VUV emission from a cylindrical dielectric barrier discharge in Ar and in Ar/N₂ and Ar/air mixtures

The vacuum ultraviolet (VUV) emissions from a cylindrical dielectric barrier discharge (C-DBD) excited by radio frequency (rf) power at 13.56 MHz in both pure Ar and mixtures of Ar with N₂ and air were analysed. Measurements of the relative emission intensity of the excimer second continuum in pure argon were carried out as a function of pressure, rf power and gas flow rate. In Ar-N₂ and Ar-air mixtures, we studied the emission of the N I and O I atomic lines as a function of N₂/air concentration and total pressure. Channels of energy transfer from the argon metastables and excimers to atomic nitrogen and oxygen in excited Ar-N₂ (Ar-air) mixtures were analysed based on the dependence of the intensity of the VUV emissions on the discharge operating parameters and the gas mixture.