Vacuum stability in a minimal s(3) extension of the standard model

Abstract

This work deals with the gauge symmetry breaking and the vacuum stability conditions in a minimal S-3-invariant extension of the Standard Model. In the theory, there are three SU(2)(L) Higgs doublets that belong to the singlet and doublet representations of the S-3-flavor group. We find that, as function of the vacuum expectation values of the twelve real Higgs fields, the Higgs potential has three types of minimum: a normal minimum, an electric Charge breaking (CB) minimum and a CP violating minimum (CPB) depending on the vacuum expectation values (vev) of the Higgs fields H-1, H-2 and H-S. Assuming that the non-vanishing vev of the Higgs doublet in the singlet representation of S-3 is real, we obtain that the deepest minimum is the normal minimum. This condition corresponds to the Pak-vasa-Sugawara minimum in which we obtain an S-2 residual symmetry. This feature simplifies the structure and therefore the Computation of the Higgs mass matrices. We present some results on the mass spectrum of the Higgs bosons in the theory.