Probing New Gauge Boson Couplings via Three-Body Decays
  We examine the possibility of using rare, 3-body decays of a new neutral gauge boson, \ztwo, to probe its gauge couplings at hadron colliders. Specifically, we study the decays $\ztwo\to W\ell\nu$ and $\ztwo\to Z\nu\bar\nu$ and find that much knowledge of the \ztwo\ properties can be obtained from these processes. In particular, these decay modes can yield valuable information on the amount of $Z_1-Z_2$ mixing, on the generation dependence of the \ztwo\ couplings, on the properties of the new generator associated with the \ztwo, as well as being used to distinguish between possible extended models. The analogous 3-body decays into a new, heavy charged gauge boson, $\ztwo\to W_2^\pm\ell^\mp\nu$, are also investigated in models where this can occur. 
J.L. Hewett and T.G. Rizzo