Top quark forward-backward asymmetry and W′ bosons

The top quark forward-backward asymmetry measured at the Fermilab Tevatron collider deviates from the standard model prediction. A W' boson model is described, where the coupling W'-t-d is fixed by the t (t) over bar forward-backward asymmetry and total cross section at the Tevatron. We show that such a W' boson would be produced in association with a top quark at the CERN Large Hadron Collider (LHC), thus inducing additional t (t) over bar + j events. We use measurements of t (t) over bar + n-jet production from the LHC to constrain the allowed W'-t-d couplings as a function of W' boson mass. We find that this W' model is constrained at the 95% confidence level using 0.7 fb(1) of data from the LHC, and could be fully excluded with 5 fb(1) of data.