1. Search for a new Z′ gauge boson in 4μ events with the ATLAS experiment.
- Author
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Aad, G., Abbott, B., Abbott, D. C., Abeling, K., Abidi, S. H., Aboulhorma, A., Abramowicz, H., Abreu, H., Abulaiti, Y., Abusleme Hoffman, A. C., Acharya, B. S., Achkar, B., Adam Bourdarios, C., Adamczyk, L., Adamek, L., Addepalli, S. V., Adelman, J., Adiguzel, A., Adorni, S., and Adye, T.
- Subjects
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GAUGE bosons , *PROTON-proton interactions , *STANDARD model (Nuclear physics) , *LARGE Hadron Collider , *Z bosons , *CONFIDENCE intervals , *HADRON-hadron scattering - Abstract
This paper presents a search for a new Z′ vector gauge boson with the ATLAS experiment at the Large Hadron Collider using pp collision data collected at s = 13 TeV, corresponding to an integrated luminosity of 139 fb−1. The new gauge boson Z′ is predicted by Lμ − Lτ models to address observed phenomena that can not be explained by the Standard Model. The search examines the four-muon (4μ) final state, using a deep learning neural network classifier to separate the Z′ signal from the Standard Model background events. The di-muon invariant masses in the 4μ events are used to extract the Z′ resonance signature. No significant excess of events is observed over the predicted background. Upper limits at a 95% confidence level on the Z′ production cross-section times the decay branching fraction of pp → Z′μμ → 4μ are set from 0.31 to 4.3 fb for the Z′ mass ranging from 5 to 81 GeV. The corresponding common coupling strengths, gZ′, of the Z′ boson to the second and third generation leptons above 0.003 – 0.2 have been excluded. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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