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arXiv · 2405.09650

Neutral-pion decay into an electron-positron pair: A review and update

Tomáš Husek
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Abstract

This work aims to review several aspects of the current status of the rare $\pi^0\to e^+e^-$ decay. A particular emphasis is made on radiative corrections and detailed interpretation of related quantities, some numbers appearing in the literature are updated, and the connection with the Dalitz decay, $\pi^0\to e^+e^-\gamma$, is discussed. This comes timely as it is aligned with an announcement of a preliminary result of a new branching-ratio measurement done by the NA62 Collaboration, which brings new light into an earlier-reported discrepancy between the Standard Model prediction and the (until-recently latest) precise KTeV result.

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Tomáš Husek. 2024-05-15. Neutral-pion decay into an electron-positron pair: A review and update. https://doi.org/10.1103/physrevd.110.033004

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