One and two electron transitions in multiply charged ions and helium collisions

In this paper, an extension of the already-developed and modified over-barrier model is presented to study theoretically one and two electron transitions between helium atoms and multiply charged ion collisions at a low-to-intermediate velocity (νBohr ∼ 5νBohr). It is found that the present model can partially reproduce the experimentally obtained velocity dependence of the absolute cross-sections which is also supported by the results of the classical trajectory Monte Carlo (CTMC) method.