Molecular beam studies of collisional autoionization processes

The general features of collisional autoionization reactions involving metastable rare gas atoms studied in recent years are outlined. Atom-molecule autoionization processes can be seen as the result of two "half-collision" events: the autoionization of the neutral collision complex and the following dynamics of the ionic products. The Ne*+N2 system is discussed in terms of the vibrational predissociation which occurs in the Ne−N2+ product ion. The results for the collisional autoionization of H2, D2, and HD by Ne* are presented and discussed from the point of view of the "post-ionization" ion-molecule reaction. Finally, involvements of these processes in some plasma applications are discussed.