Search for a CP-odd Higgs boson decaying into a heavy CP-even Higgs boson and a Z boson in the ℓ+ℓ−tt¯ and νν¯bb¯ final states using 140 fb−1 of data collected with the ATLAS detector

Summary, in English

A search for a heavy CP-odd Higgs boson, A, decaying into a Z boson and a heavy CP-even Higgs boson, H, is presented. It uses the full LHC Run 2 dataset of pp collisions at s = 13 TeV collected with the ATLAS detector, corresponding to an integrated luminosity of 140 fb−1. The search for A → ZH is performed in the ℓ+ℓ−tt¯ and νν¯bb¯ final states and surpasses the reach of previous searches in different final states in the region with mH > 350 GeV and mA > 800 GeV. No significant deviation from the Standard Model expectation is found. Upper limits are placed on the production cross-section times the decay branching ratios. Limits with less model dependence are also presented as functions of the reconstructed m(tt¯) and m(bb¯) distributions in the ℓ+ℓ−tt¯ and νν¯bb¯ channels, respectively. In addition, the results are interpreted in the context of two-Higgs-doublet models.

• Author: G. Aad; T.P.A. Åkesson; C. Doglioni; P.A. Ekman; V. Hedberg; H. Herde; B. Konya; E. Lytken; R. Poettgen; N.D. Simpson; O. Smirnova; L. Zwalinski
• Department/s: Particle and nuclear physics; eSSENCE: The e-Science Collaboration; Department of Physics
• Publishing year: 2024
• Language: English
• Publication/Series: Journal of High Energy Physics
• Volume: 2024
• Issue: 2
• Links: http://dx.doi.org/10.1007/JHEP02(2024)197
• Document type: Journal article
• Publisher: Springer
• Topic: Subatomic Physics
• Keywords: Hadron-Hadron Scattering
• Status: Published
• ISBN/ISSN/Other: ISSN: 1029-8479