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Related papers: Tackling the soft X-ray excess in AGN with variabi…

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Mkn 841 has been observed during 3 different periods (January 2001, January 2005 and July 2005) by XMM-Newton for a total cumulated exposure time of ~108 ks. We present in this paper a broad band spectral analysis of the complete EPIC-pn…

We study the origin of the soft X-ray excess seen in the 'simple' Narrow Line Seyfert 1 galaxy PG1244+026 using all available spectral-timing information. This object shows the standard switch between soft leading the hard band on long…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Emma Gardner , Chris Done

The origin of short timescale (weeks/months) variability of AGN, whether due to intrinsic disc variations or reprocessing of X-ray emission by a surrounding accretion disc, has been a puzzle for many years. However recently a number of…

The X-ray quasi-periodic oscillation (QPO) seen in RE J1034+396 is so far unique amongst AGN. Here we look at the another unique feature of RE J1034+396, namely its huge soft X-ray excess, to see if this is related in any way to the…

Astrophysics · Physics 2015-05-13 Matthew Middleton , Chris Done , Martin Ward , Marek Gierlinski , Nick Schurch

In this review I briefly describe the latest advances in studies of aperiodic variability of accreting X-ray binaries and outline the model which currently describe the majority of observational appearances of variability of accreting…

Astrophysics · Physics 2014-11-18 M. Revnivtsev

One of the most important features in active galactic nuclei (AGN) is the variability of their emission. Variability has been discovered at X-ray, UV, and radio frequencies on time scales from hours to years. Among the AGN family and…

High Energy Astrophysical Phenomena · Physics 2015-06-15 L. Hernández-García , O. González-Martín , I. Márquez , J. Masegosa

Most investigations of the X-ray variability of active galactic nuclei (AGN) have been concentrated on the detailed analyses of individual, nearby sources. A relatively small number of studies have treated the ensemble behaviour of the more…

Astrophysics of Galaxies · Physics 2016-09-21 F. Vagnetti , R. Middei , M. Antonucci , M. Paolillo , R. Serafinelli

We present an overview on how variability can be used to constrain the location of the ionized outflow in nearby Active Galactic Nuclei using high-resolution X-ray spectroscopy. Without these constraints on the location of the outflow, the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 R. G. Detmers , J. S. Kaastra

We carried out a systematic analysis of time lags between X-ray energy bands in a large sample (32 sources) of unabsorbed, radio quiet active galactic nuclei (AGN), observed by XMM-Newton. The analysis of X-ray lags (up to the…

High Energy Astrophysical Phenomena · Physics 2015-06-03 B. De Marco , G. Ponti , M. Cappi , M. Dadina , P. Uttley , E. M. Cackett , A. C. Fabian , G. Miniutti

The bright, soft X-ray spectrum Seyfert 1 galaxies Ark 564 and Ton S180 were monitored for 35 days and 12 days with ASCA and RXTE (and EUVE for Ton S180). The short time scale (hours-days) variability patterns were very similar across…

We present the analysis of the X-ray variability and spectral timing properties of the ultraluminous X-ray source (ULX) NGC 5408 X-1, one of the most variable ULXs known so far. The variability properties are used as a diagnostic of the…

High Energy Astrophysical Phenomena · Physics 2015-06-17 B. De Marco , G. Ponti , G. Miniutti , T. Belloni , M. Cappi , M. Dadina , T. Muñoz-Darias

We present an XMM-Newton observation of the bright, narrow-line, ultrasoft Seyfert 1 galaxy Ton S180. The 0.3-10 keV X-ray spectrum is steep and curved, showing a steep slope above 2.5 keV (Gamma ~ 2.3) and a smooth, featureless excess of…

Astrophysics · Physics 2008-11-26 S. Vaughan , Th. Boller , A. C. Fabian , D. R. Ballantyne , W. N. Brandt , J. Trumper

The soft excess in active galactic nuclei (AGNs) may arise through a combination of relativistic reflection and the effects of a warm corona at the surface of the accretion disc. Detailed examination of the soft excess can therefore…

High Energy Astrophysical Phenomena · Physics 2024-04-05 D. R. Ballantyne , V. Sudhakar , D. Fairfax , S. Bianchi , B. Czerny , A. De Rosa , B. De Marco , R. Middei , B. Palit , P. -O. Petrucci , A. Rozanska , F. Ursini

XMM-Newton and NuSTAR multiple exposures allow us to disentangle the different emission components of active galactic nuclei (AGNs) and to study the evolution of their different spectral features. In this work, we present the timing and…

High Energy Astrophysical Phenomena · Physics 2020-10-07 R. Middei , P. -O. Petrucci , S. Bianchi , F. Ursini , M. Cappi , M. Clavel , A. De Rosa , A. Marinucci , G. Matt , A. Tortosa

Context. AGNs are strong X-ray emitters shaped by disk-corona interactions. The soft excess (0.5-2.0 keV) reveals key information about the "warm corona" bridging the disk and hot corona. Yet, how this feature evolves with accretion…

We have carried out a systematic analysis of the nearby (z=0.0279) active galaxy Zw 229.015 using multi-epoch, multi-instrument and deep pointed observations with XMM-Newton, Suzaku, Swift and NuSTAR. Spectral and temporal variability are…

High Energy Astrophysical Phenomena · Physics 2019-07-31 S. Tripathi , S. G. H. Waddell , L. C. Gallo , W. F. Welsh , C-Y. Chiang

Models of X-ray reverberation from extended coronae are developed from general relativistic ray tracing simulations. Reverberation lags between correlated variability in the directly observed continuum emission and that reflected from the…

High Energy Astrophysical Phenomena · Physics 2016-02-19 D. R. Wilkins , E. M. Cackett , A. C. Fabian , C. S. Reynolds

We present preliminary results on the variability properties of AGN above 20 keV in order to show the potential of the INTEGRAL IBIS/ISGRI and Swift/BAT instruments for hard X-ray timing analysis of AGN. The 15-50 keV light curves of 36 AGN…

High Energy Astrophysical Phenomena · Physics 2010-01-26 S. Soldi , G. Ponti , V. Beckmann , P. Lubinski

We present a large sample of type 1 active galactic nuclei (AGN) spectra taken with XMM-Newton, and fit them with both the conventional model (a power law and black body) and the relativistically-blurred photoionized disc reflection model…

Astrophysics · Physics 2009-09-17 J Crummy , AC Fabian , L Gallo , RR Ross

The 2-10 keV continuum of AGN is well represented by a single power law, generally attributed to a hot comptonizing medium, such as a corona above the accretion disk. At smaller energies the continuum displays an excess with respect to the…

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