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Quasiclassical double photoionization from the 2^{1,3}S excited states of helium including shakeoff

A. Emmanouilidou·T. Schneider·J. -M. Rost
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Abstract

We account for the different symmetries of the 2^{1,3}S helium excited states in a quasiclassical description of the knockout mechanism augmented by a quantum shakeoff contribution. We are thus able to formulate the separate contribution of the knockout and shakeoff mechanisms for double photoionization for any excess energy from the 2^{1,3}S states. Photoionization ratios and singly differential cross sections calculated for the 2^{1,3}S excited states of helium are found to be in very good agreement with recent theoretical results.

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A. Emmanouilidou, T. Schneider, J. -M. Rost. 2003-03-13. Quasiclassical double photoionization from the 2^{1,3}S excited states of helium including shakeoff. https://doi.org/10.1088/0953-4075/36/13/303

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