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CMSSM With Generalized Yukawa Quasi-Unification: An Update

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 نشر من قبل C. Pallis
 تاريخ النشر 2015
  مجال البحث فيزياء
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We analyze the parametric space of the constrained minimal supersymmetric standard model (CMSSM) with mu>0 supplemented by a generalized asymptotic Yukawa coupling quasi-unification condition which yields acceptable masses for the fermions of the third family. We impose constraints from the cold dark matter abundance in the universe and its direct detection experiments, the B-physics, as well as the masses of the sparticles and the lightest neutral CP-even Higgs boson, m_h. We identify two distinct allowed regions with M_{1/2}>m_0 and m_0>>M_{1/2} classified in the hyperbolic branch of the radiative electroweak symmetry breaking. In the first region we obtain, approximately, 44<=tan beta<=52, -3<=A_0/M_{1/2}<=0.1, 122<=m_h/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 requirement on the lightest sparticle relic density thanks to neutralino-stau coannihilations. In the latter region, fixing m_h to its central value from the LHC, we find a wider allowed parameter space with milder electroweak-symmetry-breaking fine-tuning, 40<=tanbeta<=50, -11<=A_0/M_{1/2}<=15 and mass of the lightest sparticle in the range (0.09-1.1) TeV. This sparticle is possibly detectable by the present cold dark matter direct search experiments.



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We analyze the parametric space of the constrained minimal supersymmetric standard model with mu>0 supplemented by a generalized asymptotic Yukawa coupling quasi-unification condition which yields acceptable masses for the fermions of the third famil y. We impose constraints from the cold dark matter abundance in the universe and its direct detection experiments, the B-physics, as well as the masses of the sparticles and the lightest neutral CP-even Higgs boson. Fixing the mass of the latter to its central value from the LHC and taking 40<=tanbeta<=50, we find a relatively wide allowed parameter space with -11<=A_0/M_{1/2}<=15 and mass of the lightest sparticle in the range (0.09-1.1) TeV. This sparticle is possibly detectable by the present cold dark matter direct search experiments. The required fine-tuning for the electroweak symmetry breaking is much milder than the one needed in the neutralino-stau coannihilation region of the same model.
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