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The contribution of AGNs to the X-ray background

A. Comastri·G. Setti·G. Zamorani·G. Hasinger
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Abstract

We report the results of a detailed analysis of the contribution of various classes of AGNs to the extragalactic X-ray background (XRB). The model is based on the unification schemes of AGNs and on their related X-ray spectral properties in the light of recent observational results. The integrated emission from AGNs, when folded with an appropriate cosmological evolution law, can provide a good fit to the XRB over a wide energy range, from several to $\sim$ 100 keV, while it contributes only about 74\% of the ROSAT soft XRB. The model predictions have been checked against all available observational constraints from both hard and soft X-ray surveys (counts, redshift distributions and average X-ray source spectral properties).

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A. Comastri, G. Setti, G. Zamorani, G. Hasinger. 1994-09-27. The contribution of AGNs to the X-ray background. https://arxiv.org/abs/astro-ph/9409067

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