Search for a supersymmetric partner to the top quark in final states with jets and missing transverse momentum at sqrt(s) = 7 TeV with the ATLAS detector

A search for direct pair production of supersymmetric top squarks (t˜1) is presented, assuming the t˜1 decays into a top quark and the lightest supersymmetric particle, χ˜10, and that both top quarks decay to purely hadronic final states. A total of 16 (4) events are observed compared to a predicted standard model background of 13.5-3.6+3.7(4.4-1.3+1.7) events in two signal regions based on ∫Ldt=4.7  fb-1 of pp collision data taken at √s=7  TeV with the ATLAS detector at the LHC. An exclusion region in the t˜1 versus χ˜10 mass plane is evaluated: 370<mt˜1<465  GeV is excluded for mχ˜10∼0  GeV while mt˜1=445  GeV is excluded for mχ˜10≤50  GeV.