Superstring Z' boson in elastic electron-positron (electron-electron) scattering

In the superstring E6 model the influence of the additional neutral Z' boson on characteristics of the processes e-e+→e-e+ and e-e- → e-e- is studied. Expressions for the helicity amplitudes and the differential cross sections of the processes e-e+ → e-e+ and e-e- → e-e- are obtained with allowance for the longitudinal polarizations of all the participating particles. The following characteristics are considered: the right-left asymmetry ARL; the P-odd polarization asymmetries Aλ1, Aλ1λ2, and Aλ1λ2; the polarization Nλ of the electron beam; the transverse-spin asymmetries Avar-phi and Avar-phi; the longitudinal electron polarizations P and P(λ1,λ2). General expressions for these characteristics are found, and quantitative estimates of them are given in the framework of the standard E6 model and the superstring E6 model