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Related papers: Seyfert 2 Galaxies with Spectropolarimetric Observ…

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This paper presents a comprehensive study of the X-ray properties of low-ionization nuclear emission-line regions (LINERs) and low-luminosity Seyfert galaxies based on observations obtained with ASCA. We analyzed data of 53 observations of…

Astrophysics · Physics 2009-11-07 Yuichi Terashima , Naoko Iyomoto , Luis C. Ho , Andrew F. Ptak

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…

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

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…

Here we present the first results from the Siding Spring Southern Seyfert Spectroscopic Snapshot Survey (S7) which aims to investigate the physics of ~140 radio-detected southern active Galaxies with z<0.02 through Integral Field…

Broad-line radio galaxies (BLRGs) are active galactic nuclei that produce powerful, large-scale radio jets, but appear as Seyfert 1 galaxies in their optical spectra. In the X-ray band, BLRGs also appear like Seyfert galaxies, but with…

In the last decade of Active Galactic Nuclei (AGN) monitoring programs, the Mets\"ahovi Radio Observatory detected multiple times seven powerful flaring narrow-line Seyfert 1 (NLS1) galaxies at 37 GHz. Several hypotheses have been proposed,…

We present the results of hard-X-ray observations of four broad-line radio galaxies (BLRGs) with the Rossi X-Ray Timing Explorer (RXTE). The original motivation behind the observations was to search for systematic differences between the…

Astrophysics · Physics 2009-10-31 M. Eracleous , R. M. Sambruna , R. F. Mushotzky

This paper presents a quantification of the X-ray variability amplitude for 79 ASCA observations of 36 Seyfert 1 galaxies. We find that consideration of sources with the narrowest permitted lines in the optical band introduces scatter into…

Astrophysics · Physics 2009-10-31 T. J. Turner , I. M. George , K. Nandra , D. Turcan

Far-Infrared (FIR) photometry from the the Photodetector Array Camera and Spectrometer (PACS) on the Herschel Space Observatory is presented for 313 nearby, hard X-ray selected galaxies from the 58-month Swift Burst Alert Telescope (BAT)…

Astrophysics of Galaxies · Physics 2015-06-22 M. Meléndez , R. F. Mushotzky , T. T. Shimizu , A. J. Barger , L. L. Cowie

We compile a sample of 89 Seyfert galaxies with both [OIV] 25.89 um line luminosities observed by Spitzer IRS and X-ray spectra observed by XMM EPIC. Using [OIV] emission as proxy of AGN intrinsic luminosity, we find that although type 2…

High Energy Astrophysical Phenomena · Physics 2013-01-16 Teng Liu , Jun-Xian Wang

We present near-infrared K-band slit spectra of the nuclei of 25 Seyfert 2 galaxies in the CfA and 12 micron samples. The strength of the CO absorption features at 2.3-2.4 micron produced by stars is measured in terms of a spectroscopic CO…

Astrophysics · Physics 2009-11-10 Masatoshi Imanishi , Almudena Alonso-Herrero

We report on sensitive dual-frequency (1.7 and 5 GHz) European VLBI Network observations of the central region of nine Seyfert galaxies. These sources are among the faintest and least luminous members of a complete sample of nearby (d<22…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 P. Bontempi , M. Giroletti , F. Panessa , M. Orienti , A. Doi

In a previous paper (Veron et al. 1997) we presented medium resolution (3.4 A FWHM) spectroscopic observations of 15 "transition objects", selected for having an ambiguous location in the Veilleux & Osterbrock (1987) diagnostic diagrams,…

Astrophysics · Physics 2009-10-31 A. C. Goncalves , M. -P. Veron-Cetty , P. Veron

We report on a set of AGN that match the Seyfert 2 galaxy classification criteria, but display unusually wide "narrow" lines, with the 4959 {\AA} and 5007 {\AA} nebular lines overlapping with each other. This spectral line broadening is in…

Astrophysics of Galaxies · Physics 2014-12-16 Hartmut Winkler , Trevor Chauke

We investigate the ionization mechanisms for hidden broad-line region (HBLR) and non-HBLR Seyfert 2 galaxies by comparing some optical emission line ratios. We note that the [N II]6583/H_alpha ratio of the non-HBLR Seyfert 2 galaxies is…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Po-Chieh Yu , Chorng-Yuan Hwang

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…

We examine a representative sample of 35 Seyfert 2 nuclei. Previous work has shown that nearly 1/2 of these nuclei show the direct (but difficult-to-detect) spectroscopic signatures at optical-UV wavelengths of the hot massive stars that…

Obscured active galactic nuclei, which are classified optically as type 2 (narrow-line) Seyfert galaxies in the local universe, are by far the most promising candidates for the origin of the hard (2-10 keV) X-ray background radiation.…

Astrophysics · Physics 2009-11-07 E. C. Moran , A. V. Filippenko , R. Chornock

We present the results of an extensive literature search of multiwavelength data for a sample of 59 galaxies, consisting of 26 Starbursts, 15 Seyfert 2's, 5 LINER's, 6 normal spirals and 7 normal elliptical galaxies. The data include soft…

Astrophysics · Physics 2009-10-30 H. R. Schmitt , A. L. Kinney , D. Calzetti , T. Storchi-Bergmann

This is the third in a series of papers reporting on a large reverberation-mapping campaign aimed to study the properties of active galactic nuclei (AGNs) with high accretion rates. We present new results on the variability of the optical…

Astrophysics of Galaxies · Physics 2015-05-27 Chen Hu , Pu Du , Kai-Xing Lu , Yan-Rong Li , Fang Wang , Jie Qiu , Jin-Ming Bai , Shai Kaspi , Luis C. Ho , Hagai Netzer , Jian-Min Wang
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