Higher-Order QCD prediction for dark matter pair associated with a b-jet production at the LHC

Dark matter associated visible particle production at high energy colliders provides a unique way to determine the microscopic properties of the dark matter. We investigate a pair of fermionic dark matter particles associated with a b-jet production at the LHC, through a mediator which couples to standard model or dark matter particles via either a vector or axial-vector coupling. The calculation is performed by implementing these simplified models in the FeynRules/MadGraph5 aMC@NLO framework. In our calculation, next-to-leading order QCD corrections and parton-shower effects are considered. We find that this process has a sizeable cross section and the QCD correction can reach more than 2 times than LO results. We also investigate the discovery potential in several benchmark scenarios at the 13TeV LHC.