PROBING HIGGS BOSON-INDUCED AND SUPERSYMMETRY-INDUCED CP VIOLATION INTOP-QUARK PRODUCTION BY (UN-) POLARIZED ELECTRON-POSITRON COLLISIONS

We consider, both for unpolarized and longitudinally polarized electro n beams, the reaction e(+)e(-) --> <t(t)over bar> with subsequent semi leptonic t and nonleptonic (t) over bar decay and vice versa and inves tigate optimized angular correlations which are sensitive to CP non-co nservation in the <t(t)over bar> production vertex. We calculate these correlations for two-Higgs-doublet extensions and the minimal supersy mmetric extension of the Standard Model (SM) with CP violation beyond the Kobayashi-Maskawa phase. While the sensitivity of the optimal corr elation for tracing dispersive CP effects is enhanced with longitudina lly polarized electron beams, we find that the sensitivity of the best correlation for probing absorptive CP effects is almost independent o f the polarization degree.