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Related papers: Heavy obscuration in X-ray weak AGNs

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We present Suzaku observations of five hard X-ray selected nearby Seyfert 2 galaxies. All the sources were clearly detected with the pin Hard X-ray Detector up to several tens of keV, allowing for a fairly good characterization of the…

High Energy Astrophysical Phenomena · Physics 2015-05-19 A. Comastri , K. Iwasawa , R. Gilli , C. Vignali , P. Ranalli , G. Matt , F. Fiore

We present the combined Chandra and Swift-BAT spectral analysis of seven Seyfert 2 galaxies selected from the Swift-BAT 100-month catalog. We selected nearby (z<=0.03) sources lacking of a ROSAT counterpart and never previously observed…

High Energy Astrophysical Phenomena · Physics 2017-02-22 Stefano Marchesi , Marco Ajello , Andrea Comastri , Giancarlo Cusumano , Valentina La Parola , Alberto Segreto

Hard X-ray selection is the most efficient way to discriminate between accretion-powered sources, such as AGN, from sources dominated by starlight. Hard X-rays are also less affected than other bands by obscuration. We have then carried out…

Astrophysics · Physics 2009-10-31 F. Fiore , F. La Franca , P. Giommi , M. Elvis , G. Matt , A. Comastri , S. Molendi , I. Gioia

(abridged)The majority of Active Galactic Nuclei (AGN) suffer from significant obscuration by surrounding dust and gas. X-ray surveys in the 2-10 keV band will miss the most heavily-obscured AGN in which the absorbing column density exceeds…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Stephanie M. LaMassa , Timothy M. Heckman , Andrew A. Ptak , Ann Hornschemeier , Lucimara Martins , Paule Sonnentrucker , Christy Tremonti

In this paper we discuss the X-ray properties of 49 local (z<0.035) Seyfert 2 galaxies with HST/WFC2 high-resolution optical coverage. It includes the results of 26 still unpublished Chandra and XMM-Newton observations, which yield 25 (22)…

Astrophysics · Physics 2009-11-11 M. Guainazzi , G. Matt , G. C. Perola

A sample of X-ray and optically selected narrow emission-line galaxies (769 sources) from the 3XMM catalogue cross-correlated with SDSS (DR9) catalogue has been studied. Narrow-emission line active galactic nuclei (AGN; type-2) have been…

High Energy Astrophysical Phenomena · Physics 2016-10-19 Estelle Pons , Mike G. Watson

Using self-consistent, physically motivated models, we investigate the X-ray obscuration in 19 Type 2 [OIII] 5007 \AA\ selected AGN, 9 of which are local Seyfert 2 galaxies and 10 of which are Type 2 quasar candidates. We derive reliable…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Stephanie M. LaMassa , Tahir Yaqoob , Andrew F. Ptak , Jianjun Jia , Timothy M. Heckman , Poshak Gandhi , C. Meg Urry

We present an analysis of six 12 um selected Seyfert 2 galaxies that have been reported to be unabsorbed in the X-ray. By comparing the luminosities of these galaxies in the mid-IR (12um), optical ([O III]) and hard X-ray (2-10 keV), we…

Astrophysics · Physics 2009-11-13 Murray Brightman , Kirpal Nandra

We report X-ray fluxes in the 2--10 keV band from LINERs (low-ionization nuclear emission-line regions) and low-luminosity Seyfert galaxies obtained with the ASCA satellite. Observed X-ray luminosities are in the range between 4e39 and 5e41…

Astrophysics · Physics 2009-10-31 Yuichi Terashima , Luis C. Ho , Andrew F. Ptak

We report on BeppoSAX broad band (0.1-100 keV) observations of bright Seyfert 2 galaxies and discuss the results in the framework of the unified theory of AGNs. The data are used to probe Nh distribution in type 2 objects and to identify…

Astrophysics · Physics 2007-05-23 L. Bassani , M. Cappi , G. Malaguti

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 report on an optical (SDSS) and X-ray (XMM) study of an optically selected sample of four dual AGN systems at projected separations of 30--60~kpc. All sources are detected in the X-ray band (0.3-10 keV); seven objects are optically…

Aims: The unification scheme of Seyfert galaxies predicts that the observed differences between type 1 and type 2 Seyfert galaxies are solely due to the differing orientations of the toroidal-shaped obscuring material around AGN. The…

High Energy Astrophysical Phenomena · Physics 2015-03-17 Veeresh Singh , Prajval Shastri , Guido Risaliti

Type 2 active galactic nuclei (AGN) show signatures of accretion onto a supermassive black hole through strong, high-ionization, narrow emission lines extended on scales of 100s to 1000s of parsecs, but they lack the broad emission lines…

High Energy Astrophysical Phenomena · Physics 2022-09-21 M. Lynne Saade , Murray Brightman , Daniel Stern , Matthew A. Malkan , Javier A. Garcia

We analyze the 0.5-10 keV spectra of six Seyfert 2 galaxies observed with the X-ray satellite ASCA: Mrk 3, Mrk 348, Mrk 1210, Mrk 477, NGC 7212, and Was 49b. These galaxies were selected based on their possession of optical polarized broad…

Astrophysics · Physics 2016-08-30 Hisamitsu Awaki , Shiro Ueno , Yoshiaki Taniguchi , Kimberly A. Weaver

We report the BeppoSAX detection of a hard X-ray excess in the X-ray spectrum of the classical high-ionization Seyfert 2 galaxy Tol0109-383. The X-ray emission of this source observed below 7 keV is dominated by reflection from both cold…

Astrophysics · Physics 2009-09-17 K. Iwasawa , G. Matt , A. C. Fabian , S. Bianchi , W. N. Brandt , M. Guainazzi , T. Murayama , Y. Taniguchi

This paper presents the analysis of a statistically complete sample of 28 serendipitous X-ray sources selected in 82 pointed XMM-Newton fields down to a count-rate of 0.002 counts s^-1(4.5-7.5 keV energy band). This is the first sample…

The integrated emission of highly obscured AGN is expected to provide a major contribution to the X-ray energy density in the Universe: the X-ray background (XRB). The study of these objects is possible only at energies where the effects of…

Astrophysics · Physics 2007-05-23 A. Comastri , F. Fiore , C. Vignali , F. La Franca , G. Matt

We present results of optical identification of the ASCA Large Sky Survey. X-ray sources which have hard X-ray spectra were identified with type-2 AGN at redshifts smaller than 0.5. It is supported that the absorbed X-ray spectrum of type-2…

Astrophysics · Physics 2021-07-14 M. Akiyama , K. Ohta , T. Yamada , Y. Ueda , T. Takahashi , M. Sakano , T. Tsuru , I. Lehmann , G. Hasinger

Results from BeppoSAX observations of Compton--thick Seyfert 2 galaxies are summarized and reviewed, and their general properties derived and discussed. In five out of the seven observed sources, the nucleus is directly visible at high…

Astrophysics · Physics 2016-08-30 G. Matt , A. C. Fabian , M. Guainazzi , K. Iwasawa , L. Bassani , G. Malaguti
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