\begin{table}%t2
      \caption{\label{table2}The effective thicknesses and the mass-to-light ratios of NGC~1566 and NGC~5247 ($B$-band).}
                   $$
         \begin{array}{p{0.15\linewidth}ccccccccccc}
            \hline
            \hline
           NGC &   m  & \phi &r_0      & \Lambda &    \alpha     & z_0   & \gamma                \\
    &      &  (^0)&(\rm{kpc})    &         &  (\rm{kpc^{-1}})  & (\rm{kpc}) &({M_\odot~ L_\odot ^{-1}}) \\
 (1)&  (2) & (3) & (4)  &   (5)   & (6)  &  (7)  &  (8)                           \\
                     \hline
        1566 & 2   & 32.3 & 0.996   &6.82     &  7.018       & 0.285 & 4.86\sim 8.99          \\
5247 & 2   & 23.0 & 0.358   &4.25     &  13.072      & 0.153 & 5.02\sim 6.90          \\
  \hline
         \end{array}
     $$
\begin{list}{}{}
\item  [$^{\star}$] Column 2: $m$ is the number of spiral arms.
\item  [$^{\star}$] Column 3: $\phi$ is the optimum inclination of the galactic disk.
\item  [$^{\star}$] Column 4: $r_0$ is the forbidden radius.
\item  [$^{\star}$] Column 5: $\Lambda$ is the winding parameter of spiral
arms, and pitch angle $\mu=\arctan (m/\Lambda)$.
\item  [$^{\star}$] Column 6: $\alpha$ is the thickness factor,
$\alpha=2/z_0$.
\item  [$^{\star}$] Column 7: $z_0$ is the effective thickness of the galactic
disk, and here, errors ($\bigtriangleup z_0$) of $z_0$ are
$\bigtriangleup z_{0({\rm NGC~1566})}=20.3\%$ and $\bigtriangleup
z_{0({\rm NGC~5247})}=18.1\%$.
\end{list}
   \end{table}