\begin{table}%t2
%\centering
\par
\caption{The mass scaling factor of the best fit homogeneous sphere, $M_{\rm f}$ ({\it left columns}), and of the best fit porous sphere, $M_{\rm p}$ ({\it right columns}), for the absorption spectra of the Gaussian random spheres and the fractal aggregates.
\label{tab:fit parameters Mf}}
\begin{tabular}{ccccccccccccccccc}
\hline\hline
		& \multicolumn{8}{c}{Homogeneous spheres}&\multicolumn{8}{c}{Porous sphere approximation}\\
		& \multicolumn{4}{c}{\footnotesize Gaussian random spheres}&\multicolumn{4}{c}{\footnotesize Fractal aggregates}
		& \multicolumn{4}{c}{\footnotesize Gaussian random spheres}&\multicolumn{4}{c}{\footnotesize Fractal aggregates} \\
		&	$\sigma$&	$\sigma$&	$\sigma$&	$\sigma$&	$D_{\rm f}$	&	$D_{\rm f}$	&	$D_{\rm f}$	&	$D_{\rm f}$
		&	$\sigma$&	$\sigma$&	$\sigma$&	$\sigma$&	$D_{\rm f}$	&	$D_{\rm f}$	&	$D_{\rm f}$	&	$D_{\rm f}$\\
		&	$0.1$&	$0.3$&	$0.5$&	$0.7$&	$2.8$	&	$2.4$	&	$1.8$	&	$1.2$
		&	$0.1$&	$0.3$&	$0.5$&	$0.7$&	$2.8$	&	$2.4$	&	$1.8$	&	$1.2$\\
\hline
$r_V=0.4~\mu$m	&	$1.0$   &	  $1.1$   &     $1.1$	&	$1.1$   &	  $1.0$   &     $1.0$	&	$1.0$   &	  $1.0$ &	  $1.0$   &     $1.4$	&	$1.7$   &	  $1.7$   &     $1.0$	&  $1.0$	  &	  $1.0$   &     $1.0$\\
$r_V=1.0~\mu$m	&	$1.0$   &	  $1.1$   &     $1.2$	&	$1.2$   &	  $1.0$   &     $1.0$	&	$1.0$   &	  $1.0$ &	  $1.2$   &     $1.7$	&	$1.9$   &	  $1.9$   &     $1.2$	&  $1.2$	  &	  $1.4$   &     $1.6$\\
$r_V=2.0~\mu$m	&	$1.0$   &	  $1.0$   &     $1.1$	&	$1.1$   &	  $1.0$   &     $1.0$	&	$1.0$   &	  $1.0$ &	  $1.5$   &     $2.1$	&	$2.2$   &	  $2.1$   &     $1.7$	&  $1.6$	  &	  $1.7$   &     $1.8$\\
$r_V=4.0~\mu$m	&	$1.0$   &	  $0.9$   &     $0.8$	&	$0.8$   &	  $1.0$   &     $0.8$	&	$0.8$   &	  $1.0$ &	  $1.7$   &     $2.4$	&	$2.3$   &	  $2.1$   &     $1.9$	&  $1.7$	  &	  $1.7$   &     $1.8$\\
$r_V=6.0~\mu$m	&	$0.9$   &	  $0.8$   &     $0.7$	&	$0.7$   &	  $1.0$   &     $0.7$	&	$0.8$   &	  $1.0$ &	  $1.7$   &     $2.2$	&	$2.2$   &	  $1.9$   &     $1.7$	&  $1.6$	  &	  $1.8$   &     $1.9$\\
\hline
\end{tabular}
\end{table}