Discrete Source Synthesis of the X-Ray Background

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چکیده ندارد.

X-ray background synthesis: the infrared connection

We present a synthesis model of the X-ray background based on the cross-correlation between mid-infrared and X-ray surveys, where the distribution of type 2 sources is assumed to follow that of luminous infrared galaxies while type 1 sources are traced by the observed ROSAT distribution. The best fits to both the X-ray number counts and background spectrum require at least some density evolutio...

Testing current synthesis models of the X–ray background

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,...

The X–ray Background: Observations

The X-ray Background and the Deep X-ray Surveys

The deep X-ray surveys performed by the two major X-ray observatories on flight, Chandra and XMM, are being resolving the bulk of the cosmic X-ray background (XRB) in the 2–10 keV energy band, where the sky flux is dominated by extragalactic emission. Although the actual fraction depends on the absolute sky flux, which is measured with an uncertainty of ∼ 40%, most of the XRB is already resolve...