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Non-universal gauge boson $Z'$ and the spin correlation of top quark pair production at $e^{-}e^{+}$ colliders

Chong-Xing Yue·Li-Na Wang
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Abstract

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 $e^{-}e^{+}\to t\bar{t}$. 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 $M_{Z'}\approx \sqrt{S}$. With reasonable values of the $Z'$ mass $M_{Z'}$ and the coupling parameter $k_{1}$, $Z'$ exchange can generate large corrections to the spin correlation observable.

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Chong-Xing Yue, Li-Na Wang. 2006-12-05. Non-universal gauge boson $Z'$ and the spin correlation of top quark pair production at $e^{-}e^{+}$ colliders. https://doi.org/10.1088/0954-3899%2F34%2F1%2F010

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