Leptonic invariants, neutrino mass-ordering and the octant of θ23

  • G. C. Branco
  • M. N. RebeloEmail author
  • J. I. Silva-Marcos
Open Access
Regular Article - Theoretical Physics


We point out that leptonic weak-basis invariants are an important tool for the study of the properties of lepton flavour models. In particular, we show that appropriately chosen invariants can give a clear indication of whether a particular lepton flavour model favours normal or inverted hierarchy for neutrino masses and what is the octant of θ23. These invariants can be evaluated in any conveniently chosen weak-basis and can also be expressed in terms of neutrino masses, charged lepton masses, mixing angles and CP violation phases.


Beyond Standard Model Neutrino Physics 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


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Copyright information

© The Author(s) 2017

Authors and Affiliations

  • G. C. Branco
    • 1
    • 2
  • M. N. Rebelo
    • 1
    • 2
    Email author
  • J. I. Silva-Marcos
    • 1
  1. 1.Departamento de Física and Centro de Física Teórica de Partículas (CFTP), Instituto Superior Técnico (IST)Universidade de Lisboa (UL)LisboaPortugal
  2. 2.Theory DepartmentCERNGeneva 23Switzerland

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