Hadronic Tau Decays at Belle

TL;DR

This paper reports detailed measurements of hadronic tau decays into three-hadron final states with kaons, including branching ratios and resonance parameters, using a large dataset from the Belle experiment.

Contribution

It provides the first measurements of the K*(892)^0 resonance parameters using tau decay data and offers precise branching ratios for various tau decay modes involving kaons.

Findings

Measured branching ratios for tau decays into kaon-rich final states.

First determination of K*(892)^0 resonance mass and width from tau decays.

Provided detailed resonance and decay mode analysis with high precision.

Abstract

We present a study of hadronic tau decays, especially decay into three-hadron final states with kaon(s), using more than 500fb^-1 of data collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. We measure the branching ratios both inclusively and exclusively while considering the intermediated states of K(892)^*0. The following results are obtained: B(tau- -> K- pi+ pi- nu)=(3.25 +- 0.02 +0.16-0.15)x10^-3, B(tau- -> K- K+ pi- nu)=(1.53 +- 0.01 +- 0.06)x10^-3, B(tau- -> K- K+ K- nu)=(2.60 +- 0.23 +- 0.10)x10^-5 and B(tau- -> K^*(892)^0 K-nu)=(1.56 +- 0.02 +- 0.09)x10^-3. We also measure the mass and width of the K^*(892)^0 resonance as M_{K^*(892)^0} = 895.10 +- 0.27 +- 0.31 MeV/c^2 and Gamma_{K^*(892)^0} = 47.23 +- 0.49 +- 0.79 MeV, which are the first results obtained using tau decay.