\begin{table}%t4
\caption{Mean values of \AMM\ core samples.\label{tab:nh3_lowmass}}
%\centerline
{
\begin{tabular}{rccccc}
\hline
\hline
Sample & \dlabel{{\it FWHM} (\kms)} & \dlabel{$T_{\rm kin}$(K)} & \dlabel{size(pc)}& \dlabel{$M_{\rm NH_3}$ ($M_{\odot}$)}& \dlabel{$\Sigma$} \\
\hline
Taurus&0.33  & 10& 0.06 & 1.1 & 0.08 \\
Perseus&0.55  &13 & 0.12 &  9 & 0.16 \\
Orion&1.12 & 17& 0.15 & 21 & 0.24 \\
IRDC cores& 1.7 &15& 0.57& 492 & 0.40 \\
\hline
\end{tabular}}
\par
\smallskip
Notes: Columns are the source sample, the mean {\it FWHM} of the \AMM\ (1,~1)
line, kinetic temperature, size of the core, mass as determined from
\AMM\ assuming a fractional abundance of \AMM\ relative to $\rm H_2$
and the mean surface density.  The mean values for dense cores in
Taurus, Perseus and Orion have been taken from \citet{ladd1994:nh3_perseus}.
\par
\end{table}