Search for resonant pair production of Higgs bosons in the 4b final state using 139 fb−1 of sqrt(s) = 13 TeV pp collision data with the ATLAS detector

A search for resonant Higgs boson pair production in the 4b final state is presented. The analysis uses up to 139 fb−1 of pp collision data at sqrt(s) = 13 TeV collected with the ATLAS detector. The analysis is divided into two categories, targeting Higgs boson decays which are reconstructed as pairs of jets or as single large-radius jets. Two benchmark signal models are considered: a scalar resonance and a spin-2 graviton, both of which are produced via gluon-gluon fusion. The observed data are consistent with Standard Model predictions. Upper limits are set on the production cross section times branching ratio of a new resonance in the mass range from 251 GeV to 5 TeV.