Closing up on dark sectors at colliders: From 14 to 100 TeV

Abstract

We investigate the reach of the LHC Run 2 and that of a future circular hadron collider with up to 100 TeV center of mass energy for the exploration of potential dark matter sectors. These dark sectors are conveniently and broadly described by simplified models. The simplified models we consider provide microscopic descriptions of interactions between the standard model partons and the dark sector particles mediated by the four basic types of (s-channel) messenger fields: scalar, pseudoscalar, vector or axialvector. Our analysis extends and updates the previously available results for the LHC at 8 and 14 TeV to 100 TeV for models with all four messenger types. We revisit and improve the analysis at 14 TeV, by studying a variety of analysis techniques, concluding that the most discriminating variables correspond to the missing transverse energy and the azimuthal angle between jets in the final state. Going to 100 TeV, the limits on simplified models of dark matter are enhanced significantly, in particular for heavier mediators and dark sector particles, for which the available phase space at the LHC is restricted. The possibility of a 100 TeV collider provides an unprecedented coverage of the dark sector basic parameters and a unique opportunity to pin down the particle nature of dark matter and its interactions with the standard model.

Search for dark matter in proton-proton collisions at 8 TeV with missing transverse momentum and vector boson tagged jets

“…For the scalar mediator model, it is assumed that only heavy quarks (top and bottom) contribute. Such a choice limits the sensitivity for DD experiments, however, it allows the direct comparison between collider and DD experiments without an additional assumption for the light-quark couplings [100]. For the vector and scalar models, the limits are compared with those from the LUX [102], CDMS lite [103], CRESST II [104], and PandaX II [105] experiments.…”

Search for new physics in final states with an energetic jet or a hadronically decaying W or Z boson and transverse momentum imbalance at sSirunyan1, Tumasyan2, Adam3 et al. 2018Phys. Rev. D15011500View full textAdd to dashboardCite

“…In addition to interpretations in the context of simplified DM models [17][18][19], in this paper the results are further studied in the context of the fermion portal (FP) dark matter model [20], the light nonthermal DM model [21,22], and the ADD model. In many simplified DM models, DM particles are assumed to be Dirac fermions that interact with SM particles through a spin-1 or spin-0 mediator [18,20,[23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38]. These interactions are classified into four different types, depending on whether the mediator is a vector, axial-vector, scalar, or pseudoscalar particle.…”

Vector boson fusion searches for dark matter at the LHC

“…We note that production of the scalar and pseudoscalar mediators proceeds through a loop of top quarks. For heavy mediators at high p T , the correct differential spectrum can only been obtained if the top-quark loop is resolved, rather than treated as an effective interaction as it is in MadGraph [37,[72][73][74]. However, the VBF topology allows lower / E T thresholds to be present in analysis selection compared to typical mono-X searches, and we expect the correction factor from the resolved loop to be small.…”