Lepton Number Violation at the LHC in Radiative Neutrino Mass Models with Leptoquarks

Abstract

We investigate the prospects for observing lepton number violation (LNV) by two units, $|\Delta L|=2$, 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, $pp\to {\ell }^{\pm }{\ell }^{\prime \pm }+\text{jets}$. 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 $m_{\mathrm{LQ}}\sim 1.5\mathrm{TeV}$ with this process. Observation of this signal would provide a direct test of LNV and would unambiguously establish the Majorana nature of neutrinos.

Comments: 19 pages, 7 figures, and 2 tables