The decays gluino -> stop₁ b-quark W and gluino -> stop₁ c-quark and phenomenological implications in supersymmetric theories

We show that the decay gluino -> stop_1 b-quark W is important and can even be dominant in the region of parameter space where it is kinematically allowed. We discuss phenomenological implications within the Minimal Supersymmetric Standard Model and models with broken R-parity. We consider the flavour diagonal case as well as a possible mixing between squarks of different generations. In the latter case also the decay gluino -> stop_1 c-quark is potentially important. We show that the decay gluino -> stop_1 b-quark W is sensitive to the stop mixing angle. Furthermore we demonstrate that in scenarios with a higgsino--like LSP the gluino decays mainly into final states containing top quarks or a light stop if allowed by kinematics.