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Related papers: Covering factor of the dust-driven broad-line regi…

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We use the Balmer decrements of the broad-line regions (BLRs) and narrow-line regions (NLRs) of active galactic nuclei (AGNs) as reddening indicators to investigate the location of the dust for four samples of AGNs with reliable estimates…

Astrophysics of Galaxies · Physics 2016-09-07 Clio Z. P. Heard , C. Martin Gaskell

It has been known for 20 years that the absorbing gas in broad absorption line quasars does not completely cover the continuum emission region, and that partial covering must be accounted for to accurately measure the column density of the…

Galactic outflows are now commonly observed in starburst and active galactic nuclei (AGN) host galaxies. Yet, there is no clear consensus on their physical driving mechanism(s). We have previously shown that AGN radiative feedback, driven…

Astrophysics of Galaxies · Physics 2018-10-17 W. Ishibashi , A. C. Fabian

The most characteristic property of active galaxies, including quasars, are prominent broad emission lines. I will discuss an interesting possibility that dust is responsible for this phenomenon. The dust is known to be present in quasars…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Bozena Czerny , Krzysztof Hryniewicz , Janusz Kaluzny , Ishita Maity

This letter presents a revised radiative transfer model for the infrared (IR) emission of active galactic nuclei (AGN). While current models assume that the IR is emitted from a dusty torus in the equatorial plane of the AGN, spatially…

Astrophysics of Galaxies · Physics 2017-04-05 Sebastian F. Hönig , Makoto Kishimoto

We have studied the radio and far-infrared (FIR) emission from 114 galaxies in the 7 nearest clusters (<100 Mpc) with prominent X-ray emission to investigate the impact of the cluster environment on the star formation and AGN activity in…

Astrophysics · Physics 2009-11-10 Naveen A. Reddy , Min S. Yun

Both observational and theoretical evidence point at outflows originating from accretion disks as fundamental ingredients of active galactic nuclei (AGN). These outflows can have more than one component, for example an unbound supersonic…

High Energy Astrophysical Phenomena · Physics 2021-02-03 Margherita Giustini , Daniel Proga

Broad emission lines in active galactic nuclei (AGNs) mainly arise from gas photoionized by continuum radiation from an accretion disk around a central black hole. The shape of the broad-line profile, described by ${\cal D}_{_{\rm…

Astrophysics of Galaxies · Physics 2016-02-17 Pu Du , Jian-Min Wang , Chen Hu , Luis C. Ho , Yan-Rong Li , Jin-Ming Bai

The broad-line region (BLR) disappears in many low-luminosity AGNs, the reason of which is still controversial. The BLRs in AGNs are believed to be associated with the outflows from the accretion disks. Most of the low-luminosity AGNs…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Xinwu Cao

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…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Raj Gohil , David R. Ballantyne

We present the star formation rate (SFR) measurements based on the spectral energy distribution (SED) analysis with new sub-mm fluxes combined with archival multi-wavelength data for a sample of 52 AGN host galaxies at z $<0.2$. We carried…

The radial distribution of dust has been calculated in outflows driven by radiation pressure in which the gas drag is taken into account. It is shown that the dust distribution in the newly discovered candidate disk around BD+31d643 can be…

Astrophysics · Physics 2007-05-23 A. Lecavelier des Etangs , A. Vidal-Madjar , R. Ferlet

We have calculated the radiation field, dust grain temperatures, and far infrared emissivity of numerical models of turbulent molecular clouds. When compared to a uniform cloud of the same mean optical depth, most of the volume inside the…

Astrophysics · Physics 2009-11-10 Thomas Bethell , Ellen Zweibel , Fabian Heitsch , J. S. Mathis

The afterglow emission from a spreading jet expanding in a circumstellar cloud is discussed. Prompt X-ray radiation and a strong UV flash from the reverse shock produced by the interaction of the jet with the cloud may destroy and clear the…

Astrophysics · Physics 2015-06-24 Z. G. Dai , Y. F. Huang , T. Lu

The polarization spectrum, or wavelength dependence of the polarization fraction, of interstellar dust emission provides important insights into the grain alignment mechanism of interstellar dust grains. We investigate the far-infrared…

Mass loss in oxygen-rich asymptotic giant branch (AGB) stars remains poorly understood, as the dust detected around them appears too transparent to drive winds through absorption alone. The current paradigm invokes outflows driven by photon…

We fitted the optical to mid-infrared (MIR) spectral energy distributions (SEDs) of ~15000 type-I, 0.75<z<2, active galactic nuclei (AGNs) in an attempt to constrain the properties of the physical component responsible for the rest-frame…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Rivay Mor , Benny Trakhtenbrot

We have derived the column densities of heavy elements in three gamma-ray burst (GRB) optical transients, associated with the circumburst or interstellar medium (ISM) of the host galaxy. In comparison with the same elements observed in…

Astrophysics · Physics 2009-11-07 S. Savaglio , S. M. Fall , F. Fiore

Accounting for ~20% of the total QSO population, Broad Absorption Line QSOs are still an unsolved problem in the AGN context. They present wide troughs in the UV spectrum, due to material with velocities up to 0.2 c toward the observer. The…

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