Search for a new Z′ gauge boson in 4μ events with the ATLAS experiment

Summary, in English

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. [Figure not available: see fulltext.]. © 2023, The Author(s).

• Author: G. Aad; T.P.A. Åkesson; E.E. Corrigan; C. Doglioni; P.A. Ekman; J. Geisen; V. Hedberg; H. Herde; G. Jarlskog; B. Konya; E. Lytken; J.U. Mjörnmark; G.A. Mullier; R. Poettgen; N.D. Simpson; E. Skorda; O. Smirnova; L. Zwalinski
• Department/s: Particle and nuclear physics; eSSENCE: The e-Science Collaboration
• Publishing year: 2023
• Language: English
• Publication/Series: Journal of High Energy Physics
• Volume: 2023
• Issue: 7
• Links: http://dx.doi.org/10.1007/JHEP07(2023)090
• Document type: Journal article
• Publisher: Springer
• Topic: Subatomic Physics
• Keywords: Beyond Standard Model; Hadron-Hadron Scattering
• Status: Published
• ISBN/ISSN/Other: ISSN: 1029-8479