\begin{table}%t1
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\caption{\label{t1}Log of the {\it Swift}/XRT observations used in this paper.}
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\begin{tabular}{ccccc}
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\hline\hline
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Obs. & Start day & Start time & On-source & Avg. 0.3--10~keV \\
number & & (UT) & time (ks) & countrate (cts s$^{-1}$) \\
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\hline
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 \#1 & 10 Dec. 2006 & 17:48:48 & 9.9 & 0.939~$\pm$~0.014 \\
 \#2 & 07 Feb. 2008 & 15:05:24 & 2.9 & 0.369~$\pm$~0.011 \\
 \#3 & 24 Apr. 2008 & 07:49:26 & 6.9 & 1.755~$\pm$~0.031 \\
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\hline
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\end{tabular}
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\par
\end{table}