Deactivation of CO(AΠ) in individual vibrational levels

Resonance absorption of CO(A¹Π → X¹Σ⁺) fourth positive bands was used to excite CO molecules selectively into the ν′ = 0 and ν′ = 1 vibrational levels of the A¹Π state. Studies of the fluorescence spectra at different added gas pressures yielded effective cross sections for the vibrational relaxation of A¹Π, ν′ = 1 and for the quenching of A¹π, ν′ = 0 molecules. Very large cross sections up to gas kinetic were measured for the rare gases He, Ne, Ar, and Kr as well as for the molecular species H₂, D₂ and N₂