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The Single Photon Annihilation Contributions to the Positronium Hyperfine Splitting to Order $m_eα^6$

A. H. Hoang·P. Labelle·S. M. Zebarjad
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Abstract

The single photon annihilation contributions for the positronium ground state hyperfine splitting are calculated analytically to order $m_eα^6$ using NRQED. Based on intuitive physical arguments the same result can also be determined by a trivial calculation using results from existing literature. Our result completes the hyperfine splitting calculation to order $m_eα^6$. We compare the theoretical prediction with the most recent experimental measurement.

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A. H. Hoang, P. Labelle, S. M. Zebarjad. 1997-07-13. The Single Photon Annihilation Contributions to the Positronium Hyperfine Splitting to Order $m_eα^6$. https://doi.org/10.1103/physrevlett.79.3387

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