O(ALPHA(S)) SPIN-SPIN CORRELATIONS FOR TOP AND BOTTOM QUARK PRODUCTION IN E(-) ANNIHILATION()E()

We present the full O(alpha(s)) longitudinal spin-spin correlations fo r heavy-quark pair production at e(+)e(-) high-energy colliders in clo sed analytical form. In such reactions, quark and antiquark have stron gly correlated spins, and the longitudinal components are dominant. Fo r the explicit computation of the QCD bremsstrahlung contributions, ne w phase-space integrals are derived. Explicit numerical estimates are given for tr and bb production. Around the Z-peak, QCD one-loop correc tions depolarize the spin-spin asymmetry for bottom quark pairs by app roximately -4%. For top pair production, we find at 350 GeV a 0.6% inc reased polarization over a value of 0.4 in the longitudinal correlatio n. For more than 1 TeV the O(alpha(s)) corrections enhance depolarizat ion to -2% in the top-pair case. (C) 1998 Elsevier Science B.V.