Abstract
This paper presents a search for decays of the Higgs boson with a mass of 125 GeV into a pair of new pseudoscalar particles, H → aa , where one a-boson decays into a b-quark pair and the other into a muon pair. The search uses 139 fb-1 of proton-proton collision data at a center-of-mass energy of √s = 13 TeV recorded between 2015 and 2018 by the ATLAS experiment at the LHC. A narrow dimuon resonance is searched for in the invariant mass spectrum between 16 GeV and 62 GeV. The largest excess of events above the Standard Model backgrounds is observed at a dimuon invariant mass of 52 GeV and corresponds to a local (global) significance of 3.3σ ( 1.7σ ). Upper limits at 95% confidence level are placed on the branching ratio of the Higgs boson to the bbμμ final state, B(H → aa → bbμμ), and are in the range 0.2–4.0 × 10−4, depending on the signal mass hypothesis.
Original language | English |
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Article number | 012006 |
Number of pages | 29 |
Journal | Physical Review D - Particles, Fields, Gravitation and Cosmology |
Volume | 105 |
Issue number | 1 |
DOIs | |
Publication status | Published - 1 Jan 2022 |
Bibliographical note
44 pages in total, author list starting page 28, 12 figures, 3 tables, published in PRD. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HDBS-2021-03/Keywords
- hep-ex