In order to deduce the experimental beam conditions from the observed x‐ray line emission spectrum of highZelements, atomic radiative data for transition energies and oscillator strengths, ion‐atom impact ionization cross sections, Coster–Kronig yields, and fluorescence yield are needed. In this paper, we report on calculations to study the dependence of these atomic data on ionization stage. It has been found that proton impact ionization cross sections decrease slowly with increasing ionization stage, and the fluoresence yields have discrete jumps when the dominant Auger, Coster–Kronig transitions become energetically forbidden. Our study indicates that thermal ionization effects are not important for the dominantK‐,L‐, andM‐line emissions for plasmas withTe∼ 102eV.