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arXiv · 2001.07713

Revealing the Two-Electron Cusp in the Ground States of He and H2 via Quasifree Double Photoionization

S. Grundmann·V. Serov·F. Trinter·K. Fehre·N. Strenger·A. Pier·M. Kircher·D. Trabert·M. Weller·J. Rist·L. Kaiser·A. W. Bray·L. Ph. H. Schmidt·J. B. Williams·T. Jahnke·R. Dörner·M. S. Schöffler·A. S. Kheifets
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Abstract

We report on kinematically complete measurements and ab initio non-perturbative calculations of double ionization of He and H2 by a single 800 eV circularly polarized photon. We confirm the quasifree mechanism of photoionization for H2 and show how it originates from the two-electron cusp in the ground state of a two-electron target. Our approach establishes a new method for mapping electrons relative to each other and provides valuable insight into photoionization beyond the electric-dipole approximation.

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S. Grundmann, V. Serov, F. Trinter, K. Fehre, N. Strenger, A. Pier, M. Kircher, D. Trabert, M. Weller, J. Rist, L. Kaiser, A. W. Bray, L. Ph. H. Schmidt, J. B. Williams, T. Jahnke, R. Dörner, M. S. Schöffler, A. S. Kheifets. 2020-01-21. Revealing the Two-Electron Cusp in the Ground States of He and H2 via Quasifree Double Photoionization. https://doi.org/10.1103/physrevresearch.2.033080

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