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arXiv · 2405.19264

Measurement of the presence of $\mathrm{a}_1(1420)$ and $\omega(782)$ in $\tau^-\to\pi^-\pi^-\pi^+\nu_\tau$ at Belle

Andrei Rabusov·Daniel Greenwald·Stephan Paul
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Abstract

We present preliminary results of a partial-wave analysis of $\tau^-\to\pi^-\pi^-\pi^+\nu_\tau$ using data from the Belle experiment at the KEKB $\mathrm{e}^+\mathrm{e}^-$ collider. We validate our model with a model-independent analysis. We see the $\mathrm{a}_1(1420)$ and a G-parity-violating $1^-[\omega(782)\pi]_\mathrm{P}$ wave in tauon decays. Our results will improve models used in simulation studies necessary for measuring the electric and magnetic dipole moments and Michel parameters of the $\tau$.

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Andrei Rabusov, Daniel Greenwald, Stephan Paul. 2024-05-29. Measurement of the presence of $\mathrm{a}_1(1420)$ and $\omega(782)$ in $\tau^-\to\pi^-\pi^-\pi^+\nu_\tau$ at Belle. https://doi.org/10.21468/scipostphysproc.17.008

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