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Recently, the existence of geometrically thick dust structures in Active Galactic Nuclei (AGN) has been directly proven with the help of mid-infrared interferometry. The observations are consistent with a two-component model made up of a…

Astrophysics · Physics 2009-11-13 M. Schartmann , K. Meisenheimer , H. Klahr , M. Camenzind , S. Wolf , Th. Henning

We present a study of the global properties of Joguet's sample of 65 Seyfert 2 galaxies. We use the population synthesis models of our Paper II to derive `pure' emission-line spectra, and thus explore the statistical properties of the…

X-ray spectroscopy of active galactic nuclei (AGN) offers the opportunity to directly probe the inner regions of the accretion disk. We present the results of our analysis of average AGN XMM-Newton X-ray spectra in the Chandra Deep Field…

High Energy Astrophysical Phenomena · Physics 2014-08-12 S. Falocco , F. J. Carrera , A. Corral , X. Barcons , A. Comastri , R. Gilli , P. Ranalli , C. Vignali , K. Iwasawa , N. Cappelluti , E. Rovilos , I. Georgantopoulos , M. Brusa , F. Vito

For a sample of star forming galaxies in the redshift interval 0.15$<$z$<$0.3, we study how both the relative strength of the AGN infra-red emission, compared to that due to the star formation (SF), and the numerical fraction of AGNs,…

Aims: We present a near-infrared spectral atlas of 47 active galactic nuclei (AGN), of all degrees of activity, in the wavelength interval of 0.8-2.4 microns, including the fluxes of the observed emission lines. We analyze the spectroscopic…

Astrophysics · Physics 2009-11-11 R. Riffel , A. Rodriguez-Ardila , M. G. Pastoriza

Recent evidence for a strong 'hard excess' of flux at energies > 20 keV in some Suzaku observations of type 1 Active Galactic Nuclei (AGN) has motivated an exploratory study of the phenomenon in the local type 1 AGN population. We have…

High Energy Astrophysical Phenomena · Physics 2015-06-12 M. M. Tatum , T. J. Turner , L. Miller , J. N. Reeves

Spectra of extranuclear clouds within the ionization cone of Circinus galaxy are presented and modelled assuming photoionization by the Seyfert 2 nucleus but no preconceived assumption concerning the spectral shape of the ionizing AGN…

Astrophysics · Physics 2007-05-23 E. Oliva , A. Marconi , A. F. M. Moorwood

We aim to study the effect of environment on the presence and fuelling of Active Galactic Nuclei (AGN) in massive galaxy clusters. We explore the use of different AGN detection techniques with the goal of selecting AGN across a broad range…

Astrophysics of Galaxies · Physics 2015-06-05 Alison J. Klesman , Vicki L. Sarajedini

NLTE line formation calculations of FeI in the solar atmosphere are extended to include weak optical lines. Previously established atomic models are used to discriminate between different ways of treating collisional interaction processes.…

Astrophysics · Physics 2009-11-07 T. Gehren , A. J. Korn , J. Shi

In order to perform a more complete census of active galactic nuclei (AGN) in the local Universe, we investigate the use of the HeII~$\lambda 4685$ emission line diagnostic diagram by Shirazi & Brinchmann (2012) in addition to the standard…

Astrophysics of Galaxies · Physics 2017-01-25 Rudolf Bär , Anna K. Weigel , Lia F. Sartori , Kyuseok Oh , Michael Koss , Kevin Schawinski

We describe new efforts to model radio active galactic nuclei (AGN) in a cosmological context using the SAGE semi-analytic galaxy model. Our new method tracks the physical properties of radio jets in massive galaxies, including the…

Astrophysics of Galaxies · Physics 2017-08-09 Mojtaba Raouf , Stanislav S. Shabala , Darren J. Croton , Habib G. Khosroshahi , Maksym Bernyk

We present a study of FeII emission in the near-infrared region (NIR) for 25 active galactic nuclei (AGNs) to obtain information about the excitation mechanisms that power it and the location where it is formed. We employ a NIR FeII…

Astrophysics of Galaxies · Physics 2016-02-17 A. O. M. Marinello , A. Rodriguez-Ardila , A. Garcia-Rissmann , T. A. A. Sigut , A. K. Pradhan

The great power offered by photoionization models of Active Galactic Nuclei (AGN) emission-line regions has long been mitigated by the fact that very little is known about the spectral energy distribution (SED) between the Lyman limit,…

High Energy Astrophysical Phenomena · Physics 2020-05-13 Gary Ferland , Chris Done , Chichuan Jin , Hermine Landt , Martin Ward

We derive a new relation between the metallicity of Seyfert 2 Active Galactic Nuclei (AGNs) and the intensity of the narrow emission-lines ratio $N2O2$=log([N II]$\lambda$6584/[O II]$\lambda$3727). The calibration of this relation was…

Astrophysics of Galaxies · Physics 2017-02-01 C. S. Castro , O. L. Dors , M. V. Cardaci , G. F. Hagele

We present a wide grid of models for the structure and transmission properties of warm absorbers in active galactic nuclei (AGN). Contrary to commonly used constant density models, our absorbing cloud is assumed to be under constant total…

Astrophysics · Physics 2007-05-23 A. Rozanska , R. Goosmann , A. -M. Dumont , B. Czerny

Understanding the connection between active galactic nuclei and star-formation (the AGN-SF connection) is one of the longest standing problems in modern astrophysics. In the age of large Integral Field Unit (IFU) surveys, studies of the…

Astrophysics of Galaxies · Physics 2026-03-11 Aman Chopra , Henry R. M. Zovaro , Rebecca L. Davies

Using 190,000 spectra from the seventeenth data release of the Sloan Digital Sky Survey, we investigate the ultraviolet emission line properties in z=2 quasars. Specifically, we quantify how the shape of CIV 1549A and the equivalent width…

A wide-frequency radio study of Active Galactic Nuclei (AGN) is crucial to evaluate the intervening radiative mechanisms responsible for the observed emission and relate them with the underlying accretion physics. We present wide frequency…

We fit the near-infrared to radio spectral energy distributions of 30 luminous and ultra-luminous infrared galaxies with pure starburst models or models that include both starburst and AGN components to determine important physical…

Astrophysics · Physics 2009-11-13 O. Vega , M. S. Clemens , A. Bressan , G. L. Granato , L. Silva , P. Panuzzo , --

We combine the Herschel Space Observatory PACS and SPIRE photometry with archival WISE photometry to construct the spectral energy distributions (SED) for over 300 local ($z < 0.05$), ultra-hard X-ray (14 - 195 keV) selected active galactic…

Astrophysics of Galaxies · Physics 2017-02-01 T. Taro Shimizu , Richard F. Mushotzky , Marcio Meléndez , Michael J. Koss , Amy J. Barger , Lennox L. Cowie
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