Hadronic \tau decays and QCD

TL;DR

This paper reviews how hadronic tau decays serve as a valuable tool for studying QCD, providing insights into hadron dynamics, the strong coupling constant, and the strange quark mass through spectral function analysis.

Contribution

It summarizes recent experimental results on exclusive decay channels and discusses their implications for QCD parameters and nonperturbative effects.

Findings

Accurate determination of the strong coupling constant from spectral functions.

Extraction of the strange quark mass from strange decay channels.

Validation of QCD predictions through spectral function analyses.

Abstract

Hadronic decays of the $\tau$ lepton provide a clean source to study hadron dynamics in an energy regime dominated by resonances, with the interesting information captured in the spectral functions. Recent results on exclusive channels are reviewed. Inclusive spectral functions are the basis for QCD analyses, delivering an accurate determination of the strong coupling constant and quantitative information on nonperturbative contributions. Strange decays yield a determination of the strange quark mass.