The magnified threshold energy range of the cross section of Sn<sup>6 +</sup>

<p><strong>Figure 4.</strong> The magnified threshold energy range of the cross section of Sn<sup>6 +</sup>. Same notation as in figure <a href="http://iopscience.iop.org/0953-4075/46/17/175201/article#jpb473129f2" target="_blank">2</a>. The vertical arrows indicate the energies of the predicted ground-state ionization threshold (arrow <em>a</em>), of the experimental threshold of the ground-state electron configuration (arrow <em>b</em>) and of an onset for calculated EA contributions (arrow <em>c</em>).</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>