Co-annihilating Dark Matter: Effective Operator Analysis and Collider Phenomenology

NICOLE F. BELL, YI CAI, ANIBAL D. MEDINA

PHYSICAL REVIEW D

AMER PHYSICAL SOC

Lugar: New York; Año: 2014

1550-7998

We study dark matter (DM) models in which there are two dark sector particles, 1 and 2, of near mass. In such models, co-annihilation of 1 and 2 may be the dominant process controlling the DM relic density during freezeout in the early universe. In this scenario, there is no signicant contribution to direct and indirect detection signals, unless there exists an extreme degeneracy in the masses of the lightest dark sector particles. Therefore, relic density constraints and collider searches provide the most relevant information about these models. We consider Dirac fermion dark matter which couples to standard model (SM) particles via an eective operator. For the collider phenomenology, where an eective eld theory may not be valid, we adopt a simple Z´ model to provide an appropriate UV completion. We explore the interesting LHC signals that arise from the dark matter production process pp to 1 + 2 + jet, followed by the decay 2 to 1 + SM.