Model-independent analysis of top quark forward-backward asymmetry at the Tevatron up to O(αs2/Λ2)

We present the complete calculations of the forward-backward asymmetry (AFB) and the total cross section of top quark pair production induced by dimension-six four quark operators at the Tevatron up to O(αs2/Λ2). Our results show that next-to-leading order QCD corrections can change AFB and the total cross section by about 10%. Moreover, next-to-leading order QCD corrections reduce the dependence of AFB and total cross section on the renormalization and factorization scales significantly. We also evaluate the total cross section and the charge asymmetry (AC) induced by these operators at the Large Hadron Collider (LHC) up to O(αs2/Λ2), for the parameter space allowed by the Tevatron data. We find that the value of AC induced by these operators is much larger than standard model prediction, and LHC has potential to discover these new physics effects when the measurement precision increases.