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arXiv · 1512.00287

Contribution of high-nl shells to electron-impact ionization processes

V. Jonauskas·A. Kynienė·G. Merkelis·G. Gaigalas·R. Kisielius·S. Kučas·Š. Masys·L. Radžiūtė·P. Rynkun
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Abstract

The contribution to electron-impact ionization cross sections from excitations to high-nl shells and a consequent autoionization is investigated. We perform relativistic subconfiguration-average and detailed level-to-level calculations for this process. Ionization cross sections for the W27+ ion are presented to illustrate the large influence of the high shells (n >= 9) and orbitals (l >= 4) in the excitation-autoionization process. The obtained results show that the excitations to the high shells (n >= 9) increase cross sections of the indirect ionization process by a factor of 2 compared to the excitations to the lower shells (n <= 8). The excitations to the shells with orbital quantum number l = 4 give the largest contribution comparedwith the other orbital quantum numbers l. Radiative damping reduces the cross sections of the indirect process approximately twofold in the case of the level-to-level calculations. Determined data show that the excitation-autoionization process contributes approximately 40% to the total ionization cross sections.

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V. Jonauskas, A. Kynienė, G. Merkelis, G. Gaigalas, R. Kisielius, S. Kučas, Š. Masys, L. Radžiūtė, P. Rynkun. 2015-12-01. Contribution of high-nl shells to electron-impact ionization processes. https://doi.org/10.1103/physreva.91.012715

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