Search for a Supersymmetric Partner to the Top Quark in Final States with Jets and Missing Transverse Momentum at s=7 TeV with the ATLAS Detector

A search for direct pair production of supersymmetric top squarks (t₁) is presented, assuming the t₁ decays into a top quark and the lightest supersymmetric particle, χ₁⁰, 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 t₁ versus χ₁⁰ mass plane is evaluated: 370<m_t₁<465 GeV is excluded for m_χ₁⁰~0 GeV while m_t₁=445 GeV is excluded for m_χ₁⁰≤50 GeV.