抄録
The Ionization relaxation and radiative-cooling processes behind shock wave in xenon with or without a small amount of hydrogen have been investigated using a quadrature interferometer technique at shock Mach numbers Ms∼13 and the initial pressure P1=2.0 Torr. By adding a small amount of hydrogen (∼0.5% of the initial pressure) to xenon, the ionization relaxation time was drastically reduced to about one-third of its pure xenon value. From the comparison between theoretical values based on the two-step ionization model and experimental data, the slope constants of excitational cross-section against relative kinetic energy between xenon atom-atom collisions and xenon-hydrogen atom-atom collisions were determined to be 1.8×10−19 cm2/eV and 9.0×10−19 cm2/eV, respectively.
