COLD DARK MATTER AND HIGGS MASS IN THE CONSTRAINED MINIMAL SUPERSYMMETRIC STANDARD MODEL WITH GENERALIZED YUKAWA QUASI-UNIFICATION

Abstract

The construction of specific supersymmetric grand unified models based on the Pati–Salam gauge group and leading to a set of Yukawa quasi-unification conditions which can allow an acceptable b-quark mass within the constrained minimal supersymmetric standard model with μ > 0 is briefly reviewed. Imposing constraints from the cold dark matter abundance in the universe, B physics, and the mass mhof the lighter neutral CP-even Higgs boson, we find that there is an allowed parameter space with, approximately, 44 ≤ tan β ≤ 52, -3 ≤ A0/M1/2≤ 0.1, 122 ≤ mh/ GeV ≤ 127, and mass of the lightest sparticle in the range (0.75–1.43) TeV. Such heavy lightest sparticle masses can become consistent with the cold dark matter requirements on the lightest sparticle relic density thanks to neutralino–stau coannihilations which are enhanced due to stau–antistau coannihilation to down type fermions via a direct-channel exchange of the heavier neutral CP-even Higgs boson. Restrictions on the model parameters by the muon anomalous magnetic moment are also discussed.