Threshold resummation effects in Higgs boson pair production at the LHC

TL;DR

Higgs boson pair production via gluon fusion at the LHC is challenged by large higher-order QCD corrections. The authors apply threshold resummation in SCET to NNLL accuracy, incorporating pi^2-enhanced terms and matching to NLO, while retaining exact top-mass form factors where possible. They find that resummation increases the NLO cross section by about 20–30% and reduces scale uncertainties to roughly 8% (with PDF uncertainties largely unchanged), with substantial improvements in invariant-mass distributions and rapidity predictions. The results also demonstrate strong sensitivity of the cross section and distributions to the Higgs self-coupling, suggesting that future precision measurements could extract lambda more reliably, albeit with residual top-mass uncertainties until full NLO mass effects are included.

Abstract

We investigate the resummation effects in the Standard Model Higgs boson pair production through gluon-gluon fusion at the LHC with soft-collinear effective theory. We calculate the total cross section and the invariant mass distribution at Next-to-Next-to-Leading-Logarithmic level with $π^2$-enhanced terms resummed, which are matched to the QCD Next-to-Leading Order results. In the high order QCD predictions exact top quark mass effects are included in full form factors. Our results show that the resummation effects increase the Next-to-Leading Order results by about $20% \sim 30%$, and the scale uncertainty is reduced to 8%, which lead to increased confidence on the theoretical predictions. The PDF+$\as$ uncertainties are almost not changed after including resummation effects. We also study the sensitivities of the total cross section and the invariant mass distribution to the Higgs boson self-coupling. We find that the total cross section and the invariant mass distribution shape depend strongly on the Higgs boson self-coupling, and therefore it is possible to extract Higgs boson self-coupling from the total cross section and invariant mass distribution when the measurement precision increases at the LHC.

Figures (14)

• Figure 1: Feynman diagrams for Higgs boson pair production induced by top quark loop at the Born level.
• Figure 2: Feynman diagrams for Higgs boson pair production at the tree level in the infinite top quark mass limit.
• Figure 3: Feynman diagrams for Higgs boson pair production at the NLO in the infinite top quark mass limit.
• Figure 4: A part of virtual corrections for Higgs boson pair production at the NLO in the infinite top quark mass limit, which have neither ultraviolet nor infrared divergences.
• Figure 5: Comparison of the NLO results and singular terms contributions to the total cross section (Left) and the invariant mass distributions (Right) for Higgs boson pair production at the LHC with $\sqrt{S}=14$ TeV. The PDF set MSTW2008NNLO and associated strong coupling constant $\alpha_s$ are used. The factorization scale is chosen as Higgs boson pair invariant mass. The other SM input parameters are shown in Eq. (\ref{['sminput']}).