Large neutrino magnetic moments in supersymmetry in light of the new data

Abstract

We re-analyze the magnetic moments of Dirac and Majorana neutrinos in a supersymmetric extension of the MSSM with singlet right-handed neutrinos. We show that if one incorporates left–right slepton mixing, the neutrino magnetic moment becomes proportional to the corresponding lepton, rather than the neutrino, mass. Incorporating the new SuperKamiokande, the solar and the LSND data, the magnetic moments are larger than previous calculations indicate, and proportional to the tau mass, without invoking any additional symmetries or introducing any exotic particles. The supersymmetric contribution to the magnetic moments of either Dirac or Majorana neutrinos can become of order O(10 −12)μ B and therefore of interest experimentally.