“…The alignment of a vacancy can be investigated experimentally by measuring the angular distribution or polarisation of X-rays or the angular distribution of Auger electrons arising from a decay of the vacancy. During the last two decades numerous experimental investigations of the inner-shell alignment induced by proton or ion collisions with atoms have reported (see reviews [1][2][3]). A comparison of experimental data with theoretical calculations based on the first Born approximation or on the equivalent semiclassical approximation (SCA) with a rectilinear trajectory shows that first order approximations provide a good description of the experi-* Permanent address: Institute of Nuclear Physics, Moscow State University, SU-119899 Moscow, US SR mental data for the relative impact velocities v/v,t >0.3 (v,~ is the classical velocity of an electron of the considered subshell).…”