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arXiv · 2412.00570

Search for heavy neutral Higgs bosons A and H in the $\mathrm{t\bar{t}}$Z channel in proton-proton collisions at 13 TeV

CMS Collaboration
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Abstract

A direct search for new heavy neutral Higgs bosons A and H in the $\mathrm{t\bar{t}}$Z channel is presented, targeting the process pp $\to$ A $\to$ ZH with H $\to$ $\mathrm{t\bar{t}}$. For the first time, the channel with decays of the Z boson to muons or electrons in association with all-hadronic decays of the $\mathrm{t\bar{t}}$ system is targeted. The analysis uses proton-proton collision data collected at the CERN LHC with the CMS experiment at $\sqrt{s}$ = 13 TeV, which correspond to an integrated luminosity of 138 fb$^{-1}$. No signal is observed. Upper limits on the product of the cross section and branching fractions are derived for narrow resonances A and H with masses up to 2100 and 2000 GeV, respectively, assuming A boson production through gluon fusion. The results are also interpreted within two-Higgs-doublet models, where A and H are CP-odd and CP-even states, respectively, complementing and substantially extending the reach of previous searches.

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CMS Collaboration. 2024-11-30. Search for heavy neutral Higgs bosons A and H in the $\mathrm{t\bar{t}}$Z channel in proton-proton collisions at 13 TeV. https://doi.org/10.1016/j.physletb.2025.139568

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