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arXiv · 1501.03900

Role of two-electron processes in the excitation-ionization of lithium atoms by fast ion impact

T. Kirchner·N. Khazai·L. Gulyás
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Abstract

We study excitation and ionization in the 1.5 MeV/amu O$^{8+}$-Li collision system, which was the subject of a recent reaction-microscope-type experiment [Fischer \textit{et al.}, Phys. Rev. Lett. \textbf{109}, 113202 (2012)]. Starting from an independent-electron model based on determinantal wave functions and using single-electron basis generator method and continuum distorted-wave with eikonal initial-state calculations we show that pure single ionization of a lithium $K$-shell electron is too weak a process to explain the measured single differential cross section. Rather, our analysis suggests that two-electron excitation-ionization processes occur and have to be taken into account when comparing with the data. Good agreement is obtained only if we replace the independent-electron calculation by an independent-event model for one of the excitation-ionization processes and also take a shake-off process into account.

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T. Kirchner, N. Khazai, L. Gulyás. 2015-01-16. Role of two-electron processes in the excitation-ionization of lithium atoms by fast ion impact. https://doi.org/10.1103/physreva.89.062702

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