Pair production of Higgs bosons associated with Z boson in the left-right twin Higgs model at the ILC

The left-right twin Higgs (LRTH) model predicts the existence of three additional Higgs bosons: one neutral Higgs ϕ0 and a pair of charged Higgs bosons ϕ±. In this paper, we studied the production of a pair of charged and neutral Higgs bosons associated with standard model gauge boson Z at the ILC, i.e., e+e−→Zϕ+ϕ− and e+e−→Zϕ0ϕ0. We calculate the production rate and present the distributions of the various observables, such as, the distributions of the energy and the transverse momenta of final Z-boson and charged Higgs boson ϕ−, the differential cross section of the invariant mass of charged Higgs bosons pair, the distribution of the angle between charged Higgs bosons pair and the production angle distributions of Z-boson and charged Higgs boson ϕ−. Our numerical results show that, for the process e+e−→Zϕ+ϕ−, the production rates are at the level of 10−1 fb with reasonable parameter values. For the process of e+e−→Zϕ0ϕ0, we find that the production cross section are smaller than 6×10−3 fb in most of parameter space. However, the resonance production cross section can be significantly enhanced.