Polarization effects in e/sup +/e/sup -/. -->. Z/sup 0/. gamma

Polarizations of Z/sup 0/ and ..gamma.. in the reaction e/sup +/e/sup -/..-->..Z/sup 0/..gamma.. near the Z/sup 0/ peak are obtained through the density matrix of Z/sup 0/ and Stokes parameters of ..gamma.., respectively. Their dependence on the linear polarizations of incident electron-positron beams and their influence on the decay of Z/sup 0/ into two spin-(1/2 fermions f and f-bar are discussed in the standard model. It is shown that the longitudinal polarization of incident electron beam can enhance the circular polarization of the outgoing photon beam.