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Related papers: Seyfert 2 Galaxies with Spectropolarimetric Observ…

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We have studied the linear polarization of 86 active galactic nuclei (AGN) in the observed frequency range 80-267 GHz (3.7-1.1mm in wavelength), corresponding to rest-frame frequencies 82-738 GHz, with the IRAM Plateau de Bure…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 S. Trippe , R. Neri , M. Krips , A. Castro-Carrizo , M. Bremer , V. Pietu , A. L. Fontana

We present new spectropolarimetry of a sample of nearby Compton-thin Seyfert 2 galaxies (ie those with N_H<10^23 cm^-2). We show that the detection rate of scattered broad Halpha in this sample is considerably higher than in Seyfert 2…

Astrophysics · Physics 2007-05-23 S. L. Lumsden , D. M. Alexander , J. H. Hough

We present preliminary results of the spectral analysis of a large sample of Seyfert galaxies observed by BeppoSAX. The only selection criterium was a sufficiently large S/N ratio (>10) in the PDS band (12-200 keV) to allow good detection…

Astrophysics · Physics 2009-11-10 P. O. Petrucci , M. Dadina

In the past few years more and more pieces of evidence have been presented for a revision of the widely accepted Unified Model of Active Galactic Nuclei. A model based solely on orientation cannot explain all the observed phenomenology. In…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Andrea Marinucci , Stefano Bianchi , Fabrizio Nicastro , Giorgio Matt , Andy D. Goulding

The results of spectropolarimetry surveys of obscured AGNs are reviewed, paying special attention to their implications for the existence of two populations of type 2 Seyfert galaxies -- hidden Seyfert 1s and "true" Seyfert 2s. In this…

Astrophysics · Physics 2007-05-23 Edward C. Moran

The first short part of this review is a general, but very detailed, critique of the literature advocating a class of Seyfert galaxies intrinsically lacking broad emission lines. My conclusion is that there is little or no evidence for such…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-11 Robert Antonucci

To understand the origin of radio emission in radio-quiet AGN and differentiate between the contributions from star formation, AGN accretion, and jets, we have observed a nearby sample of Seyfert galaxies along with a comparison sample of…

Astrophysics of Galaxies · Physics 2020-10-14 Biny Sebastian , P. Kharb , C. P. O' Dea , J. F. Gallimore , S. A. Baum

We analyze the $2-10$~keV X-ray emission of complete samples of AGN and galaxies selected at 12$\mu$m and recently compiled by Rush, Malkan \& Spinoglio (1993). As a necessary complement we also study the IR emissivity of the largest sample…

Astrophysics · Physics 2016-08-30 X. Barcons , A. Franceschini , G. De Zotti , L. Danese , T. Miyaji

We derive a new relation between the metallicity of Seyfert 2 Active Galactic Nuclei (AGNs) and the intensity of the narrow emission-lines ratio $N2O2$=log([N II]$\lambda$6584/[O II]$\lambda$3727). The calibration of this relation was…

Astrophysics of Galaxies · Physics 2017-02-01 C. S. Castro , O. L. Dors , M. V. Cardaci , G. F. Hagele

We have compared the optical emission line ratios of type 2 quasars from Zakamska et al. with standard AGN photoionization model predictions, Seyfert 2s, HII galaxies, and narrow line FRII radio galaxies. Moderate to high ionization narrow…

We consider the sample of Tran (2001) to study the X-ray properties of Seyfert 2 galaxies with and without polarized broad lines.

Astrophysics · Physics 2007-05-23 Andrea Martocchia , Giorgio Matt

We have studied the relationship between the high- and low-ionization [O IV] lambda 25.89 micron, [Ne III] lambda 15.56 micron and [Ne II] lambda 12.81 micron emission lines with the aim of constraining the active galactic nuclei (AGN) and…

We report on a study of long-term flux variations in a sample of more than 1000 AGN observed with ROSAT and in the XMM-Newton slew survey. Over a period of 3-19 years, NLS1 galaxies as a class are found to be only slightly more variable…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-20 Richard Saxton , Andrew Read , Pilar Esquej , Giovanni Miniutti , Emilio Alvarez

We provide a comprehensive census of the near-Infrared (NIR, 0.8-2.4 $\mu$m) spectroscopic properties of 102 nearby (z < 0.075) active galactic nuclei (AGN), selected in the hard X-ray band (14-195 keV) from the Swift-Burst Alert Telescope…

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…

Astrophysics · Physics 2015-06-24 Laura E. Kay , Edward C. Moran

(Abbreviated) We assemble a sample composed of 243 nearby Seyfert galaxies with redshifts $z\le 0.05$ to test the unification scheme. The sample contains 94 BLS1s, 44 NLS1s, 36 X-ray absorbed HBLR S2s, 42 X-ray absorbed non-HBLR S2s and 27…

Astrophysics · Physics 2011-02-11 Jian-Min Wang , En-Peng Zhang

Results are presented of extended and refined optical identification of 181 radio/X-ray sources in the RASS-Green Bank (RGB) catalog which have been spectroscopically observed in the Sloan digital sky survey (SDSS) DR5. For 72 sources, the…

High Energy Astrophysical Phenomena · Physics 2009-09-24 Deliang Wang , Jianguo Wang , Xiaobo Dong

Using the 3XMM catalogue of serendipitous X-ray sources, and the SDSS-DR9 spectroscopic catalogue, we have obtained a new sample of X-ray selected narrow emission line galaxies. The standard optical diagnostic diagram and selection by hard…

High Energy Astrophysical Phenomena · Physics 2014-09-05 Estelle Pons , Mike G. Watson

We present 180 AGN candidates based on color selection from the IRAS slow-scan deep observations, with color criteria broadened from the initial Point-Source Catalog samples to include similar objects with redshifts up to z=1 and allowing…

The role of starburst winds versus active galactic nuclei (AGN) jets/winds in the formation of the kiloparsec scale radio emission seen in Seyferts is not yet well understood. In order to be able to disentangle the role of various…

Astrophysics of Galaxies · Physics 2019-12-23 Biny Sebastian , P. Kharb , C. P. O' Dea , J. F. Gallimore , S. A. Baum , E. J. M. Colbert
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