Non - universal gauge boson Z ′ and the spin correlation of top quark pair production at e − e + colliders
نویسنده
چکیده
In the off-diagonal basis, we discuss the contributions of the non-universal gauge boson Z ′ predicted by the topcolor-assisted technicolor (TC2) model to the spin configurations and the spin correlation observable of the top quark pair production via the process e−e+ → tt̄. Our numerical results show that the production cross sections for the like-spin states, which vanish in the standard model, can be significantly large as MZ′ ≈ √ S. With reasonable values of the Z ′ mass MZ′ and the coupling parameter k1, Z ′ exchange can generate large corrections to the spin correlation observable. PACS number: 12.10.Dm, 14.65.Ha, 12.15.Lk, 12.60.Cn. ∗E-mail:[email protected]
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