KINETICS OF THE (A(3)SIGMA(U)-2 IN THE NEAR AFTERGLOW OF A NITROGEN PULSED DISCHARGE(, V=0) STATE OF N)

The absolute densities of the nitrogen metastable molecules N2(A3SIGMA (u)+, v = 0) were measured as a function of time using a high resoluti on laser absorption within the first positive system (B3PI(g)(v' = 2) <-- A3SIGMA(u)+(v'' = 0)) in a stationary afterglow of the pure nitrog en pulsed electric discharge. The experiments were performed at variou s pressures (0.25-1.25 Torr), discharge currents (0.4-1.3 A) and pulse lengths (5-30 mus). The lifetimes and populations are in the range 10 0-470 mus and (0.3-2.7) x 10(12) cm-3 respectively. The postulated kin etic model describes the measured lifetimes within an experimental err or. The model takes into consideration the loss of N2(A) metastables d ue to energy pooling, quenching by nitrogen atoms and diffusion to the walls. Calculations of dissociation rates and nitrogen atom densities are based on the vibrational excitation of the ground electronic stat e N2(X).