# ICHEP 2022

Jul 6 – 13, 2022
Bologna, Italy
Europe/Rome timezone

## Partial wave analysis of the $\tau\to3\pi\nu_\tau$ decay at Belle

Jul 8, 2022, 7:05 PM
1h 25m
Bologna, Italy

#### Bologna, Italy

Palazzo della Cultura e dei Congressi
Poster Quark and Lepton Flavour Physics

### Speaker

Mr Andrei Rabusov (Technical University of Munich)

### Description

The COMPASS experiment saw a potential new hadron resonance, the
$\text{a}_1(1420)$, that does not fit into the quark model. Its existence
can be independently verified in the semi-leptonic decay of
$\tau^-\to\pi^-\pi^-\pi^+\nu_\tau$. Also, such a study can reveal a clear
picture on the $\text{a}_1(1260)$ axial vector meson parameters, and test
the presence of the pseudoscalar and spin-exotic contributions. Moreover,
the results of the study can be used later in the measurements of the $\tau$
electric and magnetic dipole moments and $\tau$ Michel parameters. We
present the preliminary results of the $\tau^-\to\pi^-\pi^-\pi^+\nu_\tau$
decay with the Belle detector at the KEKB energy-asymmetric
$\text{e}^+\text{e}^-$ collider using partial-wave analysis technique.

In-person participation Yes

### Primary authors

Mr Andrei Rabusov (Technical University of Munich) Dr Daniel Greenwald (Technical University of Munich) Prof. Stephan Paul (TU Munich)