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arXiv · 2112.10686

The $\tau\to\nu_\tau\pi e^+e^-$ decay revisited

Adolfo Guevara
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Abstract

The recent results from Belle of the $\tau^-\to\nu_\tau\pi^-e^+e^-$ analysis has incentivated us to make a reanalysis of a former work where the Structure Dependent parts are obtained using Resonance Chiral Theory. Here we rely on the same theory accounting for effects that explicitly break such symmetry. A motivation is the involved $W\pi\gamma^\star$ vertex, utterly relevant in computing $\tau^- \to \nu_{\tau}\pi^-$ radiative corrections.

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Adolfo Guevara. 2021-12-20. The $\tau\to\nu_\tau\pi e^+e^-$ decay revisited. https://arxiv.org/abs/2112.10686

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