\begin{table}%t1
\caption{\label{tab_par}Free parameters.}
%\centering
\par
\begin{tabular}{ccccccc}
\hline \hline \noalign{\smallskip}
Parameter & Meaning & Best-fit value & Range \\
\hline 
$\alpha_{\rm quie}$  & star formation & 0.01 & 0.01--0.1 \\
$\beta_{\rm burst}$ & burst efficiency & 0.68 & 0.5--1\\
$\epsilon_{\rm SN}$  & SN feedback efficiency & 0.5 & 0.01--1 \\
$f_{\rm BH} $  & AGN feedback efficiency in QSO mode & 0.006 & 0.001--0.1\\
$k_{\rm AGN} $  &  AGN feedback efficiency in radio mode & $1\times
 10^{-6}$ & $10^{-7}{-}10^{-6} $ \\
\hline 
\end{tabular}
\end{table}