The minimal adjoint-SU(5)xZ_4 GUT model

Understand

An extension of the adjoint SU(5) model with a flavour symmetry based on the Z_4 group is investigated.

• The Z_4 symmetry is introduced with the aim of leading the up- and down-quark mass matrices to the Nearest-Neighbour-Interaction form.
• As a consequence of the discrete symmetry embedded in the SU(5) gauge group, the charged lepton mass matrix also gets the same form.
• Within this model, light neutrinos get their masses through type-I, type-III and one-loop radiative seesaw mechanisms, implemented, respectively, via a singlet, a triplet and an octet from the adjoint fermionic 24 fields.