Double Charged Leptons In High Energy Linear E ~ + E ~ - To Produce Collider

Although the success of the Standard Model as a way to correctly describe the interactions between particles is beyond any doubt, there are good reasons to believe that the standard model is not the ultimate theory to describe Nature. Dark energy, neutrino masses, and the actual mechanism of electroweak breaking are among the pressing issues, which has been one of the leading motivations for many theoretical considerations beyond the standard model. In many new physics models,gauge symmetry will be expended, therefore, the new particles would be introduced. So it is important to explore the properties of the new particles and the possibility of detecting the new particle in high energy experiment.Many new physics models, such as SM4, MLFVseesawⅢ, LL,R, ExtendedlsospinModel, all pre-dicted the existence of heavy fermions, and doubly charged heavy lepton is the particular one. This paper sum up the basic property of heavy fermions, detailed introduction the general aspects (the coupling, decay and production) of doubly charged heavy lepton, especially predicted by LL,R, ExtendedIsospinModel.We consider production of the doubly charged leptons X±±via e+e-、γγ and eγ collisions at the high-energy linear e+e-colliders. First, we research production of the doubly charged leptons via e+e-collision. It is obvious that the doubly charged leptons can be pair produced by the s-channel γ exchange and Z exchange. We assume200GeV≤Mx≤700GeV, c.m. energy (?)s=1.5TeV, the production cross section in the range of212～110f6. Certainly, the doubly charged leptons can also be pair produced by the t-channel W±exchange via e+e-collisions. It is obvious that the production cross section is proportional to the factor|vi|4and its value is very small, which can be neglected. Then, we study production of the doubly charged leptons via γγ collision: γ(p1)γ(p2)�'X--(P3)X--(P4).In most of the parameter space, the production cross section decreases with the increasing lepton mass MX and its value can reach several thousand fb. Finally, we research production of the doubly charged leptons via eγ collision:e(p1)γ(p2)�'X--(P3)W+(P4). Due to the mixing parameter ve is small, the production cross section is too small to be used to study the properties of the doubly charged leptons, even with MX=200GeV,the value of the cross section is small than0.02fb. Certainly, if one new physics model is constructed, in which the doubly charged leptons can have large mixing with the SM leptons, then this process is needed to be reconsidered at the high-energy e+e-collider.