\begin{table}%t1
\caption{\label{tab:1}Model parameters.}              
%\centering
\small                           
\begin{tabular}{l r r}         
\hline \hline
Parameter &  Standard value & Range  \\     
\multicolumn{3}{c}{star}                                  \\
\hline 
\rstar                    &   2.1 \rsun            & \\
\mstar                    &   2.5 \msun            & \\
\teff                     &   10~000 K            & \\
\lstar                    &   40 \lsun             & \\
Distance                  &   150 pc               & \\
\hline
\multicolumn{3}{c}{disk} \\
\hline 
&& \\[-8pt]
Disk mass                 &   0.05 \msun\  (group~I), 10$^{-4}$  \msun\  (group~II) &  \\
Disk inclination angle    &   0.1 rad ($\approx$$6$\degree) &  \\
Surface mass density gradient & $-1.5$                   &  \\
Gas to dust ratio         &   100                        &  \\
Carbon abundance          &   15\%                       & 5\%, 15\%, 30\% \\
ratio large/small grains  &   50\%                       & 0\%, 50\%, 90\% \\
Crystallinity scenario    &   D, with $p = -0.65$        & $-0.30$, $-0.65$, $-1.00$, $-1.50$ \\
\hline
\end{tabular}
\end{table}