Search for resonant pair production of Higgs bosons in the bb¯bb¯ final state using pp collisions at s√ = 13 TeV with the ATLAS detector

A search for resonant Higgs boson pair production in the ¯ ¯ final state is presented. The analysis uses 126–139 fb−1 of collision data at √ = 13 TeV collected with the ATLAS detector at the Large Hadron Collider. The analysis is divided into two channels, targeting Higgs boson decays which are reconstructed as pairs of small-radius jets or as individual large-radius jets. Spin-0 and spin-2 benchmark signal models are considered, both of which correspond to resonant production via gluon–gluon fusion. The data are consistent with Standard Model predictions. Upper limits are set on the production cross-section times branching ratio to Higgs boson pairs of a new resonance in the mass range from 251 GeV to 5 TeV