The Possible Signals Of The Littlest Higgs Model With T-parity At The ILC

Content: The standard model(SM) is one of the greatest achievements in physics in the 20th century. The Standard Model(SM) of elementary particles has achieved much success. However, it suffers from the problems of too many free prameters, triviality and unnaturalness, etc. It still suffers some deviations from experimental data. People usually take the view that the SM is a low energy effective theory and it will be modified at a higher scale. The little Higgs theory is one kind of the popular new physical theories.At the first chapter we have given a brief introducton of the little Higgs theory. LH model is one of the simplest Higgs models, it has all essential features of the little Higgs models. However, the LH model suffers from severe constraints from precision electroweak measurement, which could only be satisfied by fine tunning the model parameters. To avoid this problem, T-parity has been introduced, which forms called LHT model. The LET model is one of the attractive little Higgs models, most of works of this article are done in this model. LHT model predicts some new particles which may be detected by future high-energy collider experiments, such as LUC and ILC. It has great importance to investigate the new particles.We first estimate the corrections of the LHT model to the production cross section of the processes e~+e~-→ZH, e~+e~-→(?)_ev_eH and e~+e~-→t(?)H, and give a theoretic predict that can be tested by experiments. The results are very important for studying Higgs properties and test new physics beyond the SM.Second, we have considered pair production of the T-odd leptons and discussed the possible of detecting these new particles in future ILC experiments. We find that, as long as the T-odd leptons are not too heavy, they can be copiously produced in pairs via the processes e~+e~-→(?)_iL_j and their signatures might be observed in future ILC experiments. Thus, we expect that the future ILC experiments can be seen as an ideal tool to detect the T-odd leptons predicted by the LHT model.Finally, we consider production of the T-odd scalars (φ~±,φ~0和φ~p) in association with T-odd gauge bosons at the LHC. The production cross sections are small in most of the parameter space of the LHT model. However, the process q(?)'→φ~+B_H can generate the characteristic signal events with a charged lepton and large missing energy, the possible signature ofφ~+ might be detected via this process at the LHC.