Unveiling the distribution of absorption in the AGN population
  We use the very deep XMM-Newton observations in the CDF-S to measure the distribution of absorption in the AGN population. We describe the Monte Carlo method used to unveil the intrinsic properties of the AGN using their multi-band X-ray colours. The measured distribution of AGN in z, L_X and N_H space is compared with the distributions predicted by a number of XLFs and absorption models. In contrast to other studies, we do not find any evidence that the absorption distribution is dependent on redshift or intrinsic luminosity. 
Tom Dwelly, Mathew J. Page