\begin{table}%t4
 \caption{\label{tab4}Model parameters.}
%\centering
\par
\begin{tabular}{c c c c}
 \hline\hline
Parameter & Symbol & Type & Value(s)\\
\hline
Inclination & $i$ &variable &0, 15, 30, 45, 60, 75, 90$\degr$ \\
Outer radius & $R{\rm _{out}}$ &variable &50, 10, 200, 400, 800~AU \\
Inner radius & $R{\rm _{in}}$ &fixed &0.4~AU \\
Disc mass (gas+dust) & $M_{\rm disc}$ &fixed &0.01~$M_{\odot}$ (test calculations also done, up to 0.07) \\
Surface density at 100~AU &$\Sigma_{\rm 100}$ &variable &calculated based on choice of $R_{\rm out}$ \\
Surface density exponent & $p$  &fixed &1 \\
Temperature at 100~AU & $T_{100}$  &fixed &30, 60~K \\
Temperature exponent & $q$  &fixed &0.5 \\
Scale height at 100~AU & $h_{100}$  &fixed &10$^{12}$~m \\
Scale height exponent & $y$  &fixed &--1 \\
Turbulent equivalent line width & $dV$  &fixed &0.16~km~s$^{-1}$\\
Stellar mass & $M_{\rm star}$ & fixed & 2.0~$M_{\odot}$  \\
Dust opacity & $\kappa$ & fixed & 2~cm$^2$g$^{-1}$ \\
\hline
\end{tabular} 
\end{table}