Projectile energy dependence of L x-ray emission from fast, highly charged Xe ions traveling in solids

L x-ray emission from Xe ions incident on a variety of solid targets at energies ranging from 6 to 15 MeV/u has been investigated using a curved crystal spectrometer of moderate resolution. Analysis of the spectra provided estimates of the average charges and (in some cases) the charge distributions of those ions emitting L x rays inside the targets. Calculations employing theoretical electron capture and loss cross sections were used to examine the dependence on depth within the target of contributions to the spectra from Xe ions having different average numbers of L and M electrons. Average charges and charge distributions deduced from the x-ray spectra were found to agree quite well with those predicted by the model calculations.