\begin{table}%t2 \caption{\label{t2}Apsidal motion elements of MY~Cyg.} %\centering \small \begin{tabular}{cccc} \hline\hline Parameter & Unit & T09 & This paper \\ \hline $T_0$ & HJD & -- & 2~441~585.6334 (3) \\ $P_{\rm s}$ & days & 4.005186427 & 4.00518779 (12) \\ $P_{\rm a}$ & days & -- & 4.00521882 (12) \\ $e$ & -- & 0.010 (1) & 0.0094 (2) \\ $\dot{\omega}$ & deg $\:\rm{cycle^{-1}}$ & -- & 0.0028 (3) \\ $\dot{\omega}$ & deg $\:\rm{yr^{-1}}$ & --0.21 (7) & 0.25 (3) \\ $\omega_0$ & deg & 69.6 (2.4) & 291.7 (0.4) \\ $U$ & years & 1700 & 1420 (160) \\ \hline \end{tabular} \end{table}