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X-ray reprocessing in Seyfert Galaxies: simultaneous XMM-Newton/BeppoSAX observations

S. Bianchi·G. Matt·I. Balestra·M. Guainazzi·G. C. Perola
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Abstract

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 results of our analysis can be summarized as follows: narrow neutral iron lines are confirmed to be an ubiquitous component in Seyfert spectra; none of the analyzed sources shows unambiguously a broad relativistic iron line; all the sources of our sample (with a single exception) show the presence of a Compton reflection component; emission lines from ionized iron are observed in some sources; peculiar weak features around 5-6 keV (possibly arising from rotating spots on the accretion disk) are detected in two sources. The scenario emerging from these results strongly requires some corrections for the classical model of reprocessing from the accretion disk. As for materials farther away from the Black Hole, our results represent a positive test for the Unification Model, suggesting the presence of the torus in (almost) all sources, even if unobscured.

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S. Bianchi, G. Matt, I. Balestra, M. Guainazzi, G. C. Perola. 2004-04-15. X-ray reprocessing in Seyfert Galaxies: simultaneous XMM-Newton/BeppoSAX observations. https://doi.org/10.1051/0004-6361%3A20047128

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