| Abstract [eng] |
Electron-impact multiple ionization is a process that involves dealing with at least four-body Coulomb problem, making the study of such a process complicated. In this dissertation, a multi-step approach is utilized to study electron-impact double and triple ionization processes for Se2+, Se3+, and B+ ions. The multi-step approach treats electron-impact direct double ionization as a sequence of separate ionization and excitation processes, thereby dividing the complex multiple ionization problem into simpler components. It encompasses two- and three-step processes through which direct double ionization can occur, including ionization-ionization, excitation-ionization-ionization, and ionization-excitation-ionization paths. The energy distribution of the electrons participating in subsequent ionization or excitation processes after the initial interaction is also studied. For indirect double ionization, additional excitation-ionization-autoionization and ionization-excitation-autoionization processes are considered. Electron-impact triple ionization is studied as a sum of the direct double ionization process followed by autoionization and Auger cascades after the ionization of the inner shell of the considered ion. The dissertation demonstrates the significant influence of three-step processes on double and triple ionization. |
