Density distributions for the ejecta rich in Fe (orange), Si (green), and O (blue) for the models with high explosion energy at different evolution times (increasing from top to bottom). The opaque irregular isosurfaces correspond to a value of density at 1% of the peak density in each case. The semi-transparent surface marks the position of the forward shock; the yellow semi-transparent surface barely visible in the top panels represents the position of the reverse shock. The orientation of the system is the same as G26 (see Fig. 2).