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相关论文: Nuclear obscuration and scattering in Seyfert 2 ga…

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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…

天体物理学 · 物理学 2008-11-26 X. W. Shu , J. X. Wang , P. Jiang , L. L. Fan , T. G. Wang

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 use hard X-ray data for an "optimal" sample of Seyfert 2 galaxies to derive the distribution of the gaseous absorbing column densities among obscured active nuclei in the local Universe. Of all Seyfert 2 galaxies in the sample, 75% are…

天体物理学 · 物理学 2009-10-31 G. Risaliti , R. Maiolino , M. Salvati

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…

高能天体物理现象 · 物理学 2015-05-27 Yu-Zhong Wu , En-Peng Zhang , Yan-Chun Liang , Cheng-Min Zhang , Yong-Heng Zhao

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…

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 2009-10-31 D. M. Alexander

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 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

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

We have studied the correlation among X-ray absorption, optical reddening and nuclear dust morphology in Seyfert 2 galaxies. Two main conclusions emerge: a) the Balmer decrement and the amount of X-ray absorption are anticorrelated on a…

天体物理学 · 物理学 2009-11-06 M. Guainazzi , F. Fiore , G. Matt , G. C. Perola

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

We obtained 500-second F606W WFPC2 images of 256 of the nearest (z<0.035) Seyfert 1,Seyfert 2, and starburst galaxies. Less than 10% show tidal features or multiple nuclei. The incidence of inner starburst rings is about 10% in both classes…

天体物理学 · 物理学 2009-10-30 M. A. Malkan , V. Gorjian , R. Tam

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…

天体物理学 · 物理学 2009-10-31 A. Alonso-Herrero , A. C. Quillen , C. Simpson , A. Efstathiou , M. J. Ward

A sample of X-ray and optically selected narrow emission-line galaxies (769 sources) from the 3XMM catalogue cross-correlated with SDSS (DR9) catalogue has been studied. Narrow-emission line active galactic nuclei (AGN; type-2) have been…

高能天体物理现象 · 物理学 2016-10-19 Estelle Pons , Mike G. Watson

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 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

We present optical broad band B-I colour maps of a further sample of 10 Seyfert 2 galaxies. In these bands, the contribution from emission lines to the total flux is small, and hence the images predominantly trace the continuum…

天体物理学 · 物理学 2009-10-30 J. K. Kotilainen

This paper is the second in a series, studying the optical properties of a sample of mid-IR Warm Seyfert galaxies and a control sample of mid-IR Cold galaxies. The present paper is devoted to aperture photometry. We discuss nuclear (within…

天体物理学 · 物理学 2009-10-31 Eleni T. Chatzichristou

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

For the first time, the sulphur abundance relative to hydrogen (S/H) in the Narrow Line Regions of a sample of Seyfert 2 nuclei (Sy 2s) has been derived via direct estimation of the electron temperature. Narrow emission line intensities…

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