MOLECULAR-ALIGNMENT DEPENDENCE IN THE TRANSFER EXCITATION OF H-2

Molecular-alignment effects in the transfer excitation of H-2 by high- velocity heavy ions are studied using a two-step mechanism with amplit udes evaluated from first-order perturbation theory. Two-electron tran sfer excitation is treated as a result of two independent collision pr ocesses (excitation and electron transfer). Cross sections for each on e-electron subprocess as well as the combined two-electron process are calculated as functions of the molecular-alignment angle. Within the independent-electron approximation, the dynamic roles of electron exci tation and transfer in conjunction with molecular alignment are explor ed. While both excitation and transfer cross sections may strongly dep end on molecular alignment, it is electron transfer that is largely re sponsible for the molecular-alignment dependence in the transfer excit ation process. Interpretation of some experimental observations based on this model will also be discussed.