Measurement of Top Quark Polarization in Top-Antitop Events from Proton-Proton Collisions at s√=7  TeV Using the ATLAS Detector Aad, G. Aguilar Saavedra, Juan Antonio Atlas Collaboration Top quark Atlas detector Proton collisions This Letter presents measurements of the polarization of the top quark in top-antitop quark pair events, using 4.7  fb−1 of proton-proton collision data recorded with the ATLAS detector at the Large Hadron Collider at s√=7  TeV. Final states containing one or two isolated leptons (electrons or muons) and jets are considered. Two measurements of αℓP, the product of the leptonic spin-analyzing power and the top quark polarization, are performed assuming that the polarization is introduced by either a CP conserving or a maximally CP violating production process. The measurements obtained, αℓPCPC=−0.035±0.014(stat)±0.037(syst) and αℓPCPV=0.020±0.016(stat)+0.013−0.017(syst), are in good agreement with the standard model prediction of negligible top quark polarization. 2014-02-25T11:01:21Z 2014-02-25T11:01:21Z 2013 info:eu-repo/semantics/article Aad, G.; et al. Measurement of Top Quark Polarization in Top-Antitop Events from Proton-Proton Collisions at s√=7  TeV Using the ATLAS Detector. Physical Review Letters, 111: 232002 (2013). [http://hdl.handle.net/10481/30542] 0031-9007 1079-7114 doi: 10.1103/PhysRevLett.111.232002 http://hdl.handle.net/10481/30542 eng http://creativecommons.org/licenses/by-nc-nd/3.0/ info:eu-repo/semantics/openAccess Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License American Physical Society