Dynamics of excitation of radiating shock waves in inert gases

An experimental study is made of the dynamics of formation of shock waves in inert gases at large Mach numbers (15-20). It is shown that the formation of a uniform flow behind the shock wave is impeded by radiative vaporization of the shock tube walls. The conditions for setting up experiments to study anomalous relaxation are discussed. An anomalously large delay in ionization relaxation is observed in argon and xenon in the initial stage of formation of a shock wave. It is proposed that inelastic atom-atom collisions make a smaller contribution to the seed density of electrons than supposed previously.