Metastable excitation measurements in CO and N₂by high-resolution electron impact, using a low work function detector

High-resolution electron impact has been used to measure the excitation functions of the metastable states in CO and N 2 . A low work function detector has been used and this has enabled the lowest metastable states of CO and N 2 , a 3 Pi and A 3 Sigma u + respectively, to be included in the measurements. This ability to observe the lowest-lying metastable states and the high sensitivity of the measurements has allowed much new structure to be observed in the metastable excitation functions of these molecules. The modified Rydberg formula has been used to obtain tentative classifications of the higher-lying resonances. The measurements also provide information about the shape of the total metastable cross sections in CO and N 2 .