Emision of Cl2* molecules in a barrier discharge

The energy and spectral parameters of emission of a barrier discharge in chlorine and its mixtures with inert gases are studied experimentally. The barrier discharge in chlorine was homogeneous at pressures up to ~9 Torr and its spectrum contained the ³Π_2g→³Π_2u, ³Π_2g→³Σ_2u⁺ and ¹Σ_u⁺→¹Σ_g⁺ bands of Cl₂* molecules. After the addition of an inert gas, the 257.8-nm ³Π_2g→³Π_2u band made the main contribution to the spectrum. The maximum efficiency and power of the Cl₂ excilamp were obtained for the chlorine — argon mixture and amounted to 0.7% and 1.3 W, respectively.