6533b854fe1ef96bd12ae0b8

RESEARCH PRODUCT

O(alpha_s) Spin-Spin Correlations for Top and Bottom Quark Production in e+ e- Annihilation

J. PeñarrochaJ. BernabeuM.m. Tung

subject

PhysicsQuarkQuantum chromodynamicsNuclear and High Energy PhysicsParticle physicsAnnihilationmedia_common.quotation_subjectHigh Energy Physics::LatticeHigh Energy Physics::PhenomenologyBremsstrahlungFOS: Physical sciencesFísicaAsymmetryBottom quarkHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Pair productionHigh Energy Physics::ExperimentSpin-½media_common

description

We present the full O(alpha_s) longitudinal spin-spin correlations for heavy-quark pair production at e+ e- high-energy colliders in closed analytical form. In such reactions, quark and antiquark have strongly correlated spins, and the longitudinal components are dominant. For the explicit computation of the QCD bremsstrahlung contributions, new phase-space integrals are derived. Explicit numerical estimates are given for t t_bar and b b_bar production. Around the Z-peak, QCD one-loop corrections depolarize the spin-spin asymmetry for bottom quark pairs by approximately -4%. For top pair production, we find at 350GeV a 0.6% increased polarization over a value of 0.4 in the longitudinal correlation. For more than 1 TeV the O(alpha_s) corrections enhance depolarization to -2% in the top-pair case.

10.1016/s0370-2693(97)01438-xhttp://hdl.handle.net/10550/42967