K-vacancy production in heavy-ion collisions. IV.K−Llevel matching

As shown in papers I and II of this series, far from symmetry the $K$-vacancy production cross section of the lower-$Z$ ($Z_L$) partner in heavy-ion collisions varies rapidly with the atomic number $Z_H$ of the higher-$Z$ partner. We examine our and other data for $K$ and $L$ x-ray production with 45-94-MeV Ni, 45-110-MeV Br, 47- and 62-MeV I projectiles and interpret the $Z_L$ $K$-vacancy production far from symmetry in terms of the $K-L$ level matching mechanism of Barat and Lichten. Sharing of $3d\sigma$ vacancies on the outgoing part of the collision provides a semiquantitative understanding of the dependence of $K$ and $L$ cross sections on $Z_L$, $Z_H$, and bombarding energy. Some remarks about the general role of vacancy sharing in inner-shell vacancy formation in heavy-ion collisions are made.