Search for triple Higgs boson production in the 6b final state using pp collisions at √s =13 TeV with the ATLAS detector

Abstract

A search for the production of three Higgs bosons (HHH) in the b-bb-bb-b final state is presented. Thesearch uses 126 fb-1 of proton-proton collision data atffiffiffisp1/4 13 TeV collected with the ATLAS detector atthe Large Hadron Collider. The analysis targets both nonresonant and resonant production of HHH. Theresonant interpretations primarily consider a cascade decay topology of X RIGHTWARDS ARROW SH RIGHTWARDS ARROW HHH with masses ofthe new scalars X and S up to 1.5 and 1 TeV, respectively. In addition to scenarios where S is off-shell, thenonresonant interpretation includes a search for Standard Model HHH production, with limits on thetrilinear and quartic Higgs self-coupling set. No evidence for HHH production is observed. An upper limitof 59 fb is set, at the 95% confidence level, on the cross section for Standard Model HHH production.