\begin{table}%t2
\caption{\label{tab:knak}\textit{Knak} model parameters for the cross-calibration residuals, where a value lower than 1 means the RGS flux is higher than the pn flux.}     
%\centering
\par
\begin{tabular}{c c c c c}  
\hline\hline
\noalign{\smallskip}                
$\lambda$ ($\AA$) & 1 & 2 & 3 & Stacked \\     
\hline             
   7  & $0.97\pm0.01$& $1.00\pm0.01$& $0.98\pm0.01$& $0.99\pm0.01$ \\    
   13 & $0.98\pm0.01$& $0.97\pm0.01$& $1.01\pm0.01$& $0.98\pm0.01$\\    
   15 & $0.94\pm0.01$& $0.97\pm0.01$& $0.97\pm0.01$& $0.96\pm0.01$\\    
   19 & $0.96\pm0.01$& $0.98\pm0.01$& $0.98\pm0.01$& $0.97\pm0.01$\\    
   23 & $0.87\pm0.01$& $0.92\pm0.01$& $0.91\pm0.01$& $0.90\pm0.01$\\    
   28 & $0.92\pm0.01$& $0.94\pm0.01$& $0.91\pm0.01$& $0.92\pm0.01$\\    
   34 & $0.79\pm0.02$& $0.78\pm0.02$& $0.81\pm0.02$& $0.80\pm0.01$\\
   37 & $0.90\pm0.03$& $0.92\pm0.03$& $0.94\pm0.03$& $0.91\pm0.02$\\    
\hline
\end{tabular}\vspace*{-2mm}
\end{table}