Histograms of the radio–optical angle (Ψ, left) and apparent offset (d_app, right) for the set of randomized synthetic emission maps. Each row represents histograms for a given average mass-loading Q₀ and for a given star distribution (r_c,s= 1.0 kpc in blue and r_c,s = 1.5 kpc in red; dark blue represents the overlap). Vertical dashed lines in the panels of the right column represent the associated median radio–optical offset.