Hierarchical four-neutrino oscillations with a decay option

Abstract

We present a new and novel synthesis of all existing neutrino data regarding the disappearance and appearance of ν_e and ν_μ. We assume four neutrinos: ν_e,ν_μ,ν_τ, as well as a heavier singlet neutrino ν_s of a few eV. The latter may decay into a massless Goldstone boson (the singlet Majoron) and a linear combination of the doublet antineutrinos. We comment on how this scenario may be verified or falsified in future experiments. We point out how it allows us to evade the CDHSW constraints.