Realistic MSSM From Minimal Yukawa Deflection Of AMSB In The Kahler Potential

The establishment of the standard model is the greatest achievement of particle physics in the last century.It successfully unified the electromagnetic and weak interaction,and achieved great success in describing the various particles observed in nature and their interactions.However,recent research shows that the standard model is still a theory that needs improvement and expansion.From the point of view of the theory itself,the 19 free parameters contained in the model can only be given by experiments,the unification of the gauge couplings cannot be realized,and the higgs sector implies severe fine-tuning problem.Experimentally,the massless neutrinos predicted in the standard model were confirmed to be of mass,and the standard model does not give a suitable dark matter candidate.A new physical model is needed to explain the difficulties encountered by the standard model.Among the candidates of new physics models,SUSY is the most popular one which could solve the fine-tunning problem,provide a natural candidate for dark matter and maintain gauge coupling unification.But the existence of supersymmetry means that the particles of standard model should have the same mass with its superpartners.Since no superpartners has been observed experimentally,the supersymmetry must be broken.In order to achieve the supersymmetry breaking,the soft breaking terms,which destroys the supersymmetry,is artificially put into the supersymmetric Lagrangian.However,in this way,a large number of soft breaking parameters are introduced into the theory,so a natural problem is how to explain these soft breaking parameters.The properties of soft breaking parameters are closely related to the mediation mechanism of SUSY breaking.Up to now,there are mainly three different mediation mechanisms: Planck mediation,gauge mediation and anomaly mediation.Among them,AMSB is always favored because it introduces the least free parameters,which is the focus of our discussion in this article.AMSB,which contains only one free parameter ,predicts tachyonic slepton masses so that the minimal scenario must be extended.The most elegant solution from aesthetical point of view is the deflected AMSB,in which additional messengers are introduced to deflect the renormalization group equation(RGE)trajectory of AMSB and push the negative slepton squared masses to positive values.But dAMSB possibly leading to strong gauge couplings below the GUT scale or Landau pole below the Planck scale.In this article,we propose a minimal Yukawa deflection scenario of AMSB from the Kahler potential through the Higgs-messenger mixing.Salient features of this scenario are discussed and realistic MSSM spectrum can be obtained.Such a scenario,which are very predictive,can solve the tachyonic slepton problem with less messenger species.Numerical results indicate that the LOSPs predicted by this scenario can not be good DM candidates.So it is desirable to extend this scenario with a Peccei-Quinn sector to solve the strong CP problem and at the same time provide new DM candidates.We propose a way to obtain a light axino mass in SUSY KSVZ axion model with Yukawa deflected anomaly mediation SUSY breaking mechanism.The axino can possibly be the LSP and act as a good DM candidate.