\begin{table}%t4
%\centering
\par
\caption{\label{checkalpha}Fit parameters for structure functions from different simulation 
settings.}
\small \begin{tabular}{rrrrr}
\hline\hline
\multicolumn{5}{c}{$L=20$~pc, $r_{\rm max}=10$~kpc}\\
\hline
 $\Delta$ (pc) & $C$ & $\Delta C$ & $m$  & $\Delta m$ \\
\hline 
    0.80  & 3.304 &  0.028 &  0.727 &   0.044\\
    0.40  & 3.430 &  0.021 &  0.644 &   0.033\\
    0.20  & 3.387 &  0.030 &  0.760 &   0.047\\
    0.10  & 3.414 &  0.009 &  0.612 &   0.014\\
    0.05  & 3.447 &  0.018 &  0.622 &   0.028\\
\hline
\multicolumn{5}{c}{$\Delta=0.5$~pc, $r_{\rm max}=10$~kpc} \\\hline
 $L$ (pc) & $C$ & $\Delta C$ & $m$  & $\Delta m$ \\\hline 
  200     & 2.830 & 0.006 &  1.262 &   0.006\\ 
  100     & 3.045 & 0.011 &  1.081 &   0.015\\
  50      & 3.201 & 0.008 &  0.982 &   0.010\\
  25      & 3.401 & 0.007 &  0.709 &   0.012\\
\hline\noalign{\smallskip}
\multicolumn{5}{c}{$\Delta=0.25$~pc, $L=100$~pc} \\
\hline
 $r_{\rm max}$ (kpc) & $C$ & $\Delta C$ & $m$  & $\Delta m$ \\
\hline 
  0.01 &  $-$6.270 &  0.0181 & 1.660 &  0.014\\
  0.05 &  $-$4.243 &  0.0106 & 1.413 &  0.008\\
  0.10 &  $-$2.689 &  0.0128 & 1.668 &  0.009\\
  0.20 &  $-$1.742 &  0.0172 & 1.355 &  0.013\\
  0.40 &  $-$1.206 &  0.0202 & 1.689 &  0.013\\ 
  0.80 &     0.368 &  0.0133 & 1.282 &  0.012\\
  1.60 &     1.630 &  0.0088 & 1.330 &  0.009\\
  3.20 &     2.711 &  0.0060 & 1.154 &  0.006\\
  6.40 &     2.970 &  0.0083 & 1.151 &  0.010\\
 10.00 &     3.083 &  0.0078 & 1.081 &  0.010\\
\hline 
\end{tabular}
\end{table}