\begin{table}%t1
%\centering
\par
\caption{List of observational parameters.}
\label{tab1}
\begin{tabular}{llllll}
\hline\hline
Instrument & Date of      & Line        &  Bandwidth & Spectral   & Integration  \\
           & Observations &             &     (MHz)  & Res. (km~s$^{-1}$) &  Time (h) \\
\hline
VLA-CnB    & 2001/07/23   & $\rm{NH_3}$\ $(1,1),(2,2)$ &   3.12     &  0.6       &  0.7  \\
VLA-DnC    & 2001/10/01   & $\rm{NH_3}$\ $(3,3)$       &   3.12     &  0.3       &  1.0  \\
VLA-CnB    & 2002/09/26   & $\rm{NH_3}$\ $(1,1),(2,2)$ &   3.12     &  0.6       &  1.2     \\
VLA-CnB    & 2002/09/26   & $\rm{NH_3}$\ $(3,3)$       &   3.12     &  0.6       &   1.0    \\
VLA-CnB    & 2002/09/26   & 23~GHz      &   25       &  -         &    1.0   \\
VLA-DnC    & 2003/01/16   & $\rm{NH_3}$\ $(1,1),(2,2)$ &   3.12     &  0.3      &   0.6    \\
VLA-DnC    & 2003/01/24   & $\rm{NH_3}$\ $(3,3)$       &   3.12     &  0.6      &   1.0    \\
VLA-DnC    & 2003/02/04   & 43~GHz      &   50       &  -        &   2    \\ \hline
OVRO-E     & 2002/11/02   & HCN $(1,0) $        &   30     &  3.4      &   4.0    \\
OVRO-E     & 2002/11/02   & SiO (2--1)        &   30     &  1.7      &   4.0    \\
OVRO-E     & 2002/11/02   & HCO$^+$ (1--0)    &   7.5     &  0.84      &   4.0    \\
OVRO-E     & 2002/11/02   & 87~GHz     &   4000     &  -      &   4.0    \\
OVRO-H     & 2002/12/01   & 87~GHz     &   4000    &   -        &   2.0    \\
\hline   
\end{tabular}
\end{table}