Transition probabilities in OH A(2)Sigma(+)-X(2)Pi(i): Bands with v'=2 and 3

Experimental relative vibrational band emission coefficients have been measured in the A (2) Sigma(+)-X (II)-I-2 electronic system of the OH radical. Branching ratios for the sequences v'=2, v '' = 0-5 and v'=3, v '' = 0-6 were determined using laser-induced fluorescence in a low pressure methane-oxygen flame. We accounted for potential error contributed by rotational and vibrational energy transfer and fluorescence polarization. These transition probabilities complete a set of experimental data, which are used in a separate study to determine the optimum electronic transition moment of the OH A -X system. (C) 1997 American Institute of Physics.