We have studied the kinetics of the lowest excited singlet state of molecular nitrogen, N2(aprime;thinsp;1Sgr;minus;u,v=0), in a discharge flow reactor. The metastables were generated in a hollow cathode dc discharge through molecular nitrogen highly diluted in argon, and detected by VUV flourescence of the forbidden N2(aprime;thinsp;1Sgr;minus;undash;Xthinsp;1Sgr;+g) band system. Observations of the equilibrium between the N2(athinsp;1Pgr;g) and N2(aprime;thinsp;1Sgr;minus;u) states in our reactor indicate that the metastable has a radiative lifetime gsim;23+11minus;6ms, assuming a radiative lifetime of 80+40minus;20mgr;s for N2(athinsp;1Pgr;g). Rate coefficients for quenching by NO, CH4, CO, and N2O are approximately gas kinetic, those by H2, O2, and CO2roughly tenth gas kinetic, and that by molecular nitrogen (1.9plusmn;0.5)times;10minus;13cm3thinsp;moleculeminus;1thinsp;sminus;1. The interaction between N2(aprime;) and CO produced CO(Athinsp;1Pgr;ndash;Xthinsp;1Sgr;) emission in about 21+10minus;8percnt; of the quenching events.
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