Measurement of { N}_2(A\,{}^3Σ^+ᵤ) metastable in N2pulsed positive corona discharge with trace amounts of additives

The density of metastable is measured in various gases (N 2 /O 2 , N 2 /NO, N 2 /NO 2 , N 2 /H 2 O, N 2 /CO) after pulsed positive corona discharge using time-resolved laser-induced fluorescence (LIF) under atmospheric pressure. The density in N 2 /O 2 (0.25%) is uniformly distributed along the axis of the discharge gap (point-to-plane, 12 mm). This result indicates that is mostly generated in the primary streamer channels. The absolute density is measured by calibrating the LIF signal intensity. When the discharge voltage is 21.5 kV, the density immediately after the discharge pulse is estimated to be (2–3) × 10 13 cm −3 . The reaction rate constants of with O 2 , NO, NO 2 , H 2 O and CO are roughly estimated using the decay rate of density after the discharge pulse, and are compared with reference values. production is increased approximately twofold when hundreds of ppm of O 2 , NO or NO 2 molecules are added to N 2 .