Information and discrimination from b quark production on the Z resonance

We introduce and define operatively, in a model-independent way, a new ''heavy'' b-vertex parameter ηb that can be derived from the measurement of a special polarization asymmetry for production of b quarks on the Z resonance. We show that the combination of the measurement of ηb with that of a second and previously defined ''heavy'' b-vertex parameter δbV can discriminate a number of models of new physics that are associated with different ''trajectories'' in the plane of the variations of the two parameters. This is shown in particular for some popular SUSY and technicolor-type models. In general, this discrimination is possible if a measurement of both parameters is performed