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arXiv · 1308.2138

Two-loop QED corrections with closed fermion loops for the bound-electron g factor

V. A. Yerokhin·Z. Harman
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Abstract

Two-loop QED corrections with closed fermion loops are calculated for the 1s bound-electron g factor. Calculations are performed to all orders in the nuclear binding strength parameter Zα(where Z is the nuclear charge and αis the fine structure constant) except for the closed fermion loop, which is treated within the free-loop (Uehling) approximation in some cases. Comparison with previous Zα-expansion calculations is made and the higher-order remainder of order α^2(Zα)^5 and higher is separated out from the numerical results.

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V. A. Yerokhin, Z. Harman. 2013-08-09. Two-loop QED corrections with closed fermion loops for the bound-electron g factor. https://doi.org/10.1103/physreva.88.042502

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