Scattering of \(Yb\) and \(Yb^+\)

Abstract

We calculate the cross sections for scattering of a neutral ytterbium atom with its positive ion at energies up to 30 eV. We identify peaks in the forward direction as arising from elastic collisions and those in the backward direction as from charge transfer. We show that the total cross section follows a semiclassical expression over a large range of energies and that the resonant charge transfer may be characterized by four energy regimes: an s-wave regime at ultralow energies, a modified Langevin regime at low energy, a Langevin regime at medium energy, and an “exchange” regime at high energy. We find large variations between the different isotopes for the two lowest-energy regimes and very little variation for the two highest-energy regimes. Our results are consistent with recent measurements.