Searching for Lepton Flavor Violating decays of the Higgs Boson into μτ, eτ, and eμ final states at FCC-ee
Abstract
We investigate the projected sensitivity of the FCC-ee in probing the LFV decay of the 125 GeV Higgs boson, h→μτ, h→ eτ, and h → eμ at center-of-mass energy of 240 GeV with an integrated luminosity of 5 ab−1. With the clean multi-lepton final states, we consider the Higgs production modes that contribute to e+e- → ℓℓ h, in particular, the Higgs-strahlung and the vector boson fusion production channels. The 95\% CL upper limits on branching ratio are found to be 5.94 × 10−4, 6.28 × 10−4, and 7.37 × 10−5 for the channels h→μτ, h→ eτ, and h → eμ, respectively. In addition, we also consider the LFV decay of a new CP-even Higgs boson with mass in the range of 110−200 GeV. The projected FCC-ee sensitivities are then compared to those from low energy searches for ℓ→ℓ'γ decay. We find that the FCC-ee sensitivity for the LFV decays of the Higgs in the e−τ and μ−τ channels is superior to the low-energy constraints. However, in the e−μ case, the low energy search offers stronger constraints.
Versions
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BibTeX
@misc{sriling2026searching,
title = {{Searching for Lepton Flavor Violating decays of the Higgs Boson into $μτ$, $eτ$, and $eμ$ final states at FCC-ee}},
author = {P. Sriling and N. Srimanobhas and P. Uttayarat and R. Uttho and V. Wachirapusitanand},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2605.30971},
eprint = {2605.30971},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2605.30971},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Searching for Lepton Flavor Violating decays of the Higgs Boson into μτ, eτ, and eμ final states at FCC-ee
AU - P. Sriling
AU - N. Srimanobhas
AU - P. Uttayarat
AU - R. Uttho
AU - V. Wachirapusitanand
PY - 2026
DA - 2026/09/29
PB - arXiv
DO - 10.48550/arxiv.2605.30971
UR - https://arxiv.org/abs/2605.30971
AB - We investigate the projected sensitivity of the FCC-ee in probing the LFV decay of the 125 GeV Higgs boson, h→μτ, h→ eτ, and h → eμ at center-of-mass energy of 240 GeV with an integrated luminosity of 5 ab^−1. With the clean multi-lepton final states, we consider the Higgs production modes that contribute to e^+e^- → ℓℓ h, in particular, the Higgs-strahlung and the vector boson fusion production channels. The 95\% CL upper limits on branching ratio are found to be 5.94 × 10^−4, 6.28 × 10^−4, and 7.37 × 10^−5 for the channels h→μτ, h→ eτ, and h → eμ, respectively. In addition, we also consider the LFV decay of a new CP-even Higgs boson with mass in the range of 110−200 GeV. The projected FCC-ee sensitivities are then compared to those from low energy searches for ℓ→ℓ'γ decay. We find that the FCC-ee sensitivity for the LFV decays of the Higgs in the e−τ and μ−τ channels is superior to the low-energy constraints. However, in the e−μ case, the low energy search offers stronger constraints.
ER -