\begin{table}%t3
%\centering
\par
\caption{\label{tab:conv}Conversion factor $A$ for Eq.~(1) calculated for different   galaxy template ages and metallicities relative to the
  solar value, $Z_{\odot}=0.02$.}
\begin{tabular}{lcccc}
  \noalign{\smallskip}
\hline\hline
  \noalign{\smallskip}
Age &0.02~$Z_{\odot}$ & 0.2~$Z_{\odot}$ & 0.4~$Z_{\odot}$ & 1~$Z_{\odot}$ \\
  \noalign{\smallskip}
\hline
  \noalign{\smallskip}
10~Myr & 1.1 & 1.3 & 1.4 & 1.5\\
50~Myr & 1.7 & 1.9 & 2.3 & 2.9\\
100~Myr& 2.3 & 2.9 & 3.7 & 5.5\\
200~Myr& 3.5 & 5.1 & 7.3 & 14.9\\
  \noalign{\smallskip}
\hline
\end{tabular}
\end{table}