Mass spectrum of the substructures for the two simulations. Top panel: mass spectrum of the bound structures in the zoom (α_vir <  2). The pink histogram and fit are obtained for a detection performed on the edge-on density map. The power slopes are parametrised by dN/dM ∝ M^−β. Bottom panel: evolution of the slope of the power-law fit to the high-mass end of the mass spectrum. The dashed grey line shows the location of the −1.8 exponent.