Report number
| ATL-PHYS-SLIDE-2024-045 |
Title
| DiHiggs searches (HH, XH) at ATLAS and CMS |
Author(s)
| D'Eramo, Louis (Université Clermont Auvergne (FR)) |
Corporate author(s)
| The ATLAS collaboration |
Collaboration
| ATLAS Collaboration |
Submitted to
| 58th Rencontres de Moriond on Electroweak Interactions and Unified Theories, La Thuile, Italy, 24 - 31 Mar 2024 |
Submitted by
| louis.d'eramo@cern.ch on 29 Mar 2024 |
Subject category
| Particle Physics - Experiment |
Accelerator/Facility, Experiment
| CERN LHC ; ATLAS |
Free keywords
| HH ; SH ; HDBS |
Abstract
| In the Standard Model, the ground state of the Higgs field is not found at zero but instead corresponds to one of the degenerate solutions minimising the Higgs potential. In turn, this spontaneous electroweak symmetry breaking provides a mechanism for the mass generation of nearly all fundamental particles. The Standard Model makes a definite prediction for the Higgs boson self-coupling and thereby the shape of the Higgs potential. Experimentally, both can be probed through the production of Higgs boson pairs (HH), a rare process that presently receives a lot of attention at the LHC. Additionally, several physics scenarios beyond the Standard Model predict the existence of new particles that can subsequently decay into a pair of Higgs bosons. These include pairs of SM-like Higgs bosons (HH) as well as asymmetric decays into two scalars of different masses (SH). In this talk, the latest HH searches by the ATLAS and CMS experiments are reported, with emphasis on the results obtained with the full LHC Run 2 dataset at 13 TeV. Non-resonant HH search results are interpreted both in terms of sensitivity to the Standard Model and as limits on the Higgs boson self-coupling and the quartic VVHH coupling. Further, HH searches can be exploited to put constraints on the Wilson coefficients of Effective Field Theories. The Higgs boson self-coupling can be also constrained by exploiting higher-order electroweak corrections to single Higgs boson production. A combined measurement of both results yields the overall highest precision, and reduces model dependence by allowing for the simultaneous determination of the single Higgs boson couplings. Results for this combined measurement are also presented. ATLAS searches for resonant HH and SH production are also presented. Finally, extrapolations of recent HH results towards the High Luminosity LHC upgrade are also discussed. |