Charge transfer and Penning ionization of N₂, CO, CO ₂, and H₂S in proton excited helium mixtures

In this work we report on studies of the kinetics of He-N₂ mixtures excited by a proton beam. The rate of charge transfer from both atomic and molecular helium ions to N₂ was studied using a time-resolved technique to measure the fluorescence of N₂⁺ (B ²Σ_u⁺→X²Σ _g). The population of N₂⁺(B ²Σ_u⁺) through a Penning ionization process from metastable helium atoms or molecules is observed, and the Penning ionization and charge transfer process which populates this state in a He-N ₂ laser is discussed. The charge transfer rate constants of He ⁺-CO, He⁺-CO₂, He⁺-H₂S, and He₂⁺-CO are also measured.