K-shell ionization cross sections in nearly symmetric collisions by S and Cl impact

K-shell ionization cross sections in collisions of S and Cl ions with target atoms with atomic numberZ2=11–22 have been measured in the energy range from 3.9 to 48 MeV. The data are interpreted in terms of the statistical model of electron diffusion to the continuum. The distribution ofK-vacancies between the projectile and the target atoms are discussed in the framework of the vacancy sharing process.