ROLE OF N-2(A' (5)SIGMA(G)(-PI(G)(V=10) POPULATIONS IN THE AFTERGLOW()) IN THE ENHANCEMENT OF N2B3)

Time-resolved spectroscopic observations of the N-2 1PG afterglow, b(3 )II(g)-->A (3) Sigma(u)(+), following a pulsed discharge show both an enhancement in the overall intensity and significant changes the shape of bands which arise from the v = 10 level of the B (IIg)-I-3. Model results indicated that these changes in shape are produced by an enhan cement of the population of the low J levels Omega=2 component of the v = 10 level. In addition, we also observed bands of the Herman Infrar ed system of N-2 (HIR), C'' (IIu)-I-5-->A' (5) Sigma(g)(+), specifical ly the (3,1) and (2,0) bands. During the afterglow, both the 1PG and H IR are being produced by energy pooling processes. The time-dependent increase of the 1PG v'= 10 band intensities show a strong correlation with the variation in the HIR band intensities which predominately pop ulate the lower levels of the A' (5) Sigma(g)(+). Recent work has show n the A' (5) Sigma(g)(+) to have a significantly deeper potential well than previously thought so that it is now thought to cross the B (IIg )-I-3. Based on our measurements and a simple model of the afterglow w e have estimated the apparent rate coefficient for collisional transfe r between A' (5) Sigma(g)(+) and the high v levels of the B (IIg)-I-3 due to collisions with the N-2 ground state. The value for collisional transfer from A' to B is approximately 1.0X10(-11) cc/molecule s. Our observations indicate the A' (5) Sigma(g)(+) may have an even deeper potential and we estimate an upper bound for v = 0 to be similar to 35 90+/-32 cm(-1) below the dissociation limit which is similar to 500+/- 32 cm(-1) deeper than the recent theoretical estimate.