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Convergent close-coupling calculations of two-photon double ionization of helium

A. S. Kheifets·I. A. Ivanov
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Abstract

We apply the convergent close-coupling (CCC) formalism to the problem of two-photon double ionization of helium. The electron-photon interaction is treated perturbatively whereas the electron-electron interaction is included in full. The integrated two-photon double ionization cross-section is substantially below non-perturbative literature results. However, the pattern of the angular correlation in the two-electron continuum is remarkably close to the non-perturbative time-dependent close-coupling calculation of Hu {\em et al} [J. Phys. {\bf B38}, L35 (2005)]

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A. S. Kheifets, I. A. Ivanov. 2006-01-19. Convergent close-coupling calculations of two-photon double ionization of helium. https://doi.org/10.1088/0953-4075/39/7/015

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