\begin{table} \caption[] {\label{tab:v636cen_age}Ages (Gyr) for the primary ($p$) and secondary ($s$) components of V636~Cen\ determined from comparison between their masses and radii and Claret models for different mixing length parameters and abundances. } \centerline { \begin{tabular}{cccccc} \hline \hline\noalign{\smallskip} & \feh\ & $l/H_{\rm p}(p)$ & $l/H_{\rm p}(s)$ & Age(p) & Age(s) \\ \noalign{\smallskip} \hline \noalign{\smallskip} 1 & --0.20 & 1.40 & 1.00 & $1.33 \pm 0.13$ & $1.37 \pm 0.55$ \\ 2 & --0.20 & 1.50 & 1.10 & $1.82 \pm 0.13$ & $3.10 \pm 0.55$ \\ 3 & --0.12 & 1.60 & 1.10 & $2.46 \pm 0.12$ & $3.25 \pm 0.53$ \\ 4 & --0.20 & 1.68 & 1.68 & $2.40 \pm 0.13$ & \\ \hline \end{tabular}} \smallskip Note: Ages in Gyr. Except for those with the solar $l/H_{\rm p} = 1.68$ (case~4), the models fit the observed effective temperatures within errors. See text for details. \end{table}