Radiative efficiency – Eq. (14) – (top panel) and radius of the innermost stable circular orbit – Eq. (11) – (bottom panel), as a function of the BH dimensionless spin parameter. Some reference values of these quantities are also highlighted: a = −1, for a counter-rotating orbit around a maximally spinning BH; a = 0, for a non-spinning BH; a = 0.998, for the maximum spin allowed in our simulations.