Supersymmetric QCD flavor-changing top quark decay

Abstract

We present a detailed and complete calculation of the gluino and scalar quarks contribution to the flavor-changing top quark decay into a charm quark and a photon, gluon, or a ${Z}^{0}$ boson within the minimal supersymmetric standard model including flavor-changing gluino-quark-scalar-quark couplings in the right-handed sector. We compare the results with the ones presented in an earlier paper where we considered flavor-changing couplings only in the left-handed sector. We show that these new couplings have important consequences leading to a large enhancement when the mixing of the scalar partners of the left- and right-handed top quark is included. Furthermore $\mathrm{CP}$ violation in the flavor-changing top quark decay will occur when a SUSY phase is taken into account.