In an $R$-parity nonconserving supersymmetric theory, the lighter stop can dominantly decay into $b\mu$ and $b\tau$ if $R$-parity breaking has to explain the neutrino mass and mixing pattern suggested by the data on atmospheric muon neutrinos. This should give rise to dilepton $+$ dijet and single $-$ lepton $+$ jets, signals identical with those of the top quark at the Fermilab Tevatron. One can thus constrain the stop parameter space using the current top search data and can similarly look for the first signals of supersymmetry at the upgraded runs of the Tevatron.

• Received 17 March 2000

DOI:https://doi.org/10.1103/PhysRevLett.85.248