Radial velocity dispersion profiles as a function of radius for models with an IMBH mass 2% of the stellar mass with the same initial r_hp. Observational data are shown as red points, and a sample uncertainty is shown in blue as in Fig. 1. Black, magenta, light blue, green and orange points are models with initial c = 0.4 to 0.8. All models have the same dispersion outside the core radius (~100′′) while clusters with higher concentration show higher velocity dispersion towards the center, as explained in Sect. 4.