Zhi-zhong Xing

Mass and flavor mixing schemes of quarks and leptons

Abstract We give an overview of recent progress in the study of fermion mass and flavor mixing phenomena. The hints exhibited by the quark and lepton mass spectra towards possible underlying flavor symmetries, from which realistic models of mass generation could be built, are emphasized. A variety of schemes of quark mass matrices at low and superhigh energy scales are described, and their consequences on flavor mixing and CP violation are discussed. Instructive patterns of lepton mass matrices, which can naturally lead to large flavor mixing angles, are explored to interpret current data on atmospheric and solar neutrino oscillations. We expect that B-meson factories and long-baseline neutrino experiments will soon shed more light on the dynamics of fermion masses, flavor mixing and CP violation.

Maximal neutrino mixing and maximal CP violation

We propose a phenomenological model of lepton mixing and CP violation based on the flavor democracy of charge leptons and the mass degeneracy of neutrinos. A nearly bi-maximal flavor mixing pattern, which is favored by current data on atmospheric and solar neutrino oscillations, emerges naturally from this model after explicit symmetry breaking. The rephasing-invariant strength of CP or T violation can be as large as one percent, leading to significant probability asymmetries between nu_mu to nu_e and bar{nu}_mu to bar{nu}_e (or nu_e to nu_mu) transitions in the long-baseline neutrino experiments.

Wolfenstein parametrization reexamined.

The Wolfenstein parametrization of the 3ifmmodetimeselsetexttimesfi{}3 Kobayashi-Maskawa (KM) matrix V is modified by keeping its unitarity up to an accuracy of O(

Democratic neutrino mixing and radiative corrections

{ensuremath{lambda}}^{6}

CP violation in B d → D + D − , D * + D − , D + D * − , and D * + D * − decays

). This modification can self-consistently lead to the off-diagonal asymmetry of V, ensuremath{Vert}

Bounds on sin2β and |Vub/Vcb| from the light-quark triangle

{mathit{V}}_{mathit{i}mathit{j}}

Bimaximal neutrino mixing pattern reexamined

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Commutators of lepton mass matrices, CP violation, and matter effects in medium-baseline neutrino experiments

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Test of CPT symmetry in CP-violating B decays.

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