Studies of new Higgs boson interactions through nonresonant $HH$ production in the $b\bar{b}\gamma \gamma$ final state in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

Abstract

A search for nonresonant Higgs boson pair production in the $b\bar{b}\gamma \gamma$ final state is performed using 140 fb${}^{-1}$ of proton-proton collisions at a centre-of-mass energy of 13 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. This analysis supersedes and expands upon the previous nonresonant ATLAS results in this final state based on the same data sample. The analysis strategy is optimised to probe anomalous values not only of the Higgs ($H$) boson self-coupling modifier ${\kappa }_{\lambda }$ but also of the quartic $HHVV$ ($V=W,Z$) coupling modifier ${\kappa }_{2V}$. No significant excess above the expected background from Standard Model processes is observed. An observed upper limit ${\mu }_{HH}<4.0$ is set at 95% confidence level on the Higgs boson pair production cross-section normalised to its Standard Model prediction. The 95% confidence intervals for the coupling modifiers are $-1.4<{\kappa }_{\lambda }<6.9$ and $-0.5<{\kappa }_{2V}<2.7$, assuming all other Higgs boson couplings except the one under study are fixed to the Standard Model predictions. The results are interpreted in the Standard Model effective field theory and Higgs effective field theory frameworks in terms of constraints on the couplings of anomalous Higgs boson (self-)interactions.

47 pages in total, author list starting page 30, 9 figures, 6 tables, submitted to JHEP. All figures and tables including auxiliary figures and tables are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HDBS-2021-10/

References in corpus (8)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• An Introduction to PYTHIA 8.2
• Matching NLO QCD computations with Parton Shower simulations: the POWHEG method
• Higgs boson production in association with top quarks in the POWHEG BOX
• Automated one-loop computations in the SMEFT
• Vector-Boson Fusion Higgs Pair Production at N${}^3$LO
• $gg\to HH$: Combined Uncertainties
• Probing the trilinear Higgs boson coupling in di-Higgs production at NLO QCD including parton shower effects

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• Study of Higgs boson pair production in the $HH\to b\overline{b}\gamma \gamma$ final state with 308 fb${}^{-1}$ of data collected at $\sqrt{s}=$ 13 TeV and 13.6 TeV by the ATLAS experiment
• Probing new physics in the Boosted $HH\to b\bar{b}\gamma \gamma$ channel at the LHC
• Electroweak Higgs boson pair production: Updated inclusive cross sections