Measurement of the H → γ γ and H → Z Z ∗ → 4 ℓ cross-sections in pp collisions at s = 13.6 TeV with the ATLAS detector

UNSPECIFIED (2024) Measurement of the H → γ γ and H → Z Z ∗ → 4 ℓ cross-sections in pp collisions at s = 13.6 TeV with the ATLAS detector. European Physical Journal C: Particles and Fields, 84 (1): 78. ISSN 1434-6044

Abstract

The inclusive Higgs boson production cross-section is measured in the di-photon and the ZZ∗→4ℓ decay channels using 31.4 and 29.0 fb-1 of pp collision data respectively, collected with the ATLAS detector at a centre-of-mass energy of s=13.6 TeV. To reduce the model dependence, the measurement in each channel is restricted to a particle-level phase space that closely matches the channel’s detector-level kinematic selection, and it is corrected for detector effects. These measured fiducial cross-sections are σfid, γγ= 76-13+14 fb, and σfid, 4ℓ= 2.80±0.74 fb, in agreement with the corresponding Standard Model predictions of 67.6±3.7 fb and 3.67±0.19 fb. Assuming Standard Model acceptances and branching fractions for the two channels, the fiducial measurements are extrapolated to the full phase space yielding total cross-sections of σ(pp→H)=67-11+12 pb and 46±12 pb at 13.6 TeV from the di-photon and ZZ∗→4ℓ measurements respectively. The two measurements are combined into a total cross-section measurement of σ(pp→H)=58.2±8.7 pb, to be compared with the Standard Model prediction of σ(pp→H)SM=59.9±2.6 pb.