In the context of the littlest Higgs （LH） model and the left-right twin Higgs （LRTH） model, we study the production of charged Higgs boson associated with top partner at the LHC. We find that, in the LH model, its cross section can be significantly larger for the scale parameter f = 500 GeV, while sharply decreases as f increases. In the LRTH model, this production process mainly transfers to the t？tb？bb final state at the Large Hadron Collider and its production rate can reach 167.2 fb.
The left-right twin Higgs （LRTH） model predicts the existence of the neutral Higgs bosons （h, φ0）, which can be produced in pairs （φ0φ0, hh, φ0h） via γγ collisions at the next generation e＋eInternational Linear Collider （ILC）. Our numerical results show that the production cross section of the neutral Higgs boson pair φ0φ0 can reach 8.8 fb. The subprocess γγ → φ0φ0 might be used to test the LRTH model in future ILC experiments.
Considering the process pp→VH ＋X（V = W or Z） is a significant channel for searching for a light Higgs boson, we calculate the contributions of the littlest Higgs model with T-parity （called LHT model） to its production cross section. We find that, in most of the parameter space, the value of the relative correction parameter R is very small. However, with reasonable values of the free parameters, its value can be significantly larger.
The new particles predicted by the littlest Higgs model with T-parity (called LHT model) can induce the lepton flavor violation (LFV) couplings at the one-loop level,which can add contributions to some LFV processes.Taking into account the constraints of the experimental data on the relevant free parameters,we calculate the branching ratios of the LFV decay processes Z → l ˉl and τ-→μ-P 1 P 2 with P 1 P 2 = π + π-,K + K-,and K0 ˉK 0 in the context of this new physics model.We find that the LHT model can indeed make significant contributions to some of these LFV decay processes.The Z factory option for the future high energy e + e-collider experiments will give severe constraints on the LHT model.
YUE ChongXing,MA Wei,ZHANG TingTing,LIU Wei & LIU JinYan Department of Physics,Liaoning Normal University,Dalian 116029,China
Type-III seesaw scenario predicts the existence of the heavy charged leptons, which might generate observable signals in future collider experiments. We consider the contributions of these new particles to the process e＋e- →HH. We find that, for the large mixing between the light and heavy leptons, these new particles can indeed generate significant contributions to this process.
The neutrino-electron scattering process is sensitive to the standard model(SM)and the new physics beyond the SM.We calculate the corrections of the littlest Higgs model and the SU(3)simple group model to theνe e scattering cross section.Using the LSND experimental measured values,we obtain the bounds on the relevant free parameters,which might be compatible with those from the electroweak precision data.
In the context of the topcolor-assisted technicolor （TC2） model, we consider the production of the neutral scalar S （7~t~ or ht~） associated with a photon at the LHC and compare our results with those given by the minimal supersymmetric extension of the Standard Model （MSSM）. We find that its production cross section is larger or smaller than that of the scalar particle predicted by the MSSM model, depending on the values of the relevant free parameters.
