Properties of the COSMOS QSO working sample (duplicates resolved). a) Redshift distribution of the sample: all QSOs (black) and for each individual dataset, colored according to the key in the upper-left corner. b) AGN bolometric luminosity against redshift. The solid lines show the limiting L_bol set by the I_AB = 22.5 and B_AB = 25 depths of the zCOSMOS Bright and Deep surveys, respectively. c) Black hole mass (M_BH) against redshift. The solid lines show the limiting M_BH set by the limiting magnitude of the zCOSMOS datasets for SMBHs with broad-line FWHM = 1500 km s^-1. d) Eddington ratio (λ_E) against redshift. Lines show the λ_E limits set by the limiting magnitude of the zCOSMOS datasets, for two different broad-line FWHM: 1500 km s^-1 (solid) and 8000 km s^-1 (dashed). The points and limit lines in the all panels are colored by dataset according to the key in panel a). The bins used to divide the sample by redshift and M_BH, L_bol, and λ_E are shown as dotted lines in the respective panels. Objects in each binned subsample were stacked together in the Herschel/PACS maps to derive mean FIR luminosities for the bin.