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arXiv · 1912.11877

Double-ionization mechanisms of magnesium driven by electron impact

Shivan Mittal·Jonathan Dubois·Cristel Chandre·Ahmet Turgay Uzer
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Abstract

We study double ionization of Mg by electron impact through the vantage point of classical mechanics. We consider all electron-electron correlations in a Coulomb four-body problem, where three electrons belong to the atom and the fourth electron causes the impact ionization. From our model we compute the double-ionization probability of Mg for impact energies from 15, to 125 eV. Double ionization occurs through eight double-ionization mechanisms, which we classify into four categories: inner shell capture, direct, delay and ionized inner shell mechanisms. We show that delay and ionized inner shell mechanisms require electron-electron correlations among the four electrons, and are responsible for the second increase in the double-ionization probability. Furthermore, we show that our theoretical prediction about the relative prominence of certain double ionization mechanisms is in agreement with experimental results on the relative prominence of non-first- over first-order mechanisms.

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Shivan Mittal, Jonathan Dubois, Cristel Chandre, Ahmet Turgay Uzer. 2019-12-26. Double-ionization mechanisms of magnesium driven by electron impact. https://doi.org/10.1103/physreva.101.062707

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