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arXiv · 1001.5436

The two-loop self-energy: diagrams in the coordinate-momentum representation

Vladimir A. Yerokhin
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Abstract

The paper reports a technique of evaluation of Feynman diagrams in the mixed coordinate-momentum representation. The technique is employed for a recalculation of the two-loop self-energy correction for the ground state of hydrogen-like ions with the nuclear charge numbers Z=10-30. The numerical accuracy is considerably improved as compared to the previous calculations. The higher-order (in Zα) remainder function is inferred from the numerical results and extrapolated towards Z=0 and 1. The extrapolated value for hydrogen is consistent (but still not in perfect agreement) with the analytical result obtained within the perturbative approach.

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Vladimir A. Yerokhin. 2010-01-29. The two-loop self-energy: diagrams in the coordinate-momentum representation. https://doi.org/10.1140/epjd%2Fe2010-00089-4

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