A search is presented for new phenomena in events characterised by high jet multiplicity, no leptons (electrons or muons), and four or more jets originating from the fragmentation of b-quarks (b-jets). The search uses 139 fb −1 of \sqrt{s} = 13 TeV proton–proton collision data collected by the ATLAS experiment at the Large Hadron Collider during Run 2. The dominant Standard Model background originates from multijet production and is estimated using a data-driven technique based on an extrapolation from events with low b-jet multiplicity to the high b-jet multiplicities used in the search. No significant excess over the Standard Model expectation is observed and 95% confidence-level limits that constrain simplified models of R-parity-violating supersymmetry are determined. The exclusion limits reach 950 GeV in top-squark mass in the models considered.

Search for phenomena beyond the Standard Model in events with large b-jet multiplicity using the ATLAS detector at the LHC

Farina E. M.;Introzzi G.;Livan M.;Negri A.;Pezzotti L.;Rebuzzi D. M.;Rimoldi A.;Rovelli G.;