HYPERSPHERICAL APPROACH TO DOUBLE-ELECTRON EXCITATION OF HE BY FAST-ION IMPACT .4. EXCITATION TO THE (2L, 3L') AND (3L, 3L') MANIFOLDS BY MULTIPLY-CHARGED-ION IMPACT

Double-electron excitation processes to (2l,3l') and (3l,3l') manifold s of He atoms by multiply-charged-ion impact have been theoretically i nvestigated using a close-coupling method at the 1.5-MeV/u incident en ergy. Hyperspherical wave functions are adopted to take full account o f strongly correlated motion of two atomic electrons in He. For the ex citation processes to the (2l, 3l') manifold, the cross sections to th e 1D(e) states show the most rapid increase as projectile charge Z(p) increases, while that to the 1P(o) states indicate the slowest. For th e 3l3l' excitation processes, the cross sections to the 1D(e) and 1P(o ) states increase at almost the same rate. It is found that the isomor phism of the charge-density plots of the channel wave functions betwee n the initial and final states governs collision dynamics in direct do uble-electron excitation processes when incident multiply charged ions strongly interact with the target He atoms.