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arXiv · 0803.4305

Two-loop QED corrections with closed fermion loops

V. A. Yerokhin·P. Indelicato·V. M. Shabaev
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Abstract

We report a calculation of all two-loop QED corrections with closed fermion loops for the n=1 and n=2 states of H-like ions and for a wide range of the nuclear charge numbers Z=1-100. The calculation is performed to all orders in the binding-strength parameter (Z \alpha), with the exception that in a few cases the free-loop approximation is employed in the treatment of the fermion loops. Detailed comparison is made with previous (Z \alpha)-expansion calculations and the higher-order remainder term to order \alpha^2 (Z \alpha)^6 is identified.

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V. A. Yerokhin, P. Indelicato, V. M. Shabaev. 2008-03-30. Two-loop QED corrections with closed fermion loops. https://doi.org/10.1103/physreva.77.062510

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