\begin{table}%t1
\caption{\label{data}HST observations of \izw.}
%\centerline
{\small
\begin{tabular}{l l c c c c }
\hline
\hline\noalign{\smallskip}
Instrument    &      Filter/    & Band &    Exposure  &    Proposal   &   Ref.$^a$  \\
    &  Grating    &  &    time [s] & ID \\
%Instrument    &      Filter/Grating    & Band &    Exptime (s)  &    Proposal   &   Reference  \\
\hline 
STIS              &   $G140M$       &\lya\ &  1764          &    GO-8302   &   1             \\
STIS              &   $G140L$        & \lya&  40~360$^b$      &    GO-9054   &   2                   \\
STIS              &   $F25SRF2$    &FUV&  5331          &    GO-9054   &   2                   \\
STIS              &   $F25QTZ$       &NUV&  5786          &    GO-9054   &   2                   \\
WFPC2         &   $F487N$        & \hb&  2500          &    GO-6536   &   3                   \\
WFPC2         &   $F658N$        & \ha&  4600        &    GO-5434   &   3                   \\
WFPC2         &   $F450W$       & B&  4600           &    GO-5434   &   3                   \\
WFPC2         &   $F675W$       & R&  2000           &    GO-5434   &   3                   \\ 
\hline  
\end{tabular}}
\par
\medskip
$^a$~References: (1) \citet{mashesse03};  (2) \citet{brown02};  (3)~\citet{cannon02}.\\
$^b$~Total integration time in the 7 slit positions.
\end{table}