Search for flavor-changing neutral current decays of the top quark in $p \bar{p}$ collisions at $\sqrt{s} = 1.8$ TeV

We search for the flavor-changing neutral current decays of the top quark t{r_arrow}q{gamma} and t{r_arrow}qZ (here q represents the c and u quarks) in {bar p}p collisions at {radical}(s)=1.8 TeV . We use a dataset ({integral}Ldt{approximately}110 pb{sup {minus}1}) collected during the 1992{endash}1995 run of the Collider Detector at Fermilab. We set 95{percent} confidence level limits on the branching fractions B(t{r_arrow}q{gamma}){lt}3.2{percent} and B(t{r_arrow}qZ){lt}33{percent} , consistent with the standard model. {copyright} {ital 1998} {ital The American Physical Society}