behaviour in a N2NO surface dielectric barrier discharge in the modulated ac regime at atmospheric pressure

International audienceOptical, electrical and discharge product measurements were performed in order to reveal the behaviour of N 2 (A 3 Σ u +) metastables in a surface dielectric barrier discharge driven in N 2 with small NO admixtures in a modulated AC regime. Metastable species were detected both in a thin surface plasma layer and in the space afterglow through Plasma Induced Emission and Optical-Optical Double Resonance Laser Induced Fluorescence, respectively. Basically, the observed N 2 (A 3 Σ u +) species follow the discharge current oscillations in the plasma layer, while they evolve on a millisecond time-scale due to diffusion through the space afterglow. Emission spectrometry provides a rough estimation of average metastable concentration in a thin surface plasma layer ∼ 9×10 13 cm -3. Fluorescence measurements then allow an upper estimation of metastable concentration in the space afterglow ≤ 1×10 12 cm -3. Short title: N 2 (A 3 Σ u +) behaviour in surface DBD