Vibrational distributions of N2O+(Ã 2Σ+) produced by electron impact on jet‐cooled N2O

Fluorescence spectra of the N2O+(A 2Σ+–X 2Πi) system produced by electron impact on N2O have been studied in the impact energy range of 22–100 eV in order to determine vibrational‐state distributions of the N2O+(A 2Σ+) state. Emission bands from the 00, 21K1, 22K0, 11, 12, and 31 levels have been assigned. The populations of the 11 and 12 levels corrected for effects of predissociation are similar to those obtained by the threshold photoelectron method. It is concluded that these results are affected by autoionization via the Rydberg states converging to the C 2Σ+ ion state. The population of the 21K1 level is enhanced remarkably more than in photoionization data. This enhancement indicates that, in the electron impact, transitions with ΔK=±1 are allowed in the formation of A 2Σ+.