\begin{table}%t3
\caption{Spectral properties of BDs obtained from spectral fitting. To
fit the spectra (Fig.~\ref{fig:spectra}), we used a {\tt WABS}
absorption model \citep{morrison83} combined with one or two {\tt
MEKAL} optically thin thermal plasma model \citep{mewe95} with 0.3 times
the solar elemental abundances. {\tt MEKAL} plasma models were computed
rather than
interpolated from a pre-calculated table. We used $\chi^2$ statistics with
standard weighting. Column~(4) gives the net source counts collected by
the instrument given in Col.~(3). Confidence ranges at the 68\% level
($\Delta\chi^2=1$; corresponding to $\sigma=1$ for Gaussian
statistics) are given in parentheses. The value of reduced $\chi^2$ and $\nu$,
the degrees of freedom, are indicated in Col.~(10). The emission
measures in Cols.~(8) and (9) and the X-ray luminosity in the
0.5--8~keV energy range corrected for absorption in Col.~(11) were
computed assuming a distance of 140~pc for the TMC. 
The X-ray fractional luminosity, $\eta=\log (L_{\rm X}/L_*)$, is
given in the last column. For CFHT-BD-Tau~1, the second line gives an
estimate of the quiescent X-ray luminosity derived for the light curve
fit (see Sect.~\ref{lc_analysis}).
\label{table:spectral_fit}}
%\centering
\par
\begin{tabular}{@{}llcclccccccc@{}}
\hline\hline
& \multicolumn{1}{c}{BD name} & Instr. & $N$ & \multicolumn{1}{c}{$N_{\rm H}$}          & $kT_1$ &
$kT_2$ & $EM_1$ & $EM_2$ & $\chi^2_\nu$ ($\nu$) & $L_{\rm X}$ & 
$\eta$ \\
\#& &                             &      & \multicolumn{1}{c}{$10^{21}$~cm$^{-2}$} & \multicolumn{2}{c}{keV} &
\multicolumn{2}{c}{$10^{51}$~cm$^{-3}$}  & & $10^{28}$~erg~s$^{-1}$\\
\multicolumn{1}{c}{(1)} & \multicolumn{1}{c}{(2)} & (3) & (4) &
\multicolumn{1}{c}{(5)} & (6) & (7) & (8) & (9) & (10) & (11) & (12) \\
\hline
1   & 2MASS~J0422    & pn    & 102  &  1.7 (0.9--2.8)  &   0.7 (0.6--0.8) & \dotfill        & ~2 & \dotfill  & 0.83 (07) &  02.0 & --3.5 \\
3a  & MHO~4          & EPIC  & 571  &  1.2 (0.7--1.7)  &   0.4 (0.3--0.5)  & 1.1 (1.0--1.2)  &  ~5  &  6     & 0.56 (26) &  08.3  & --3.3\\
3b  & MHO~4          & ACIS-I& 271  &  ~~0  (0--0.2)   &   0.5 (0.4--0.6)  & 1.1 (1.1--1.3)  &  ~4  &  6     & 0.85 (18) &  08.0  & --3.4\\
4a  & CFHT-Tau~5     & EPIC  & 314  &  4.9 (3.7--7.7)  &   1.5 (1.2--1.9)  & \dotfill        & 14  & \dotfill& 0.82 (13) &  11.8  & --3.4\\
5~  & CFHT-BD-Tau~1  & EPIC  & 206  &  6.0 (3.9--10.2) &   1.7 (1.1--2.6)  & \dotfill        & 17  & \dotfill& 0.59 (06) &  14.3  & --2.7\\
    &  &  &  &  &   &  &  &  &  &  07.7  & --2.9\\
8~  & CFHT-BD-Tau~4  & ACIS-I&  33  &  8.6 (5.6--13.9) &   0.5 (0.2--0.9)  & \dotfill        & 27  & \dotfill& 0.74 (3)  &  24.3  & --3.0\\
\hline
\end{tabular}
\end{table}