Sedov explosion for models S₄ and S₈ in Table 5. Top row: density profiles at t = 0.09 calculated with X_a = m_a (model S₄, standard VEs) and (model S₈, improved VEs). The black line is the analytical solution. Note that the spherical symmetry is well preserved in both cases and that the density peak is very well reproduced with the improved VEs. Bottom row: same but with the partition of unit. All particles are represented in the plots.