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Operator identification in charged lepton-flavor violation: Global EFT analysis with RG evolution, polarization observables, and Bayesian model discrimination at future colliders

Nicolas Viaux M.

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Phys. Rev. D 113, 096003 – Published 6 May, 2026

DOI: https://doi.org/10.1103/9nlb-zzf1

Abstract

Charged lepton-flavor violation is a null-test frontier of the Standard Model and a direct probe of physics beyond it. We present a global effective field theory (EFT) analysis across FCC-ee, ILC, CLIC, HL-LHC, HE-LHC, and muon colliders at 3 and 10 TeV, with operator identification as the primary target rather than exclusion reach alone. The analysis combines low-energy constraints, collider differential observables, and Dalitz-level μ→3e information in a common profile-likelihood framework. Key hadron-collider and muon-collider signal/background samples are generated at the event level and propagated through Delphes detector simulation, while clean e+e− benchmark channels are modeled with a parametric response calibrated to published detector-performance benchmarks. We include one-loop renormalization group (RG) running and operator mixing between UV matching and measurement scales, finding 10–30% shifts in selected operator-correlation entries when comparing tree-level and RG-evolved coefficient mappings at multi-TeV matching scales. Polarization asymmetries are used to separate cHℓ and cHe directions, and UV discrimination is quantified with Bayes factors for benchmark leptoquark and heavy-neutral-lepton hypotheses. The full code chain for event generation, detector response, inference, and figure reproduction is provided.

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Phys. Rev. D 113, 096003– Published 6 May, 2026
  • Received 14 February 2026
  • Accepted 13 April 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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