\begin{table}%t5
%\centering
\par
\caption{Characteristics of the various dust components used in the fitting procedure
(see Sect.~\ref{sec:t2_fs:compositional_fits}). The chemical formulae and
assumed grain shapes have been indicated in the second and third column. In the fourth
column, we give references for the refractive index data used.\label{tab:t2_fs:template data}}
\begin{tabular}{llll}
\hline\hline
Dust component & Chemical formula & Shape & Reference\\
\hline
Amorphous olivine	&Mg$_{2x}$Fe$_{2-2x}$SiO$_4$  &Homogeneous spheres &    \citet{Dorschner1995} \\
Amorphous pyroxene	&Mg$_{x}$Fe$_{1-x}$SiO$_3$    &Homogeneous spheres &   \citet{Dorschner1995} \\
Crystalline forsterite	&Mg$_{2}$SiO$_4$  	      &Irregular (DHS)	   &   \citet{Servoin1973} \\
Crystalline enstatite	&MgSiO$_3$		      &Irregular (DHS)	   &   \citet{Jaeger1998} \\
Amorphous silica 	&SiO$_2$ 		      &Irregular (DHS)	   &   \citet{1960PhRv..121.1324S} \\
\hline   
\end{tabular}
\end{table}