Continuum-electron emission from colliding atoms

An overview of the experimental and the theoretical investigations on the production of continuum-electrons from slow heavy-ion-atom collisions at keV impact energies is presented. It is shown that the Auger transitions in quasimolecule formed transiently in heavy-ion-atom collisions, have appreciable cross-sections and turn out to be a rather prevalent phenomenon. It is demonstrated that the simple Airy approximation accounts sufficiently well for the general behaviour of the emission spectra of continuum-electron distribution in energetic atomic collisions. The difference existing between experiment and theory manifests itself in more subtle details in the oscillations of the cross-section at Esub(c) < Esub(c)(Rsub(o)) and in the values of cross-section in the classically forbidden region at high electron energies. The employment of an electron-scattered-ion coincidence technique in studies of continuum-electron spectra provides a quantitative spectroscopy of quasimolecules with regard to the energy and the width of an auto-ionizing level. Selected examples are cited to illustrate the importance of extracting information on the above spectroscopic parameters from emission spectra of continuum-electrons. (author). 33 refs. 7 figures