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Evaluation of Two-Photon Exchange Graphs for Excited States of Highly Charged Heliumlike Ions
Published
Author(s)
Peter J. Mohr, J Sapirstein
Abstract
Energy shifts arising from two photo exchange graphs are calculated for N=2 triplet states of heliumlike ions and tabulated for the range of nuclear charges Z = 30-92. The results are compared with second-order many-body perturbation theory (MBPT), and the differences identified as QED effects associated with retardation and negative energy states not included in MBPT.
Citation
Physical Review A (Atomic, Molecular and Optical Physics)
Volume
62
Issue
No. 5
Pub Type
Journals
Keywords
helium-like atom, QED, two photon correction
Citation
Mohr, P.
and Sapirstein, J.
(2000),
Evaluation of Two-Photon Exchange Graphs for Excited States of Highly Charged Heliumlike Ions, Physical Review A (Atomic, Molecular and Optical Physics)
(Accessed October 9, 2025)