CMSSM With Generalized Yukawa Quasi-Unification: An Update

TL;DR

This paper updates the analysis of the CMSSM with generalized Yukawa quasi-unification, identifying two viable parameter regions consistent with dark matter, collider, and Higgs constraints, and exploring their phenomenological implications.

Contribution

It introduces a generalized Yukawa quasi-unification condition in the CMSSM and maps out the parameter space compatible with current experimental constraints.

Findings

Two distinct allowed regions in parameter space identified.

Heavy lightest sparticle masses compatible with dark matter relic density.

Potential detectability of the lightest sparticle in current dark matter experiments.

Abstract

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.