The results of a search for pair production of the lighter scalar partners of top quarks ((t) over bar (1)) in 2.05 fb(-1) of pp collisions at root s = 7 TeV using the ATLAS experiment at the LHC are reported. Scalar top quarks are searched for in events with two same flavour opposite-sign leptons (e, mu) with invariant mass consistent with the Z boson mass, large missing transverse momentum and jets in the final state. At least one of the jets is identified as originating from a b-quark. No excess over Standard Model expectations is found. The results are interpreted in the framework of R-parity conserving, gauge mediated Supersymmetry breaking 'natural' scenarios, where the neutralino ((chi) over bar (0)(1)) is the next-to-lightest supersymmetric particle. Scalar top quark masses up to 310 GeV are excluded for 115 GeV m(<(chi) over bar1)(0) 230 GeV at 95% confidence level, reaching an exclusion of m(<(t) over bar1) 330 GeV for m(<(chi) over bar1)(0) = 190 GeV. Scalar top quark masses below 240 GeV are excluded for all values of m((chi) over bar1)(0) > m(z). (c) 2012 CERN. Published by Elsevier B.V. All rights reserved. RI Wemans, Andre/A-6738-2012; de Groot, Nicolo/A-2675-2009; valente, paolo/A-6640-2010; Takai, Helio/C-3301-2012; Delmastro, Marco/I-5599-2012; Livan, Michele/D-7531-2012

The results of a search for pair production of the lighter scalar partners of top quarks ((t) over bar (1)) in 2.05 fb(-1) of pp collisions at root s = 7 TeV using the ATLAS experiment at the LHC are reported. Scalar top quarks are searched for in events with two same flavour opposite-sign leptons (e, mu) with invariant mass consistent with the Z boson mass, large missing transverse momentum and jets in the final state. At least one of the jets is identified as originating from a b-quark. No excess over Standard Model expectations is found. The results are interpreted in the framework of R-parity conserving, gauge mediated Supersymmetry breaking 'natural' scenarios, where the neutralino ((chi) over bar (0)(1)) is the next-to-lightest supersymmetric particle. Scalar top quark masses up to 310 GeV are excluded for 115 GeV m(<(chi) over bar1)(0) 230 GeV at 95% confidence level, reaching an exclusion of m(<(t) over bar1) 330 GeV for m(<(chi) over bar1)(0) = 190 GeV. Scalar top quark masses below 240 GeV are excluded for all values of m((chi) over bar1)(0) > m(z). (c) 2012 CERN. Published by Elsevier B.V. All rights reserved. RI Wemans, Andre/A-6738-2012; de Groot, Nicolo/A-2675-2009; valente, paolo/A-6640-2010; Takai, Helio/C-3301-2012; Delmastro, Marco/I-5599-2012; Livan, Michele/D-7531-2012

Search for scalar top quark pair production in natural gauge mediated supersymmetry models with the ATLAS detector in pp collisions at root s=7 TeV

CAPUA, Marcella;Crosetti G.;Fazio S.;LA ROTONDA, Laura;MASTROBERARDINO, Anna;Meoni E.;SCHIOPPA, Marco;TASSI, Enrico;
2012-01-01

Abstract

The results of a search for pair production of the lighter scalar partners of top quarks ((t) over bar (1)) in 2.05 fb(-1) of pp collisions at root s = 7 TeV using the ATLAS experiment at the LHC are reported. Scalar top quarks are searched for in events with two same flavour opposite-sign leptons (e, mu) with invariant mass consistent with the Z boson mass, large missing transverse momentum and jets in the final state. At least one of the jets is identified as originating from a b-quark. No excess over Standard Model expectations is found. The results are interpreted in the framework of R-parity conserving, gauge mediated Supersymmetry breaking 'natural' scenarios, where the neutralino ((chi) over bar (0)(1)) is the next-to-lightest supersymmetric particle. Scalar top quark masses up to 310 GeV are excluded for 115 GeV m(<(chi) over bar1)(0) 230 GeV at 95% confidence level, reaching an exclusion of m(<(t) over bar1) 330 GeV for m(<(chi) over bar1)(0) = 190 GeV. Scalar top quark masses below 240 GeV are excluded for all values of m((chi) over bar1)(0) > m(z). (c) 2012 CERN. Published by Elsevier B.V. All rights reserved. RI Wemans, Andre/A-6738-2012; de Groot, Nicolo/A-2675-2009; valente, paolo/A-6640-2010; Takai, Helio/C-3301-2012; Delmastro, Marco/I-5599-2012; Livan, Michele/D-7531-2012
2012
The results of a search for pair production of the lighter scalar partners of top quarks ((t) over bar (1)) in 2.05 fb(-1) of pp collisions at root s = 7 TeV using the ATLAS experiment at the LHC are reported. Scalar top quarks are searched for in events with two same flavour opposite-sign leptons (e, mu) with invariant mass consistent with the Z boson mass, large missing transverse momentum and jets in the final state. At least one of the jets is identified as originating from a b-quark. No excess over Standard Model expectations is found. The results are interpreted in the framework of R-parity conserving, gauge mediated Supersymmetry breaking 'natural' scenarios, where the neutralino ((chi) over bar (0)(1)) is the next-to-lightest supersymmetric particle. Scalar top quark masses up to 310 GeV are excluded for 115 GeV m(<(chi) over bar1)(0) 230 GeV at 95% confidence level, reaching an exclusion of m(<(t) over bar1) 330 GeV for m(<(chi) over bar1)(0) = 190 GeV. Scalar top quark masses below 240 GeV are excluded for all values of m((chi) over bar1)(0) > m(z). (c) 2012 CERN. Published by Elsevier B.V. All rights reserved. RI Wemans, Andre/A-6738-2012; de Groot, Nicolo/A-2675-2009; valente, paolo/A-6640-2010; Takai, Helio/C-3301-2012; Delmastro, Marco/I-5599-2012; Livan, Michele/D-7531-2012
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.11770/145359
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