Anomaloust-c-gcoupling: The connection between single top quark production and top quark decay

Continuing earlier work, we examine the constraint on an anomalous $t$-$c$-$g$ coupling from top quark decay. We find that from current CDF measurements of the branching ratio $t\to \mathrm{Wb}$, the minimum scale at which new physics can strongly modify the $t$-$c$-$g$ coupling is ${\Lambda }_{\mathrm{tcg}}$ $>~$ about 950 GeV. At the upgraded Fermilab Tevatron, single top quark production can constrain ${\Lambda }_{\mathrm{tcg}}$ $>~$ 4.5 TeV. The connection between $t$-$c$ production and the decay $t\to \mathrm{cg}$ is examined, showing how constraints on one lead to a constraint on the other.