Top quark polarization in polarized e(+)e(-) annihilation near threshold

Top quark polarization in e(+)e(-) annihilation into tt is calculated for linearly polarized beams. The Green function formalism is applied to this reaction near threshold. The Lippmann-Schwinger equations for the S-wave and P-wave Green functions are solved numerically for the QCD chromostatic potential given by the two-loop formula for large momentum transfer and Richardson's ansatz for intermediate and small momenta. S-P-wave interference contributes to all components of the top quark polarization vector. Rescattering of the decay products is considered. The mean values [nl] of the charged lepton four-momentum projections on appropriately chosen directions n in semileptonic top decays are proposed as experimentally observable quantities sensitive to top quark polarization. The results for [nl] are obtained including S-P-wave interference and rescattering of the decay products. It is demonstrated that for the longitudinally polarized electron beam a highly polarized sample of top quarks can be produced.