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ATLAS Collaboration(Aad, G. et al), Aikot, A., Amos, K. R., Bouchhar, N., Cabrera Urban, S., Cantero, J., et al. (2026). Study of Higgs boson pair production in the HH → b(b)over-barγγ final state with 308 fb-1 of data collected at √s=13 TeV and 13.6 TeV by the ATLAS experiment. Phys. Lett. B, 876, 140280–21pp.
Abstract: A search for Higgs boson pair production in the b (b) over bar gamma gamma final state is performed. The proton-proton collision dataset corresponds to an integrated luminosity of 308 fb-1, consisting of two samples, 140 fb(-1) at a centre-of-mass energy of root s = 13 TeV and 168 fb(-1) at root s = 13.6 TeV, recorded between 2015 and 2024 by the ATLAS detector at the CERN Large Hadron Collider. In addition to a larger dataset, this analysis improves upon the previous search in the same final state through several methodological and technical developments. The Higgs boson pair production cross section divided by the Standard Model prediction is found to be mu(HH) = 0.9(-1.1)(+1.4) (mu(HH) = 1(-1.0)(+1.3) expected), which translates into a 95% confidence-level upper limit of mu(HH) < 3.7. At the same confidence level the Higgs self-coupling modifier is constrained to be in the range -1.6 < kappa(lambda) < 6.6 (-1.8 < kappa(lambda) < 6.9 expected).
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ATLAS Collaboration(Aad, G. et al), Amoros, G., Cabrera Urban, S., Castillo Gimenez, V., Costa, M. J., Escobar, C., et al. (2012). Measurement of the cross-section for b-jets produced in association with a Z boson at root s=7 TeV with the ATLAS detector ATLAS Collaboration. Phys. Lett. B, 706(4-5), 295–313.
Abstract: A measurement is presented of the inclusive cross-section for b-jet production in association with a Z boson in pp collisions at a centre-of-mass energy of root s = 7 TeV. The analysis uses the data sample collected by the ATLAS experiment in 2010, corresponding to an integrated luminosity of approximately 36 pb(-1). The event selection requires a Z boson decaying into high P-T electrons or muons, and at least one b-jet, identified by its displaced vertex, with transverse momentum p(T) > 25 GeV and rapidity vertical bar y vertical bar < 2.1. After subtraction of background processes, the yield is extracted from the vertex mass distribution of the candidate b-jets. The ratio of this cross-section to the inclusive Z cross-section (the average number of b-jets per Z event) is also measured. Both results are found to be in good agreement with perturbative QCD predictions at next-to-leading order.
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