\begin{table}%t3
%\centering
 \caption{\label{table4}X-ray luminosity (assuming
isotropy, $L_{\rm X} ^{\rm iso}$, and after beaming correction, $L_{\rm X}
^{\rm corr}$), energy emitted during the prompt $\gamma$-ray event
(assuming isotropy, $E_{\gamma} ^{\rm iso}$) in units of $10^{51}$ erg,
and beaming angle for BeppoSAX GRBs with a measured beaming angle
(extracted from \mbox{literature}). }
\small%\centering
\par
\begin{tabular}{ccccc}
  \hline\hline\noalign{\smallskip}
  GRB~name & $ L_{\rm X} ^{\rm iso}$           & $ E_{\gamma} ^{\rm iso}$ & $\rm \theta$ & $  L_{\rm X} ^{\rm corr}$   \\
           & $\rm 10^{44}$ erg s$^{-1}$ & $\rm 10^{51}$ erg       &  rad & $\rm 10^{44}$ erg s$^{-1}$ \\
  \hline\noalign{\smallskip}
\object{GRB~970228} & 28.6  & 9.9    & $\rm >$$0.32$  & $\rm >$$1.46$   \\
\object{GRB~970508} & 16.1  & 3.5    & 0.391    &  1.23     \\
\object{GRB~971214} & 147   & 125    & $\rm >$$0.1$   & $\rm >$$0.74$   \\
\object{GRB~980613} & 7.21  & 4.26   & $\rm >$$0.226$ & $\rm >$$0.2$    \\
\object{GRB~980703} & 37.4  & 74.1   & 0.2      & 0.75      \\
\object{GRB~990123} & 373   & 692    & 0.089    & 1.48      \\
\object{GRB~990510} & 269.7 & 144.5  & 0.054    & 0.39      \\
\object{GRB~990705} & --   & 79.4   & 0.096    & --       \\
\object{GRB~990712} & --   & 3.32   & $\rm >$$0.777$ & --       \\
\object{GRB~000210} & 6.96  & 130    & $\rm >$$0.139$ & $\rm >$$0.07$   \\
\object{GRB~000214} & 3.4   & 3.17   & $\rm >$$0.115$ & $\rm >$$0.023$  \\
\object{GRB~000926} & 335   & 155    & 0.140    & 2.14      \\
\object{GRB~010222} & 377   & 375    & 0.08     & 13.1      \\
\object{GRB~011121} & 5.1   & 3.74   & 0.145    & 0.05      \\
\object{GRB~011211} & 20    & 68.8   & 0.115    & 0.12      \\
\hline
\end{tabular}
\end{table}