Absolute yields of CO(a′ 3Σ+, d 3Δi,e 3Σ−)+O from the dissociative recombination of CO2+ ions with electrons

Abstract

The flowing afterglow technique has been applied to the dissociative recombination CO2++e−→CO*+O, in order to determine the radiative cascade contribution from high-energy triplet states of CO, (a′ 3Σ+), (d 3Δi), and (e 3Σ−), to the total yield of the long-lived (a 3Π) state. The yields of the a′, d, e states were found to be approximately 18%, 20%, and 0.3%, respectively, of the total CO(a) yield, which leads us to conclude that (38±8)% of the total CO(a) yield is due to radiative cascading, rather than direct formation. When combined with our previously reported total CO(a) yield of 0.29±0.10, the absolute yields of the triplet states become f(a′)=0.053±0.024, f(d)=0.057±0.022, and f(e)∼9×10−4.