\begin{table}%t3
%%%\centering


\par
\caption{\label{hard} PN spectral fits for \Xvingt in the hard energy band $2{-}8$~keV and galactic absorption.}
\begin{tabular}{lcccc}
 \hline \hline
\multicolumn{1}{c}{Model} & \multicolumn{1}{c}{$\Gamma $} &
\multicolumn{1}{c}{$E$} &
\multicolumn{1}{c}{$\sigma $/$\tau $} &
 \multicolumn{1}{c}{$\chi^2_{\rm red}$/d.o.f.} \\
\multicolumn{1}{c}{  } & \multicolumn{1}{c}{ } & \multicolumn{1}{c}{(1)} &
\multicolumn{1}{c}{(2) } &
 \multicolumn{1}{c}{}\\
\noalign{\smallskip} \hline \noalign{\smallskip}
pow & 1.44$~\pm~$0.04 &  &   & 0.87/196\\
pow + Gauss &
   1.44$~\pm~$0.05 & 4.96$~\pm~$0.06 &  (0.01) & 0.84/194\\
pow + edge &  1.40$~\pm~$0.07 &  5.10$~\pm~$0.20 &  
0.10~$\pm$~0.10 & 0.85/194\\
\noalign{\smallskip}\hline
\end{tabular}
\begin{flushleft}
 The errors given are at the 90\% level.\\
$^{(1)}$ Line energy in~keV; ~ the normalization of the line  is 
     $3.02\pm 2.57 \times$ $ 10^{-6}$ ph/keV/cm$^2$/s.\\
$^{(2)}$ Line width ($\sigma $) or depth of the absorption edge ($\tau $) in~keV.\\
\end{flushleft}
\end{table}