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The latest measurements of the asymmetry in the angular distributionsof the \ttbar\ events are reviewed. The measurements of the forward-backwardasymmetry \Afb\ in the \ppbar\ 1.98 TeV collisions at the Tevatronshow some tension with the Standard Model calculation, while resultsof the measurements of the charge asymmetry \Ac\ in $pp$ collisionsat 7 TeV and 8 TeV at the LHC are compatible with Standard Model predictions.

Here, we present a measurement of the correlation between the spins of t and tbar quarks produced in proton-antiproton collisions at the Tevatron Collider at a center-of-mass energy of 1.96 TeV. We apply a matrix element technique to dilepton and single-lepton+jets final states in data accumulated with the D0 detector that correspond to an integrated luminosity of 9.7 fb$$^{-1}$$. The measured value of the correlation coefficient in the off-diagonal basis, $$O_{off} = 0.89 \pm 0.22$$ (stat + syst), is in agreement with the standard model prediction, and represents evidence for a top-antitop quark spin correlation difference from zero at amore » level of 4.2 standard deviations.« less