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arXiv · 0908.3754

The two-loop self-energy for the ground state of medium-Z hydrogen-like ions

V. A. Yerokhin
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Abstract

The two-loop self-energy correction to the ground state Lamb shift is calculated for hydrogen-like ions with the nuclear charge Z=10-30 without any expansion in the binding field of the nucleus. A calculational technique is reported for treatment of Feynman diagrams in the mixed coordinate-momentum representation, which yields significant improvement in numerical accuracy as compared to previous results. An extrapolation of the all-order numerical data towards Z=1 yields a result for the higher-order remainder function for hydrogen. The previously reported disagreement between the all-order and the perturbative approaches is reduced to the marginal agreement.

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V. A. Yerokhin. 2009-08-26. The two-loop self-energy for the ground state of medium-Z hydrogen-like ions. https://doi.org/10.1103/physreva.80.040501

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