Probing a heavy neutral lepton in a radiative neutrino model at a muon collider
Abstract
We investigate direct and Higgs-mediated production of a Dirac heavy neutral lepton in a radiative neutrino-mass model at a future 3 TeV muon collider. We consider heavy neutral lepton masses in the window mZ<mN<mh, where the decays N→ℓ W and N→νZ can proceed with on-shell weak bosons. We consider both direct production, μ+μ-→ Nν, and Higgs-mediated production through μ+μ-→νμν̅μh, h→ Nν. Both channels lead to the common ℓ± jj+pTmiss final state. We perform a detector-level analysis with an integrated luminosity of 1 ab−1, assuming unpolarized muon beams, and derive median expected 95% confidence-level upper limits on the visible signal cross section ranging from approximately $0.027$ to 0.113 fb, corresponding to limits on the mixing strength parameter |UμN|2 ranging from 6.7×10−6 to 8.3×10−5 for six benchmark points. The Higgs-mediated production channel contributes ∼15--72% of the signal after the common event selection, but improves the expected limits by ∼0.18--1.19% within the common classifier and binning scheme. This small improvement reflects the classifier-score distribution of the Higgs-mediated events. The limits on |UμN|2 account for the benchmark-specific flavor mixings and assume an independent 10% background uncertainty in each classifier-score bin.
Related
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BibTeX
@misc{bamwidhi2026probing,
title = {{Probing a heavy neutral lepton in a radiative neutrino model at a muon collider}},
author = {Isaac Bamwidhi and Mohamed Belfkir and Mohamed Amin Loualidi and Salah Nasri},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.28252},
eprint = {2610.28252},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.28252},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Probing a heavy neutral lepton in a radiative neutrino model at a muon collider
AU - Isaac Bamwidhi
AU - Mohamed Belfkir
AU - Mohamed Amin Loualidi
AU - Salah Nasri
PY - 2026
DA - 2026/10/20
PB - arXiv
DO - 10.48550/arxiv.2610.28252
UR - https://arxiv.org/abs/2610.28252
AB - We investigate direct and Higgs-mediated production of a Dirac heavy neutral lepton in a radiative neutrino-mass model at a future 3 TeV muon collider. We consider heavy neutral lepton masses in the window m_Z<m_N<m_h, where the decays N→ℓ W and N→νZ can proceed with on-shell weak bosons. We consider both direct production, μ^+μ^-→ Nν, and Higgs-mediated production through μ^+μ^-→ν_μν̅_μh, h→ Nν. Both channels lead to the common ℓ^± jj+p_T^miss final state. We perform a detector-level analysis with an integrated luminosity of 1 ab^−1, assuming unpolarized muon beams, and derive median expected 95% confidence-level upper limits on the visible signal cross section ranging from approximately $0.027$ to 0.113 fb, corresponding to limits on the mixing strength parameter |U_μN|^2 ranging from 6.7×10^−6 to 8.3×10^−5 for six benchmark points. The Higgs-mediated production channel contributes ∼15--72% of the signal after the common event selection, but improves the expected limits by ∼0.18--1.19% within the common classifier and binning scheme. This small improvement reflects the classifier-score distribution of the Higgs-mediated events. The limits on |U_μN|^2 account for the benchmark-specific flavor mixings and assume an independent 10% background uncertainty in each classifier-score bin.
ER -