Associative ionization in collisions between two excited reactants

Absolute and relative cross sections were obtained for the associative ionization (AI) reaction He^*+Ne^*-->HeNe⁺+e by a merging-beams technique over a range of interaction energy W from 0.01 to 10 eV. The He* represents a composite of He(2¹S) and He(2³S), and the Ne* a composite of Ne(3s³P₂) and Ne(3s³P₀). This study represents the first direct evidence of AI for which both reactants are excited. Studies were also made of the possible AI reaction Ne^*+Ar^*-->NeAr⁺+e from thermal energy to 10 eV.