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相关论文: The Unified model and the Seyfert 2 infrared dicho…

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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…

天体物理学 · 物理学 2007-05-23 D. M. Alexander

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…

天体物理学 · 物理学 2009-11-07 S. L. Lumsden , D. M. Alexander

We report the results of a spectropolarimetric survey of a complete far infrared selected sample of Seyfert 2 galaxies. We have found polarized broad Halpha emission in one new source, NGC5995. In the sample as a whole, there is a clear…

天体物理学 · 物理学 2009-11-06 S. L. Lumsden , C. A. Heisler , J. A. Bailey , J. H. Hough , S. Young

We study the relation between gaseous absorbing column density (N$_{\rm H}$), infrared colors and detectability of the broad lines in a large sample of Seyfert 2 galaxies(Sy2s). We confirm that Sy2s without polarized broad lines tend to…

天体物理学 · 物理学 2009-10-31 Qiusheng Gu , Roberto Maiolino , Deborah Dultzin-Hacyan

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…

天体物理学 · 物理学 2009-11-07 Hien D. Tran

Half of the Seyfert-2 galaxies escaped detection of broad lines in their polarised spectra observed so far. Some authors have suspected that these non-HBLRs contain real Sy2 nuclei without intrinsic broad line region hidden behind a dust…

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).…

天体物理学 · 物理学 2016-08-17 Qiusheng Gu Jiehao Huang

We present a series of statistical tests using homogeneous data and measurements for a sample of Seyfert galaxies. These galaxies were selected from mostly isotropic properties, their far infrared fluxes and warm infrared colors, which…

天体物理学 · 物理学 2007-05-23 H. R. Schmitt , J. S. Ulvestad , R. R. J. Antonucci , C. J. Clarke , J. E. Pringle , A. L. Kinney

We present a series of statistical tests done to a sample of 29 Seyfert 1 and 59 Seyfert 2 galaxies selected from mostly isotropic properties, their far infrared fluxes and warm infrared colors. Such selection criteria provide a profound…

天体物理学 · 物理学 2009-11-06 H. R. Schmitt , R. R. J. Antonucci , J. S. Ulvestad , A. L. Kinney , C. J. Clarke , J. E. Pringle

We present optical spectropolarimetry of the nuclei of 36 Seyfert 1 galaxies, obtained with the William Herschel and the Anglo-Australian Telescopes from 1996 to 1999. In 20 of these, the optical emission from the active nucleus is…

天体物理学 · 物理学 2008-11-26 J. E. Smith , S. Young , A. Robinson , E. A. Corbett , M. E. Giannuzzo , D. J. Axon , J. H. Hough

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…

天体物理学 · 物理学 2009-11-13 X. W. Shu , J. X. Wang , P. Jiang

We report the results of a spectropolarimetric survey of the CfA and 12micron samples of Seyfert 2 galaxies (S2s). Polarized (hidden) broad line regions (HBLRs) are confirmed in a number of galaxies, and several new cases (F02581-1136, MCG…

天体物理学 · 物理学 2009-11-06 Hien D. Tran

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…

天体物理学 · 物理学 2008-11-26 E. -P Zhang , J. -M. Wang

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…

宇宙学与河外天体物理 · 物理学 2013-09-27 Tobias Beuchert , Jörn Wilms , Matthias Kadler , Anna Lia Longinotti , Matteo Guainazzi , Giovanni Miniutti , Ignacio de la Calle

We study the hard X-ray emission of two samples of Seyfert 2 galaxies with and without Polarized Broad Lines (PBL). In the hard X-ray domain, absorption effects do not significantly modify the intrinsic emission allowing us a direct access…

天体物理学 · 物理学 2016-08-30 S. J. Deluit

We report the detection of ionized absorption in the ASCA spectrum of the narrow-line Seyfert 1 galaxy IRAS 17020+4544. Subsequent optical spectropolarimetry revealed high polarization increasing from 3% in the red to 5% in the blue,…

天体物理学 · 物理学 2009-10-30 Karen M. Leighly , Laura E. Kay , Beverley J. Wills , D. Wills , Dirk Grupe

From the literature, we construct from literature a sample of 25 Seyfert 2 galaxies (S2s) with a broad line region detected in near infrared spectroscopy and 29 with NIR BLR which was detected. We find no significant difference between the…

宇宙学与河外天体物理 · 物理学 2015-05-19 Hong-bing Cai , Xin-Wen Shu , Zhen-Ya Zheng , Jun-xian Wang

We have detected a broad H alpha emission line in the polarized flux spectrum of the Seyfert 2 galaxy NGC 788, indicating that it contains an obscured Seyfert 1 nucleus. While such features have been observed in ~15 other Seyfert 2s, this…

天体物理学 · 物理学 2015-06-24 Laura E. Kay , Edward C. Moran

X-ray unabsorbed Seyfert 2 galaxies appear to have X-ray absorption column densities that are too low (NH < 10^22 cm-2) to explain the absence of broad emission lines in their optical spectra, challenging the standard AGN unification model.…

高能天体物理现象 · 物理学 2011-05-25 Xing-Xing Huang , Jun-Xian Wang , Ying Tan , Huan Yang , Ya-Fang Huang

New far-infrared photometry with ISOPHOT, onboard the Infrared Space Observatory, is presented for 58 galaxies with homogeneous published data for another 32 galaxies all belonging to the 12 micron galaxy sample. In total 29 Seyfert 1's, 35…

天体物理学 · 物理学 2009-11-07 Luigi Spinoglio , Paola Andreani , Matthew A. Malkan
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