Abstract

We report rate coefficients for electronic quenching of NO (A²∑⁺) by N₂, Ar, and NO (X²∏) measured at room temperature and behind incident and reflected shock waves (900 K to 4500 K). The N₂ quenching cross-section increases dramatically from 0.007 Ų at 296 K to 7 Ų at 4500 K. Modeling based on an ion-pair intermediate for the collision accurately predicts the increase in N₂ cross-section up to 2300 K and suggests that additional mechanisms become important at higher temperatures. We also use simultaneous measurements of dispersed fluorescence spectra and fluorescence decay rates from v' = 0 and v' = 1 to obtain vibrational energy transfer rates in A²∑⁺ at 1900 K.

© 1992 Optical Society of America