Dark and bright signatures of di-Higgs boson production
Alexandre Alves (Departamento de Física, Universidade Federal de São Paulo, UNIFESP, Diadema, 09913-030, Brazil); Tathagata Ghosh (Department of Physics & Astronomy, University of Hawaii, Honolulu, Hawaii 96822, USA); Farinaldo S. Queiroz (International Institute of Physics, Universidade Federal do Rio Grande do Norte, Campus Universitário, Lagoa Nova, Natal-RN 59078-970, Brazil)
If the Higgs boson decays to a pair of invisible particles, the number of di-Higgs events, where each Higgs decays into Standard Model (SM) particles, is reduced by a factor of two-third taking into account the current LHC bound on invisible decay width of the Higgs boson. We investigate the sensitivity of the upcoming high luminosity run of the LHC to di-Higgs production and subsequent decay to dark matter in the context of the singlet scalar extension of the SM augmented by a fermionic dark matter in the dark and bright channel . Once systematic uncertainties on background yields are considered, this dark and bright channel presents competitive limits than after a careful tuning of the kinematical cuts that raise the signal over background ratio. We further show that in a multivariate analysis, for an invisible branching fraction as low as , we obtain stronger bounds for the Higgs trilinear coupling from the channel compared to the final state. Finally, we demonstrate that the four channels , , , and complement each other in the search for di-Higgs production with non-SM trilinear couplings when an invisible decay mode is present.