Transient-Spark Discharge in $\hbox{N}_{2}/\hbox{CO}_{2}/\hbox{H}_{2} \hbox{O}$ Mixtures at Atmospheric Pressure

Transient spark, which is a novel type of streamer- to-spark transition discharge, was investigated in N
₂
/CO
₂
/H
₂
O mixtures. It has a pulsed character with short (~100 ns) pulses of high current amplitude (~1 A) with repetitive frequencies of some kilohertz, and it generates nonequilibrium plasma. Emissions of N
₂
first and second positive systems, CN violet system, NH, and atomic N, O, and C lines were detected. Two distinct discharge modes at low and high frequencies with different properties were found.