\begin{table}%T1
\caption{\label{tbl:modeldefs}Spectral model definitions.}
\small
%%\centering
\par
\begin{tabular}{cl}
\hline\hline
Parameter & Definition \\
\hline
$P_1$ & Power law representing the residual \\
      & SP contamination. \\
$G_1$, $G_2$ & Gaussians representing the Al~K$\alpha$ \\
      & and Si~K$\alpha$ FX lines. \\
$C_1$, $C_2$ & Constants representing the different \\
      & solid angles of the extraction \\
      & annuli and calibration offsets between \\
      & the two detectors. \\
$A_1$ & CXB LHB thermal component. \\
$A_2$ & CXB cooler halo thermal component. \\ 
$A_3$ & CXB hotter halo thermal component. \\ 
$P_2$ & CXB extragalactic power law  \\
      & component. \\
$N_{\rm Hg}$ & Column density of Galactic hydrogen. \\
$AC$  & Cluster thermal component. \\
$N_{\rm Hc}$ & Column density foreground to the \\ 
         & cluster, includes both Galactic \\ 
         & hydrogen and material associated \\
         & with the cluster. \\
\hline
\end{tabular}
\end{table}