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Variability of the Fe K line relativistic component in a sample of Seyfert 1 galaxies

B. De Marco·M. Cappi·M. Dadina·G. G. C. Palumbo
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Abstract

We present the analysis of X-ray spectral varability made on a sample of 7 Seyfert 1 bright galaxies, using XMM-Newton data. From the "XMM-Newton Science Archive" we selected those bright Seyfert 1 showing one or more prominent flares in their 2-10 keV light curves. For each of them we extracted spectra in 3 different time intervals: before, during and after the flare. We fitted them with a simple power law and then shifted a narrow emission and absorption line template across the 2.5-10 keV data, in order to investigate the presence of line-like features with a confidence level greater than 99%. Some highly significant features were detected in 3 out of 7 sources studied. In particular, the 3 sources, namely PG 1211+143, NGC 4051 and NGC 3783, showed the presence of a variable emission feature in the 4.5-5.8 keV band, characterized by an increase of its intensity after the flare peak. Because of the observed variability pattern, this feature seems to be ascribable to a reverbered redshifted relativistic component of the Fe K line.

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B. De Marco, M. Cappi, M. Dadina, G. G. C. Palumbo. 2006-10-30. Variability of the Fe K line relativistic component in a sample of Seyfert 1 galaxies. https://doi.org/10.1002/asna.200610686

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