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arXiv · 2201.12764

Triple-product asymmetry in the radiative two-pion tau decay

Cheng Chen·Chun-Gui Duan·Zhi-Hui Guo
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Abstract

In this work, we perform a detailed study of the $τ^-\toπ^-π^0γν$ decay process within the resonance chiral theory. We pay special attention to the triple-product asymmetry in the $τ^-\toπ^-π^0γν$ process. The minimal resonance chiral Lagrangian and the odd-intrinsic parity resonance operators are simultaneously included to calculate the decay amplitudes. Various invariant-mass distributions in the $π^-π^0$, $π^-γ$ and $π^0γ$ systems are studied and they reveal different resonance dynamics. We further predict the intriguing nonzero triple-product asymmetry distributions, which may provide useful guidelines for future experimental measurements conducted at the Belle-II and super tau-charm facilities.

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Cheng Chen, Chun-Gui Duan, Zhi-Hui Guo. 2022-11-05. Triple-product asymmetry in the radiative two-pion tau decay. https://doi.org/10.1007/jhep08(2022)144

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