Spin Correlation in ${{\boldsymbol t}}{{\overline{\boldsymbol t}}}$ Production in ${{\boldsymbol p}}{{\overline{\boldsymbol p}}}$ Collisions
INSPIRE search
C is the correlation strength parameter, f is the ratio of events with correlated ${{\mathit t}}$ and ${{\overline{\mathit t}}}$ spins (SM prediction: f = 1), and $\kappa $ is the spin correlation coefficient. See "The Top Quark" review for more information.