\begin{table}%t5
%\centering
\par
\caption {\label{Xflux}The soft (0.5--2.0~keV) X-ray flux of Cyg~OB2~\#5 as a function of time.}
\begin{tabular}{c c c c}
\hline\hline
JD-2~400~000 & $\phi$ & Instrument & $f_{\rm X}^{\rm obs}$ \\
             &      &            & erg~cm$^{-2}$~s$^{-1}$ \\
\hline
%\vspace*{-3mm}\\
$48368.064 \pm 0.137$ & $0.570 \pm 0.021$ & PSPC         & $1.59 \times 10^{-12}$ \\
%\vspace*{-3mm}\\
$49106.963 \pm 0.466$ & $0.558 \pm 0.071$ & SIS0 and SIS1 & $1.66 \times 10^{-12}$ \\
%\vspace*{-3mm}\\
$49107.121 \pm 0.087$ & $0.582 \pm 0.013$ & PSPC         & $1.48 \times 10^{-12}$ \\
%\vspace*{-3mm}\\
$49109.234 \pm 0.058$ & $0.902 \pm 0.009$ & PSPC         & $1.63 \times 10^{-12}$ \\
%\vspace*{-3mm}\\
$49110.131 \pm 0.203$ & $0.038 \pm 0.031$ & PSPC         & $1.62 \times 10^{-12}$ \\
%\vspace*{-3mm}\\
$49111.230 \pm 0.376$ & $0.205 \pm 0.057$ & PSPC         & $1.64 \times 10^{-12}$ \\
%\vspace*{-3mm}\\
$53308.579 \pm 0.122$ & $0.354 \pm 0.018$ & EPIC         & $1.39 \times 10^{-12}$ \\
%\vspace*{-3mm}\\
$53318.558 \pm 0.133$ & $0.866 \pm 0.020$ & EPIC         & $1.57 \times 10^{-12}$ \\
%\vspace*{-3mm}\\
$53328.543 \pm 0.145$ & $0.380 \pm 0.022$ & EPIC         & $1.46 \times 10^{-12}$ \\
%\vspace*{-3mm}\\
$53338.506 \pm 0.133$ & $0.890 \pm 0.020$ & EPIC         & $1.51 \times 10^{-12}$ \\
%\vspace*{-3mm}\\
$54220.366 \pm 0.167$ & $0.543 \pm 0.025$ & EPIC         & $1.98 \times 10^{-12}$ \\
%\vspace*{-3mm}\\
$54224.180 \pm 0.173$ & $0.121 \pm 0.026$ & EPIC         & $2.44 \times 10^{-12}$ \\
\hline
\end{tabular}
\end{table}