  Top quark decays are of particular interest as a mean to test the standard
model (SM) predictions, both for dominant (t -> b + W) and rare decays (t -> q
+ W, cV, cVV, c phi^{0}, bWZ). As the latter are highly suppressed, they become
an excellent window to probe the predictions of thories beyond the SM. In
particular, we evaluate the corrections from new physics to the CKM-suppressed
SM top quark decay t -> q + W (q = d, s), both within the an effective model
with right-handed currents and the MSSM. We also discuss the perspectives to
probe those predictions at the ILC.

High Energy Physics - Phenomenology