\begin{table}%t5
\caption{\label{tab:bestpar}Best-fit parameters of Sirius~B and HZ~43A.}
\par
%\centerline
{ \small
\begin{tabular}{lc|ccc|ccc}
\hline\hline
Parameter                            &Search range & Best value$^a$ & Median value$^b$ & Allowed range$^c$ & Best value$^a$ & Median value$^b$ & Allowed range$^c$  \\
&&\multicolumn{3}{c|}{Short cut-off Lyman pseudocontinuum} & \multicolumn{3}{c}{Long cut-off Lyman pseudocontinuum} \\
&&\multicolumn{3}{c|}{(model 1)                          } & \multicolumn{3}{c}{(model 2)                         } \\
\hline
HZ~43A:                              &             &            &              &               &            &              &                \\
$T_{{\rm eff}}$ (K)               &47~000$-$57~000& 51~660      & 51~660        & 51~420$-$51~880 & 51~530      & 51~460        & 51~240$-$51~690  \\
$\log g$ (m~s$^{-2}$)               &5.8$-$6.3    & 6.064      & 6.065        & 6.031$-$6.102 & 5.893      & 5.913        & 5.872$-$5.941  \\
H-layer mass ($10^{-11}$~\Msun)      &0.02$-\infty$& 5          & 0.4          & 0.3$-\infty$  & 11         & 10           & 0.25$-\infty$  \\
ISM \ion{H}{i}  ($10^{22}$~m$^{-2}$) & 0.73$-$0.97 & 0.85       & 0.85         & 0.81$-$0.90   & 0.85       & 0.84         & 0.79$-$0.91    \\
ISM \ion{He}{i} ($10^{22}$~m$^{-2}$) &0.053$-$0.061& 0.057      & 0.058        & 0.055$-$0.059 & 0.057      & 0.055        & 0.055$-$0.058  \\
ISM \ion{He}{ii} ($10^{22}$~m$^{-2}$)&0.015$-$0.063& 0.038      & 0.042        & 0.029$-$0.047 & 0.038      & 0.042        & 0.029$-$0.048  \\
$f_d=R^2/d^2$ ($10^{-23}$)           &             & 3.037      & 3.037        & 3.025$-$3.050 & 3.038      & 3.041        & 3.031$-$3.053  \\
Grav. redshift (km~s$^{-1}$)        & 10$-$50     &   45       &   45         & 41$-$50       & 30.0       & 31.5         & 28.6$-$33.6    \\
\hline
Sirius~B:                            &             &            &              &               &            &              &                \\
$T_{{\rm eff}}$ (K)               &24~000$-$26~000& 25~360      & 25~360        & 25~320$-$25~410 & 24~970      & 24~980        & 24~940$-$25~010  \\
$\log g$ (log m~s$^{-2}$)           & 6.52$-$6.72 & 6.628      & 6.626        &  6.624$-$6.631& 6.624      & 6.623        &  6.621$-$6.627 \\
He/H ratio ($\times 10^{-6}$)        & 0$-$6       & 0          & 0.2          & 0$-$0.5       & 0          & 0.6          & 0$-$1.0        \\
ISM \ion{H}{i}  ($10^{22}$~m$^{-2}$) & 0.36$-$0.80 & 0.58       & 0.57         & 0.50$-$0.66   & 0.59       & 0.59         & 0.50$-$0.69    \\
ISM \ion{H}{i}/\ion{He}{i}           & 10.0$-$15.6 & 12.8       & 13.0         & 11.8$-$14.0   & 12.8       & 12.4         & 11.9$-$13.9    \\
ISM \ion{He}{ii}/He                  & 0.19$-$0.35 & 0.27       & 0.27         & 0.24$-$0.30   & 0.27       & 0.25         & 0.24$-$0.30    \\
$f_d=R^2/d^2$ ($10^{-21}$)           &             & 4.91       & 4.93         & 4.87$-$4.95   & 4.95       & 4.97         &  4.92$-$4.99   \\
\hline
\end{tabular}}
\par
\smallskip
$^{a}$ Best values (minimum $\chi^2$).
$^{b}$ Corresponding to the parameters of the
spectrum closest to the median of all allowed spectra.
$^{c}$ Corresponding to $\Delta\chi^2=2$ (see text for discussion). 
\end{table}