The hard X-ray spectrum of Compton-thick Seyfert 2 galaxies and the synthesis of the XRB

Giorgio Matt; Fulvio Pompilio; Fabio La Franca

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arXiv · astro-ph/9912344

The hard X-ray spectrum of Compton-thick Seyfert 2 galaxies and the synthesis of the XRB

Giorgio Matt·Fulvio Pompilio·Fabio La Franca

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Abstract

A synthesis model for the cosmic X-ray Background (XRB) is presented, which includes a proper treatment of Compton scattering in the absorbing matter for type 2 AGN. Evidence for a decrease of the relative importance of type 2 AGN at high redshift is found, which may be due either to a decrease of the relative number of obscured sources, or (more plausibly) to an increase of the fraction of Compton-thick absorbed sources. The XRB spectrum, soft X-rays and hard X-rays source counts can be simultaneously fitted only if the XRB normalization as derived from BeppoSAX/MECS measurements is adopted.

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Giorgio Matt, Fulvio Pompilio, Fabio La Franca. 1999-12-16. The hard X-ray spectrum of Compton-thick Seyfert 2 galaxies and the synthesis of the XRB. https://arxiv.org/abs/astro-ph/9912344

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