Invisible Z ′ and dark matter: LHC vs LUX constraints

We consider a simple, yet generic scenario in which a new heavy Z0 gauge boson couples both to SM fermions and to dark matter. In this framework we confront the best LHC limits on an extra gauge boson Z0 to the constraints on couplings to dark matter from direct detection experiments. In particular we show that the LHC searches for resonant production of dileptons and the recent exclusion limits obtained by the LUX collaboration give complementary constraints. Together, they impose strong bounds on the invisible branching ratio and exclude a large part of the parameter space for generic Z0 models. Our study encompasses many possible Z0 models, including SSM, E6-inspired or B-L scenario.peerReviewe