A minimal model for SU(N) vector dark matter

Abstract

We study an extension of the Standard Model featuring a hidden sector that consists of a new scalar charged under a new SU(N)D gauge group , singlet under all Standard Model gauge interactions, and coupled with the Standard Model only via a Higgs portal. We assume that the theory is classically conformal, with electroweak symmetry breaking dynamically induced via the Coleman-Weinberg mechanism operating in the hidden sector. Due to the symmetry breaking pattern, the SU(N)D gauge group is completely Higgsed and the resulting massive vectors of the hidden sector constitute a stable dark matter candidate. We perform a thorough scan over the parameter space of the model at different values of N = 2, 3, and 4, and investigate the phenomenological constraints. We find that N = 2, 3 provide the most appealing model setting in light of present data from colliders and dark matter direct search experiments. We expect a heavy Higgs to be discovered at LHC by the end of Run II or the N = 3 model to be ruled out.