A three-parameter model for the neutrino mass matrix

Autor(en)

Walter Grimus, Luis Lavoura

Abstrakt

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(en)

Teilchenphysik

Externe Organisation(en)

Universidade Técnica de Lisboa

Journal

Journal of Physics G: Nuclear and Particle Physics

Band

34

Seiten

1757-1769

Anzahl der Seiten

13

ISSN

0954-3899

DOI

https://doi.org/10.1088/0954-3899/34/7/014

Publikationsdatum

2007

Peer-reviewed

Ja

ÖFOS 2012

103036 Theoretische Physik

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/a-threeparameter-model-for-the-neutrino-mass-matrix(9be06a22-59e2-48bd-a4a0-07ddc3ea7f64).html