Time evolution of hydrodynamical values for B12 ﹩\beta ﹩ 1.00 (prompt; left) and B11 ﹩\beta ﹩ 0.25 (delayed; right). Each panel includes the temperature in K (top), density in g ﹩{\mathrm{cm}}^{-3}﹩ (medium), and radius in km (low) for selected tracer particles. The condition for the NSE (T ∼ 9 GK) and the boundary of the neutrino-sphere are highlighted.