Associative Ionisation in Low Energy Collisions

Measurements are presented and discussed that deal with associative ionisation in the collision of two hydrogen or deuterium atoms, one of which is excited in the 2s, 3s or 4s state. Total cross sections are given for collision energies ranging from 5 meV to 4 eV. Also reported here are some cross section measurements of associative ionisation in the collision of a negative ion (H-, D- or O-) with a positive one (D+, H-2(+), D-2(+) He+, C+ or O+).