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Related papers: On the Seyfert 2 warm and cool infrared dichotomy

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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…

Astrophysics · Physics 2009-10-31 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…

Astrophysics · Physics 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…

Astrophysics · Physics 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…

Astrophysics · Physics 2009-10-31 Qiusheng Gu , Roberto Maiolino , Deborah Dultzin-Hacyan

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).…

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

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 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,…

Astrophysics · Physics 2009-10-30 Karen M. Leighly , Laura E. Kay , Beverley J. Wills , D. Wills , Dirk Grupe

We report our analysis of X-ray spectra of the Seyfert galaxy IRAS 18325-5926 (=Fairall 49) obtained from various X-ray observatories prior to XMM-Newton, including new results from two RXTE and one BeppoSAX observations. A relatively steep…

Astrophysics · Physics 2009-09-17 K. Iwasawa , J. C. Lee , A. J. Young , C. S. Reynolds , A. C. Fabian

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

We report long, pointed ROSAT HRI observations of the hyperluminous galaxies IRAS F00235+1024, F12514+1027, F14481+4454 and F14537+1950. Two of them are optically classified as Seyfert-like. No X-ray sources are detected at the positions of…

Astrophysics · Physics 2009-10-30 R. J. Wilman , A. C. Fabian , R. M. Cutri , C. S. Crawford , W. N. Brandt

IRAS 18325-5926 is an X-ray bright, Compton-thin, type-2 Seyfert galaxy and it was the first Seyfert 2 in which the presence of a broad Fe K-alpha emission line was claimed. However, although the structure of the Fe line appears broad,…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Andrew Lobban , Simon Vaughan

The relation between the X-ray, the coronal line and the infrared (IR) emissions in a sample of the brightest known Seyfert galaxies is analysed. A close relationship between the absorption-corrected soft X-ray emission and both the mid-IR…

Astrophysics · Physics 2009-11-07 M. A. Prieto , A. M. Perez Garcia , J. M. Rodriguez Espinosa

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…

Astrophysics · Physics 2009-10-31 Eleni T. Chatzichristou

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…

Astrophysics · Physics 2009-11-06 Hien D. Tran

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Hong-bing Cai , Xin-Wen Shu , Zhen-Ya Zheng , Jun-xian Wang

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…

Astrophysics · Physics 2008-11-26 J. E. Smith , S. Young , A. Robinson , E. A. Corbett , M. E. Giannuzzo , D. J. Axon , J. H. Hough

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…

Astrophysics · Physics 2009-11-07 Luigi Spinoglio , Paola Andreani , Matthew A. Malkan

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…

Astrophysics · Physics 2016-08-30 S. J. Deluit

This paper is the fourth in a series, studying the optical properties of a sample of mid-IR Warm Seyfert galaxies and of a control sample of mid-IR cold galaxies. The present paper is devoted to the analysis of the colour distributions…

Astrophysics · Physics 2007-05-23 Eleni T. Chatzichristou
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