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We present a detailed characterization of the X-ray spectral properties of 761 type 1 AGN, selected from a cross-correlation of the SDSS DR5 quasar catalogue and the incremental version of the second XMM-Newton serendipitous X-ray source…

High Energy Astrophysical Phenomena · Physics 2015-05-28 A. E. Scott , G. C. Stewart , S. Mateos , D. M. Alexander , S. Hutton , M. J. Ward

We undertake a spectral study of a sample of bright X-ray sources taken from six XMM-Newton fields at high galactic latitudes, where AGN are the most populous class. These six fields were chosen such that the observation had an exposure…

High Energy Astrophysical Phenomena · Physics 2015-05-30 M. A. Hassan , B. A. Korany , R. Misra , I. A. M. Issa , M. K. Ahmed , F. A. Abdel-Salam

We have observed with XMM-Newton four radiatively efficient active type 1 galaxies with black hole masses < 10^6 Msun, selected optically from the SDSS. We show here that their soft X-ray spectrum exhibits a soft excess with the same…

Astrophysics · Physics 2009-11-13 G. Miniutti , G. Ponti , J. E. Greene , L. C. Ho , A. C. Fabian , K. Iwasawa

(abridged) The soft excess seen in the X-ray spectra of many high mass accretion rate AGN can be well modelled by reflection from a partially ionised accretion disc. However, the derived parameters are often extreme, both in terms of the…

Astrophysics · Physics 2009-11-13 M. J. Middleton , C. Done , M. Gierlinski

The origin of the soft excess seen in many AGN below ~1 keV is still an unsolved problem. It is unlikely to represent a true continuum component as its characteristic 'temperature' shows a remarkable constancy over a wide range of AGN…

Astrophysics · Physics 2009-11-11 Marek Gierlinski , Chris Done

We discuss the broad band X-ray properties of one of the largest samples of X-ray selected type-1 AGN to date (487 objects in total), drawn from the XMM-Newton Wide Angle Survey. The objects cover 2-10 keV luminosities from ~10^{42}-10^{45}…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 S. Mateos , F. J. Carrera , M. J. Page , M. G. Watson , A. Corral , J. A. Tedds , J. Ebrero , M. Krumpe , A. Schwope , M. T. Ceballos

We investigate the nature of the soft excess below 1 keV observed in AGN. We use the XMM-Newton data of the low redshift, optically bright quasar, PG 1211+143, and we compare it with the Narrow Line Seyfert 1 galaxy, 1H 0707-495, which has…

Astrophysics · Physics 2008-11-26 Malgorzata A. Sobolewska , Chris Done

We investigate the nature of the soft excess below 1 keV observed in AGN. We use the XMM-Newton data of the low redshift, optically bright quasar, PG 1211+143, and we compare it with the Narrow Line Seyfert 1 galaxy, 1H 0707-495, which has…

Astrophysics · Physics 2016-08-30 Malgorzata Sobolewska , Chris Done

We study the X-ray properties of a sample of 14 optically-selected low-mass AGN whose masses lie within the range 1E5 -2E6 M(solar) with XMM-Newton. Only six of these low-mass AGN have previously been studied with sufficient quality X-ray…

High Energy Astrophysical Phenomena · Physics 2015-06-23 R. M. Ludlam , E. M. Cackett , K. Gultekin , A. C. Fabian , L. Gallo , G. Miniutti

We systematically analyse all publicly available XMM-Newton spectra of radio-quiet PG quasars. The soft X-ray excess in these objects is well modelled by an additional, cool, Compton scattering region. However, the remarkably constant…

Astrophysics · Physics 2009-11-10 Marek Gierlinski , Chris Done

An excess of X-ray emission below 1 keV, called soft excess, is detected in a large fraction of Seyfert 1-1.5s. The origin of this feature remains debated, as several models have been suggested to explain it, including warm Comptonization…

High Energy Astrophysical Phenomena · Physics 2016-03-23 Rozenn Boissay , Claudio Ricci , Stéphane Paltani

This paper presents the results of a detailed X-ray spectral analysis of a sample of 123 X-ray sources (46 being type-1 AGN and 28 type-2 AGN) detected with XMM-Newton in the Lockman Hole field. Using a single power law model our sources'…

We report on the spectral properties of a sample of 90 hard X-ray selected serendipitous sources detected in 12 XMM observations with 1<F(2-10)<80 10^(-14) erg/cm2/s. Approximately 40% of the sources are optically identified with 0.1<z<2…

Astrophysics · Physics 2009-11-10 E. Piconcelli , M. Cappi , L. Bassani , G. Di Cocco , M. Dadina

The nature and origin of the soft X-ray excess in radio quiet AGN is still an open issue. The interpretation in terms of thermal disc emission has been challanged by the discovery of the constancy of the effective temperature despite the…

Astrophysics · Physics 2009-11-13 F. D'Ammando , S. Bianchi , E. Jimenez-Bailon , G. Matt

We present here a detailed X-ray spectral analysis of the AGN belonging to the XMM-Newton bright survey (XBS) that comprises more than 300 AGN up to redshift ~ 2.4. We performed an X-ray analysis following two different approaches: by…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 A. Corral , R. Della Ceca , A. Caccianiga , P. Severgnini , H. Brunner , F. J. Carrera , M. J. Page , A. D. Schwope

We present optical and X-ray data for a sample of serendipitous XMM-Newton sources that are selected to have 0.5-2 keV vs 2-4.5 keV X-ray hardness ratios which are harder than the X-ray background. The sources have 2-4.5 keV X-ray flux >=…

The 2-10 keV continuum of AGN is generally well represented by a single power law. However, at smaller energies the continuum displays an excess with respect to the extrapolation of this power law, called the ''soft X-ray excess''. Until…

We report on the results of a detailed analysis of the X-ray spectral properties of a large sample of sources detected serendipitously with the XMM-Newton observatory in 25 selected fields. The survey covers a total solid angle of ~3.5 deg2…

We present the results of a uniform analysis of the soft X-ray spectra of fifteen type I AGN observed with the high resolution X-ray gratings on board \emph{Chandra}. We found that ten of the fifteen AGN exhibit signatures of an intrinsic…

Astrophysics · Physics 2019-08-19 Barry McKernan , Tahir Yaqoob , Chris Reynolds

We present a large sample of type 1 AGN spectra taken with XMM-Newton. We fit them with the relativistically blurred photoionized disc model of Ross & Fabian (2005). This model is based on an illuminated accretion disc of fluorescing and…

Astrophysics · Physics 2007-05-23 J Crummy , AC Fabian , L Gallo , RR Ross
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