Model-Independent $Z^{\mathrm{\prime }}$ Limits from Electron-Electron Collisions

Model independent constraints on the mass of an extra neutral gauge boson and its couplings to charged leptons are given for the $e^{-}{e}^{-}$ option of a future linear collider. Analytic exclusion limits are derived in the Born approximation. The results are compared with those of the $e^{+}{e}^{-}$ mode. The influence of radiative corrections is discussed.