The ATLAS collaboration published the results of searching for the associative production of a Higgs boson and a top–antitop quark pair. Investigations were performed using the data collected in the channels of the Higgs boson decay into \(b\bar b\), WW∗, τ+τ−, γγ and ZZ∗over the entire LHC operation period. The production was observed with the statistical significance of 6.3 standard deviations at the expectation of 5.1 within the Standard Model. It is a pleasure to point out that DLNP scientists take an active part in this analysis, dealing with the channel of the Higgs boson decay into τ+τ−.

 Combined tt̄H production cross section, as well as cross sections measured in the individual analyses, divided by the SM prediction. The γγ and ZZ* → 4ℓ analyses use 13 TeV data corresponding to an integrated luminosity of 79.8 fb-1, and the multilepton and bb̄ analyses use data corresponding to an integrated luminosity of 36.1 fb-1. The black lines show the total uncertainties, and the bands indicate the statistical and systematic uncertainties. The red vertical line indicates the SM cross-section prediction, and the grey band represents the PDF+αSuncertainties and the uncertainties due to missing higher-order corrections. 

 Measured total tt̄H production cross sections at 13 TeV, as well as observed (Obs.) and expected (Exp.) significances (sign.) relative to the background-only hypothesis. The results of the individual analyses, as well as the combined results are shown. Since no event is observed in the H → ZZ* → 4ℓ decay channel, an observed upper limit is set at 68% confidence level on the tt̄H production cross section in that channel using pseudo-experiments.