Z' Reservation at LEP2

Abstract

We consider the possibility that one extra $Z\equiv Z^{\prime }$ exists with arbitrary mass and fermion couplings that do not violate (charged) lepton universality. We show that, in such a situation, a functional relationship is generated between the \underline{deviations} from the SM values of three leptonic observables of two-fermion production at future $e^{+}{e}^{-}$ colliders that is completely independent of the values of the $Z^{\prime }$ mass and couplings. This selects a certain region in the 3-d space of the deviations that is \underline{characteristic} of the model ($Z^{\prime }$ "reservation"). As a specific and relevant example, we show the picture that would emerge at LEP2 under realistic experimental conditions.

Comments: 10 pages, LaTeX, 3 uuencoded ps figures