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Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
Nonsequential two-photon double ionization of atoms: identifying the mechanism
Morten Førre1, Sølve Selstø, Raymond Nepstad
1Department of Physics and Technology, University of Bergen, N-5007 Bergen, Norway. morten.forre@ift.uib.no
Abstract:
We develop an approximate model for the process of direct (nonsequential) two-photon double ionization of atoms. Employing the model, we calculate (generalized) total cross sections as well as energy-resolved differential cross sections of helium for photon energies ranging from 39 to 54 eV. A comparison with results of ab initio calculations reveals that the agreement is at a quantitative level. We thus demonstrate that this complex ionization process can be described by the simple model, providing insight into the underlying physical mechanism. Finally, we use the model to calculate generalized cross sections for the two-photon double ionization of neon in the nonsequential regime.
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