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arXiv · 1603.03930

Positronium energy levels at order $m \alpha^7$: Product contributions in the two-photon-annihilation channel

Gregory S. Adkins·Lam M. Tran·Ruihan Wang
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Abstract

Ongoing improvements in the measurement of positronium transition intervals motivate the calculation of the $O(m \alpha^7)$ corrections to these intervals. In this work we focus on corrections to the spin-singlet parapositronium energies involving virtual annihilation to two photons in an intermediate state. We have evaluated all contributions to the positronium S-state energy levels that can be written as the product of a one-loop correction on one side of the annihilation event and another one-loop correction on the other side. These effects contribute $\Delta E = -0.561971(25) m \alpha^7/\pi^3$ to the parapositronium ground state energy.

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Gregory S. Adkins, Lam M. Tran, Ruihan Wang. 2016-03-12. Positronium energy levels at order $m \alpha^7$: Product contributions in the two-photon-annihilation channel. https://doi.org/10.1103/physreva.93.052511

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