Reflection at large distance from the central engine in Seyferts

J. Malzac; P. O. Petrucci

doi:10.1046/j.1365-8711.2002.05851.x

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arXiv · astro-ph/0109339

Reflection at large distance from the central engine in Seyferts

J. Malzac·P. O. Petrucci

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Abstract

We consider the possibility that most of the reflection component, observed in the hard X-ray spectra of Seyfert galaxies, could be formed on an extended medium, at large distance from the central source of primary radiation (e.g. on a torus). Then, the reflector cannot respond to the rapid fluctuations of the primary source. The observed reflected flux is controlled by the time-averaged primary spectrum rather than the instantaneous (observed) one. We show that this effect strongly influence the spectral fits parameters derived under the assumption of a reflection component consistent with the primary radiation. We find that a pivoting primary power-law spectrum with a nearly constant Comptonised luminosity may account for the reported correlation between the reflection amplitude $R$ and the spectral index $Γ$.

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J. Malzac, P. O. Petrucci. 2001-09-20. Reflection at large distance from the central engine in Seyferts. https://doi.org/10.1046/j.1365-8711.2002.05851.x

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