Probing the CP nature of Higgs boson through e^-e^+ --> e^-e^+ phi
  We study the production of Higgs boson (phi) via the e^{-}e^{+}--> e^{-}e^{+} phi process at a future International Linear Collider (ILC) with sqrt{S}=1 TeV. At this energy the ZZ-fusion rate, as predicted by the Standard Model, dominates over the associated ZH production rate. Here, we consider a class of theory models based on the effective phi-VV (with V=Z, gamma) couplings generated by dimension-6 operators. We also show how to use the kinematical distributions of the final state leptons to discriminate the CP-even and CP-odd Higgs bosons produced at the ILC, when the phi-gamma-gamma coupling dominates the Higgs boson production rate. 
Qing-Hong Cao, F. Larios, G. Tavares-Velasco and C.-P. Yuan