Probing the Higgs portal at the LHC through resonant di-Higgs production

Abstract

We investigate resonant di-Higgs production as a means of probing extended scalar sectors that include a 125 GeV Standard Model-like Higgs boson. For concreteness, we consider a gauge singlet Higgs portal scenario leading to two mixed doublet-singlet states, h_(1,2). For m(_h_2)>2m(_h_1), the resonant di-Higgs production process pp→h_(2)→h_(1)h_(1) will lead to final states associated with the decaying pair of Standard Model-like Higgs scalars. We focus on h_(2) production via gluon fusion and on the bb^¯τ^(+)τ^(−) final state. We find that discovery of the h_(2) at the LHC may be achieved with ≲100  fb^(−1) of integrated luminosity for benchmark parameter choices relevant to cosmology. Our analysis directly maps onto the decoupling limit of the next-to-minimal supersymmetric Standard Model and more generically onto extensions of the Standard Model Higgs sector in which a heavy scalar produced through gluon-fusion decays to a pair of Standard Model-like Higgs bosons.