PHYSICAL REVIEW LETTERS, cilt.133, sa.10, 2024 (SCI-Expanded, Scopus)
This Letter presents results from a combination of searches for Higgs boson pair production using 126-140 fb(-1) of proton-proton collision data at root s = 13 TeV recorded with the ATLAS detector. At 95% confidence level (CL), the upper limit on the production rate is 2.9 times the standard model (SM) prediction, with an expected limit of 2.4 assuming no Higgs boson pair production. Constraints on the Higgs boson self-coupling modifier kappa(lambda) =lambda(HHH) /lambda(SM)(HHH), and the quartic HHVV coupling modifier kappa(2V) = g(HHVV)/g(HHVV)(SM), are derived individually, fixing the other parameter to its SM value. The observed 95% CL intervals are -1.2