Search for Lepton-Flavor Violation in Z -Boson Decays with τ Leptons with the ATLAS Detector

UNSPECIFIED (2021) Search for Lepton-Flavor Violation in Z -Boson Decays with τ Leptons with the ATLAS Detector. Physical review letters, 127 (27): 271802. ISSN 1079-7114

Abstract

A search for lepton-flavor-violating Z→eτ and Z→μτ decays with pp collision data recorded by the ATLAS detector at the LHC is presented. This analysis uses 139 fb-1 of Run 2 pp collisions at s=13 TeV and is combined with the results of a similar ATLAS search in the final state in which the τ lepton decays hadronically, using the same data set as well as Run 1 data. The addition of leptonically decaying τ leptons significantly improves the sensitivity reach for Z→ℓτ decays. The Z→ℓτ branching fractions are constrained in this analysis to B(Z→eτ)