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.
A search for the production of single top-quarks via flavour-changing neutral-currents is presented. Data collected with the ATLAS detector at a centre-of-mass energy of s=7 TeV, corresponding to an integrated luminosity of 2.05 fb−1, are used. Candidate events with a semileptonic top-quark decay signature are classified as signal- or background-like events by using several kinematic variables as...
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