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We present a study of the hard X-ray spectrum (>15 keV) of different classes of Seyfert galaxies observed with BeppoSAX/PDS. Using hard X-ray data, we avoid absorption effects modifying the Seyfert emission and have direct access to the…

Astrophysics · Physics 2009-11-07 S. Deluit , T. Courvoisier

We present a compilation of radio, infrared, optical and hard X-ray (2-10kev) data for a sample of 90 Seyfert 2 galaxies(Sy2s) with spectropolarimetric observations (41 Sy2s with detection of polarized broad lines (PBL) and 49 without PBL).…

Astrophysics · Physics 2016-08-17 Qiusheng Gu Jiehao Huang

The new $XMM-Newton$ data of seven Seyfert 2 galaxies with optical spectropolarimetric observations are presented. The analysis of 0.5 -- 10 keV spectra shows that all four Seyfert 2 galaxies with polarized broad lines (PBLs) are absorbed…

Astrophysics · Physics 2009-11-13 X. W. Shu , J. X. Wang , P. Jiang

We compile a large sample of 120 Seyfert 2 galaxies (Sy2s) which contains 49 hidden broad-line region (HBLR) Sy2s and 71 non-HBLR Sy2s. From the difference in the power sources between two groups, we test if HBLR Sy2s are dominated by…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Yu-Zhong Wu , En-Peng Zhang , Yan-Chun Liang , Cheng-Min Zhang , Yong-Heng Zhao

We build a large sample of Seyfert 2 galaxies (Sy2s) with both optical spectropolarimetric and X-ray data available, in which 29 Sy2s with the detection of polarized broad emission line (PBL) and 25 without. We find that for luminous Sy2s…

Astrophysics · Physics 2008-11-26 X. W. Shu , J. X. Wang , P. Jiang , L. L. Fan , T. G. Wang

We extend the analysis presented in Tran (2001) of a spectropolarimetric survey of the CfA and 12micron samples of Seyfert 2 galaxies (S2s). We confirm that S2s with hidden broad line regions (HBLRs) tend to have hotter circumnuclear dust…

Astrophysics · Physics 2009-11-07 Hien D. Tran

We have studied the average 3-200 keV spectra of Seyfert galaxies of type 1 and 2, using data obtained with BeppoSAX. The average Seyfert 1 spectrum is well-fitted by a power law continuum with photon spectral index Gamma~1.9, a Compton…

Astrophysics · Physics 2009-11-07 A. Malizia , L. Bassani , J. B. Stephen , G. Di Cocco , F. Fiore , A. J. Dean

The unified model of Seyfert galaxies suggests that there are hidden broad-line regions (HBLRs) in Seyfert 2 galaxies (S2s). However, there is increasing evidence for the appearance of a subclass of S2s lacking of HBLR (non-HBLR S2s). An…

Astrophysics · Physics 2008-11-26 E. -P Zhang , J. -M. Wang

The hidden broad-line regions (BLRs) in Seyfert 2 galaxies, which display broad emission lines (BELs) in their polarized spectra, are a key piece of evidence in support of the unified model for active galactic nuclei (AGNs). However, the…

Astrophysics of Galaxies · Physics 2017-05-03 Pu Du , Jian-Min Wang , Zhi-Xiang Zhang

Narrow Line Seyfert 1 galaxies represent a distinct category in the larger family of Type 1 Active Galactic Nuclei. The occurrence of emission line profiles not broader than 2000 km/s, combined with luminosity estimates comparable to those…

High Energy Astrophysical Phenomena · Physics 2011-06-14 G. La Mura , S. Ciroi , V. Cracco , D. Ilić , L. Č. Popović , P. Rafanelli

The Spitzer high resolution spectra of 72 Seyfert galaxies from the 12$\mu$m Galaxy Sample are presented and discussed. The presence of starburst components in these galaxies can be quantified by powerful mid-IR diagnostics tools (i.e.…

Astrophysics · Physics 2008-07-31 S. Tommasin , L. Spinoglio , K. Hainline , M. A. Malkan , H. Smith

We present a deep study of the average hard X-ray spectra of Seyfert galaxies. We analyzed all public INTEGRAL IBIS/ISGRI data available on all the 165 Seyfert galaxies detected at z<0.2. Our final sample consists of 44 Seyfert 1's, 29…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Claudio Ricci , Roland Walter , Thierry J. -L. Courvoisier , Stephane Paltani

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

According to the unified model of active galactic nuclei, Seyfert 2 galaxies are physically the same as Seyfert 1 objects and they possess a broad-line region (BLR), but it is hidden from the observer due to their orientation. In the past…

Astrophysics of Galaxies · Physics 2016-11-17 Georgi P. Petrov

We present the results of X-ray imaging and spectroscopic analysis of a sample of Seyfert 2 galaxies that contain starbursts, based on their optical and UV characteristics. These composite galaxies exhibit extended, soft, thermal X-ray…

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

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 2009-10-31 D. M. Alexander

We analyze the 0.5-10 keV spectra of six Seyfert 2 galaxies observed with the X-ray satellite ASCA: Mrk 3, Mrk 348, Mrk 1210, Mrk 477, NGC 7212, and Was 49b. These galaxies were selected based on their possession of optical polarized broad…

Astrophysics · Physics 2016-08-30 Hisamitsu Awaki , Shiro Ueno , Yoshiaki Taniguchi , Kimberly A. Weaver

We present a study of the local environment (<200 kpc/h) of 31 Hidden Broad Line Region (HBLR) and 43 non-HBLR Seyfert 2 galaxies (Sy2) in the nearby universe (z<0.04). To compare our findings, we constructed two control samples that match…

Astrophysics of Galaxies · Physics 2014-11-11 E. Koulouridis

We present an X-ray spectral analysis of a sample of 8 bona-fide Seyfert 2 galaxies, selected on the basis of their high $[OIII]\lambda5007$ flux, from the Ho et al. (1997) spectroscopic sample of nearby galaxies. We find that, in general,…

Astrophysics · Physics 2008-11-26 A. Pappa , I. Georgantopoulos , G. C. Stewart , A. L. Zezas

The $BeppoSAX$ archive is currently the largest reservoir of high sensitivity simultaneous soft and hard-X ray data of Seyfert galaxies. From this database all the Seyfert galaxies (105 objects of which 43 are type I and 62 are type II)…

Astrophysics · Physics 2009-11-13 Mauro Dadina
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