Triple Higgs Boson Production with Two Heavy Scalars at the LHC via a Simplified Approach

Abstract: We investigate triple Higgs boson production at the CERN LHC, in models containing two new neutral scalar particles heavier than the Higgs boson. We apply a simplified factorized approach in the narrow-width approximation to double-resonant triple Higgs boson production, and demonstrate that relevant constraints can be derived on models with extended scalar sectors, during the high-luminosity phase of the LHC. We also show that analyzing the double-resonant process will be sufficient at the LHC, within an explicit model with two real singlet scalar fields, and that non-resonant components are not expected to play a crucial role in the specific scenario. The method can be applied to any model where triple Higgs boson production can be enhanced via the double-resonant process in the presence of two new neutral scalar resonances.