Four-lepton Z-boson decay constraints on the SMEFT

Abstract

We discuss how four-lepton decays of the Z-boson probe currently unconstrained flat directions in the parameter space of the Standard Model Effective Field Theory (SMEFT). We derive the constraints from these decays on four-lepton operators in the SMEFT and show how the LHC data for this process complements probes from neutrino-trident production. Future differential measurements with high-luminosity data can strongly constrain four-lepton operators and remove all flat directions in the four-muon sector of the SMEFT. We comment briefly on the possibility of using rare Z-decays to tau-leptons to probe untested directions in the SMEFT parameter space.

arXiv comment17 pages, 4 figures

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Cited by in corpus (6)

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• Disentangling SMEFT operators with future low-energy PVES experiments
• Lepton flavor violation by two units
• Constraining dimension-6 SMEFT with higher-order predictions for $pp\to tW$
• Search for the Z boson decay to $\tau \tau \mu \mu$ in proton-proton collisions at $\sqrt{s}$ = 13 TeV
• Dilepton production in the SMEFT at $\mathcal{O}(1/{\Lambda }^4)$