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

Searches for the lepton flavour violating decay τ−→μ−μ+μ−τ−→μ−μ+μ− and the lepton flavour and baryon number violating decays sourceτ−→p¯μ+μ− and τ−→pμ−μ−τ−→pμ−μ− have been carried out using proton–proton collision data, corresponding to an integrated luminosity of 1.0 fb−11.0 fb−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%90% confidence level on the branching fractions: B(τ−→μ−μ+μ−)<8.0×10−8B(τ−→μ−μ+μ−)<8.0×10−8, B(τ−→p¯μ+μ−)<3.3×10−7 and B(τ−→pμ−μ−)<4.4×10−7B(τ−→pμ−μ−)<4.4×10−7. The results for the τ−→p¯μ+μ− and τ−→pμ−μ−τ−→pμ−μ− decay modes represent the first direct experimental limits on these channels

Measurement of the time-dependent CP asymmetry in B0 -> J/ψ KS0 decays

This Letter reports a measurement of the CP violation observables SJ/ψK0S and CJ/ψK0S in the decay channel B0→J/ψK0S performed with 1.0 fb−1 of pp collisions at s√=7 TeV collected by the LHCb experiment. The fit to the data yields SJ/ψK0S=0.73±0.07(stat)±0.04(syst) and CJ/ψK0S=0.03±0.09(stat)±0.01(syst). Both values are consistent with the current world averages and within expectations from the Standard Model