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arXiv · 2310.09155

Partial-wave analysis of $\tau^-\to\pi^-\pi^-\pi^+\nu_\tau$ at Belle

Andrei Rabusov·Daniel Greenwald·Stephan Paul
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Abstract

We present preliminary results of a partial-wave analysis of $\tau^-\to\pi^-\pi^-\pi^+\nu_\tau$ in data from the Belle experiment at the KEKB $\mathrm{e}^+\mathrm{e}^-$ collider. We demonstrate the presence of the $\mathrm{a}_1(1420)$ and $\mathrm{a}_1(1640)$ resonances in tauon decays and measure their masses and widths. We also present validation of our findings using a model-independent approach. Our results can improve modeling in simulation studies necessary for measuring the tauon electric and magnetic dipole moments and Michel parameters.

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Andrei Rabusov, Daniel Greenwald, Stephan Paul. 2023-10-13. Partial-wave analysis of $\tau^-\to\pi^-\pi^-\pi^+\nu_\tau$ at Belle. https://arxiv.org/abs/2310.09155

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