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

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

Towards Isolation of New Physics in B^0_s-\bar{B}^0_s Mixing

In many extensions of the standard model, new physics is possible to contribute significantly to B^0_s-\bar{B}^0_s mixing. We show that the effect of new physics, both its phase information and its magnitude, can be isolated from measurements of CP asymmetries in the semileptonic B_s transitions and in some nonleptonic B_s decays into hadronic CP eigenstates. We also find that the rates of CP-forbidden decays at the \Upsilon (5S) resonance are not suppressed by the large B_s mass difference, thus they can be used to extract the CP-violating phase of new physics in either B^0_s-\bar{B}^0_s or K^0-\bar{K}^0 mixing.Comment: Big Latex 11 page