Charge capture and impact excitation processes in H+ on He+ collisions: a case study by the time-dependent Schrödinger equation method

We have studied the charge capture and impact excitation processes in H+ on He+ collisions over a wide range of collision energies by solving the time-dependent Schrödinger equation with the classical trajectory approximation for the projectile. The time-dependent Schrödinger equation is solved by the split-operator method with a generalized pseudospectral (nonuniform grid) method in the energy representation. The calculated charge capture cross sections are in good agreement with the available experimental measurements. Our calculated charge capture and impact excitation cross sections are also in reasonable agreement with various close-coupling calculations. Combined with time-dependent density functional theory, our Schrödinger equation method (time propagation) holds significant promise for studying many-electron processes in atom– ion collisions.