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

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 نشر من قبل Sven Grundmann
 تاريخ النشر 2020
  مجال البحث فيزياء
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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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