Investigation of the coplanar barrier discharge in synthetic air at atmospheric pressure by cross-correlation spectroscopy

The barrier discharge in the coplanar arrangement operating in a single-filament mode was studied spectroscopically. The evolution of the discharge luminosity was measured by the technique of cross-correlation spectroscopy. The 1D-spatially and temporally resolved luminosities of the first negative (at 391.5 nm) and the second positive (at 337.1 nm) system of molecular nitrogen were recorded using the above-mentioned technique. A cathode-directed ionizing wave (IW) was clearly seen on the plot for radiation intensity at 337.1 nm. In addition to this, also observed was a wave of the enhanced electric field propagating over the anode. In this paper, the propagation of these waves is described and their velocities are determined. The discharge evolution is divided into three phases-the Townsend phase, the phase of the IWs propagation and the extinction phase. Since the above-mentioned luminosity distributions could be interpreted approximately as the electric field (for 391.5 nm) and the electron density (for 337.1 nm) distribution, the qualitative description of the discharge is made accordingly. All these parameters are compared with similar measurements of the volume discharge. Apart from this, an attempt to determine the reduced electric field is made according to the kinetic model.