Fraction of star forming galaxies as a function of cluster-centric distance in simulated clusters and in A963. Thin lines of different colour represent galaxies quenched with a delay after their crossing of R₂₀₀ of the parent cluster, according to the colour bar at the top of the figure. The data for A963 are shown in black (symbols and line). The f_SF values calculated for individual galaxies are shown as black points, and the mean f_SF values within each Voronoi bin are shown as empty squares. The dashed line shows a third-order polynomial fit to the Voronoi bins. For clarity, a small horizontal offset has been added to the black points.