A three-parameter model for the neutrino mass matrix
- Author(s)
- Walter Grimus, Luis Lavoura
- Abstract
Using the type-II seesaw mechanism with three Higgs doublets phi(alpha) (alpha = e, mu, tau) and four Higgs triplets, we build a model for lepton mixing based on a 384-element horizontal symmetry group, generated by the permutation group S-3 and by six Z(2) transformations. The charged- lepton mass matrix is diagonal; the symmetries of the model would require all the three masses ma to be equal, but different vacuum expectation values of fa allow m(alpha) to split. The number of parameters in the Majorana neutrino mass matrix M-v depends on two options: full breaking of the permutation group S-3, or leaving mu-t interchange symmetry intact, and hard or spontaneous violation of CP. We discuss in detail the case with the minimal number of three parameters, wherein M-v is real, symmetric under mu-tau interchange and has equal diagonal elements. In that case, CP is conserved in lepton mixing, atmospheric neutrino mixing is maximal and theta(13) = 0; moreover, the type of neutrino mass spectrum and the absolute neutrino mass scale are sensitive functions of the solar mixing angle.
- Organisation(s)
- Particle Physics
- External organisation(s)
- Universidade Técnica de Lisboa
- Journal
- Journal of Physics G: Nuclear and Particle Physics
- Volume
- 34
- Pages
- 1757-1769
- No. of pages
- 13
- ISSN
- 0954-3899
- DOI
- https://doi.org/10.1088/0954-3899/34/7/014
- Publication date
- 2007
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103036 Theoretical physics
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/a-threeparameter-model-for-the-neutrino-mass-matrix(9be06a22-59e2-48bd-a4a0-07ddc3ea7f64).html