CCAST, World Lab, Beijing 100080, Peoples R China
; Inst High Energy Phys, Beijing 100049, Peoples R China
; Univ Munich, Sekt Phys, D-80333 Munich, Germany
We speculate that the mass spectrum of three neutrinos might have a normal hierarchy as that of three charged leptons or that of three up-type (or down-type) quarks. In this spirit, we propose a novel parametrization of the 3 x 3 lepton flavor mixing matrix. Its mixing angles theta(l) and theta(v) can be related to the mass ratios m(e)/m(mu) and m(1)/m(2) in a specific texture of lepton mass matrices with vanishing (1, 1) elements: tan theta(l) = root m(e)/m(mu) and tan theta(v) root m(1)/m(2). The latter relation, together with solar and atmospheric neutrino oscillation data, predicts 0.0030 less than or similar to m(1) less than or similar to 0.0073 eV, 0.009 eV less than or similar to m(2) less than or similar to 0.012 eV and 0.042 eV less than or similar to m(3) less than or similar to 0.058 eV. The smallest neutrino mixing angle is found to be theta(13) approximate to theta(l)/root 2 approximate to 3 degrees, which is experimentally accessible in the near future. (c) 2006 Elsevier B.V. All rights reserved.