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Inferring the coronal flaring patterns in AGN from reverberation maps

R. Goyder·A. N. Lasenby
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Abstract

The relativistically broadened iron K-alpha line at 6.4 keV observed in the Seyfert 1 galaxy MCG-6-30-15 has provided a probe of the strong-gravity environment near a black hole, in particular suggesting that it is rapidly spinning. An important variable in such analyses is the geometry of the illuminating source. We present a new technique which constrains this geometry based on the spectral line shape, based on a model of discrete, point-like flaring regions in the X-ray corona. We apply it to simulated reverberation maps and give examples of successful reconstructions of complex coronal flaring patterns. For time-averaged spectral lines the problem is highly degenerate, and so its inversion more challenging. We quantify this degeneracy and give a measure of the spatial accuracy of the method in this case, before checking that it is consistent with the existing picture of MCG-6-30-15 by applying it to recent data from XMM-Newton.

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R. Goyder, A. N. Lasenby. 2003-09-20. Inferring the coronal flaring patterns in AGN from reverberation maps. https://doi.org/10.1111/j.1365-2966.2004.08071.x

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