Top panels: relative positions of Fe-poor and Fe-rich RGB stars in ω Centauri and M22 with respect to the cluster center. Orange and cyan arrows indicate the average motion computed in each circular sector, as described in Section 4.2, scaled by a factor of 5 for clarity. The radial distances of the arrows correspond to the median radius of stars in each population. Bottom panels: ﹩{\rm{\Delta }}{\mu }_{\alpha }\cos \delta ﹩ and ﹩{\rm{\Delta }}{\mu }_{\delta }﹩ as a function of θ for the two analyzed clusters. The bottom left insets show the value of the r² parameter, which is indicative of the quality of the fit.