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

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.