Abstract
A search for the Higgs boson decaying into a photon and a pair of electrons or muons with an invariant mass mℓℓ < 30$ GeV is presented. The analysis is performed using 139 fb-1 of proton-proton collision data, produced by the LHC at a centre-of-mass energy of 13 TeV and collected by the ATLAS experiment. Evidence for the H → ℓℓγ process is found with a significance of 3.2 over the background-only hypothesis, compared to an expected significance of 2.1 for the Standard Model prediction. The best-fit value of the signal strength parameter, defined as the ratio of the observed signal yield to the one expected in the Standard Model, is μ = 1.5 ± 0.5. The Higgs boson production cross-section times the H → ℓℓγ branching ratio for mℓℓ < 30$ GeV is determined to be 8.7-2.7+2.8 fb.
Original language | English |
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Article number | 136412 |
Number of pages | 22 |
Journal | Physics Letters B |
Volume | 819 |
Early online date | 31 May 2021 |
DOIs | |
Publication status | Published - 10 Aug 2021 |
Bibliographical note
Publisher Copyright:© 2021 The Author
Keywords
- hep-ex