Production mechanism of atomic nitrogen in atmospheric pressure pulsed corona discharge measured using two-photon absorption laser-induced fluorescence

To study the production mechanism of atomic nitrogen, the temporal profile and spatial distribution of atomic nitrogen are measured in atmospheric pressure pulsed positive corona discharge using two-photon absorption laser-induced fluorescence. The absolute atomic nitrogen density in the streamer filaments is estimated from decay rate of atomic nitrogen in N-2 discharge. The results indicate that the absolute atomic nitrogen density is approximately constant against discharge energy. When the discharge voltage is 21.5 kV, production yield of atomic nitrogen produced by an N-2 discharge pulse is estimated to be 2.9 - 9.8 x 10(13) atoms and the energy efficiency of atomic nitrogen production is estimated to be about 1.8 - 6.1 x 10(16) atoms/J. The energy efficiency of atomic nitrogen production in N-2 discharge is constant against the discharge energy, while that in N-2/O-2 discharge increases with discharge energy. In the N-2/O-2 discharge, two-step process of N-2 dissociation plays significant role for atomic nitrogen production. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4722317]