中文
相关论文

相关论文: The Frequency of Polarized Broad Emission Lines in…

200 篇论文

In order to determine whether unified models of active galactic nuclei apply to low-luminosity objects, we have undertaken a spectropolarimetric survey of of LINERs and Seyfert nuclei at the Keck Observatory. The 14 objects observed have a…

天体物理学 · 物理学 2009-10-31 A. J. Barth , A. V. Filippenko , E. C. Moran

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

We have identified 12 Seyfert 1 galaxies that exhibit optical polarization spectra similar to those of Seyfert 2 galaxies in which polarized broad-lines are detected. We present new spectropolarimetric observations of 3 of them: Was 45, Mrk…

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

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

We present the detection of extremely broad, double-peaked, highly polarized Halpha emission lines in the nuclei of the well-known Seyfert 2 galaxies NGC 2110 and NGC 5252. These hidden broad Halpha emission lines, visible only in scattered…

宇宙学与河外天体物理 · 物理学 2010-02-23 Hien D. Tran

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 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

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

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

The nuclei of Seyfert 1 galaxies exhibit a range of optical polarization characteristics that can be understood in terms of two scattering regions producing orthogonal polarizations: an extended polar scattering region (PSR) and a compact…

宇宙学与河外天体物理 · 物理学 2015-05-27 D. Batcheldor , A. Robinson , D. J. Axon , S. Young , S. Quinn , J. E. Smith , J. Hough , D. M. Alexander

The detection of polarized continuum and line emission from the nucleus of NGC 4258 by Wilkes et al. (1995) provides an intriguing application of the unified model of Seyfert nuclei to a galaxy in which there is known to be an edge-on,…

The Unification Model for active galactic nuclei posits that Seyfert 2s are intrinsically like Seyfert 1s, but that their broad-line regions (BLRs) are hidden from our view. A Seyfert 2 nucleus that truly lacked a BLR, instead of simply…

天体物理学 · 物理学 2008-11-26 Himel Ghosh , Richard W. Pogge , Smita Mathur , Paul Martini , Joseph C. Shields

We present near-infrared 1.5 - 2.5 micron moderate resolution long-slit spectra of two Seyfert 1 galaxies (NGC 1097 and NGC 1566), three Seyfert 2s (NGC 1386, NGC 4945 and NGC 5128) and one Seyfert 1.5 (NGC 3227), both parallel to…

天体物理学 · 物理学 2009-11-07 J. Reunanen , J. K. Kotilainen , M. A. Prieto

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…

星系天体物理 · 物理学 2017-05-03 Pu Du , Jian-Min Wang , Zhi-Xiang Zhang

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…

星系天体物理 · 物理学 2016-11-17 Georgi P. Petrov

Unified models of Seyfert galaxies, based on viewing angles, successfully explain the observed differences between type 1 and 2 Seyferts. The existence of a range in accretion rates relative to the Eddington rate (from broad-line Seyfert 1s…

天体物理学 · 物理学 2009-11-11 G. C. Dewangan , R. E. Griffiths

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.…

天体物理学 · 物理学 2008-07-31 S. Tommasin , L. Spinoglio , K. Hainline , M. A. Malkan , H. Smith

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

NGC 3147, NGC 4698 and 1ES 1927+654 are active galaxies that are classified as Seyfert 2s, based on the line ratios of strong narrow emission lines in their optical spectra. However, they exhibit rapid X-ray spectral variability and/or…

宇宙学与河外天体物理 · 物理学 2010-12-21 Hien D. Tran , James E. Lyke , Jeff A. Mader

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
‹ 上一页 1 2 3 10 下一页 ›