Hierarchical Neutrino Masses and Large Mixing Angles from the Fritzsch Texture of Lepton Mass Matrices

We show that the Fritzsch texture of lepton mass matrices can naturally lead to the bi-large flavor mixing pattern, if three neutrinos have a normal but weak mass hierarchy (typically, $m_1 : m_2 : m_3 \sim 1 : 3 :10$). The effective mass of the tritium beta decay and that of the neutrinoless double beta decay are too small to be observable in this ansatz, but CP violation at the percent level is allowed and could be measured in long-baseline neutrino oscillations.Comment: LaTex 15 pages (5 PS figures). More discussions adde

Neutrino Mixing and CP Violation in Matter

Within the framework of three lepton families I present a transparent analytical relationship between the neutrino mixing and CP-violating parameters in vacuum and thos in matter. Such a model- and parametrization-independent result will be particularly useful to recast the fundamental lepton flavor mixing matrix from the future long-baseline neutrino experiments.Comment: Talk given at the 3rd International Symposium on Symmetries in Subatomic Physics, Adelaide, Australia, March 13 - 17, 2000; to appear in the proceeding

Texture Zeros and CP-violating Phases in the Neutrino Mass Matrix

We stress that specific texture zeros of lepton mass matrices, which might dynamically arise from a new kind of flavor symmetry, can help us to establish simple and testable relations between the lepton flavor mixing parameters and lepton mass ratios. We present a brief review of one-zero, two-zero and three-zero textures of the neutrino mass matrix. Their phenomenological consequences on neutrino mixing and CP violation are also discussed.Comment: 8 pages. Talk given at NOON2004 conference, February 2004, Toky

Commutators of Lepton Mass Matrices, CP Violation, and Matter Effects in Medium-Baseline Neutrino Experiments

We introduce the commutators of lepton mass matrices to describe the phenomenon of lepton flavor mixing, and establish their relations to the effective Hamiltonians responsible for the propagation of Dirac and Majorana neutrinos. The determinants of those commutators are invariant under matter effects, leading to an instructive relationship between the universal CP-violating parameters in vacuum and in matter. In the scenario of low-energy (100 MeV \leq E \leq 1 GeV) and medium-baseline (100 km \leq L \leq 400 km) neutrino experiments, we illustrate the features of lepton flavor mixing and CP violation. The terrestrial matter effects on CP- and T-violating asymmetries in \nu_\mu \to \nu_e and $\bar{\nu}_\mu \to \bar{\nu}_e neutrino oscillations are also discussed. We demonstrate that a relatively pure signal of leptonic CP violation at the percent level can be established from such medium-baseline experiments with low-energy neutrino beams.Comment: RevTex 19 pages. Some changes. Phys. Rev. D (in printing