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arXiv · hep-ph/9706523

Some O(α^2) Annihilation Type Contributions to the Orthopositronium Width

V. Antonelli·V. Ivanchenko·E. Kuraev·V. Laliena
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Abstract

We consider some radiative corrections to the lowest order annihilation diagram for the orthopositronium decay rate. The insertion of the renormalized vertex correction in the annihilation graph gives $1.6283 (α/π)^2 Γ_0$. We compute also the contribution of the square of the lowest order annihilation amplitude, which turns out to be $0.1702 (α/π)^2 Γ_0$. Finally, we obtain a term $α^2 \lnαΓ_0$ arising from the correction to the light-light scattering block due to the exchange of one coulombic photon, in agreement with earlier computations.

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V. Antonelli, V. Ivanchenko, E. Kuraev, V. Laliena. 1997-07-17. Some O(α^2) Annihilation Type Contributions to the Orthopositronium Width. https://doi.org/10.1007/s100520050298

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