A physical model for the hard X-ray background

  title={A physical model for the hard X-ray background},
  author={Richard J. Wilman and Andrew C. Fabian and P. E. J. Nulsen},
  journal={Monthly Notices of the Royal Astronomical Society},
We combine a semi-analytic galaxy formation model with a prescription for the obscured growth of massive black holes, to reproduce the hard X-ray background (XRB), the local 2–10 keV active galactic nuclei (AGN) luminosity function and the source counts, including recent Chandra results. The model also complies with constraints on the AGN contribution to the far-infrared and submillimetre backgrounds. The comoving density of luminous AGN in the unabsorbed rest-frame] in the model… 

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