Saha-boltzmann statistics for determination of electron temperature and density in spark discharges using an echelle/CCD system

A custom echelle/CCD spectrometer system has been employed for equilibrium and nonequilibrium excitation measurements in the high-voltage spark discharge. By exploitation of the large spectral information bandwidth of the echelle/CCD system, multiple ionization stages of argon were observed in the spark emission spectrum. Ion-to-atom emission intensity ratios were used in a linearized form of the coupled Saha- Boltzmann equation for the determination of both electron temperature and density. Nonequilibrium conditions were considered. The dependence of argon excitation on sample matrix was also explored.