Orateur
Description
Lepton number violation (LNV) is a key signal of physics beyond the Standard Model, often linked to neutrino mass generation and baryogenesis. In this talk, I will present our study of dimension-seven $\Delta L = 2$ SMEFT operators at a same-sign muon collider, focusing on the process $\mu^+\mu^+ → W^+W^+ / W^+qq'$ at $\sqrt{s} = 2$ TeV with 1 ab$^{-1}$ luminosity, inspired by the $\mu$TRISTAN proposal. We analyze final states with two fat jets, targeting hadronic W decays to probe eight distinct LNV operators. The clean environment and unique initial state make this channel highly sensitive, with minimal Standard Model background. We estimate the collider’s reach for each operator and compare it with current LHC bounds and future FCC projections. Our results show that same-sign muon colliders offer a powerful and complementary probe of TeV-scale LNV, and can significantly advance our understanding of new physics beyond the Standard Model.
