  The study of the top quark's properties is an important part of the LHC
programme. In earlier work, we have studied the rare decay $t \to b \bar b c$,
using effective operators to capture the effects of physics beyond the Standard
Model. However top decay is primarily sensitive to new physics in the sub-TeV
energy regime. If this new physics resides at a higher energy scale, then one
needs to turn to single-top production. In this paper, we use the $s$-channel
and $t$-channel single-top production measurements to constrain the new physics
parameter space associated with such contact interactions. We also study the
net top polarization as a means to distinguish between contributions from
operators involving different fermion chiralities and Lorentz structures.
