Energetic Ions from N2 Produced by Electron Impact

Energy distributions, appearance potentials, and angular distributions of N+ ions produced by electron impact on N2 have been observed. The energy distribution and appearance potential of the N+ + ions from electron impact on N2 were also observed. The data are interpreted to give the abundance of the ``zero-energy'' N+ and the N+ + ions. The appearance-potential data for the ``zero-energy'' N+ ions disagree with previous measurements, and a possible interpretation indicates that the conclusion of previous investigators that no excited ions are produced may not be valid.