Experimental Study of the Effect of Velocity and Outer-Shell Configuration on the Probability for ProducingKVacancies in Violent Ion-Atom Collisions at keV Energies

The probability for producing $K$ vacancies in violent ion-atom collisions has been found to depend not only on the impact parameter, but also on the impact velocity and the number of vacancies in the atomic $2p$ subshells of the particles prior to the collision. This indicates that the $K$-electron promotion mechanism is different from the $L_{2,3}$-promotion mechanism determined for $Z_1-\mathrm{Ar}$ collisions. The $K$ vacancies are almost exclusively produced in the lower-$Z$ collision partner.