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Updated: Jul 2, 2026

Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
Intrashell electron-interaction-mediated photoformation of hollow atoms near threshold
S Huotari1, K Hämäläinen, R Diamant
1ESRF, 6 rue Jules Horowitz, B.P. 220, F-38043 Grenoble cedex, France.
Abstract:
Double photoionization (DPI) of an atom by a single photon is a direct consequence of electron-electron interactions within the atom. We have measured the evolution of the K-shell DPI from threshold up in transition metals by high-resolution x-ray emission spectroscopy of the Kh alpha hypersatellites, photoexcited by monochromatized synchrotron radiation. The measured evolution of the single-to-double photoionization cross-section ratio with excitation energy was found to be universal. Theoretical fits suggest that near threshold DPI is predominantly a semiclassical knockout effect, rather than the purely quantum-mechanical shake-off observed at the infinite photon energy limit.
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