Reanalysis of the Higgs boson decay H → gg up to -order level using the principle of maximum conformality

Abstract

Using the newly available -order QCD correction to the Higgs decay channel H → gg, we carry out a detailed discussion on the perturbative properties of the decay width Γ(H → gg) using the principle of maximum conformality (PMC). The PMC provides a way to eliminate the conventional renormalization scheme-and-scale ambiguities, which uses the renormalization group equation to determine the optimal running behavior of the strong coupling constant at each order via a recursive way. Even though there is no ambiguity for setting the renormalization scale, there is residual scale dependence for the PMC predictions due to unknown high-order terms. Using the -order terms, the somewhat larger residual renormalization scale dependence at the -order level observed in our previous work can be greatly suppressed, which shows KeV, where the first error is caused by the Higgs mass uncertainty ΔMH = 0.24 GeV, the second one is the residual scale dependence by varying the initial choice of scale within the region of , and the third one is the conservative prediction of unknown high-order contributions.