Search for the decay Bs0→μ+μ− with the ATLAS detector

A blind analysis searching for the decay Bs0→μ+μ− has been performed using proton-proton collisions at a centre-of-mass energy of 7 TeV recorded with the ATLAS detector at the LHC. With an integrated luminosity of 2.4 fb−1 no excess of events over the background expectation is found and an upper limit is set on the branching fraction BR(Bs0→μ+μ−)<2.2(1.9)×10−8 at 95% (90%) confidence level.