Experimental and theoretical total cross sections for single and double ionization of the open-$4d$-shell ions Xe¹²⁺, Xe¹³⁺, and Xe¹⁴⁺ by electron impact

We present new experimental and theoretical cross sections for electron-impact single ionization of Xe¹²⁺ and Xe¹³⁺ ions, and double ionization of Xe¹²⁺, Xe¹³⁺ and Xe¹⁴⁺ ions for collision energies from the respective ionization thresholds up to 3500 eV. The calculations use the fully relativistic subconfiguration-averaged distorted-wave (SCADW) approach and, partly, the more detailed level-to-level distorted wave (LLDW) method. We find that, unlike in previous work, our theoretical cross sections agree with our experimental ones within the experimental uncertainties, except for the near-threshold double-ionization cross sections. We attribute this remaining discrepancy to the neglect of direct-double ionization in the present theoretical treatment.