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

Abstract

In the off-diagonal basis, we discuss the contributions of the non-universal gauge boson $Z^{\prime }$ 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 $M_{Z^{\prime }}\approx \sqrt{S}$. With reasonable values of the $Z^{\prime }$ mass $M_{Z^{\prime }}$ and the coupling parameter $k_1$, $Z^{\prime }$ exchange can generate large corrections to the spin correlation observable.

Comments: 16 pages, 5 figures