Left: major (full lines) and minor (dashed lines) axis gradients of the potential as functions of R and z, respectively, for the true Evans model (red) and for the matched Vogelsberger model with c/a ≃ 0.776, R_s ≃ 4.9 kpc and log₁₀(M_1 kpc[M_⊙]) ≃ 7.69 (blue). Right: comparison of the isopotential contours for the true Evans model (red) and the matched Vogelsberger model (blue). For the purpose of this figure the zero-point of the potential is chosen here such that Φ_E = Φ_V at (R, z) = (1, 0) kpc. For each potential, contours are drawn at the positions where Φ has changed in steps of 50 km² s⁻². In the region from 0.7 up to 2 kpc the matched Vogelsberger model follows well the true Evans potential. For more inner radii the (cusped) Vogelsberger models cannot reproduce the (less steep) cored behaviour of the Evans potential.