Abstract
We introduce a set of minimal simplified models for dark matter interactions
with the Standard Model, connecting the two sectors via either a scalar or
pseudoscalar particle. These models have a wider regime of validity for dark
matter searches at the LHC than the effective field theory approach, while
still allowing straightforward comparison to results from non-collider dark
matter detection experiments. Such models also motivate dark matter searches in
multiple correlated channels. In this paper, we constrain scalar and
pseudoscalar simplified models with direct and indirect detection experiments,
as well as from existing LHC searches with missing energy plus tops, bottoms,
or jets, using the exact loop-induced coupling with gluons. This calculation
significantly affects key differential cross sections at the LHC, and must be
properly included. We make connections with the Higgs sector, and conclude with
a discussion of future searches at the LHC.