Spectroscopic study of high-Mach-number air shock layers generated by a ballistic range

Spectroscopic studies on high-Mach-number air shock layers generated by a ballistic range have been conducted. Using a spectrograph and a highly-sensitive film system, spectrograms of the shock layer at flight velocities higher than 3 km/sec were taken. These photographic data were transformed into numerical data using a digital data-processing system composed of a CCD camera and an image processor. In the wavelength range from 350 nm to 440 nm, several band spectra of N₂ and CN were observed. In order to investigate the contributions of the respective species on the radiative emission, a high-speed shuttering system using an image intensifier, along with highly-sensitive film, has been set-up.