Upper left panel: binned velocity distribution of the spectroscopic members, compared to Gaussians with dispersion obtained through the biweight estimate (red) and considering the jackknife uncertainties (blue and green). All distributions are normalized to 1.0. Upper right panel: cumulative velocity distributions, color code as in the left panel. Lower panel: observed color–magnitude diagram of GN 5 of all spectroscopic (black circles) and photometric (crosses) members of the cluster within 1 Mpc from the center.