Measurements of the Higgs boson production, fiducial and differential cross-sections in the four lepton decay channel using 164 fb−1 of data collected at s=13.6 TeV with the ATLAS detector

Inclusive, differential and production-mode cross-section measurements of the Higgs boson are performed in the H → ZZ^* → 4ℓ decay channel. The analysis uses proton–proton collision data produced at the Large Hadron Collider at a centre-of-mass energy of s=13.6 TeV and recorded with the ATLAS detector, corresponding to an integrated luminosity of 164 fb⁻¹. The inclusive fiducial cross-section for the H → ZZ^* → 4ℓ process is measured to be σfid=3.65−0.33+0.35 fb, in agreement with the Standard Model prediction of σfidSM=3.68±0.17 fb. Differential cross-sections are measured as a function of key kinematic observables of the Higgs boson and the four-lepton final state. Cross-sections are measured for the main production-modes in several exclusive regions of the Higgs boson production phase space and combined to measure an overall Higgs boson signal strength, defined as the measured cross-section normalised to the SM prediction, of μ = 0.99 ± 0.13. The results are interpreted in terms of modifications of Higgs boson couplings using the κ framework, within the Standard Model Effective Field Theory, and in scenarios probing the Higgs boson self-coupling. All the results are consistent with Standard Model expectations.