From Higgs physics to lepton flavour violation: current bounds and future prospects for vector-like lepton models

2026/03/31 by Gregor Daberstiel, Kilian Möhling, Dominik Stöckinger +1
Computer Science · Physics and Astronomy · #Computational Physics and Python Applications #Flavour #Higgs boson #Large Hadron Collider #Lepton #Muon #Neutrino Physics Research #Observable #Particle physics theoretical and experimental studies #Phenomenology (philosophy) #Physics beyond the Standard Model #hep-ph

paper · pdf · doi:10.1007/jhep07(2026)259

published as JHEP 07 (2026) 259 · 42 pages, 51 figures, published version

openalex publication_date 2026/07/28 · openalex created_date 2026/07/31 · arxiv created 2026/08/03 · arxiv updated 2026/08/05 · openalex updated_date 2026/08/05

Abstract

A bstract We present a comprehensive phenomenological study of a class of six vector-like lepton models with seesaw-like mass contributions and strong modifications to Higgs and lepton phenomenology. We focus on lepton flavour conserving and violating observables across all lepton generations and collider observables like Z and Higgs decays. In light of the recent progress at the LHC and precision measurements such as muon g – 2, as well as in anticipation of upcoming experiments like MEGII, Mu2e/COMET, Mu3e, Belle II and at the HL-LHC, we systematically survey the viable parameter space and identify patterns and correlations. The considered class of models gives rise to a rich and testable phenomenology with robust and complementary probes that allow to distinguish between models in the coming experimental era.

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