Origin of structures in the low-energy single-electron continuum in calculations for ion collisions from argon - art. no. 022702

Doubly differential cross sections for inclusive single-electron emission i n 3.6 MeV/amu AU(53+) + Ar collisions are calculated in the continuum disto rted wave with eikonal initial-state approximation. Previously observed str uctures in the low-energy continuum are traced back to a known deficiency o f the Hartree-Fock-Slater target potential that has been used in the work [ R. Moshammer et al., Phys. Rev. Lett. 83, 4721 (1999)]. The structures do n ot occur, if the argon atom is described in terms of the optimized potentia l method, in which the electronic exchange interaction is treated exactly.