MIR) properties in observed X-ray survey…

Mid-Infrared (IR) silicate dust bands observed in heavily obscured active galactic nuclei (AGNs) include information on the mineralogical properties of silicate dust. We aim to investigate the mineralogical picture of the circumnuclear…

Astrophysics of Galaxies · Physics 2022-12-21 T. Tsuchikawa , H. Kaneda , S. Oyabu , T. Kokusho , H. Kobayashi , Y. Toba

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

[Abridged] We present ISO far-infrared (IR) observations of 21 hard X-ray selected AGN from the HEAO-1 A2 sample. We compare the far-IR to X-ray spectral energy distributions (SEDs) of this sample with various radio and optically selected…

We have combined the CLASXS Chandra survey in Lockman with the Spitzer SWIRE survey data to study the X-ray-infrared connection for AGN. The sample consists of 401 X-ray-sources, of which 306 are detected by Spitzer, and a further 257 AGN…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-02 Michael Rowan-Robinson , Ivan Valtchanov , Kirpal Nandra

We present infrared, optical, and X-ray data of 48 X-ray bright, optically dull AGNs in the COSMOS field. These objects exhibit the X-ray luminosity of an active galactic nucleus (AGN) but lack broad and narrow emission lines in their…

Context. Active galactic nuclei (AGN) of galaxies play an important role in the life and evolution of galaxies due to the impact they exert on certain properties and the evolutionary path of galaxies. It is well known that infrared (IR)…

Astrophysics of Galaxies · Physics 2022-08-24 Carlos G. Bornancini , Gabriel A. Oio , M. Victoria Alonso , Diego García Lambas

Telescopes like Herschel and the Atacama Large Millimeter/submillimeter Array (ALMA) are creating new opportunities to study sources in the far infrared (FIR), a wavelength region dominated by cold dust emission. Probing cold dust in active…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Aden R. Draper , David R. Ballantyne

We present a statistical analysis of the mid-infrared (MIR) spectra of 248 luminous infrared (IR) galaxies (LIRGs) which comprise the Great Observatories All-sky LIRG Survey (GOALS) observed with the Infrared Spectrograph (IRS) on-board the…

Mid-infrared observations are powerful in identifying heavily obscured Active Galactic Nuclei (AGN) which have weak emission in other wavelengths. Data from the Mid-Infrared Instrument (MIRI) onboard JWST provides an excellent opportunity…

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…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Huan Yang , JunXian Wang , Teng Liu

With mid-IR and near-IR long-baseline interferometers, we are now mapping the radial distribution of the dusty accreting material in AGNs at sub-pc scales. We currently focus on Type 1 AGNs, where the innermost region is unobscured and its…

Dust plays a central role in the unification theory of active galactic nuclei (AGNs). However, little is known about the nature (e.g., size, composition) of the dust which forms a torus around the AGN. In this Letter we report a systematic…

Astrophysics of Galaxies · Physics 2015-06-22 Jianwei Lyu , Lei Hao , Aigen Li

We analyze the Spitzer spectra of 140 active galactic nuclei (AGN) detected in the hard X-rays (14-195 keV) by the Burst Alert Telescope (BAT) on board Swift. This sample allows us to probe several orders of magnitude in black hole masses…

We conduct for the first time a theoretical investigation of the mid-infrared spectral energy distribution (SED) produced by dust heated by an active galactic nucleus (AGN) and an extreme starburst. These models employ an integrated…

Astrophysics of Galaxies · Physics 2018-05-16 Shobita Satyapal , Nicholas P. Abel , Nathan J. Secrest

Using the Far Ultraviolet Spectroscopic Explorer (FUSE) we have obtained 87 spectra of 57 low-redshift (z<0.15) active galactic nuclei (AGN). This sample comprises 53 Type 1 AGN and 4 Type 2. All the Type 1 objects show broad O VI 1034…

Astrophysics · Physics 2017-08-23 Gerard A. Kriss , the FUSE AGN Working Group

A parsec-scale dusty torus is thought to be the cause of Active Galactic Nuclei (AGN) dichotomy in the 1/2 types, narrow/broad emission lines. In a previous work, on the basis of parsec-scale resolution infrared / optical dust maps it was…

Astrophysics of Galaxies · Physics 2021-09-08 Almudena Prieto , Jakub Nadolny , Juan A. Fernández-Ontiveros , Mar Mezcua