Lepton flavor violation in Higgs boson decays at the HL-LHC

A bstract We explore the discovery potential for lepton flavor-violating Higgs boson decays, h → ℓ i ℓ j ( ℓ i ≠ ℓ j ; ℓ = e, μ, τ ), in proton-proton collisions. The analysis is performed within a Froggatt-Nielsen framework, which offers a well-motivated theoretical mechanism for such processes. By performing a systematic scan over the phenomenologically viable parameter space, we identify regions that can yield observable signatures at the High-Luminosity LHC (HL-LHC). For an integrated luminosity of ℒ int ≳ 1000 fb − 1 , we project that the channels h → eμ and h → τμ (with τ ± → π ± ν τ ) could reach the 5 σ discovery threshold, while h → τe remains inaccessible even at 3000 fb − 1 . Our results highlight the unique capability of the HL-LHC to probe new physics through searches for rare Higgs decays.