Theoretical study of inner-shell alignment of atoms in electron impact ionisation: angular distribution and polarisation of X-rays and Auger electrons

The alignment of ions with an inner-shell vacancy resulting from ionisation by a fast charged particle is considered. The alignment has been calculated in the Born approximation using the Herman-Skillman model. The angular distribution and polarisation of characteristic X-radiation and Auger electrons from decay of aligned ions are discussed. It is shown that the theoretical anisotropy of the angular distribution is sensitive to the wavefunctions used. The results of calculations using the Herman-Skillman wavefunctions are in much better agreement with experiment than the previous calculations involving the hydrogen-like functions.