Ab initio calculation of the dipole transition moment and band oscillator strengths of the CO (A-X) transition

Band-integrated oscillator strengths of the CO A1Π− X1Σ+ transition for 0 ≤ v′ ≤ 23 and v′′ = 0− 1 have been calculated from an ab initio dipole transition moment given by highly correlated electronic wave functions. The calculations were carefully optimized to represent the dipole transition moment in the large range of internuclear distances necessary to describe correctly high vibrational levels. The computed oscillator strengths agree well with the more recent experimental data available for v′′ = 0. By comparing the present results with previous theoretical works, we estimate that the resulting line strengths for the higher v′ vibrational levels should be the most accurate to date.