A search for pair-produced scalar or vector leptoquarks decaying into a b-quark and a τ -lepton is presented using the full LHC Run 2 (2015–2018) data sample of 139 fb−1 collected with the ATLAS detector in proton– proton collisions at a centre-of-mass energy of √s = 13 TeV. Events in which at least one τ -lepton decays hadronically are considered, and multivariate discriminants are used to extract the signals. No significant deviations from the Standard Model expectation are observed and 95% confidencelevel upper limits on the production cross-section are derived as a function of leptoquark mass and branching ratio B into a τ -lepton and b-quark. For scalar leptoquarks, masses below 1460 GeV are excluded assuming B = 100%, while for vector leptoquarks the corresponding limit is 1650 GeV (1910 GeV) in the minimal-coupling (Yang–Mills) scenario.

Aad, G., Abbott, B., Abeling, K., Abidi, S.H., Aboulhorma, A., Abramowicz, H., et al. (2023). Search for pair production of third-generation leptoquarks decaying into a bottom quark and a τ -lepton with the ATLAS detector. EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS, 83(11), 1075-1-1075-35 [10.1140/epjc/s10052-023-12104-7].

Search for pair production of third-generation leptoquarks decaying into a bottom quark and a τ -lepton with the ATLAS detector

Alberghi, G. L.;Alfonsi, F.;Bindi, M.;Boscherini, D.;Cabras, G.;Carratta, G.;Cavalli, N.;De Castro, S.;Fabbri, F.;Fabbri, L.;Franchini, M.;Gabrielli, A.;Massa, L.;