Precision study of $W^-W^+H$ production including parton shower effects at the CERN Large Hadron Collider

Abstract

The precision study of $W^-W^+H$ production with subsequent $W^{\pm} \rightarrow l^{\pm} \overset{ _{(-)}}{\nu_{l}}$ and $H \rightarrow b\bar{b}$ decays at the LHC can help us to study the Higgs gauge couplings and to search for new physics beyond the SM. In this paper, we calculate the shower-matched NLO QCD correction and the EW corrections from the $q\bar{q}$ annihilation and photon-induced channels to the $W^-W^+H$ production at the $14~ {\rm TeV}$ LHC, and deal with the subsequent decays of Higgs and $W^{\pm}$ bosons by adopting the {\sc MadSpin} method. Both the integrated cross section and some kinematic distributions of $W^{\pm}$, $H$ and their decay products are provided. We find that the QCD correction enhances the LO differential cross section significantly, while the EW correction from the $q\bar{q}$ annihilation channel obviously suppresses the LO differential cross section, especially in the high energy phase-space region due to the Sudakov effect. The $q\gamma$- and $\gamma\gamma$-induced relative corrections are positive, and insensitive to the transverse momenta of $W^{\pm}$, $H$ and their decay products. These photon-induced corrections compensate the negative $q\bar{q}$-initiated EW correction, and become the dominant EW contribution as the increment of the $pp$ colliding energy. The parton shower (PS) effects on the kinematic distributions are nonnegligible. The PS relative correction to the $b$-jet transverse momentum distribution can exceed $100\%$ in the high $p_{T, b}$ region. We also investigate the scale and PDF uncertainties, and find that the theoretical error of the ${\rm QCD}+{\rm EW}+q\gamma+\gamma\gamma$ corrected integrated cross section mainly comes from the renormalization scale dependence of the QCD correction.