Liu, C (reprint author), Chinese Acad Sci, Inst Theoret Phys, POB 2735, Beijing 100190, Peoples R China.
[Liu, Chun] Chinese Acad Sci, Inst Theoret Phys, Beijing 100190, Peoples R China
A natural model of realizing effective supersymmetry is presented. Two sets of the Standard Model-like gauge group G(1) x G(2) are introduced, where G(i) = SU(3)(i) x SU(2)(i) x U(1)(i), which break diagonally to the Standard Model gauge group at the energy scale M similar to 107 GeV. Gauge couplings in G(1) are assumed to be much larger than those in G(2). Gauge-mediated supersymmetry breaking is adopted. The first two generations (third generation) are only charged only under G(1) (G(2)). The effective supersymmetry spectrum is obtained. The reproduction of realistic Yukawa couplings is studied. The fine-tuning for a 126 GeV Higgs is reduced by the large A term due to direct Higgs-messenger interaction. Finally, G(2) is found to be a nontrivial realization of the strong unification scenario in which case we can predict alpha(s)(M-Z) without real unification.