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

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 139fb(-1)of s root = 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.

Automated summary

A search for new phenomena characterized by high jet multiplicity, no leptons, and four or more jets originating from b-quarks has been conducted using data collected by the ATLAS experiment at the Large Hadron Collider. No significant excess over the Standard Model expectation was observed, and exclusion limits on simplified models of R-parity-violating supersymmetry were determined, reaching up to 950 GeV in top-squark mass in the considered models.