Study of High-Transverse-Momentum Higgs Boson Production in Association with a Vector Boson in the qqbb Final State with the ATLAS Detector

This Letter presents the first study of Higgs boson production in association with a vector boson (𝑉 = 𝑊 or 𝑍) in the fully hadronic 𝑞⁢𝑞⁢𝑏⁢𝑏 final state using data recorded by the ATLAS detector at the LHC in proton-proton collisions at √𝑠 = 13  TeV and corresponding to an integrated luminosity of 137  fb⁻¹. The vector bosons and Higgs bosons are each reconstructed as large-radius jets and tagged using jet substructure techniques. Dedicated tagging algorithms exploiting 𝑏-tagging properties are used to identify jets consistent with Higgs bosons decaying into 𝑏𝑏⁢¯. Dominant backgrounds from multijet production are determined directly from the data, and a likelihood fit to the jet mass distribution of Higgs boson candidates is used to extract the number of signal events. The 𝑉⁢𝐻 production cross section is measured inclusively and differentially in several ranges of Higgs boson transverse momentum: 250–450, 450–650, and greater than 650 GeV. The inclusive signal yield relative to the standard model expectation is observed to be 𝜇=1.4^+1.0_−0.9 and the corresponding cross section is 3.1±1.3⁢(stat)^+1.8_−1.4⁢(syst)  pb.