Evolution of AGNs and a model of the X-ray back-ground Original Research Article

Based on a new estimate of the soft (0.5-2 keV) X-ray luminosity function (SXLF) from ROSAT surveys, we have constructed a population synthesis model from unabsorbed “type 1” and absorbed “type 2” AGNs. We present one of the models we have explored, which currently best represents observational data. As a new feature, we have included a possible absorption-luminosity correlation in our model. We have found a model which reasonably reproduces: (1) the 0.5-2 keV full luminosity function of AGNs (2) the LogN −LogS functions in 0.5-2 keV, 2–10 keV and 5–10 keV bands. (3) the total CXRB intensity over 1–100 keV.