Dissociative electron attachment to metastable oxygen (a1Δg)

Dissociative attachment from metastable oxygen (a 1 Delta g ) has been studied with an electron impact spectrometer and a microwave discharge. Three processes are observed. The first dissociates to the first limit, has a cross section maximum of 3.8*10 -18 cm 2 at 6.5 eV with respect to the ground state and is a result of formation of the well known 2 Pi u resonance. The second dissociates at the second limit and is the consequence of a 2 Sigma g + resonance. The cross section is estimated to be 1.8*10 -18 cm 2 at its maximum which occurs at 8.5 eV above the ground state. The third is very weak (cross section maximum less than 10 -20 cm 2 at 9.5 eV above ground), dissociates to the third limit and 2 Sigma g + symmetry is proposed for the resonance.