Radiative corrections to the Higgs boson couplings in the triplet model

We calculate a full set of one-loop corrections to the Higgs boson coupling constants as well as the electroweak parameters. We compute the decay rate of the standard model-like Higgs boson (h) into diphoton. Renormalized Higgs couplings with the weak gauge bosons hVV (V = W and Z) and the trilinear coupling hhh are also calculated at the one-loop level in the on-shell scheme. Magnitudes of the deviations in these quantities are evaluated in the parameter regions where the unitarity and vacuum stability bounds are satisfied and the predicted W boson mass at the one-loop level is consistent with the data. We find that there are strong correlations among deviations in the Higgs boson couplings h gamma gamma, hVV and hhh. For example, if the event number of the pp -> h -> gamma gamma channel deviates by +30% (- 40%) from the standard model prediction, deviations in the one-loop corrected hVV and hhh vertices are predicted to be about -0.1% (- 2%) and -10% ( + 150%), respectively. The model can be discriminated from the other models by accurately measuring these coupling constants in future collider experiments. DOI: 10.1103/PhysRevD.87.015012