\begin{table}%t4
\caption{\label{tab:nuclradii}Properties of the nuclei of the comets.}
\small%\centerline
{
\begin{tabular}{lrrrrr}
\hline\hline 
  Comet  &  $R_{\rm app}$ (mag)   &
   $r_{\rm n}$ (km)  &  $(V-R)$  &   $(B-V)$   &
  $(R-I)$  \\ 
\noalign{\smallskip}\hline 
{\it Solar colors}: & & & 0.35 & 0.65 & 0.28 \\
\noalign{\smallskip}
  4P/Faye           & 20.12~$\pm$~0.03 & 1.77~$\pm$~0.04 &
   0.45~$\pm$~0.04 & -- & -- \\ 
 10P/Tempel 2       & 14.77~$\pm$~0.03 &    5.98~$\pm$~0.04$^*$ & 
   0.49~$\pm$~0.03 & 0.80~$\pm$~0.02 & 0.52~$\pm$~0.03 \\ 
 17P/Holmes         & 20.61~$\pm$~0.04 & 1.71~$\pm$~0.07 & 
   0.56~$\pm$~0.02 & -- & -- \\ 
 37P/Forbes         & 20.83~$\pm$~0.04 & 0.81~$\pm$~0.04 &
   0.29~$\pm$~0.03 & -- & 0.66~$\pm$~0.06 \\ 
 44P/Reinmuth 2     & 19.83~$\pm$~0.05 & 1.61~$\pm$~0.07 & 
   0.62~$\pm$~0.08 & -- & -- \\
 50P/Arend          & 20.58~$\pm$~0.04 & 0.95~$\pm$~0.03 & 
   0.81~$\pm$~0.10 & -- & 0.26~$\pm$~0.09 \\ 
 59P/Kearns--Kwee   & 20.86~$\pm$~0.05 & 0.79~$\pm$~0.03 & 
   0.62~$\pm$~0.07 & -- & 0.27~$\pm$~0.08 \\ 
 63P/Wild 1         & 19.17~$\pm$~0.02 & 1.46~$\pm$~0.03 &
   0.50~$\pm$~0.05 & -- & 0.42~$\pm$~0.04 \\ 
 71P/Clark          & 21.83~$\pm$~0.07 & 0.68~$\pm$~0.04 & 
   0.64~$\pm$~0.07 & -- & -- \\
 84P/Giclas         & 20.59~$\pm$~0.04 & 0.90~$\pm$~0.05 &
   0.32~$\pm$~0.03 & -- & -- \\ 
106P/Schuster       & 18.91~$\pm$~0.03 & 0.94~$\pm$~0.03 &
   0.52~$\pm$~0.06 & 1.01~$\pm$~0.06 & 0.45~$\pm$~0.06 \\ 
112P/Urata--Niijima & 20.96~$\pm$~0.04 & 0.90~$\pm$~0.05 &
   0.53~$\pm$~0.04 & -- & -- \\ 
114P/Wiseman--Skiff & 19.73~$\pm$~0.04 & 0.78~$\pm$~0.05 &
   0.46~$\pm$~0.02 & 0.85~$\pm$~0.03 & 0.54~$\pm$~0.02 \\  
\hline\end{tabular}}
\smallskip
 $R_{\rm app}$: apparent magnitude of the nucleus in the
Johnson--Kron--Cousins photometric system.   \\
 $r_{\rm n}$: effective radius of the nucleus assuming
$p_R = 0.04$, $\beta = 0.040$~mag/deg except 10P/Tempel 2   $(V-R)$, $(B-V)$, $(R-I)$: color indices. 
 \\
  $^*$using $p_R = 0.024$ as measured independently. 
\end{table}