THEORETICAL PICTURE OF THE DYNAMICS OF THE AUTOIONIZATION EVENT IN HE(2(3)S)-H-2 PENNING IONIZATION - COLLISION ENERGY-DEPENDENCE

A theoretical picture of the dynamics of the autoionization event He(2 (3)S)-H-2(upsilon '' - 0) --> [He...H-2(+)(upsilon')] + e(-) is obtain ed for the values of collision energies ranging from 20 to 150 meV. Th e treatment of the dynamics consists in 2D classical trajectory calcul ations based on static characteristics which include a quantum mechani cal treatment of the perturbed H-2(upsilon '' = 0) and H-2(+)(upsilon' ) vibrational motion. The vibrational populations are dynamical averag es over the local widths of the He(2(3)S)-H-2(upsilon '' = 0) state wi th respect to autoionization to H-2(+)(...He) in its upsilon'th vibrat ional level, the Penning electron energies are related to the local di fferences between the energies of the corresponding perturbed H-2(upsi lon '' - 0)(...He) and H-2(+)(upsilon')(...He) vibrational states. In accordance with recent experimental data, the average Penning electro n energies are found to increase smoothly with increasing collision en ergy. The dependence on collision energy of the vibrational population factors for the nascent Penning ions H-2(+)(upsilon')(...He) is found to be less significant than that obtained from experimental data. Var ious aspects of this difference are discussed.