Significant detected galaxy concentrations (SDGC) around one cluster when considering magnitude interval I within a 2.5 Mpc radius from the cluster centre (see text). This figure shows the number of galaxies in a  ±0.05 photometric redshift bin around the considered cluster as a function of the sector number. Filled red circles: SDGC detected by SExtractor together with their 1σ level extension. The definition of the angular sector is given in the text.