unpolarized beams. In Table 1, we present the values of $M_s$ that one can probe at 99% confidence level.

$$\begin{array}{|c|r|c|c|c|c|c|c|}
\hline
\sqrt{s}    
           & d =               & 2    & 3    & 4    & 5    & 6    \\ 
\hline\hline
0.5 
           & {\rm polarized}   & 4.53 & 2.79 & 2.01 & 1.60 & 1.35 \\
           & {\rm unpolarized} & 3.16 & 2.09 & 1.59 & 1.30 & 1.12 \\
\hline\hline
1.0
           & {\rm polarized}   & 7.40 & 4.63 & 3.41 & 2.76 & 2.36 \\
           & {\rm unpolarized} & 5.36 & 3.57 & 2.74 & 2.28 & 2.36 \\
\hline
\end{array}$$

Table 1. [ *99% C.L. discovery limits on the string scale $M_S$ for an ADD scenario using (graviton) radiative Bhabha scattering, for different numbers of extra dimensions. An integrated luminosity of $500~fb^{-1}$ has been assumed. All numbers are in TeV.*]{}

If one compares these with the corresponding reach of the process[@GRW; @MPP; @Wilson] $e^+ e^- \to \gamma + \not{\!\!E}$, one will notice that search limits are approximately of the same order. However, the comparison should not be made too literally, because of several reasons. First, the polarization efficiencies in our case, while matching with those of [@Wilson], are different from those of 