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Related papers: An X-ray view of absorbed INTEGRAL AGN

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[Abridged]We report on the broadband X-ray properties of a complete sample of absorbed Seyfert galaxies hard X-ray selected with INTEGRAL. The sample is composed of 33 sources: 15 are newly discovered above 20 keV while 18 are already known…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 A. De Rosa , F. Panessa , L. Bassani , A. Bazzano , A. Bird , R. Landi , A. Malizia , M. Molina , P. Ubertini

In this paper we report on the broadband X-ray properties of a complete sample of 33 absorbed Seyfert galaxies hard X-ray selected with integral. The high quality broadband spectra obtained with both xmm, and integral-IBIS data are well…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-21 A. De Rosa , F. Panessa , L. Bassani , A. Bazzano , A. J. Bird , R. Landi , A. Malizia , M. Molina , P. Ubertini

The 0.5-150 keV broad-band spectra of a sample of nine bright type 1 Seyfert galaxies are analyzed here. These sources have been discovered/detected by INTEGRAL and subsequently observed with XMM--Newton for the first time with high…

We study the NH distribution in a complete sample of 88 AGN selected in the 20-40 keV band from INTEGRAL/IBIS observations. We find that the fraction of absorbed (NH > 10^{22} cm^2) sources is 43% while the Compton thick AGN comprise 7% of…

High Energy Astrophysical Phenomena · Physics 2015-05-13 A. Malizia , J. B. Stephen , L. Bassani , A. J. Bird , F. Panessa , P. Ubertini

The determination of the broad (0.1-100 keV) spectra of active galaxies is crucial for understanding and discriminating among emission models, for estimating the properties of the Comptonising/reflecting region around the central black hole…

High Energy Astrophysical Phenomena · Physics 2013-02-12 Manuela Molina , L. Bassani , A. Malizia , A. Bazzano , P. Ubertini , A. J. Bird

AGN exhibit complex hard X-ray spectra. Our current understanding is that the emission is dominated by inverse Compton processes which take place in the corona above the accretion disk, and that absorption and reflection in a distant…

High Energy Astrophysical Phenomena · Physics 2009-06-25 V. Beckmann , T. J. -L. Courvoisier , N. Gehrels , P. Lubinski , J. Malzac , P. O. Petrucci , C. R. Shrader , S. Soldi

We present X-ray spectral analyses for three Seyfert 2 active galactic nuclei, NGC 424, NGC 1320, and IC 2560, observed by NuSTAR in the 3-79 keV band. The high quality hard X-ray spectra allow detailed modeling of the Compton reflection…

In this work we present the most comprehensive INTEGRAL AGN sample which lists 272 objects. Here we mainly use this sample to study the absorption properties of active galaxies, to probe new AGN classes and to test the AGN unification…

High Energy Astrophysical Phenomena · Physics 2015-06-05 A. Malizia , L. Bassani , A. Bazzano , A. J. Bird , N. Masetti , F. Panessa , J. B. Stephen , P. Ubertini

In this paper we discuss the broad-band X-ray characteristics of a complete sample of 36 type 1 AGN, detected by INTEGRAL in the 20-40 keV band above the 5.5sigma level. We present, for all the objects in the sample, the broad-band (1-110…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 M. Molina , L. Bassani , A. Malizia , J. B. Stephen , A. J. Bird , A. J. Dean , F. Panessa , A. De Rosa , R. Landi

Above $\sim$3 keV, the X-ray spectrum of the active galactic nuclei (AGN) is characterized by the intrinsic continuum and compton reflection features. For type-1 AGN, several regions could contribute to the reflection. In order to…

We study the NH distribution in a complete sample of 88 AGN selected in the 20-40 keV band from INTEGRAL/IBIS observations. We find that the fraction of absorbed (NH > 10^22 cm^-2) sources is 43% while Compton thick AGN comprise 7% of the…

High Energy Astrophysical Phenomena · Physics 2010-02-26 A. Malizia , J. B. Stephen , L. Bassani , A. J. Bird , F. Panessa , P. Ubertini

We report on the identification of the X/soft gamma-ray source AX J183039-1002 detected with ASCA and INTEGRAL/IBIS. The source, which has an observed 20-100 keV flux of about 8.6 x 10^-11 erg/cm^2/s, is inside a diffuse radio supernova…

Astrophysics of Galaxies · Physics 2009-11-13 L. Bassani , R. Landi , R. Campana , V. A. McBride , A. J. Dean , A. J. Bird , D. A. Green , P. Ubertini , A. De Rosa

The hard X-ray emission of active galactic nuclei (AGN), and in particular, the reflection component, is shaped by the innermost and outer regions of the galactic nucleus. Our main goal is to investigate the variation of the Compton hump…

Astrophysics of Galaxies · Physics 2019-07-05 Christos Panagiotou , Roland Walter

For a significant number of the sources detected at high energies (>10 keV) by the INTEGRAL/IBIS and Swift/BAT instruments there is either a lack information about them in the 2-10 keV range or they are totally unidentified. Herein, we…

Astrophysics · Physics 2009-11-13 A. Malizia , R. Landi , L. Bassani , A. J. Bird , M. Molina , A. De Rosa , M. Fiocchi , N. Gehrels , J. Kennea , M. Perri

We observed 7 INTEGRAL sources with the Chandra X-ray Observatory to refine their localization to ~2 arcsec and to study their X-ray spectra. Two sources are inferred to have a Galactic origin: IGR J08390-4833 is most likely a magnetic…

Astrophysics · Physics 2015-05-13 S. Sazonov , M. Revnivtsev , R. Burenin , E. Churazov , R. Sunyaev , W. R. Forman , S. S. Murray

We present the first results of the spectroscopy of distant, obscured AGN as obtained with the ultra-deep (~3.3 Ms) XMM-Newton survey in the Chandra Deep Field South (CDFS). One of the primary goals of the project is to characterize the…

We present X-ray spectral analysis of the brightest sources (f_{2-10 keV}>10^{-15}$ cgs) in the Chandra Deep Field North. Our sample consists of 222 sources; for the vast majority (171) either a spectroscopic or a photometric redshift is…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-02 I. Georgantopoulos , A. Akylas , A. Georgakakis , M. Rowan-Robinson

I present a review of X-ray and mid-IR surveys for Compton-thick Active Galactic Nuclei (AGN). These are the most highly obscured sources having hydrogen column densities >1.5x10^24 cm-2. Key surveys in the local Universe are presented…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 I. Georgantopoulos

Hard X-ray surveys are an important tool for the study of active galactic nuclei (AGN): they provide almost an unbiased view of absorption in the extragalactic population, allow the study of spectral features such as reflection and high…

High Energy Astrophysical Phenomena · Physics 2013-02-12 Loredana Bassani , M. Molina , A. Malizia , F. Panessa , R. Landi , A. Bazzano , P. Ubertini , A. J. Bird , J. B. Stephen

The fraction of AGN with photoelectric absorption in the X-rays ranging from NH of 10^{22} up to about 10^{24} cm^{-2} (Compton-thin) appears observationally to be anticorrelated to their luminosity Lx. This recently found evidence is used…

Astrophysics · Physics 2009-11-11 Alessandra Lamastra , G. Cesare Perola , Giorgio Matt
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