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Why e+ e- to T Tbar is Different

Stephen Parke
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Abstract

Unlike other examples of fermion pair production in e+ e- collisions, we show that top-quark pairs are produced in an essentially unique spin configuration in polarized e+ e- colliders at all energies. Since the directions of the electroweak decay products of polarized top-quarks are strongly correlated to the top-quark spin axis, this unique spin configuration leads to a distinctive topology for top-quark pair events which can be used to constrain anomalous couplings to the top-quark. A significant interference effect between the longitudinal and transverse W-bosons in the decay of polarized top-quarks is also discussed.

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Stephen Parke. 1998-07-31. Why e+ e- to T Tbar is Different. https://arxiv.org/abs/hep-ph/9807573

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