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arXiv · hep-ph/0111084

Two-Loop Self-Energy Corrections to the Fine-Structure

Ulrich D. Jentschura·Krzysztof Pachucki
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Abstract

We investigate two-loop higher-order binding corrections to the fine structure, which contribute to the spin-dependent part of the Lamb shift. Our calculation focuses on the so-called ``two-loop self-energy'' involving two virtual closed photon loops. For bound states, this correction has proven to be notoriously difficult to evaluate. The calculation of the binding corrections to the bound-state two-loop self-energy is simplified by a separate treatment of hard and soft virtual photons. The two photon-energy scales are matched at the end of the calculation. We explain the significance of the mathematical methods employed in the calculation in a more general context, and present results for the fine-structure difference of the two-loop self-energy through the order of $α^8$.

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Ulrich D. Jentschura, Krzysztof Pachucki. 2002-02-01. Two-Loop Self-Energy Corrections to the Fine-Structure. https://doi.org/10.1088/0305-4470%2F35%2F8%2F310

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