Top-flavored dark matter and the forward-backward asymmetry

Abstract

We propose a simple model where dark matter (DM) carries top flavor and couples to the Standard Model through the top quark within a framework of minimal flavor violation (MFV). Top-flavored DM can explain the anomalous top forward-backward asymmetry observed at the Tevatron, while remaining consistent with other top observables at colliders. By virtue of its large coupling to top, DM acquires a sizable loop coupling to the Z boson, and the relic density is set by annihilation through the Z. We also discuss contraints from current direct detection searches, emphasizing the role of spin-dependent searches to probe this scenario.