Microscopic description of our hierarchical fragmentation model. Left: fragmentation procedure of a single parent contained in a multi-scale structure of size R₀. Any parent at a level l, of scale R_l and mass M_l, can be selected in order to evaluate the number n_l of fragments it produces and then determine the fraction of its mass ϵ_lψ_l,i·distributed to the i-th child. The size of the arrow represents the amount of mass inherited by a child. Right: parent’s probability p_l(n_l) to produce n_l children before transferring a proportion ϵ_lψ_l,i of its mass to each of its children.