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Two-photon double ionization of helium in the region of photon energies 42-50 eV

I. A. Ivanov·A. S. Kheifets
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Abstract

We report the total integrated cross-section (TICS) of two-photon double ionization of helium in the photon energy range from 42 to 50 eV. Our computational procedure relies on a numerical solution of the time-dependent Schr\"odinger equation on a square-integrable basis and subsequent projection of this solution on a set of final states describing two electrons in continuum. Close to the threshold, we reproduce results previously known from the literature. The region 47-50 eV seems to have been previously unexplored. Our results suggest that TICS, as a function of the photon energy, grows monotonously in the region 42-50 eV. We also present fully resolved triple differential cross sections for selected photon energies.

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I. A. Ivanov, A. S. Kheifets. 2006-12-11. Two-photon double ionization of helium in the region of photon energies 42-50 eV. https://doi.org/10.1103/physreva.75.033411

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