Flavor changing scalar couplings and $tγ(Z)$ production at hadron colliders

Abstract

We calculate the contributions of the flavor changing scalar ($FCS$) couplings arised from topcolor-assisted technicolor ($TC2$) models at tree-level to the $tγ$ and $tZ$ production at the Tevatron and $LHC$ experiments. We find that the production cross sections are very small at the Tevatron with $\sqrt{s}=1.96TeV$, which is smaller than 5 fb in most of the parameter space of $TC2$ models. However, the virtual effects of the $FCS$ couplings on the $tγ(Z)$ production can be easily detected at the $LHC$ with $\sqrt{s}=14TeV$ via the final state $γl\barνb$ ($l^{+}l^{-}l\barνb$).