Physical mechanisms and scaling laws of K-shell double photoionization.
We report on the photon energy dependence of the K-shell double photoionization (DPI) of Mg, Al, and Si. The DPI cross sections were derived from high-resolution measurements of x-ray spectra following the radiative decay of the K-shell double vacancy states. Our data evince the relative importance of the final-state electron-electron interaction to the DPI. By comparing the double-to-single K-shell photoionization cross-section ratios for neutral atoms with convergent close-coupling calculations for He-like ions, the effect of outer shell electrons on the K-shell DPI process is assessed. Universal scaling of the DPI cross sections with the effective nuclear charge for neutral atoms is revealed.
Hoszowska
J
J
Department of Physics, University of Fribourg, CH-1700 Fribourg, Switzerland.
Kheifets
A K
AK
Dousse
J-Cl
JC
Berset
M
M
Bray
I
I
Cao
W
W
Fennane
K
K
Kayser
Y
Y
Kavcic
M
M
Szlachetko
J
J
Szlachetko
M
M