Residual Z(2) X Z(2) symmetries and lepton mixing

Author(s)
L. Lavoura, P. O. Ludl
Abstract

We consider two novel scenarios of residual symmetries of the lepton mass matrices. Firstly we assume a Z(2) X Z(2) symmetry G(l) for the charged-lepton mass matrix and a Z(2) symmetry G(v) for the light neutrino mass matrix. With this setting, the moduli of the elements of one column of the lepton mixing matrix are fixed up to a reordering. One may interchange the roles of G(l) and G(v) in this scenario, thereby constraining a row, instead of a column, of the mixing matrix. Secondly we assume a residual symmetry group G(l congruent to) Zm (m>2) which is generated by a matrix with a doubly-degenerate eigenvalue. Then, with G congruent to Z(2) X Z(2) the moduli of the elements of a row of the lepton mixing matrix get fixed. Using the library of small groups we have performed a search for groups which may embed G(l) and G(v) in each of these two scenarios. We have found only two phenomenologically viable possibilities, one of them constraining a column and the other one a row of the mixing matrix.

Organisation(s)
Particle Physics
External organisation(s)
Universidade Técnica de Lisboa
Journal
Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics
Volume
731
Pages
331-336
No. of pages
6
ISSN
0370-2693
DOI
https://doi.org/10.1016/j.physletb.2014.03.001
Publication date
04-2014
Peer reviewed
Yes
Austrian Fields of Science 2012
103034 Particle physics, 103036 Theoretical physics
Portal url
https://ucris.univie.ac.at/portal/en/publications/residual-z2-x-z2-symmetries-and-lepton-mixing(7429f3f5-456a-43ba-98b8-94f978853052).html