\begin{table}%t2
%\centering
\par
\caption{\label{table1}Optical counterparts to Chandra X-ray sources within the HST/ACS field of view.}   
\begin{tabular}{lrccc ccccc cc}     % 10 columns 
\hline\hline   
\noalign{\smallskip}
X-ray & \multicolumn{2}{c} {Offset From CXO position\tablefootmark{a}} & 
$U_{\rm 336}$ & $B_{\rm 439}$ & $V_{\rm 555}$ & $V_{\rm 606}$ & $I_{\rm 814}$  & 
log($L_{\rm X}$)\tablefootmark{b} & 
log($f_{\rm X}/f_{\rm O}$)\tablefootmark{c} & 
FAP\tablefootmark{d}  &
Classification\tablefootmark{e} \\  
\cline{2-3}  
 Source & $\Delta$RA ($\arcsec$) & $\Delta$Dec. ($\arcsec$) &(mag) & (mag) & (mag) & (mag) & (mag) & ${\rm erg~s^{-1}}$ & \\
\hline      
\multicolumn{12}{c}{Inside the half-mass radius} \\ 
 s01 & 0.22 & 0.49 &  \ldots\tablefootmark{f} & \ldots & \ldots & 20.85(0) & 19.94(2) & 29.85 & --2.02 & 26.06 & AB? \\
 s02 & 0.0 & --0.05 &  \ldots & \ldots & \ldots & 17.38(1) & 16.32(1) & 31.18 & --2.08 & 1.08 & AB \\
 s03a & 0.18 & --0.69 &  18.68(6) & 18.35(4) & 17.78(4) & 18.33(1) & 17.56(0) & 29.95 & --2.93 & 7.01 & AB? \\
 s03b & --0.50 & --0.29 &  19.32(9) & 19.09(4) & 18.44(4) & 18.90(1) & 18.11(0) & 29.95 & --2.70 & 10.36 & AB? \\
 s03c & --0.57  & 0.37 &  x\tablefootmark{g} & x & x & 23.8(1) & 22.81(6) & 29.95 & --0.76 & 37.35 & CV/AGN? \\
 s04 & 0.07  & --0.02 &  \ldots & \ldots & \ldots & 16.92(1) & 16.01(1) & 30.63 & --2.82 & 0.73 & AB? \\
 s05 & 0.06 & --0.05 &  \ldots & \ldots & \ldots & 22.42(5) & 21.79(0) & 31.61 & 0.37 & 11.98 & CV/AGN? \\
 s06 & 0.04 & --0.08 &  \ldots & \ldots & \ldots & 17.74(1) & 16.91(1) & 30.15 &--2.96 & 2.67 & AB? \\
 s07 & 0.33 & --0.11 &  16.26(2) & 15.16(5) & 14.30(5) & 14.86(0) & 13.89(0) & 30.31 & --3.96 & 0.25 & AB? \\
 s08 & 0.24 & --0.17 &  x & x & x & 21.48(2) & 19.96(1) & 30.78 & --0.84 & 11.31 & MSP \\
 s10 & 0.27 &  0.05 &  x & x & x & 25.25(6) & 23.4(1) & 30.37 & 0.26 & 21.96 & CV/AGN? \\
 s12 & 0.28 & --0.10 &  16.40(2) & 15.60(3) & 14.93(3) & 15.55(0) & 14.82(0) & 29.88 & --4.11 & 0.72 & AB? \\
 s14a & --0.29 & 0.54 &  x & x & x & 23.47(6) & 20.87(2) & 30.03 & --0.80 & 33.60 & F? \\
 s14b & --0.04 & --0.18 &  x & x & x & 25.8(1) & 28(2)
% \footnote{Below the 5-$\sigma$ limiting magnitude (i.e. 23.91) in the $I_{\rm 814}$ band.} 
   & 30.03 & 0.12 & 48.35 & CV/AGN? \\
 s14c & 0.18 & 0.36 &  x & x & x & 26.4(2)
% \footnote{Below the 5-$\sigma$ limiting magnitude (i.e. 25.17) in the $V_{\rm 606}$ band.}  
   & 23.46(6) & 30.03 & 0.36 & 51.13 & CV/AGN? \\
 s15 & 0.10 & 0.06 &  \ldots & \ldots & \ldots & 21.06(6) & 19.98(4) & 31.0 & --0.79 & 10.37 & CV/AB?\\
 s16 & 0.15 & --0.09 &  19.9(1) & 18.62(4) & 17.55(3) & 17.95(1) & 16.88(0) & 30.15 & --2.88 & 3.44 & F? \\
% s16b & 0.29 & -0.63 &  x & 22.0(3) & 20.3(1) & 20.12(0) & 19.28(0) & 30.15 & -2.02 & 20.80 & AB? \\
 s18 & 0.08 & --0.08 & 17.25(3) & 16.96(6) & 16.28(6) & 16.69(1) & 15.92(1) & 30.77 & --2.77 & 0.58 & AB \\
 s19a & 0.08 & --0.12 & 18.20(5) & 17.79(3) & 16.99(3) & 17.39(0) & 16.50(0) & 30.95 & --2.30 & 1.16 & AB? \\
 s19b & -0.28 & 0.10 & 19.52(9) & 18.93(4) & 18.32(4) & 18.83(1) & 18.05(1) & 30.95 & --1.73 & 4.62 & AB? \\
 s19c & 0.18 & 0.36 & x & x & x & 21.48(1) & 20.04(2) & 30.95 & -0.66 & 11.33 & AB? \\
 s20 & 0.08 & --0.07 & 16.16(2) & 15.21(3) & 14.18(4) & 14.65(0) & 13.61(0) & 31.18 & --3.17 & 0.16 & AB \\ 
 s21 & 0.17 & --0.15 & x & x & x & 27.09(9) & 26.5(3) & 29.99 & 0.61 & 42.03 & CV/AGN? \\
 s22 & 0.14 & --0.15 &  19.01(7) & 18.22(5) & 17.52(3) & 18.03(0) & 17.22(1) & 30.02 & --2.98 & 5.48 & F? \\
 s23 & 0.32 & 0.09 & 18.11(5) & 17.75(3) & 17.19(3) & 17.73(1) & 16.73(1) & 30.22 & --2.91 & 2.49 & AB? \\
 s24 & 0.21 & 0.05 &  x & 20.3(1) & 19.13(4) & 19.4(1) & 18.16(1) & 30.02 & --2.43 & 9.81 & F \\
 s25 & 0.08 & 0.06 &  x & x & x & 25.49(8) & 23.3(1) & 30.03 & 0.01 & 30.34 & CV/AGN? \\
 s26 & --0.07 & --0.08 & \ldots & 19.3(2) & 18.33(7) & 18.63(7) & 17.50(3) & 30.66 & --2.10 & 4.88 & F \\
 s27a & 0.19 & 0.17 &  16.06(2) & 15.15(4) & 14.23(4) & 14.68(0) & 13.70(0) & 30.22 & --4.12 & 0.24 & AB? \\
 s27b & --0.57 & 0.06 &  19.18(8) & 18.41(3) & 17.73(3) & 18.19(1) & 17.45(1) & 30.22 & --2.72 & 4.09 & AB? \\
 s28a & 0.35 & --0.06 &  x & \ldots & \ldots & 20.67(0) & 18.81(0) & 29.99 & --1.96 & 17.96 & F? \\
 s28b & --0.15 & 0.44 &  x & \ldots & \ldots & 20.28(1) & 19.28(1) & 29.99 & --2.11 & 16.12 & AB? \\
 s29 & 0.05 & 0.06 & 21.0(2) & \ldots & 20.9(2) & 21.44(1) & 20.76(1) & 30.85 & -0.79 & 11.20 & CV \\
\hline  
\multicolumn{12}{c}{Outside the half-mass radius} \\ 
 s41 & 0.13 & --0.12 &  \ldots & \ldots & \ldots & 21.53(1) & 20.77(1) & 30.69 & --0.91 & 14.47 & CV/AGN? \\
 s49a & --0.24 & 0.09 & \ldots & 19.87(7) & 18.49(3) & 18.74(1) & 16.72(1) & 30.13 & --2.59 & 9.43 & F \\
 s49b & --0.31 & --0.38 & \ldots & x & x & 20.93(2) & 18.35(1) & 30.12 & --1.71 & 21.64 & F \\
 s54a & 0.68 & 0.20 & \dots & \dots & \ldots & 15.36(0) & 14.46(0) & 30.62 & --3.45 & 
   0.65\tablefootmark{h} & AB? \\
 s54b & --0.23 & --0.05 & \dots & \ldots & \ldots & 21.46(1) & 20.72(1) & 30.62 & --1.01 & 19.76$^{h}$ & CV/AGN? \\  
\par
\hline         
\end{tabular}
\tablefoot {
\tablefoottext{a}{The position offsets of sources detected in 
the $V_{\rm 606}$ band are given relative to their Chandra positions (see Elsner et al. 2008 for details).}
\tablefoottext{b}{$L_{\rm X}$: unabsorbed X-ray luminosity in the energy band is 0.5--2.5~keV 
\citep[see Table 5 of][]{2008elsner}.}
\tablefoottext{c} {Ratio of X-ray to optical ($V_{\rm 606}$) flux is computed by using 
log($f_{\rm X}/f_{\rm O}$) = log~$f_{\rm X} + 0.4V_{\rm 606} + 5.07$; $f_{\rm X}$ is derived in the 
0.5--2.5~keV band.}
\tablefoottext{d} {FAP: false alarm probability (\%). The probability of a chance coincidence in \% is calculated from 
$P_{\rm coinc}=N(<m)\pi r_{95}^2/A_{\rm search}$ \citep[see Sect.~6.1 of ][]{2008elsner}. The search area, 
$A_{\rm search}$, is the central region of M~71 with the radius of $2\arcmin$ \citep[see][]{2008anderson} and the 
considered magnitude, m, is $V_{\rm 606}$ band magnitude. }
\tablefoottext{e} {MSP: millisecond pulsar; CV: cataclysmic variable; AB: X-ray active binary; AGN: active 
galactic nucleus; F: foreground source; ?: all cases where we are not certain about the nature of the X-ray source.}
\tablefoottext{f}{Sources lying outside the field-of-view of the WFPC2 chips do not have 
 F336W, F439W or F555W data.}
 \tablefoottext{g}{Under detection limit.}
 \tablefoottext{h} {Since the source is outside the searching region of the $2'$-radius central 
   circle \citep{2008anderson}, the $A_{\rm search}$ for the probability of a chance coincidence is calculated with 
   the HST/ACS field of view, i.e. $202\arcsec \times 202\arcsec$.}}
   \vspace*{-4mm}
\end{table}