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arXiv · 1502.05529

Wave-packet propagation based calculation of above-threshold ionization in the x-ray regime

Matthew Tilley·Antonia Karamatskou·Robin Santra
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Abstract

We investigate the multi-photon process of above-threshold ionization for the light elements hydrogen, carbon, nitrogen and oxygen in the hard x-ray regime. Numerical challenges are discussed and by comparing Hartree-Fock-Slater calculations to configuration-interaction-singles results we justify the mean-field potential approach in this regime. We present a theoretical prediction of two-photon above-threshold-ionization cross sections for the mentioned elements. Moreover, we study how the importance of above-threshold ionization varies with intensity. We find that for carbon, at x-ray intensities around $10^{23}{\rm Wcm}^{-2}$, two-photon above-threshold ionization of the K-shell electrons is as probable as one-photon ionization of the L-shell electrons.

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Matthew Tilley, Antonia Karamatskou, Robin Santra. 2015-02-19. Wave-packet propagation based calculation of above-threshold ionization in the x-ray regime. https://doi.org/10.1088/0953-4075/48/12/124001

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