No abstract

One and two dye lasers have been used in an optical--{)ptical double resonance (OODR) study of the excited B In and C I~+ states as well as the low-lying, long-lived A' In and a 3n l electronic states of BaO. C I ~ + (v = 0) is shown to be the upper level in the v' = 0 progression of the Parkinson band system. Intensity anomalies in C I ~ + -x I ~ + emission, due to an interference effect between parallel and perpendicular transition amplitudes, have proved to be a sensitive indication of ~n = ± I perturbations.Emission from C I~+, which is populated by absorption of two photons via a real intermediate A I~+ vibronic level, into A' In (v =0,1, and 2) and a 3n l (v =0,1, and 2) has been observed. A scheme is presented by which the relative populations of the A' In and a 3n "reservoir states" could be monitored.