Searching for GeV-scale Majorana Dark Matter: inter spem et metum

bstract We suggest a minimal model for GeV-scale Majorana Dark Matter (DM) coupled to the standard model lepton sector via a charged scalar singlet. We show that there is an anti-correlation between the spin-independent DM-Nucleus scattering cross section ( σ SI ) and the DM relic density for parameters values allowed by various theoretical and experimental constraints. Moreover, we find that even when DM couplings are of order unity, σ SI is below the current experimental bound but above the neutrino floor. Furthermore, we show that the considered model can be probed at high energy lepton colliders using e.g. the mono-Higgs production and same-sign charged Higgs pair production.