Study On Possible Physical Signs Of Several Typical New Particles

The standard model (SM) provides an successful effective field theory description of al-most all particle physics experiments. However, the theoretical defects of the SM indicate thepossibility for the existing of new physics (NP). The littlest Higgs model with T-parity (LHT),the beautiful mirrors model and the topflavor seesaw model are remained popular candidates fornew physics beyond the SM. These models predict some new particles, which can be regardedas typical features of these models. In this thesis, we study the conceivable effects of new par-ticles in the LHT model, the beautiful mirrors model and the topflavor Seesaw model to somemeaningful specific processes.We study pair production of the mirror leptons in association with a gauge boson V (γ orZ) in the future ILC experiments. The numerical results show that the mirror leptons can benumerously produced via the processes e+e→V LiLj, and their signatures might be observedin the future ILC experiments. In the context of topflavor seesaw model, we study the productionof the heavy charged gauge boson WHassociated with a top quark at the LHC. It is found thatthe backgrounds can be significantly suppressed with sets of kinematic cuts, and the signal ofthe heavy charged boson might be detected at the LHC. Furthermore, we study the correctioneffects of the bottom partner B′predicted in the beautiful mirrors model on the productioncross section σ(Zb) and the Z polarization asymmetry AZ. Our numerical results show that,with reasonable values of the relevant parameters, B′can generate large corrections to σ(Zb)and AZ. Any visible signal from these new particles will give some new clues to NP. One ofthe important tasks of the LHC is to find the Higgs boson. Searching for the Higgs boson is animportant task of the LHC. Recently, the CMS and ATLAS collaborations have independentlyreported the discovery of a neutral scalar particle that seems consistent with the SM Higgsboson with a mass of about126GeV. How to differentiate different new physics models whichpredict Higgs bosons? And the further research is needed to confront with these questions. Themodel predictions for the Higgs signal rates have been compared with the experimental data invarious new physics models. And the phenomenology can be used to test the relevant modelsand distinguish them from other new physics models. Basing on this purpose, we calculate therates of the main Higgs search channels normalized to the SM prediction in the LHT model. Wehope that our work is useful for testing the LHT model and giving some necessary explanationsfor the experiment data from LHC.