\begin{table}%t4
\caption{Photometry of the outer knots.}
\label{Tphoto_R}
%\centering
\par
\begin{tabular}{rccccr}
\hline\hline
\noalign{\smallskip}
ID & radius [$\arcsec$] & $m_B$ & & $m_R$ & $(B-R)^a$ \\
\hline
\noalign{\smallskip}
1 & 0.3 & ...   & & 23.50 & $>$1.0 \\
2 & 0.3 & ...   & & 22.71 & $>$1.8 \\
3 & 0.3 & 23.47 & & 22.84 & 0.63 \\
4 & 0.3 & ...   & & 22.99 & $>$1.5 \\
5 & 0.3 & 23.77 & & 23.25 & 0.52 \\
6 & 0.3 & 23.82 & & 22.51 & 1.31 \\
7 & 0.3 & 22.75 & & 22.69 & 0.06 \\
8 & 0.3 & ...   & & 22.91 & $>$1.6 \\
9 & 0.3 & ...   & & 23.27 & $>$1.2 \\
10& 0.3 & 23.72 & & 22.99 & 0.73 \\
\noalign{\smallskip}
\hline
\end{tabular}
\begin{list}{}{}
\item[$^{{a}}$] Lower limit calculated from the
limiting magnitude in~$B$\protect ($m_B = 24.5$).
\end{list}
\end{table}