Target thickness dependence of CuKx-ray production for ions moving in thin solid Cu targets

Abstract

Measurements of the target thickness dependence of the target x-ray production yield for incident heavy ions at 1.71 MeV/amu are reported for thin solid Cu targets. The incident ions were F, Al, Si, and S. The charge states of the incident ions were varied in each case to study the target x-ray production for projectiles which have initial charge states $q$ of $q={Z}_{1}$, $q={Z}_{1}\ensuremath{-}1$, and $q<{Z}_{1}\ensuremath{-}1$. The target thicknesses were varied from 3 to 85 \ensuremath{\mu}g/${\mathrm{cm}}^{2}$. In each case the Cu $K$ x-ray yields exhibit a complex exponential dependence on target thickness. A three-component model which includes contributions to the target x-ray production due to ions with zero, one, and two $K$ vacancies is developed to describe the observed target $K$ x-ray yields. The three-component model is fitted to the individual data for each projectile, and the cross sections for both the target and projectile are determined. The fits to the target x-ray data give a systematic representation of the processes involved in x-ray production for heavy ions incident on solid targets.