Spatially Resolved N-2(A(3)Sigma(+)(U), Nu=0) Decay Studies In The Pulsed Direct-Current Nitrogen Discharge Using The Laser-Induced-Fluorescence Technique

We focus on the investigation of the spatial distribution and temporal evolution of N-2(A(3)Sigma(+)(u), nu = 0) in a very early afterglow of a pulsed dc nitrogen discharge. The results indicate that a fast quenching process of N-2(A(3)Sigma(+)(u), nu = 0) exists in the very early afterglow. We study the dependence of this fast quenching process on the discharge pressure 20-40 torr. It seems that this fast quenching behavior of N-2(A(3)Sigma(+)(u), nu = 0) found in our experiment can be ascribed to the combined action of pooling reaction and collisions with N atoms through N-2(A(3)Sigma(+)(u))+N-2(A(3)Sigma(+)(u))-> N-2*+N-2(N-2*=N-2(B-3 Pi(g), C-3 Pi(u), C'(3) Pi(u), C "(5) Pi(u))) and N-2(A(3)Sigma(+)(u))+N(S-4)-> N(P-2)+N-2, respectively. Meanwhile, the decay studies of N-2(A(3)Sigma(+)(u), nu = 0) near the anode and cathode infer that the production of N(S-4) atoms does not distribute uniformly along the axis of the discharge gap at relatively low pressure, and this effect becomes gradually inconspicuous with the increasing discharge pressure.