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Related papers: Unabsorbed Seyfert 2 galaxies

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The first X-ray observation of the Seyfert 2 galaxy NGC5252 is reported. ASCA collected $\sim 4000$ photons/detector enough to perform an accurate spectral analysis of this source. The luminosity of NGC5252 is L$_{\rm X}$(0.7-10 keV)…

Astrophysics · Physics 2009-10-28 M. cappi , T. Mihara , M. Matsuoka , W. Brinkmann , M. A. Prieto , G. G. C. Palumbo

We have launched a search for large-scale ($\gapprox$1 kpc) minor-axis outflows in edge-on Seyfert galaxies in order to assess their frequency of occurrence and study their properties. Here we present optical continuum and \han2 line images…

Deep X-ray surveys have resolved much of the X-ray background radiation below 2 keV into discrete sources, but the background above 8 keV remains largely unresolved. The obscured (type 2) Active Galactic Nuclei (AGNs) that are expected to…

Astrophysics · Physics 2008-11-26 K. C. Peterson , S. C. Gallagher , A. E. Hornschemeier , M. P. Muno , E. C. Bullard

We present a study of the stellar populations in the central ~ 200 pc of a large and homogeneous sample comprising 79 nearby galaxies, most of which are type 2 Seyferts. The star-formation history of these nuclei is reconstructed by means…

In the unification scheme of Seyfert galaxies, a dusty torus blocks the continuum source and broad line region in Seyfert 2 galaxies. However it is not clear whether or not and to what extent the torus affects the narrow line spectra. In…

Astrophysics · Physics 2010-11-09 Kai Zhang , Tinggui Wang , Xiaobo Dong , Honglin Lu

We present modeling to explore the conditions of the broad-line emitting gas in two extreme Narrow-line Seyfert 1 galaxies, using the observational results described in the first paper of this series. Photoionization modeling using Cloudy…

Astrophysics · Physics 2009-11-10 Karen M. Leighly

We present the AGN, star-forming, and morphological properties of a sample of 13 MIR-luminous (f(24) > 700uJy) IR-bright/optically-faint galaxies (IRBGs, f(24)/f(R) > 1000). While these z~2 sources were drawn from deep Chandra fields with…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 J. L. Donley , G. H. Rieke , D. M. Alexander , E. Egami , P. G. Perez-Gonzalez

Recently, Zakamska et al. (2003) selected 291 high-ionization narrow emission-line AGN in the redshift range 0.3-0.83 from the Sloan Digital Sky Survey spectroscopic data. The sample includes both Seyfert II galaxies and their higher…

Astrophysics · Physics 2009-11-10 C. Vignali , D. M. Alexander , A. Comastri

We present a detailed study of the X-ray and optical spectra of the luminous Seyfert galaxy Mrk 1393, which revealed variable partial obscuration of the active nucleus. The X-ray spectra obtained by XMM-Newton and Swift show moderate…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 T. G. Wang , H. Y. Zhou , D. Grupe , W. M. Yuan , X. B. Dong , H. L. Lu

We present evidence that the outflowing UV absorbers in Seyfert 1 galaxies arise primarily in their inner narrow (emission) line regions (NLRs), based on similarities in their locations, kinematics, and physical conditions. 1) Hubble Space…

Astrophysics · Physics 2009-11-10 D. M. Crenshaw , S. B. Kraemer

The properties of the absorption in type 2, narrow line AGNs are reviewed by focusing on the X-ray indicators. I discuss the properties of the cold absorbing medium (the putative torus) and of the reprocessed components, as well as their…

Astrophysics · Physics 2009-10-31 R. Maiolino

We have studied the average 3-200 keV spectra of Seyfert galaxies of type 1 and 2, using data obtained with BeppoSAX. The average Seyfert 1 spectrum is well-fitted by a power law continuum with photon spectral index Gamma~1.9, a Compton…

Astrophysics · Physics 2009-11-07 A. Malizia , L. Bassani , J. B. Stephen , G. Di Cocco , F. Fiore , A. J. Dean

We report the Rossi X-ray Timing Explorer observations of the heavily absorbed Seyfert 2 galaxy NGC 4945, which confirm the large column density of the absorber, corresponding to the optical depth to Thomson scattering of about 2.4. The…

Astrophysics · Physics 2009-10-31 G. M. Madejski , P. T. Zycki , C. Done , A. Valinia , P. Blanco , R. Rothschild , B. Turek

We have conducted an extensive X-ray spectral variability study of a sample of 20 Compton-thin type II galaxies using broad band spectra from XMM-Newton, Chandra, and Suzaku. The aim is to study the variability of the neutral intrinsic…

Astrophysics of Galaxies · Physics 2020-07-15 Sibasish Laha , Alex G. Markowitz , Mirko Krumpe , Robert Nikutta , Richard Rothschild , Tathagata Saha

We present a composite 1-10 keV Seyfert 2 X-ray spectrum, derived from ASCA observations of a distance-limited sample of nearby galaxies. All 29 observed objects were detected. Above ~3 keV, the composite spectrum is inverted, confirming…

Astrophysics · Physics 2009-11-06 Edward C. Moran , Laura E. Kay , Marc Davis , Alexei V. Filippenko , Aaron J. Barth

Type II quasars are the long-sought luminous analogs of type II (narrow emission line) Seyfert galaxies, suggested by unification models of active galactic nuclei (AGN) and postulated to account for an appreciable fraction of the cosmic…

X-ray variability is very common in active galactic nuclei (AGN), but these variations may not occur similarly in different families of AGN. We aim to disentangle the structure of low ionization nuclear emission line regions (LINERs)…

Astrophysics of Galaxies · Physics 2016-06-15 Lorena Hernandez-Garcia , Josefa Masegosa , Omaira Gonzalez-Martin , Isabel Marquez , Jaime Perea

We present near-to-mid-infrared spectral energy distributions (SEDs) for 21 Seyfert galaxies, using subarcsecond resolution imaging data. Our aim is to compare the properties Seyfert 1 (Sy1) and Seyfert 2 (Sy2) tori using clumpy torus…

We present multi-component photoionization models allowing for local density inhomogeneities in the NLR to interpret the emission line spectra of Seyfert 2 galaxies. This approach leads to a successful match of a large set of line…

Astrophysics · Physics 2016-08-30 Stefanie Komossa , Hartmut Schulz

The broad band 0.1-200 keV spectra of a sample of 5 Seyfert 2 galaxies (NGC 7172, Mkn 3, NGC 2110, NGC 4507 and NGC 7674) have been measured within the first year of the $BeppoSAX$ Core program. All sources have been detected up to \~ 100…