Probing top quark decay into a light top squark in the supersymmetric standard model at the upgraded Fermilab Tevatron

We investigate the possibility of observing the exotic decay mode of the top quark into the lightest top squark (t1) and neutralino (χ10) in the minimal supersymmetric standard model with R parity at the upgraded Fermilab Tevatron. First we examine the bounds for the branching fraction B(t→t1χ10) from the available experimental data, and then consider all possible backgrounds and investigate the possibility of observing this final state at the Tevatron. We find that this final state is unobservable at run 1. However, run 2 can either discover it, or establish strong limits (∼1%) on the branching fraction of this decay. copyright 1998 The American Physical Society