Searches for violation of lepton flavour and baryon number in tau lepton decays at LHCb

Abstract

Searches for the lepton avour violating decay τ- → μ-μ+μ- and the lepton avour and baryon number violating decays τ- → p̄μ+μ- and τ- → pμ-μ- have been carried out using proton-proton collision data, corresponding to an integrated luminosity of 1.0fb-1, taken by the LHCb experiment at √s = 7 TeV. No evidence has been found for any signal, and limits have been set at 90% condence level on the branching fractions: B(τ- →μ-μ+μ-)< 8.0 × 10-8, B(τ- → p̄μ+μ-)< 3.3 × 10-7 and B(τ- → pμ-μ-)< 4.4 × 10-7.The results for the τ- → pμ+μ- and τ- → p̄ μ-μ- decay modes represent the rst direct experimental limits on these channels. © 2013 CERN. Published by Elsevier B.V.