Constraining Gluonic Contact Interaction of a Neutrino-philic Dark Fermion at Hadron Colliders and Direct Detection Experiments

Abstract: Weakly interacting fermions with the Standard Model particles are promising candidates for the dark matter. In this paper, we study signatures of the gluonic interactions of a dark fermion and a neutrino at hadron colliders and direct detection experiments. The lowest order interactions are described by contact operators in dimension 7. At hadron colliders, the mono-jet production is the most sensitive channel. And these operators can also induce both spin-independent and spin-dependent absorption of the dark fermion at nuclear targets. We show that for a nearly massless dark fermion, the energy scales are constrained to be higher than 500 GeV and 1.2 TeV by the current LHC and HE-LHC searches, respectively. Furthermore, we also find that almost all the parameter space accessible by the spin-independent absorption has been excluded by the current LHC constraints. In contrast, for spin-dependent absorption at light nuclear targets there is still some parameter space which cannot be reached by current and upcoming LHC searches.