COUPLED-STATE CALCULATIONS IN A MOLECULAR-BASIS - 2S VACANCY PRODUCTION IN SLOW NE+ + NE COLLISIONS

The coupled-state impact-parameter method is employed in a theoretical study of 2s vacancy production in slow Ne++Ne encounters. The time-dependent wavefunction of the collision system is represented in a basis set of molecular orbitals generated from the effective Hamiltonian of the variable-screening model. Differential excitation probabilities and total cross sections for 'inclusive' production of 2s vacancies (i.e., production of 2s vacancies without further specification of the final state of excitation of the collision partners) are calculated within a model in which 2p-2s vacancy transfer is effected either by 1 pi u-2 sigma u rotational coupling or by 3 sigma g-2 sigma g radial coupling. The qualitative features of the differential excitation probabilities are discussed in terms of closed-form solutions of simplified two-state models.