COLLISION-ENERGY ELECTRON-ENERGY RESOLVED 2-DIMENSIONAL STUDY OF PENNING IONIZATION OF AR BY HE METASTABLE ATOMS 2(3)S AND 2(1)S/

Selection of collision energies by a time-of-flight method has been co mbined with Penning ionization electron spectroscopy by utilizing a mu ltichannel scaler and 2 MB random access memory. This technique provid es a two-dimensional Penning ionization electron spectrum (2D-PIES) in which the Penning electron intensity is observed as a continuous func tion of both collision energies and electron energies, The observed 2D -PIES for Ar/He (2(3)S and 2(1)S) was compared with calculated 2D-PIE S obtained by classical trajectory calculations based on interaction p otentials and transition probabilities. (C) 1996 American Institute of Physics.