Top quark decay t -> cb\bar{b} in topcolor-assisted technicolor models

Abstract

Topcolor-assisted technicolor (TC2) model predicts the existence of the top-pions and the CP-even top-Higgs with large flavor-changing couplings to the top quark, which at tree-level can mediate the top quark three-body decay t -> cb\bar{b}. In this work we study this decay, showing the dependence of the decay rate on the relevant TC2 parameters and comparing the results with the predictions in the minimal supersymmetric model. We find that the decay rate in the TC2 model is much larger than in the minimal supersymmetric model and, in a large part of the parameter space, the TC2 prediction may reach the detectable level of the LHC.