Verifiable model of neutrino masses from large extra dimensions

Abstract

We propose a new scenario of neutrino masses with a Higgs triplet (ξ⁺⁺,ξ⁺,ξ ⁰) in a theory of large extra dimensions. Lepton number violation in a distant brane acts as the source of a very small trilinear coupling of ξ to the standard Higgs doublet in our brane. Small realistic Majorana neutrino masses are naturally obtained with the fundamental scale M_∗ ~O(1) TeV, foretelling the possible discovery of ξ (m_ξ≲M_∗) at future colliders. Decays of ξ⁺⁺ into same-sign dileptons are fixed by the neutrino mass matrix. Observation of μ-e conversion in nuclei is predicted.