Flavor Violation in a Minimal SO(10)\times A_4 SUSY GUT

Abstract

Flavor violating processes in the quark and lepton sectors are investigated within a realistic supersymmetric $SO(10)\times A_4$ grand unification model. By employing exotic heavy fermion fields, this model successfully describes various features of the fermion masses and mixings including large neutrino mixings accompanied by small quark mixings. In this model the flavor violation is induced at GUT scale, at which $A_4$ flavor symmetry is broken, as a consequence of the large mixings of the light fermion fields with these exotic heavy fields. The stringent experimental constraint from $\mu \to e\gamma$ decay rate necessitates a high degree of degeneracy of the supersymmetry breaking soft scalar masses of the exotic heavy fields and supersymmetric scalar partners of the light fermion fields. The choice of slepton masses of order 1 TeV is found to be consistent with the constraints from branching ratio of $\mu \to e\gamma$ and with all other flavor changing neutral current processes being sufficiently suppressed.

Comments: 31 pages, 2 figures; International Journal of Modern Physics A, Vol.27 (2012)