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Lepton number violation at the LHC in radiative neutrino mass models with leptoquarks

K. S. Babu1,*, Rahool Kumar Barman2,†, and Dorival Gonçalves1,‡

  • *Contact author: babu@okstate.edu
  • †Contact author: rahoolbarman@physics.iitm.ac.in
  • ‡Contact author: dorival@okstate.edu
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Phys. Rev. D 114, 055039 – Published 21 September, 2026

DOI: https://doi.org/10.1103/vbbz-98kg

Abstract

We investigate the prospects for observing lepton number violation (LNV) by two units, |ΔL|=2, at the LHC within the leptoquark variant of the Zee Model, where Majorana neutrino masses arise radiatively at one loop. The model features an SU(2)L doublet and singlet leptoquarks, whose interactions produce a distinctive same-sign dilepton plus jets signature, pp→ℓ±ℓ′±+jets. Taking into account current experimental constraints, we identify the dominant production channels for this LNV signal and perform a detailed collider analysis. We find that the HL-LHC can probe leptoquark masses up to mLQ∼1.5  TeV with this process. Observation of this signal would provide a direct test of LNV and would unambiguously establish the Majorana nature of neutrinos.

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Phys. Rev. D 114, 055039– Published 21 September, 2026
  • Received 15 February 2026
  • Accepted 1 September 2026
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