Lepton electric and magnetic dipole moments induced by a vector unparticle

Abstract

We calculate the magnetic dipole moment (MDM) and the electric dipole moment (EDM) of a lepton induced by a vector unparticle with both vector and axial-vector couplings to leptons. We consider the most general scenario in which the unparticle induces lepton flavor violation (LFV) and CP violation. Some specific scenarios are examined to obtain constraints on the LFV unparticle couplings from the current limits on the muon MDM and the decay τ → 3μ. While the experimental limit on the muon MDM favor the scenario in which there is dominance of the unparticle vector couplings over the axial-vector couplings, the experimental limit on the τ → 3μ decay strongly constraints the unparticle LFV couplings. We use these constraints to estimate the EDMs of the electron and the muon, which are negligible and far from the current experimental limits.