Selection in CC space. Upper panel: CC diagram for PLCK G100 galaxies. Cluster members are shown with orange dots, and foreground and background galaxies with green and magenta dots, respectively. Unclassified sources are plotted with black dots. Bottom panel: radial number density profiles of galaxies. The background density profile (magenta squares) shows a decrease in the central region; overplotted is the magnification effect expected for a NFW profile.