We present a search for flavor changing neutral currents in decays of top quarks. The analysis is based on a search for t (t) over bar -} l''vl (l) over bar + jets (l, l'' = e. mu) final states using 4.1 fb(-1) of integrated luminosity of p (p) over bar collisions at sqrt(s) = 1.96 TeV.
We extract limits on the branching ratio B(t -} Zq) (q = u, c quarks), assuming anomalous tuZ or tcZ couplings. We do not observe any sign of such anomalous coupling and set a limit of B { 3.2% at 95% C.L.