Strongly interacting dark sectors in the early Universe and at the LHC
  through a simplified portal
  We study the cosmology and LHC phenomenology of a consistent strongly
interacting dark sector coupled to Standard Model particles through a generic
vector mediator. We lay out the requirements for the model to be cosmologically
viable, identify annihilations into dark vector mesons as the dominant dark
matter freeze-out process and discuss bounds from direct detection. At the LHC
the model predicts dark showers, which can give rise to semi-visible jets or
displaced vertices. Existing searches for di-jet resonances and for missing
energy mostly probe the parameter regions where prompt decays are expected and
constrain our model despite not being optimised for dark showers. We also
estimate the sensitivity of dedicated analyses for semi-visible jets and
emphasize the complementarity of different search strategies.
