CP violation in hadronic tau decays

TL;DR

This paper investigates potential CP violation effects in specific tau lepton decays, exploring how new physics like a charged Higgs could induce measurable asymmetries in decay rates and angular distributions.

Contribution

It introduces new CP-violating asymmetries in tau decays involving a charged Higgs, expanding the search for physics beyond the Standard Model.

Findings

Sizeable CP asymmetries possible in tau -> a_1 pi nu_tau

Triple-product asymmetries in tau -> omega pi nu_tau

Modified rate asymmetries for tau -> K pi pi nu_tau

Abstract

We examine CP violation in the Delta S=0 decays tau -> omega pi nu_tau and tau -> a_1 pi nu_tau and the Delta S=1 decay tau -> K pi pi nu_tau. We assume that the new physics is a charged Higgs. We show that sizeable CP-violating effects are possible in tau -> a_1 pi nu_tau (polarization-dependent rate asymmetry) and tau -> omega pi nu_ tau (triple-product asymmetry). The Delta S=1 decay tau -> K pi pi nu_tau can proceed via several resonances. We construct two modified rate asymmetries and a triple product asymmetry for this decay and discuss the potential sensitivities of these asymmetries.