An Atlas of the Intersystem Transitions of CO

Abstract

The forbidden triplet-singlet bands of CO, originating from the X 1Σ+(v = 0) level and involving the a'3Σ+, e3Σ-, and d3Δ states, can advantageously be used in view of their low oscillator strengths to measure large CO column densities when the allowed A 1Π(v) - X 1Σ+(0) bands are saturated. The line positions and intensities of 41 of these bands are tabulated up to j = 6 in the paper version and up to J = 33 in electronic form. These data were obtained using an improved model developed in a previous paper. When possible, the calculated results are compared to experimental or observed ones, both for line positions and for oscillator strengths. The measured band oscillator strengths average to 94% of the calculated ones. A large majority of the measured values (27 out of 35) are within ±15% of the calculated ones. Thus, in view of the experimental uncertainties, it appears that the current calculated set of oscillator strengths can safely be used for the analysis of future absorption spectra involving the CO intercombination bands.