  The Tevatron, where the top quark was discovered, and the currently
functional Large Hadron Collider (LHC), with copiously produced top pairs,
enable a detailed study of top-quark properties. In particular, they can be
used to test the couplings of the top quark to gauge bosons. Several extensions
of the standard model (SM) can give rise to anomalous couplings of the top
quark to gauge bosons, in particular, the gluons. In this work we examine how
top-quark polarization, which is predicted to be negligibly small in the SM,
can be used to measure chromomagnetic and chromoelectric couplings of the top
quark to gluons. We lay special emphasis on the use of angular distributions
and asymmetries of charged leptons arising from top decay as measures of top
polarization and hence of these anomalous couplings. Sensitivities that may be
reached at the Tevatron and the LHC are obtained.

High Energy Physics - Phenomenology