\begin{table}%T7
\caption{Final list of X-ray sources identified with stars attributed
to cluster NGC~2451~A, yielding 
Williams number (W~\#), mean X-ray positions (J2000), offset ($\Delta$) between
X-ray and optical positions in arcsec, $V$ magnitudes, measured $B-V$ and 
de-reddened $(B-V)_0$ colour indices.
An asterisk indicates values from the literature used for bright stars that
are overexposed in our images. Where
significant variations in the X-ray flux have been found an X is written
into the Var column. Spectral types are given in parentheses if estimated
from the colour index. The last column gives a common star designation.\label{X2451A}}
%%%%\centerline


\par
{{\footnotesize
\begin{tabular}{rrccrrrrccccc}
\hline\hline
\noalign{\smallskip}
X~\#&W~\#&RA&DEC&$\Delta$&$V$&$B-V$&$(B-V)_{0}$&Var&log~$L_{\rm x}$&
log~$\frac{L_{\rm x}}{L_{\rm bol}}$&Spec.&Notes \\
\noalign{\smallskip}
\hline
\noalign{\smallskip}
  X3&   & 7 46 09 & --37 24 45&48&10.66*&0.52* &0.51 & &28.88&--4.92&(F8V)&\\ 
 X11&256& 7 45 28 & --37 35 41& 9&6.91* &--0.05*&--0.06& &29.38&--6.01&B9V&HD 63079\\
 X22&   & 7 46 54 & --37 43 07&10&16.72 &1.52  &1.51 & &29.27&--2.78&(M2V)&\\
 X30&   & 7 44 16 & --37 45 59&34&13.15 &1.06  &1.05 & &29.04&--3.99&(K4V)&\\
 X31& 68& 7 45 38 & --37 46 39& 5&11.46 &0.65  &0.64 &X&29.91&--3.65&(G3V)&CD--37 3870\\
 X32&   & 7 43 55 & --37 46 37& 6&16.42 &1.52  &1.51 & &29.12&--3.05&(M2V)&\\
 X40&   & 7 45 05 & --37 48 07& 1&15.49 &1.38  &1.37 & &28.99&--3.31&(K8V)&\\
 X59&   & 7 46 29 & --37 52 37&16&17.36 &1.54  &1.53 & &28.99&--2.82&(M2V)&\\
 X61&251& 7 45 05 & --37 53 16& 1&6.53* &--0.11*&--0.12& &--&--&B3IV&HD 62991\\
 X63& 15& 7 43 49 & --37 53 46& 1&10.57*&0.52* &0.51 & &29.19&--4.68&(F8V)&CD--37 3823\\
 X72&   & 7 45 16 & --37 54 39& 2&12.38 &0.76  &0.75 &X&29.74&--3.45&(G8V)&\\
 X80&267& 7 46 10 & --37 56 01& 4&5.87* &--0.09*&--0.10& &29.38&--6.54&B7V&HD 63215\\
 X83&   & 7 45 05 & --37 56 35& 2&15.42 &1.34  &1.33 & &28.94&--3.34&(K8V)&\\
 X84&246& 7 44 34 & --37 56 36& 3&5.89* &--0.10*&--0.11& &--&--&B7V&HD 62893\\
 X97&   & 7 47 42 & --37 58 43&33&11.86*&0.73* &0.72 & &29.20&--4.22&(G8V)&\\
X102&   & 7 44 07 & --37 59 24& 1&16.43 &1.51  &1.50 & &29.30&--2.85&(M1V)&\\
X103&244& 7 44 28 & --37 59 16& 1&8.62* &0.12* &0.11 & &29.55&--5.06&A3V&HD 62876\\
X106&   & 7 43 54 & --38 00 03& 1&12.30 &0.81  &0.80 & &29.46&--3.77&(K0V)&\\
X108&   & 7 46 25 & --38 00 09&20&14.57 &1.37  &1.36 & &28.82&--3.88&(K8V)&\\
X109& 46& 7 44 56 & --38 00 18& 4&9.80* &0.54* &0.53 & &28.80&--5.29&(F8V)&CD--37 3853\\
X114&   & 7 46 24 & --38 01 04&11&12.71 &0.89  &0.88 & &28.52&--4.65&(K1V)&\\
X116& 50& 7 45 02 & --38 02 24& 4&10.01 &0.42  &0.41 & &28.82&--5.22&(F5V)&CD--37 3859\\
X117&   & 7 48 07 & --38 02 10& 9&12.54 &0.86  &0.85 & &30.06&--3.09&(K1V)&\\
X128&   & 7 45 05 & --38 04 29& 0&17.67 &1.54  &1.53 &X&28.94&--2.79&(M2V)&\\
X132& 47& 7 44 60 & --38 05 43& 5&8.30* &0.15* &0.14 & &29.77&--4.96&A3V&HD 62974\\
X134&  3& 7 42 46 & --38 05 54&23&10.84*&0.56* &0.55 &X&29.42&--4.34&(F8V)&CPD--37 1499\\
X142& 89& 7 46 35 & --38 06 43& 4&10.01*&0.33* &0.32 & &29.69&--4.37&(F0V)&CD--37 3897\\
X144&   & 7 43 51 & --38 07 06& 5&15.92 &1.49  &1.48 & &29.36&--2.93&(M1V)&\\
X149& 94& 7 46 49 & --38 08 50&15&9.46* &0.43* &0.42 & &29.27&--5.04&(F5V)&CD--37 3902\\
X151&   & 7 43 06 & --38 09 19& 3&15.34 &1.39  &1.38 &X&29.65&--2.73&(M0V)&\\
X152&   & 7 45 22 & --38 09 51&39&13.21 &0.98  &0.97 & &28.52&--4.49&(K3V)&\\
X156& 57& 7 45 15 & --38 11 50& 3&11.00 &0.56  &0.55 &X&30.31&--3.38&(F8V)&CD--37 3862\\
X157&233& 7 43 43 & --38 12 14&10&6.35* &--0.09*&--0.10& &29.19&--6.51&B9Vsp&HD 62712\\
X160&   & 7 47 04 & --38 12 31&10&16.32 &1.56  &1.55 & &29.38&--2.93&(M3V)&\\
X173&   & 7 43 52 & --38 16 20&20&14.89 &1.50  &1.49 & &29.58&--3.15&(M1V)&\\
X177&   & 7 48 15 & --38 22 35&48&11.29 &0.61  &0.60 & &30.27&--3.32&(G0V)&\\
X181&   & 7 43 58 & --38 27 48&25&13.55 &1.11  &1.10 &X&29.61&--3.21&(K4V)&\\
X187&   & 7 45 50 & --38 33 55&38&12.58 &0.84  &0.83 & &29.81&--3.31&(K0V)&\\
X188&   & 7 44 25 & --38 35 49&22&10.95*&0.61* &0.60 &X&30.09&--3.64&(G0V)&\\
\hline
\end{tabular}}}
\par
\medskip
Notes on individual objects:\\
X61: HRI detection only; UV contamination assumed.\\
X63: probably non-member due to lower metallicity (H\"unsch et~al.~\cite{MH03}).\\
X84: HRI detection only; UV contamination assumed.\\
X109: possibly foreground star; soft X-ray source, slightly above 
the main sequence, lower Li abundance (H\"unsch et~al. \cite{MH03}).\\
X128: flare star; X-ray parameters given for quiescent state.\\
X151: flare star; X-ray parameters given for quiescent state.\\
X156: close visual binary, not resolved in X-rays.\\
X177: close visual binary, not resolved in X-rays.
\end{table}