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arXiv · 2607.16026

One-loop self-energy using a numerical Green function

Hugo D. Nogueira·Maen Salman·Jean-Philippe Karr
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Abstract

We calculate the one-loop self-energy in hydrogenlike atoms using a numerical Green function obtained by solving the radial Dirac equation in an exponential basis set. The self-energy correction in the ground state of hydrogenlike uranium is obtained with about $10^{-5}$ relative uncertainty in the Feynman gauge. Using a convergence acceleration scheme, we extend our calculations to the region of low nuclear charges. Our results allow calculating the self-energy correction for the hydrogen atom with $10^{-4}$ relative uncertainty. Calculations in the Coulomb gauge are also presented, improving the precision to $10^{-5}$. Present limitations and possible improvements of our method are discussed.

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Hugo D. Nogueira, Maen Salman, Jean-Philippe Karr. 2026-07-17. One-loop self-energy using a numerical Green function. https://arxiv.org/abs/2607.16026

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