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arXiv · 2010.06685

Four-lepton Z-boson decay constraints on the SMEFT

Radja Boughezal·Chien-Yi Chen·Frank Petriello·Daniel Wiegand
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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.

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Radja Boughezal, Chien-Yi Chen, Frank Petriello, Daniel Wiegand. 2020-10-13. Four-lepton Z-boson decay constraints on the SMEFT. https://doi.org/10.1103/physrevd.103.055015

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