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arXiv · 1705.09166

One More Hard Three-Loop Correction to Parapositronium Energy Levels

Michael I. Eides·Valery A. Shelyuto
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Abstract

A hard three-loop correction to parapositronium energy levels of order $m\alpha^7$ is calculated. This nonlogarithmic contribution is due to the insertions of one-loop photon propagator in the fermion lines in the diagrams with virtual two-photon annihilation. We obtained $\Delta E=0.03297(2)(m\alpha^7/\pi^3)$ for this energy shift.

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Michael I. Eides, Valery A. Shelyuto. 2017-05-25. One More Hard Three-Loop Correction to Parapositronium Energy Levels. https://doi.org/10.1103/physrevd.96.011301

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