Direct Signals of Low Scale Gravity at $e^+ e^-$ Colliders

Gravity can become strong at the TeV scale in the theory of extra dimensions. An effective Lagrangian can be used to describe the gravitational interactions below a cut-off scale. In this work, we study the associated production of the gravitons with a $Z$ boson or a photon at $e^+ e^-$ colliders of energies of LEPII to the Next Linear Colliders (NLC) ($\sqrt{s}=0.25-1.5$ TeV) and calculate the sensitivity to the new interactions. We also obtain the limit on the cut-off scale using the present data from LEPII.