Measurement of top quark polarization in dileptonic top-antitop quark events using the ATLAS detector

We perform a measurement of the product top quark polarization and leptonic spin analyzing power in\nthe dilepton channel of top-antitop production. The analysis is based\non 4.66 fb^-1 of ATLAS data taken at sqrt(s) = 7 TeV at the Large\nHadron Collider. While in the Standard Model the polarization is\npredicted to be negligible, it can take non-zero values in several\ntheory models beyond the Standard Model. A CP conserving and a CP\nviolating scenario are probed as new physics production processes by creating templates for the angular\ndistribution of the charged leptons with respect to the top direction.\nTo reconstruct the ttbar system in the dilepton channel a neutrino\nweighting technique is used . The extracted polarization is consistent\nwith the prediction from the Standard Model.