Tracking down the top quark forward-backward asymmetry with monotops

We revisit the possibility that the top quark forward-backward asymmetry arises from the on-shell production and decay of scalar top partners to t (t) over bar + E-T. Although the asymmetry is produced by t-channel exchange of a light mediator, the model remains unconstrained by low energy atomic parity violation tests. An interesting connection to the active neutrino sector through a type-I seesaw operator helps to evade stringent monojet constraints and opens up a richer collider phenomenology. After performing a global fit to top data from both the Tevatron and the LHC, we obtain a viable region of parameter space consistent with all phenomenological and collider constraints. We also discuss the discovery potential of a predicted monotop signal and related lepton charge asymmetry at the LHC.