Flavor-changing top quark decays in R-parity-violating SUSY

The flavor changing top quark decays $t \to cV $ (V=Z,\gamma,g) induced by R-parity-violating couplings in the minimal supersymmetric model are evaluated. We find that $Br(t \to cV)$ can be enhanced significantly relative to that in the SUSY model with R-parity. Our results show that $Br(t \to cg) \sim 10^{-3}$, $Br(t \to cZ) \sim 10^{-4}$ and $Br(t \to c\gamma) \sim 10^{-5}$, which are observable at the upgraded Tevatron and the LHC.