The $\tau \to {\nu }_{\tau }\pi e^{+}{e}^{-}$ decay revisited

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.

Comments: Proceedings to the 19th International Conference on Hadron Spectroscopy and Structure 2021, 5 pages, 6 Figures