New directions for top quark polarization in thet-channel process

We define three orthogonal axes to investigate the top-quark polarization in the t-channel single-top process. We provide expressions for the polarization in these axes in terms of anomalous $Wtb$ couplings. It is found that the polarizations in the two axes orthogonal to the spectator quark axis are very sensitive to an anomalous coupling involving a b̄Lσ^μνtR dipole term. In particular, an asymmetry based on the polarization normal to the production plane is more sensitive to the imaginary part of this coupling than previously studied observables.