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Related papers: Seyfert 2 Galaxies with Spectropolarimetric Observ…

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The origin of the unification model for Active Galactic Nuclei (AGN) was the detection of broad hydrogen recombination lines in the optical polarized spectrum of the Seyfert 2 galaxy (Sy2) NGC 1068. Since then, a search for the hidden…

We have discovered polarized broad emission lines in five type 2 Seyfert galaxies (NGC 424, NGC 591, NGC 2273, NGC 3081, and NGC 4507), establishing that these objects are type 1 Seyferts obscured by dense circumnuclear material. The…

Astrophysics · Physics 2009-10-31 E. C. Moran , A. J. Barth , L. E. Kay , A. V. Filippenko

JHKL'M (1-5 micron) imaging of a sample of Seyfert (Sy) 2 galaxies is presented. We confirm that the 1-2.2 micron nuclear continuum of some Sy 2s is dominated by stellar emission, whereas the continuum emission at longer wavelengths (3-5…

Astrophysics · Physics 2009-10-31 A. Alonso-Herrero , A. C. Quillen , C. Simpson , A. Efstathiou , M. J. Ward

We present an X-ray spectroscopic study of optically selected (SDSS) Seyfert 2 (Sy2) galaxies. The goal is to study the obscuration of Sy2 galaxies beyond the local universe, using good quality X-ray spectra in combination with high S/N…

Infrared, optical and ultraviolet spectropolarimetric observations have proven to be ideal tools for the study of the hidden nuclei of type-2 active galactic nuclei (AGN) and for constraining the composition and morphology of the sub-parsec…

High Energy Astrophysical Phenomena · Physics 2017-11-08 F. Marin , M. Dovciak , F. Muleri , F. F. Kislat , H. S. Krawczynski

We present the Spitzer 10-37um IRS high resolution (R~600) spectroscopic survey of the Seyfert galaxies of the 12 micron Galaxy Sample. The new spectra of 61 galaxies, with those already published, gives us a total of 91 12micron Seyfert…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Silvia Tommasin , Luigi Spinoglio , Matthew A. Malkan , Giovanni Fazio

Using a large sample of 90 Seyfert 2 galaxies (Sy2s) with spectropolarimetric observations, we tested the suggestion that the presence of hidden broad-line regions (HBLRs) in Sy2s is dependent upon the Eddington ratio. The stellar velocity…

Astrophysics · Physics 2008-11-26 W. Bian , Q. Gu

We study 12 Seyfert 1 galaxies with a high level of optical polarization. Optical light emerging from the innermost regions is predominantly scattered in a polar region above the central engine directly in our line of sight. These sources…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-27 Tobias Beuchert , Jörn Wilms , Matthias Kadler , Anna Lia Longinotti , Matteo Guainazzi , Giovanni Miniutti , Ignacio de la Calle

The magnitude-limited catalog of the Southern Sky Redshift Survey (SSRS2), is used to characterize the properties of galaxies hosting Active Galactic Nuclei. Using emission-line ratios, we identify a total of 162 (3%) Seyfert galaxies out…

Astrophysics · Physics 2009-11-10 Marcio A. G. Maia , Rodolfo S. Machado , Christopher N. A. Willmer

A number of studies have shown that the visibility of scattered broad emission lines in Seyfert 2 galaxies is strongly dependent on the IRAS f_60/f_25 flux ratio, where those Seyfert 2s with `warm' IRAS colours show polarised broad line…

Astrophysics · Physics 2009-11-07 S. L. Lumsden , D. M. Alexander

We present spectroscopy of emission lines for 81 Seyfert 1 and 104 Seyfert 2 galaxies in the IRAS 12$\mu$m galaxy sample. We analyzed the emission-line luminosity functions, reddening, and other gas diagnostics. The narrow-line regions…

Astrophysics of Galaxies · Physics 2017-09-13 Matthew A. Malkan , Lisbeth D. Jensen , David R. Rodriguez , Luigi Spinoglio , Brian Rush

We present a large sample which contains 45 Seyfert 1 galaxies (Sy1s), 46 hidden broad-line region (HBLR) Seyfert 2 galaxies (Sy2s), 57 non-HBLR Sy2s, and 22 starburst galaxies to distinguish their properties and to seek the possible…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Yu-Zhong Wu , Yong-Heng Zhao , Xian-Min Meng

An optical spectropolarimetric study has shown that the detectability of polarised broad H-alpha in Seyfert 2 galaxies is correlated to the IRAS f60/f25 flux ratio where only those Seyfert 2s with "warm" IRAS colours show polarised broad…

Astrophysics · Physics 2007-05-23 D. M. Alexander

We present observations in the 0.1-100 keV spectral band of 8 Seyfert 2 galaxies, obtained by means of BeppoSAX. These sources were selected according to their [OIII] optical emission line flux, to avoid biases against obscuration on the pc…

Astrophysics · Physics 2007-05-23 R. Maiolino , M. Salvati , L. Bassani , M. Dadina , R. Della Ceca , G. Matt , G. Risaliti , G. Zamorani

We present an analysis of six 12 um selected Seyfert 2 galaxies that have been reported to be unabsorbed in the X-ray. By comparing the luminosities of these galaxies in the mid-IR (12um), optical ([O III]) and hard X-ray (2-10 keV), we…

Astrophysics · Physics 2009-11-13 Murray Brightman , Kirpal Nandra

It is well known that the [O {\sc iii}]$\lambda$5007 emission line and hard X-ray(2-10keV) luminosities are good indicators of AGN activities and that the near and mid-infrared emission of AGN originates from re-radiation of dusty clouds…

Astrophysics · Physics 2009-11-11 ZhiXin Peng , Qiusheng Gu , Jorge Melnick , Yinghe Zhao

We present the BAT AGN Spectroscopic Survey (BASS) Near-infrared Data Release 2 (DR2), a study of 168 nearby ($\bar z$ = 0.04, $z$ < 0.6) active galactic nuclei (AGN) from the all-sky Swift Burst Array Telescope X-ray survey observed with…

We have carried out an analysis of the radio and optical properties of a statistical sample of 45 Seyfert galaxies from the Palomar spectroscopic survey of nearby galaxies. We find that the space density of bright galaxies (-22 mag <=…

Astrophysics · Physics 2009-11-06 James S. Ulvestad , Luis C. Ho

We analyze X-ray spectra and images of a sample of Seyfert 2 galaxies that unambiguously contain starbursts, based on their optical and UV characteristics. Although all sample members contain active galactic nuclei (AGNs), supermassive…

Astrophysics · Physics 2009-10-31 N. A. Levenson , K. A. Weaver , T. M. Heckman

We have made high-quality measurements of the polarization spectra of 13 FR II radio galaxies and taken polarization images for 11 of these with the Keck telescopes. Seven of the eight narrow-line radio galaxies (NLRG) are polarized, and…

Astrophysics · Physics 2009-10-31 M. H. Cohen , P. M. Ogle , H. D. Tran , R. W. Goodrich , J. S. Miller