Flavor-changing top quark decay within the minimal supersymmetric standard model

We present the results of the gluino and scalar quark contribution to the flavor-changing top quark decay into a charm quark and a photon, gluon, or a ${\mathit{Z}}^0$ boson within the minimal supersymmetric standard model. We include the mixing of the scalar partners of the left- and right-handed top quark. This mixing has several effects, the most important of which is to greatly enhance the c Z decay mode for large values of the soft SUSY-breaking scalar mass ${\mathit{m}}_{\mathit{S}}$ and to give rise to a GIM-like suppressions in the c γ mode for certain combinations of parameters.