Metastable fragment production following electron impact on CO2

An apparatus is described which is suitable for studying dissociative excitation of molecules into metastable fragments and results are presented for electron impact on CO 2 . Both Rydberg and non-Rydberg contributions have been observed in the resultant fragments. Among the processes which are probably being observed are those which yield the following fragments, CO(X 1 Sigma g + )+O(HR), CO(a 3 Pi )+O( 5 S), CO(a 3 Pi )+O(HR) and C( 3 P)+O( 5 S)+O(HR). The results are compared with those of other workers.