ELECTRON-DENSITY PROFILES IN SINGLE SPARK DISCHARGES

Quadratic Stark broadening of Ar(I) emission lines was used to measure the spatial distribution of the electron concentration in individual high voltage spark discharges. Corrections were made for ion broadening asymmetry and the instrument transfer function. Within the measurement uncertainty, the spatial distribution of the electron concentration did not vary from spark-to-spark. The uncertainty was limited by the imprecision in knowledge of the electron temperature, which was estimated using a LTE model.