Paper detail

Prospect for Study of Randall-Sundrum model from Higgs decay at future colliders

In a class of Randall-Sundrum(RS) models, matter fermions and gauge bosons live in a five dimensional bulk, while the Higgs boson lives in a four dimensional visible brane. The Higgs boson can mix with a radion, by a Higgs-radion mixing term. It is difficult to directly discover the heavy Kaluza-Klein(KK) particles at the Large Hadron Collider(LHC), because the mass of the lightest KK particle is expected to be above 10 TeV to satisfy constraints from avor changing neutral currents(FCNC). Instead, the precision measurements of the Higgs sector at the high luminosity LHC(HL-LHC) and the International Linear Collider(ILC) is a promising way to observe the deviation originating from the Higgs-radion mixing and radiative corrections from the KK gauge bosons and matter fermions. For some cases, those effects are separately determined, providing valuable information on the model. We perform an extensive scan of the model parameters to see the expected deviations of the Higgs couplings. We also choose several reference points consistent with the current data to show the precision of the fundamental parameter measurements at the future colliders. We also study the radion-Z-Z coupling in the model and discuss the role of the ILC for radion search.