ELECTRONIC EXCITATION PROCESSES IN THE COLLISIONAL SYSTEM NA(3(2)S)-1)-]NA-ASTERISK+RB+(S-1) BY CROSSED MOLECULAR-BEAMS IN THE 0.1-5.0 KEV ENERGY-RANGE(RB+(S)

Electronic excitation processes in the collisional system Na-Rb+ in th e energy range 0.1-5.0 keV have been studied by means of a crossed mol ecular beam technique and measuring the fluorescent emission of the ex cited species formed, these being Na(3(2)P(1/2.3/2)), Na(7(2)S(1/2)), Na(6(2)D(5/2.3/2)), Na(5(2)D(5/2.3/2)) and Na(4(2)D(5/2.3/2)). For all of them the total excitation cross-section dependence on collision en ergy (c.e.) has been determined. In addition, the first one has been r esolved in its J components, the branching ratio having a value c.e.-i ndependent and close to the statistical one. Also, by polarization ani sotropy measurements the Na(3(2)S(1/2)) --> Na(3(2)P(3/2)) excitation cross section has been resolved into its M(J) components, whose c.e. d ependence shows possible interference effects at low c.e. Results for this first excitation have been interpreted both in terms of a linear Landau-Zener-Stuckelberg model and of the evolution of quasi-diabatic molecular orbitals of the Na-Rb+ quasi-molecule obtained by ab initio calculations.