  We consider the momentum distribution and the polarization of an inclusive
heavy fermion in a process assumed to arise from standard-model (SM)
$s$-channel exchange of a virtual $\gamma$ or $Z$ with a further contribution
from physics beyond the standard model involving $s$-channel exchanges. The
interference of the new physics amplitude with the SM $\gamma$ or $Z$ exchange
amplitude is expressed entirely in terms of the space-time signature of such
new physics. Transverse as well as longitudinal polarizations of the electron
and positron beams are taken into account. Similarly, we consider the cases of
the polarization of the observed final-state fermion along longitudinal and two
transverse spin-quantization axes which are required for a full reconstruction
of the spin dependence of the process. We show how these model-independent
distributions can be used to deduce some general properties of the nature of
the interaction and some of their properties in prior work which made use of
spin-momentum correlations.
