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arXiv · 1607.07059

Hyperfine Splitting in True Muonium to $\mathcal{O}(m_\mu\alpha^6)$: Two Photon Annihilation Contribution from Other Flavors

Yao Ji·Henry Lamm
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Abstract

The two-photon-annihilation contribution to the true muonium hyperfine splitting arising from $e$ and $\tau$ loops is obtained analytically at order $m_\mu\alpha^6$. The contribution to the hyperfine splitting is $-2.031092873 m_\mu\alpha^6/n^3\pi^2=-793.926988/n^3$ MHz. The contribution to the triplet true muonium decay rate has also been obtained and was found to be $9.825708266 m_\mu\alpha^6/n^3\pi^2=3840.737698/n^3$ MHz. Additional results have been computed for other purely leptonic bound states.

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Yao Ji, Henry Lamm. 2016-07-24. Hyperfine Splitting in True Muonium to $\mathcal{O}(m_\mu\alpha^6)$: Two Photon Annihilation Contribution from Other Flavors. https://doi.org/10.1103/physreva.94.032507

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