Studying top quark decay into the polarizedWboson in the topcolor-assisted technicolor model

We study the decay mode of the top quark decaying into $Wb$ in the topcolor-assisted technicolor (TC2) model where the top quark is distinguished from other fermions by participating in a strong interaction. We find that the TC2 correction to the decay width $\Gamma (t\to bW)$ is generally several percent and the maximum value can reach 8% for the currently allowed parameters. The magnitude of such a correction is comparable with the QCD correction and larger than that of the minimal supersymmetric model. Such a correction might be observable in the future colliders. We also study the TC2 correction to the branching ratio of top quark decay into the polarized $W$ bosons and find the correction is below 1%. After considering the TC2 correction, we find that our theoretical predictions about the decay branching ratio are also consistent with the experimental data.