Testing current synthesis models of the X-ray background

R. Gilli; M. Salvati; G. Hasinger

doi:10.1051/0004-6361:20000105

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arXiv · astro-ph/0011341

Testing current synthesis models of the X-ray background

R. Gilli·M. Salvati·G. Hasinger

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Abstract

We present synthesis models of the X-ray background where the available X-ray observational constraints are used to derive information on the AGN population properties. We show the need for luminous X-ray absorbed AGNs, the QSO2s, in reproducing the 2-10 keV source counts at relatively bright fluxes. We compare a model where the evolution of absorbed AGNs is faster than that of unabsorbed ones, with a standard model where absorbed and unabsorbed AGNs evolve at the same rate. It is found that an increase by a factor of ~2 from z=0 to z~1.3 in the ratio between absorbed and unabsorbed AGNs would provide a significant improvement in the data description. Finally, we make predictions on the AGNs to be observed in deep X-ray surveys which contain information on the AGN space density at high redshift.

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BibTeX RIS

R. Gilli, M. Salvati, G. Hasinger. 2000-11-17. Testing current synthesis models of the X-ray background. https://doi.org/10.1051/0004-6361%3A20000105

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