Time and wavelength resolved measurements of the VUV excimer emission generated in a windowless dielectric barrier discharge (DBD) in argon

Temporal analysis of the VUV emission from a windowless dielectric barrier discharge [1] in pure argon from 50-800 mbar were carried out to gain insight into the underlying kinetic processes relating to the first and second continuum emission bands of the Ar$_{2}$* excimer. Pulsed excitation using bi-polar voltage pulses with 2{\%} duty-cycle and 32kHz repetition frequency were employed to achieve a uniform discharge with well-controlled electrical breakdown characteristics. By comprehensively measuring the rising and decay time constants for $\sim $50 individual wavelengths within the first and second continuum of argon covering the range $\lambda $=107nm-140nm, the dominant collisional and radiative rates relating to Ar$_{2}$* excimer production and loss have been obtained. The variation of time constants as a function of wavelength and gas pressure has been determined. The VUV emission curves at the transition phase between the first and second continuum have been analyzed in detail. [1] R J Carman et al., J.Phys.D:Appl.Phys, 43, 025205 (2010).