Common Hierarchical Lepton Mass Textures for Atmospheric and Solar Neutrino Oscillations

We propose and study a common hierarchical mass texture for both charged lepton and neutrino sectors. The texture gives rise to a large $\nu_\mu\leftrightarrow\nu_\tau$ mixing. Also it leads to the small angle MSW effect solution for solar neutrino data. It naturally gives a small $\nu_e\leftrightarrow \nu_\tau$ oscillation relevant to the CHOOZ result in certain mass limits.