Ambient-temperature limit of an adiabatic blast wave ($T_d\propto t^{-6/5}$)

A monatomic strong shock has $T_d=3\bar{m}{V}_s^2/(16k_B)$. Together with the Sedov-Taylor blast wave radius this gives $T_d\propto t^{-6/5}$. Extrapolating to ambient temperature or sonic speed estimates when the cold-upstream assumption fails, but the strong-shock law is already becoming inaccurate there. Radiative cooling can end the energy-conserving stage earlier; its transition age additionally needs a cooling function and composition.