Abstract
We investigated X-ray emission from highly charged slow Pbq+ ions (q = 50-58, E = 8.5 qkeV) hitting metal surfaces. We confirmed occurrence of internal dielectronic excitation (IDE) i.e. excitation of the closed M-shell core by relaxation of "hollow-atom" electrons with a probability of unity. Calculation of singly and doubly excited states showed that population of singly excited states of n > 9 are most likely causing the core excitation. Further, we demonstrate a method for measuring the mean depth where X-ray emission occurs. The emission of the X-rays from ions with initial M vacancies occurs inside the bulk.