Alternative interpretation of the Fermilab Tevatron top events

Abstract

We propose an alternative interpretation of the top events discovered at the Fermilab Tevatron in 1995. Given that the charge of the b quark jet cannot be measured for the whole sample with certainty, the signal can be due to a quark of charge $\ensuremath{-}4/3$ at the reported mass, i.e., 174 GeV, while the top quark is actually heavier, say above 230 GeV. We point out in this paper that such a scenario is actually hinted at by the latest precision electroweak measurements of Z decay. To rule out this possibility in the future, the b quark jet charge analysis has to become definitive, or the single ``top'' production cross section has to be measured.