Yukawa quasi-unification

We construct concrete supersymmetric grand unified theories based on the Pati–Salam gauge group SU(4)c×SU(2)L×SU(2)R which naturally lead to a moderate violation of ‘asymptotic’ Yukawa unification and thus can allow an acceptable b-quark mass even with universal boundary conditions. We consider the constrained minimal supersymmetric standard model which emerges from one of these theories with a deviation from Yukawa unification which is adequate for μ>0. We show that this model possesses a wide and natural range of parameters which is consistent with the data on b→sγ, the muon anomalous magnetic moment, the cold dark matter abundance in the universe, and the Higgs boson masses. The lightest supersymmetric particle can be as light as about 107 GeV.