Cabibbo Haze in Lepton Mixing
Abstract
With the advent of neutrino oscillations, a new theoretical challenge which has emerged is to understand the origin of the observed discrepancies between the flavor patterns of the quark and lepton sectors within the broad context of quark-lepton unification. To address this issue, we first explore the hypothesis that the Cabibbo angle is an expansion parameter for lepton as well as quark mixing. Cabibbo effects are deviations from zero mixing for the quarks but are deviations from unknown mixings for the leptons, such that lepton mixing is veiled by a Cabibbo haze. We present a systematic classification of parametrizations of the lepton mixing matrix based on this approach and catalog the leading order Cabibbo effects. We next explore flavor models in this context in which neutrino masses are degenerate and charged fermion masses are hierarchical in the limit of an exact SO(2) family symmetry. Large lepton mixings emerge upon symmetry breaking, providing concrete examples of our Cabibbo haze approach.
- Publication:
-
APS April Meeting Abstracts
- Pub Date:
- April 2007
- Bibcode:
- 2007APS..APRK11006E