Beyond The Standard Model Explanations To Flavor Observables

Abstract

After 125 GeV Higgs boson discovery, minimal supersymmetric standard model with gauge mediation becomes dangerous. Gauge mediation is thought to be one of the simplest solutions for SUSY flavor problem, such a virtue of gauge mediation is now in danger. In this thesis, we consider right-handed Majorana neutrino as supersymmetry breaking messenger. We can get additional tri-linear coupling AU at the messenger scale after integrating out the right-handed Majorana neutrino. Through additional AU term, we can realize maximal stop mixing scenario which is hardly possible in genuine gauge mediation mechanism. However, mediating SUSY breaking effects through Yukawa coupling reintroduces the SUSY flavor problem in the model unless neutrino Dirac Yukawa is proportional to identity matrix. Making neutrino Dirac Yukawa the identity matrix is not a bizzarre assumption, but it is easily achieved by importing discrete symmetry. Discrete symmetry is also useful to explain the tri-bi maximal form of the PMNS matrix. Tri-bi maximal form indicates the zero θ13 mixing of neutrinos, which is rejected by RENO and Daya Bay collaborations. To incorporate non-zero θ13, we introduce small deviation parameters in the Majorana mass matrix and neutrino Dirac Yukawa matrix. Deviation parameters in the neutrino Dirac Yukawa can produce sizeable charged lepton flavor violation, we examine how large deviation in the neutrino Dirac Yukawa matrix is allowed by present and forthcoming charged lepton flavor violation experiments.