Atmospheric Neutrino Oscillation and a Phenomenological Lepton Mass Matrix

Abstract

We propose simple phenomenological lepton mass matrices which describe the three neutrinos almost degenerate in mass, leading to a very large mixing angle between ${\nu }_{\mu }$ and ${\nu }_{\tau }$, as consistent with a recent report on atmospheric neutrino oscillation from the Superkamiokande collaboration. Our matrix model also gives ${\nu }_e-{\nu }_{\mu }$ mixing in agreement with the value required for neutrino oscillation to explain the solar neutrino problem.

Comments: 10 pages, Latex file, small corrections in text and references, to appear in PRD