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Leading logarithmic contribution to the second-order Lamb shift induced by the loop-after-loop diagram

Vladimir A. Yerokhin
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Abstract

Contribution of order α^2 (Z α)^6 \ln^3(Z α)^{-2} to the ground-state Lamb shift in hydrogen induced by the loop-after-loop diagram is evaluated analytically. An additional contribution of this order is found compared to the previous calculation by Karshenboim [JETP 76, 541 (1993)]. As a result, an agreement is achieved for this correction between different numerical and analytical methods.

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Vladimir A. Yerokhin. 2000-10-13. Leading logarithmic contribution to the second-order Lamb shift induced by the loop-after-loop diagram. https://doi.org/10.1103/physrevlett.86.1990

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