https://doi.org/10.1140/epjc/s10052-012-1941-1
Regular Article - Theoretical Physics
Neutrino masses in SU(5)×U(1) F with adjoint flavons
1
Laboratori Nazionali di Frascati, INFN, C.P. 13, I00044, Frascati, Italy
2
IFT-UAM/CSIC, Nicolas Cabrera 15, C.U. Cantoblanco, 28049, Madrid, Spain
3
Departamento de Física Teórica, Universidad Autónoma de Madrid, C.U. Cantoblanco, 28049, Madrid, Spain
4
Instituto de Física, Universidad de Antioquia, A.A. 1226, Medellín, Colombia
* e-mail: restrepo@gfif.udea.edu.co
Received:
9
August
2011
Revised:
16
February
2012
Published online:
28
March
2012
We present a SU(5)×U(1) F supersymmetric model for neutrino masses and mixings that implements the seesaw mechanism by means of the heavy SU(2) singlets and triplets states contained in three adjoints of SU(5). We discuss how Abelian U(1) F symmetries can naturally yield non-hierarchical light neutrinos even when the heavy states are strongly hierarchical, and how it can also ensure that R-parity arises as an exact accidental symmetry. By assigning two flavons that break U(1) F to the adjoint representation of SU(5) and assuming universality for all the fundamental couplings, the coefficients of the effective Yukawa and Majorana mass operators become calculable in terms of group theoretical quantities. There is a single free parameter in the model, however, at leading order the structure of the light neutrinos mass matrix is determined in a parameter independent way.
© Springer-Verlag / Società Italiana di Fisica, 2012