Quantitative absorption and fluorescence studies of CO from 1060 to 1550 AA

The photoabsorption cross section of CO has been measured in the 1060-1550 AA region using synchrotron radiation. The oscillator strengths for the transitions from CO(X 1 Sigma + ) to various excited states are obtained from these data. Fluorescence from excited CO was observed in the 1150-3000 and 3000-8000 AA regions. The quantum yields for the production of fluorescence from the A 1 Pi and b 1 Sigma + states are unity because their excitation energies are below the dissociation limit. The C 1 Sigma + , nu =0 level has significant fluorescence quantum yields both in the UV and visible regions, but the yields for the E 1 Pi , nu =0 and C 1 Sigma + , nu =1 levels are very small. The C 1 Sigma + , nu =1 level is presumably predissociated. The cross sections for the production of fluorescence from the a' 3 Sigma + , d 3 Delta i , e 3 Sigma - to a 3 Pi and B 1 Sigma + , C 1 Sigma + to A 1 Pi transitions upon excitation from the X 1 Sigma + have also been measured.