A Novel Parametrization of tau-lepton Dominance and Simplified One-loop Renormalization-group Equations of Neutrino Mixing Angles and CP-violating Phases

摘要

We point out that the $\tau$-lepton dominance in the one-looprenormalization-group (RG) equations of neutrino mixing quantities allows us toset a criterion to choose the most suitable parametrization of the leptonflavor mixing matrix $U$: its elements $U^{}_{3i}$ (for $i=1,2,3$) should be assimple as possible. Such a novel parametrization is quite different from the"standard" one used in the literature and can lead to greatly simplified RGequations for three mixing angles and the physical CP-violating phase(s) in thestandard model or its minimal supersymmetric extension, no matter whetherneutrinos are Dirac or Majorana particles. Some important features of ouranalytical results and their phenomenological consequences are also discussed.