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Related papers: A rapidly variable narrow X-ray iron line in Mkn 8…

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We present results of new ASCA observations of the low-luminosity AGN (LLAGN) NGC 4579 obtained on 1998 December 18 and 28, and we report on detection of variability of an iron K emission line. The X-ray luminosities in the 2--10 keV band…

Astrophysics · Physics 2009-10-31 Y. Terashima , L. C. Ho , A. F. Ptak , T. Yaqoob , H. Kunieda , K. Misaki , P. J. Serlemitsos

We present evidence from Beppo-SAX and XMM-Newton of extreme X-ray variability in the high luminosity radio-quiet quasar PDS 456, the most luminous known AGN at z<0.3. Repeated X-ray flaring is found in PDS 456, over the duration of the 340…

Astrophysics · Physics 2009-11-07 J. Reeves , G. Wynn , P. O'Brien , K. Pounds

We report the results of an XMM-Newton observation of the Narrow-Line Seyfert 1 galaxy Mkn 1239. This optically highly polarized AGN has one of the steepest X-ray spectra found in AGN with alpha-X = +3.0 based on ROSAT PSPC data. The…

Astrophysics · Physics 2009-11-10 D. Grupe , S. Mathur , S. Komossa

The unprecedented sensitivity of current X-ray telescopes allows for the first time to address the issue of the Fe K line complex variability patterns in bright, nearby AGNs. We examine XMM-Newton observations of the brightest sources of…

High Energy Astrophysical Phenomena · Physics 2015-05-13 B. De Marco , K. Iwasawa , M. Cappi , M. Dadina , F. Tombesi , G. Ponti , A. Celotti , G. Miniutti

We selected a sample of eight bright unobscured (at least at the iron line energy) Seyfert Galaxies observed simultaneously by XMM-Newton and BeppoSAX, taking advantage of the complementary characteristics of the two missions. The main…

Astrophysics · Physics 2009-11-10 S. Bianchi , G. Matt , I. Balestra , M. Guainazzi , G. C. Perola

We present a spectral variability study of the XMM-Newton and Suzaku observations of one of the most extreme Narrow Line Seyfert 1 galaxies, IRAS13224-3809. The X-ray spectrum is characterized by two main peculiar features, i) a strong soft…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 G. Ponti , L. C. Gallo , A. C. Fabian , G. Miniutti , A. Zoghbi , P. Uttley , R. R. Ross , R. V. Vasudevan , Y. Tanaka , W. N. Brandt

We present our analysis of the X-ray variability of two ultraluminous X-ray sources (ULXs) based on multiple XMM--Newton observations. We show the linear rms-flux relation is present in eight observations of NGC5408 X-1 and also in three…

High Energy Astrophysical Phenomena · Physics 2015-09-16 L. Hernández-García , S. Vaughan , T. P. Roberts , M. Middleton

The narrow-line Seyfert 1 galaxy Markarian 766 was observed for 60 ks with the XMM-Newton observatory. The source shows a complex X-ray spectrum. The 2-10 keV spectrum can be adequately represented by a power law and broad Fe Ka emission.…

We present spin-resolved X-ray data of the neutron star binary Her X-1 taken using the EPIC detectors on XMM-Newton. The data were taken at three distinct epochs through the 35 day precession period. The energy dependent light curves of…

Astrophysics · Physics 2009-11-07 Gavin Ramsay , Silvia Zane , Mario Jimenez-Garate , Jan-Willem den Herder , C. Hailey

A ROSAT observation of the narrow-line Fe II QSO PHL 1092 shows rapid variability that requires an efficiency of at least 0.13, exceeding the theoretical maximum for an accretion disk around a non-rotating black hole. Plausible explanations…

Astrophysics · Physics 2009-10-28 Karl Forster , Jules P. Halpern

The LINER nucleus of the nearby spiral galaxy M81 was pointed by BeppoSAX, which caught it at the highest (2-10) keV flux level observed so far. The LECS, MECS and PDS data, extending over (0.1-100) keV, are used to investigate the physical…

Astrophysics · Physics 2007-05-23 S. Pellegrini , M. Cappi , L. Bassani , G. Malaguti , G. G. C. Palumbo , M. Persic

Narrow Line Seyfert 1 galaxies are generally accreting at high fractions of the Eddington limit. They can show complex X-ray spectra, with a strong `soft excess' below 2 keV and a sharp drop at ~7 keV. There is strong evidence linking the…

Astrophysics · Physics 2008-11-26 C. Done , M. A. Sobolewska , Marek Gierlinski , N. J. Schurch

We report on a long X-ray observation of the slow-rotating binary pulsar GX 1+4. BeppoSAX observed, in the 0.1-200 keV energy range, an event in which the source flux dropped for almost a day, and then recovered. During this event only the…

In the recent literature on AGNs it has been often reported that spectra of Seyfert 1 Galaxies show resonant absorption lines of Fe K which are redshifted from the rest frame position. Such lines are often found with marginal significance…

Astrophysics · Physics 2007-05-23 A. L. Longinotti , S. Sim , K. Nandra , P. O'Neill , M. Cappi

We have analyzed the two longest (elapsed time > 3 days) BeppoSAX observations of the X-ray brightest Seyfert galaxy, NGC 4151, to search for spectral variability on time-scales from a few tens of ksec to years. We found in both cases…

Astrophysics · Physics 2008-11-26 S. Puccetti , F. Fiore , G. Risaliti , M. Capalbi , M. Elvis , F. Nicastro , .

This paper presents ASCA (July 1997), XMM-Newton (December 2000) and BeppoSAX (January 2001) observations of the Piccinotti Seyfert 1 galaxy ESO198-G24. The BeppoSAX 0.1-200 keV spectrum exhibits reprocessing features, probably produced by…

Astrophysics · Physics 2009-11-07 M. Guainazzi

We present results from two XMM-Newton observations of the bright classical Seyfert 2 galaxy NGC 7582 taken four years apart (2001 May and 2005 April). We present the analysis of the high-resolution (0.3-1 keV) RGS and low-resolution…

Astrophysics · Physics 2009-11-13 E. Piconcelli , S. Bianchi , M. Guainazzi , F. Fiore , M. Chiaberge

Aims. X1908+075 is a supergiant X-ray binary (SgXB) composed of an evolved OB star and a neutron star (NS) in a 4.4-day orbit. We aim to characterize the stellar wind, constrain the system geometry, and investigate the origin and…

High Energy Astrophysical Phenomena · Physics 2026-05-19 J. Planelles-Villalva , J. M. Torrejón , J. J. Rodes-Roca , G. Sanjurjo-Ferrín

The observational evidence for AGN relativistic Iron lines is very much debated. To address this topic, the FERO project makes use of the largest sample of X-ray spectra of radio quiet Type 1 AGN available in the XMM-Newton archive. We…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-11 Anna Lia Longinotti , Ignacio de la Calle Perez

We present the results of X-ray spectral-timing analysis of a 90ks XMM-Newton observation of the nearby, broad line, early-type AGN NGC5273. The X-ray spectrum revealed the clear presence of a reflection component at high energies, with a…

High Energy Astrophysical Phenomena · Physics 2020-01-08 F. M. Vincentelli , G. Mastroserio , I. Mc Hardy , A. Ingram , M. Pahari
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