Overview over the present single-ionization cross sections of Sn<sup>4 +</sup> through Sn<sup>13 +</sup> ions

<p><strong>Figure 1.</strong> Overview over the present single-ionization cross sections of Sn<sup>4 +</sup> through Sn<sup>13 +</sup> ions. The cross-section scale is in units of 10<sup>−17</sup> cm<sup>2</sup> and the cross section for each next ion stage is shifted downwards by 1 <b>×</b> 10<sup>−17</sup> cm<sup>2</sup> and multiplied by a certain coefficient provided on the graph. The thin kinked polygon connects the ground-state ionization thresholds marked by short vertical bars.</p> <p><strong>Abstract</strong></p> <p>Electron-impact single-ionization cross sections of Sn<sup><em>q</em> +</sup> ions in charge states <em>q</em> = 4–13 with 4d<sup>[10 − (<em>q</em> − 4)]</sup> outer-shell configurations have been studied in the energy range from the corresponding thresholds up to 1000 eV. Absolute cross sections and fine-step energy-scan data have been measured employing the crossed-beams technique. Contributions of different ionization mechanisms have been analysed by comparing the experimental data with calculations employing the configuration-averaged distorted wave approximation. Ionization plasma rate coefficients inferred from the experimental data are also presented.</p>