Two Examples Of New Physics Beyond SM Dark Matter And Supersymmetry

In this thesis, we attempt to examine new physics beyond Standard Model through Dark Matter detection and Collider searches. First, upper limits on GeV gamma-ray flux reported by Fermi-LAT collaboration are considered to examine two decaying dark matter models, one via grand unification scale suppressed operators and the other via R-parity violating operators. We find that the gamma-ray flux via inverse Compton scattering in the Fornax cluster disagrees with recent Fermi-LAT measurements for decaying dark matter scenario. Then we use decoupling MSSM of light stau and non-decoupling MSSM to explain125GeV Higgs boson and its prop-erties. For decoupling limit, we study light stau’s contribution to di-photon decay and its phenomenology of direct search on LHC, and we focus on two mechanisms that enhance the stau production. For non-decouping limit, we only identify a small parameter region that is consistent with all bounds. Finally, we study non-decoupling MSSM in which bb does not dominate the Higgs decay, and find that the discovery of H H→hh signal would require more than14TeV LHC with more than100fb-1of data to see any over three sigma deviation.