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arXiv · 1112.5932

One-photon double ionization of helium: a heuristic formula for the cross section

Morten Førre
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Abstract

Without a formal derivation, we propose a formula for the total and single-differential cross in the problem of one-photon double ionization of an atom. The formula is benchmarked against accurate experimental data for the total cross section of helium. Furthermore, a direct comparison with ab initio calculations for the double ionization of Li+ suggests that the framework is valid for the entire helium isoelectronic sequence. To this end, we introduce a formula for the double ionization of lithium, as well as for the triple ionization of lithium and beryllium.

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Morten Førre. 2011-12-27. One-photon double ionization of helium: a heuristic formula for the cross section. https://doi.org/10.1103/physreva.85.013420

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