\begin{table}%t2
\caption{\label{tavola2}Main characteristics of the three selected short-event light curves; $d$~is the projected distance from the centre of M~31.}
%\centering
\par
\begin{tabular}{cccc}
\hline\hline
& C3 & C4 & C5\\
\hline
$\alpha$ (J2000) & $\rm 00^h42^m12.5^s$ & $\rm 00^h42^m25.6^s$ & $\rm 00^h41^m52.8^s$ \\
$\delta$ (J2000) & $41^\circ21'30''$ & $41^\circ 26' 27''$ & $41^\circ 17' 18''$ \\
$d$ & $8'01''$ & $10'53''$ & $9'45''$ \\
$\chi^2/\textrm{d.o.f.}$ & 2.90 & 2.32 & 2.47 \\
${\rm d}w_R$ & 2.48 & 2.01 & 1.78 \\
${\rm d}w_I$ & 1.62 & 2.23 & 1.92 \\
$t_{1/2}$ (days) & $16 \pm 2$ & $13 \pm 2$ & $14\pm 2$ \\
$R_{\rm max}$ & $21.0 \pm 0.1$ & $21.3 \pm 0.1$ & $21.8\pm 0.1$ \\
$R-I$ & $2.2\pm 0.2$ & $1.1 \pm 0.2$ & $0.5\pm 0.2$\\
INT data &  inconclusive & inconclusive & no extension\\
\hline
\end{tabular}
\end{table}