\begin{table}%t6
%\centering
\par
\caption{\label{tab_fvar4nights}Mean Flux and the fractional rms $F_{\rm var}$ night by night for MJD~53944--53947.}
\begin{tabular}{c c c c c}   
\hline \hline \noalign{\smallskip}              
MJD &Duration  & Energy& $\overline{\Phi}$ & $F_{\rm var}$ \\
 & (min) & (TeV) & (10$^{-10}$ \percmsqrs) &  \\
\hline                        
53944 & 88  & & & \\
 & & all  & 15.44 $\pm$ 0.87 &  0.56 $\pm$ 0.01            \\
 & & 0.2--0.5&  13.28 $\pm$ 0.85  &  0.55 $\pm$ 0.01            \\
 & & 0.5--5.0&  1.94 $\pm$ 0.24  & 0.61 $\pm$ 0.03       \\
\hline
53945 & 244 & & & \\
 & & all  & 2.40 $\pm$ 0.41 &  0.67 $\pm$ 0.03            \\
 & & 0.2--0.5&  2.35 $\pm$ 0.42  &  0.64 $\pm$ 0.03            \\
 & & 0.5--5.0&  0.34 $\pm$ 0.12  &     --     \\
\hline
53946 & 252 & & & \\
 & & all  & 11.39 $\pm$ 0.80 &  0.35 $\pm$ 0.01           \\
 & & 0.2--0.5&  10.02 $\pm$ 0.79  &  0.33 $\pm$ 0.01            \\
 & & 0.5--5.0&  1.39 $\pm$ 0.20  &  0.43 $\pm$ 0.02      \\
\hline
53947 & 252 & & & \\
 & & all  & 4.26 $\pm$ 0.52 &  0.22 $\pm$ 0.02           \\
 & & 0.2--0.5&  4.02 $\pm$ 0.52  &  0.22 $\pm$ 0.02            \\
 & & 0.5--5.0&  0.37 $\pm$ 0.11  &  0.13 $\pm$ 0.09      \\
\hline
\end{tabular}
\tablefoot {The values refers to light curves with 4~min bins and respectively in three energy bands: $>$0.2~TeV, 0.2$-$0.5~TeV, 0.5$-$5.0~TeV. Since a significant fraction (${\approx}40\%$) of the points in the light curve of MJD~53945 in the energy band 0.5$-$5.0~TeV have a significance of less than 2~standard deviations, its~$F_{\rm var}$ is not estimated.}
\end{table}