In the simplest Higgs-portal scalar dark matter model, the dark matter mass has been restricted to be either near the resonant mass (m h /2) or in a large-mass region by the direct detection at LHC Run 1 and LUX. While the large-mass region below roughly 3 TeV can be probed by the future Xenon1T experiment, most of the resonant mass region is beyond the scope of Xenon1T. In this paper, we study the direct detection of such scalar dark matter in the narrow resonant mass region at the 14 TeV LHC and the future 100 TeV hadron collider. We show the luminosities required for the 2σ exclusion and 5σ discovery.

The simplest Higgs-portal dark matter model, in which a real scalar singlet is added to the standard model, has been comprehensively revisited, by taking into account the constraints from perturbativity, electroweak vacuum stability in the early Universe, dark matter direct detection, and Higgs invisible decay at the LHC. We show that the resonant mass region is totally excluded and the high mass region is reduced to a narrow window 1.1 TeV ≤ m s ≤ 2.55 TeV, which is slightly reduced to 1.1 TeV ≤ m s ≤ 2.0 TeV if the perturbativity is further imposed. This high mass region can be fully detected by the Xenon1T experiment.

A constrained superfield formalism has been proposed in [10] to analyze the low energy physics related to Goldstinos. We prove that this formalism can be reformulated in the language of standard realization of nonlinear supersymmetry. New relations have been uncovered in the standard realization of nonlinear supersymmetry.

We update the parameter spaces for both a real and complex scalar dark matter via the Higgs portal. In the light of constraints arising from the LUX 2016 data, the latest Higgs invisible decay and the gamma ray spectrum, the dark matter resonant mass region is further restricted to a narrow window between 54.9−62.3 GeV in both cases, and its large mass region is excluded until 834 GeV and 3473 GeV for the real and complex scalar, respectively.