Fitted values of spike radius |$r_\text{sp}$| of equation (12) for a |$10^4 \,\text{M}_\odot$| halo and a |$10^3\, \text{M}_\odot$| BH grown over 4 Gyr. Every line represents a different value of |$r_\text{conv}$| during fitting, where |$r_\text{conv} = \delta \epsilon$|⁠, and |$\epsilon$| is the gravitational softening of equation (9). The plot has been zoomed in for visual clarity.