Diagnostics of Pulsed Powered Microplasma Discharge in N$_{2}$ by Emission Spectroscopy

The aim of this paper is to analyze the emission spectrum of the microplasma, which is atmospheric pressure nonthermal plasma, generated by a pulse power supply in nitrogen gas. Microplasma discharge in N$_{2,}$ generated at relatively low discharge voltages around 1 kV, was investigated with an ICCD camera, a spectrometer and a photomultiplier tube. A Marx Generator with MOSFET switches was developed and used as a pulse power supply. It has a negative output up to -- 2 kV, rise time 100 ns, pulse width 1 us. Discharge current was confirmed at rising point of discharge voltage. About -2.5 A was obtained at -1.5 kV for negative pulse. Emission spectrum showed N$_{2}$ Second Positive System band (N$_{2}$ SPS), N$_{2}^{+ }$First Negative System Band (N$_{2}^{+}$ FNS) and N$_{2}$ First Positive System band (N$_{2}$ FPS). Lifetime emission signal of N$_{2}$ SPS peak of 337.1 was about 60 ns. Temperature calculation showed that microplasma is non equilibrium plasma due to the inequality Te$>$Tvib$>$Trot.