Negative-ion detachment cross sections. Progress report

Selected examples of experimental studies which focus on the various aspects of the collisional detachment of negative ions by atoms and molecules are presented in some detail for energies ranging from below the threshold for detachment up to several hundred eV. A qualitative discussion of these experimental observations for low collision energies is based primarily upon features of the intermolecular potentials for the negative ion-atom reactants. Additionally, for the more simple reactants there are several theoretical approaches which have been used with some success to describe the dynamics of the discrete-continuum interaction associated with direct detachment. It has been shown that direct detachment almost always dominates the inelastic scattering in collisions of negative ions with atoms or molecules. For cases where molecular targets are involved, experimental studies are far from extensive and theoretical descriptions of the scattering for such systems are essentially nonNa and Np leached from glass. They also vary for each element while glass shows nearly the same leach rate for both Na and Np