Lepton-flavour violation in hadronic tau decays and $\ell$-$\tau$ conversion in nuclei

TL;DR

This paper analyzes lepton-flavour-violating processes involving tau leptons within the Standard Model Effective Field Theory, deriving constraints on operator coefficients from current and future experimental data.

Contribution

It provides a model-independent framework for constraining lepton-flavour violation in tau decays and $ au$-$ ext{lepton}$ conversion processes using EFT operators up to dimension 6.

Findings

Established bounds on Wilson coefficients from existing experimental limits.

Framework can incorporate future experimental data from Belle II and other experiments.

Provides a systematic approach for analyzing lepton-flavour violation in tau processes.

Abstract

Within the Standard Model Effective Field Theory framework, with operators up to dimension 6, we perform a model-independent analysis of the lepton-flavour-violating processes involving tau leptons. Namely, we study hadronic tau decays and $\ell$-$\tau$ conversion in nuclei ($\ell=e,\mu$). Based on available experimental limits, we establish constraints on the Wilson coefficients of the operators contributing to these processes. The related information from Belle II and foreseen future experiments can be easily incorporated into the resulting framework.