Profiles of the spherical and cylindrical models. Model 𝒢 has a Gaussian shape, whereas the power-law models Ƥ_A, Ƥ_B, Ƥ_C, and Ƥ_D have extended envelopes outside their Gaussian core, with the volume densities ρ ∝ r^−α and intensities I ∝ θ^−β (Table 1). The profiles, differing in intensity (density) by a factor of 3, fall off steeply at the outer boundary Θ = 64″ because of the adopted geometry of the finite models. The dashed profiles correspond to the “infinite” models (no outer edge within the entire image area), discussed in Sect. 4.6.