\begin{table}%t6
\caption{H$\beta$ corrections for gradients.}
%\centerline
{
\begin{tabular}{lcccc}
\hline\hline
\multicolumn{1}{c}{Galaxy}
&\multicolumn{1}{c}{aperture}
& \multicolumn{1}{c}{{\it EW}O[III]}
& \multicolumn{1}{c}{Quality}
& \multicolumn{1}{c}{{\it EW}H$\alpha$}
\\
 \hline         
    NGC~3607 & 0 &   --0.369  &    1.000  &   --0.608 \\  
    NGC~3607  &1 &   --0.183  &    0.000  &   --0.445\\  
    NGC~3607 & 2 &   --0.263  &    1.000  &   --0.434\\  
    NGC~3607  & 3 &   0.117  &    0.000  &   --0.129\\
    NGC~3818  & 0 &  --0.1947 &    0.000  &   --0.135\\
    NGC~3818  & 1 &  --0.220  &     1.000 &   --0.153\\  
    NGC~3818  & 2 &  --0.352  &     1.000 &   --0.251\\  
    NGC~3818  & 3 &  --0.211  &     0.000 &   --0.428\\ 
     ....           & ... &   .....     &   .....     &  .....  \\
\hline
\end{tabular}}
\label{table6}
\medskip
The table provides the object identification (Col.~1), the 
number of the gradient (column 2) 
($0=0 \leq  r  \leq r_{\rm e}$/16, $1 = r_{\rm e}$/$16 \leq  r  \leq r_{\rm e}$/8, 
$2 = r_{\rm e}$/$8 \leq  r  \leq r_{\rm e}$/4 and 
$3 = r_{\rm e}$/$4 \leq  r  \leq  r_{\rm e}$/2), 
and the {\it EW} of H$\beta$~emission as derived 
from the O[III] and H$\alpha$~emissions (Cols.~3 and~5
respectively). 
Column 4 gives the quality of the measure, obtained as the ratio between the
estimated emission ($F_{\rm gal} - F_{\rm templ}$) and the variance
of the spectrum in the O[III]~wavelength region, $\sigma_\lambda$. 
When the emission is lower than the variance, the quality is set to~0. 
When the emission is between~1 and~2  $\sigma_\lambda$ or larger than~2~$\sigma_\lambda$, the quality is set to~1 and~2~respectively. 
The entire table is given in electronic form.
\end{table}