\begin{table}%t3
\caption{\label{tab:featextent}Summary of the radial spatial extent of the PAH~feature (half-width at half-maximum).}
\small%\centerline
{
\begin{tabular}{lllllllll}
\hline
\hline
Source 		&   \multicolumn{2}{c}{3.3~\micron} & \multicolumn{2}{c}{8.6~\micron} & \multicolumn{2}{c}{11.2~\micron} & \multicolumn{2}{c}{12.7~\micron}  \\
\hline            
\multicolumn{9}{l}{PAH~detected and spatially resolved} \\
HD~100546  & $0.12''$ & 12~AU & -- & --   & -- & --   & -- & -\\
TY~CrA          & $0.39''$ & 55~AU & --    & --    & -- & --    & --    & -\\
WL~16           & -- & -- & $0.43''$ & 54~AU & 0.49$''$ & 61~AU & 0.46$''$ & 58~AU \\
IRS~48          & $0.11''$ & 14~AU & $0.25''$ & $31$~AU   & $0.32''$ & $40$~AU  & $0.33''$& $41$~AU \\
\hline
\multicolumn{9}{l}{PAH~detected but spatially unresolved} \\
HD~98922        & $\leq$$ 0.24''$ & $\leq$130~AU$^{a}$ & $\leq$$0.17''$ & $\leq$$ 92$~AU & $\leq$$ 0.15''$ & $\leq$$ 81$~AU  & -- & -- \\
HD~101412       & $\leq$$ 0.24''$  & $\leq$38~AU & $\leq$$ 0.16''$ & $\leq$26~AU & $\leq$$0.15''$ & $\leq$ 24~AU & -- & --\\
Em* SR~21A          & $\leq$$ 0.33''$ & $\leq$41~AU &$\leq$$0.16''$ & $\leq$20~AU &$\leq$$0.17''$&  $\leq$21~AU & $\leq $$0.15''$ & $\leq$19~AU\\
T~Cha           & $\leq$$ 0.34''$ & $\leq$22~AU & --    & --  & $\leq$$ 0.19''$ & $\leq$13~AU & -- & -- \\
EC~82           & -- & -- & $\leq$$0.18''$    & $\leq$47~AU & $\leq$$ 0.23''$    & $\leq$60~AU & -- & -\\
\hline		   
\end{tabular}}
\smallskip
 $^{a}$  Uncertain distance to source.
\end{table}