Collisional broadening of the A2Σ+←X2Π(0,0) band of OH by H2O and CO2 in atmospheric-pressure flames

Abstract Absorption lineshapes of OH found in hot post-flame gases were measured using a rapid-tuning single-mode laser. Collisional linewidths due to broadening by H 2 O and CO 2 were determined by fitting the observed lineshapes to standardized Voigt profiles. Lines corresponding to transitions with ground-state angular momentum quantum numbers ( J ″-values) ranging from 1.5 to 17.5 in the R 1 -branch of the A 2 Σ + ← X 2 Π (0,0) band near 307 nm were probed. The temperature-dependence of collisional broadening was investigated over the range 1470–2370 K.

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