\begin{table}%t3
%\centering
\par
\caption{Monte Carlo model fits.
\label{tbl-3}}
\begin{tabular}{lccc}
\hline\hline
\noalign{\smallskip}
\mbox{Parameter} & \mbox{L1498}  & \mbox{L1517B} & \mbox{Note}  \\
\noalign{\smallskip}
\hline
\noalign{\smallskip}
\multicolumn{1}{c} {\mbox{Core}}\\
\hline
\noalign{\smallskip}
$r_{\rm max}$ \mbox{~~(cm)} & $4\times 10^{17}$ & $4\times 10^{17}$ & \\
$V_{\rm LSR}$ \mbox{~~(km s$^{-1}$)} & 7.8 & 5.8 & \\
${\rm d}V/{\rm d}r\vert_{\rm in}$ \mbox{~~(km s$^{-1}$~pc$^{-1}$)} & 0 & 0 & (1) \\
${\rm d}V/{\rm d}r\vert_{\rm out}$ \mbox{~~(km s$^{-1}$~pc$^{-1}$)}  & $-$0.5 & 2.0 & (1) \\
$r_{\rm br}$ \mbox{~~(cm)} & $1.75 \times 10^{17}$ & $1.5 \times 10^{17}$ & (1) \\
$\Delta V_{\rm NT}$ \mbox{~~(km s$^{-1}$)} & 0.125 & 0.125 & \\
$T_k$ \mbox{~~(K)} & 10 & 9.5 & (2) \\
\noalign{\smallskip}
\hline
\multicolumn{1}{c} {\mbox{Envelope}}\\
\hline
\noalign{\smallskip}
$r_{\rm max}$ \mbox{~~(cm)} & $8\times 10^{17}$ & $8\times 10^{17}$ & \\
$V_{\rm LSR}$ \mbox{~~(km s$^{-1}$)} & 7.45 & 5.8 & \\
$\Delta V_{\rm NT}$ \mbox{~~(km s$^{-1}$)} & 0.625 & 0.500 & \\
\noalign{\smallskip}
\hline
\multicolumn{1}{c} {\mbox{Molecular abundances}}\\
\hline
\noalign{\smallskip}
$X_0$(\mbox{NH$_3$}) & $1.4 \times 10^{-8}$ & $1.7 \times 10^{-8}$ & (3) \\
$\beta$ & 3 & 1 & (4) \\
$X_0$(\mbox{N$_2$H$^+$}) & $1.7 \times 10^{-10}$ & $1.5 \times 10^{-10}$ & (4) \\   
$X_0$(\mbox{C$^{18}$O}) & $0.5 \times 10^{-7}$ & $1.5 \times 10^{-7}$ & (5) \\   
$r_{\rm hole}$(\mbox{C$^{18}$O}) \mbox{~~(cm)} & $1.5 \times 10^{17}$ 
& $1.75 \times 10^{17}$ & (5) \\
$X_0(\mbox{CS})$ & $3 \times 10^{-9}$ & $3 \times 10^{-9}$ & (5) \\   
$r_{\rm hole}$(\mbox{CS}) \mbox{~~(cm)} & $1.0 \times 10^{17}$ &$ 1.15 \times 10^{17}$ 
& (5) \\
\hline
\end{tabular}
\begin{list}{}{}
     \item[(1)] ${\rm d}V/{\rm d}r = {\rm d}V/{\rm d}r\vert_{\rm in}$ if $r<r_{\rm br}$ and 
     ${\rm d}V/{\rm d}r = {\rm d}V/{\rm d}r\vert_{\rm out}$ if $r>r_{\rm br}$.
     \item[(2)] Constant for all $r$.
     \item[(3)] Para-$X$(NH$_3$) = $X_0$(NH$_3$) $(n(r)/n_0)^\beta$ with 
     $10^{-9}$ threshold.
     \item[(4)] Constant in L1517B. For L1498, abundance drops by factor 3 
     at $r=1.8\times 10^{17}$~cm.
     \item[(5)] $X = X_0$ for $r>r_{\rm hole}$ and $X = 0$ for $r<r_{\rm hole}$.
\end{list}
\end{table}