Study of Some Electronic Transition Probabilities in CO and CN

The transition probabilities of the CO third positive (b 3Σ→a 3II), the CO Ångstrom (B 1Σ+→A 1II), and the CN violet (B 2Σ+→X 2Σ+) systems have been obtained from measurements of radiative lifetimes by the phase-shift method. In the CO Ångstrom system the probability of B 1Σ+→A 1II was distinguished from the (greater) probability for B 1Σ+→X 1Σ+ by taking advantage of reabsorption (or resonance trapping) of the shorter wavelength radiation. In the CN (B 2Σ+→X 2Σ+) transition there is found to be no measurable dependence of the electronic transition moment on internuclear distance.