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arXiv · 2112.14913

Lattice QCD calculation of the two-photon exchange contribution to the muonic-hydrogen Lamb shift

Yang Fu
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Abstract

We develop a method for lattice QCD calculation of the two-photon exchange (TPE) contribution to the muonic-hydrogen Lamb shift. To demonstrate the feasibility of this method, we also present an exploratory study with a gauge ensemble at $m_π= 142$ MeV. By adopting the infinite-volume reconstruction (IVR) method along with an optimized subtraction scheme, we obtain a preliminary result of the TPE contribution which agrees well with previous calculation using other methods and one magnitude smaller compare to the large $\sim300~μ$eV discrepancy for the proton radius puzzle.

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Yang Fu. 2022-04-14. Lattice QCD calculation of the two-photon exchange contribution to the muonic-hydrogen Lamb shift. https://arxiv.org/abs/2112.14913

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