\begin{table}%t6
\caption{\label{tab:zpfit_results}Landolt to MegaCam color transformation slopes and airmass correction terms.}
\small%\centerline
 {
\begin{tabular}{ccccccc}
\hline
\hline
Band & Landolt            & Color & $\alpha$ & $\beta$ & $k$ & $k_{\rm Elixir}$ $^{a}$ \\
     & color index        & break &          &         &     &              \\
\hline
$g_M$  & $B-V$  & $+0.45$   & $+0.4957 \pm 0.0153$  &  $+0.4583 \pm 0.0026$  &  $-0.1830\pm 0.0017$ &  $-0.15$ \\
$r_M$  & $V-R$  & $+0.65$   & $+0.1654 \pm 0.0049$  &  $+0.2079 \pm 0.0248$  &  $-0.1346\pm 0.0017$ &  $-0.10$ \\
$i_M$  & $R-I$  & $+0.40$   & $+0.2069 \pm 0.0093$  &  $+0.1702 \pm 0.0056$  &  $-0.0467\pm 0.0017$ &  $-0.04$ \\
$z_M$  & $R-I$  & $+0.35$   & $-0.1949 \pm 0.0301$  &  $-0.4420 \pm 0.0133$  &  $-0.0585\pm 0.0034$ &  $-0.03$ \\
\hline 
\end{tabular}}
\medskip
$^{a}$ Canonical airmass coefficients reported by the Elixir pipeline in the image headers.
\end{table}