Neutrino Oscillations Induced by Two-loop Radiative Mechanism

Abstract

Two-loop radiative mechanism, when combined with an U(1)_{L'} symmetry generated by L_e-L_\mu-L_\tau (=L'), is shown to provide an estimate of \Delta m^2_{\odot}/\Delta m^2_{atm} $\sim$ \epsilon m_e/m_\tau, where \epsilon measures the U(1)_{L'}-breaking. Since \Delta m^2_{atm} $\sim 3.5x10^{-3}e{V}^2,wefindthat\Delta m_{\odot }^2$\sim$ϵx10^{-6}e{V}^2,whichwillfallintotheallowedregionoftheLOWsolutiontothesolarneutrinoproblemforϵ$\sim$ 0.1.

Comments: ReVTeX, 6 pages. Appendix added, one reference added and typographical errors corrected. Version to appear in Phys. Lett. B