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arXiv · 2008.07550

Logarithmically enhanced Euler-Heisenberg Lagrangian contribution to the electron gyromagnetic factor

Andrzej Czarnecki·Jan Piclum·Robert Szafron
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Abstract

Contrary to what was previously believed, two-loop radiative corrections to the $g$-factor of an electron bound in a hydrogen-like ion at $\mathcal{O}\left(α^2 (Zα)^5\right)$ exhibit logarithmic enhancement. This previously unknown contribution is due to a long-distance light-by-light scattering amplitude. Taking an effective field theory approach, and using the Euler-Heisenberg Lagrangian, we find $Δg = -\left( \fracαπ \right)^2\left(Zα\right)^5 \frac{56 π}{135}\ln Zα$.

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Andrzej Czarnecki, Jan Piclum, Robert Szafron. 2020-08-17. Logarithmically enhanced Euler-Heisenberg Lagrangian contribution to the electron gyromagnetic factor. https://doi.org/10.1103/physreva.102.050801

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