NITROGEN ATOM RECOMBINATION IN HIGH-PRESSURE AR-N2 FLOWING POSTDISCHARGES

The afterglow resulting from the nitrogen atom recombination in a flowing Ar-N2 microwave discharge (915 MHz and 100 W) is characterized by the first positive emission from N2(B, V'). This emission occurs with a vibrational enhancement which is shifted from V' = 11 in pure nitrogen to V' = 8 in an Ar-2% N2 mixture. The N-N recombination rates producing N2(B, V') in Ar-x% N2 mixtures (x varies from 2-100%) were calculated from the measurement of the first positive emission intensity by spectrometry and the determination of the nitrogen atom concentration by a NO titration. Normalized values were obtained from previous published data in pure nitrogen.