Effective field theory for top physics

We study the top forward-backward asymmetry (FBA $\equiv A_{\mathrm{F}\mathrm{B}}$) reported by CDF and D0 Collaborations in the effective lagrangian approach. Using dimension-6 effective largrangians for $q\bar{q}\to t\bar{t}$, we study the $t\bar{t}$ production cross section and the $A_{\mathrm{F}\mathrm{B}}$, and a few observables: the FB spin-spin correlation that is strongly correlated with the $A_{\mathrm{F}\mathrm{B}}$, and longitudinal top polarization as a new probe of chiral structures for possible new physics scenarios.