\begin{table}%t1
%\centering
\par
\caption{ Simulations of circularly polarised Alfv\'{e}n waves in a  
stratified medium with density $\rho_0 (0)= 5 \times 10^{-13}~$ kg m$^{-3}$ at 
the bottom of the grid. $\Delta t, N$ and $L$ denote the time step measured in seconds, 
the number of grid points, and the length of the computational domain in
scale heights, $H$, respectively.
The vertical magnetic field, $B_0$, is given in T.
$v_{\rm A0}$ , $\beta_0$ and $\eta_0= B_\perp/B_0$ are computed at $z = 0$.\label{tab1}}
\begin{tabular}{llcllllll} 
\hline\hline
Run & $\Delta t$ (s) & $N$ & $L$ ($H$) & $B_0$~(T) & $v_{\rm A0} $(m s$^{-1}$) &$\eta_0$  & $\beta_0$\\ 
\hline
1a  & 0.0625 & 21~600 & 50 & $3 \times 10^{-5}$ &$3.8 \times 10^4$ &  0.007 & 23\\
1b  & 0.0625 & 21~600 & 50 & $3 \times 10^{-5}$ &$3.8 \times 10^4$ &  0.07 & 23\\
1c  & 0.0625 & 21~600 & 50 & $3 \times 10^{-5}$ & $3.8 \times 10^4$ & 0.7 & 23\\
2a & 0.125  &21~600  & 50 & $1.5 \times 10^{-5}$ &$1.8 \times 10^4$ &0.007  &82\\
2b & 0.125  &21~600  & 50 & $1.5 \times 10^{-5}$ &$1.8 \times 10^4$ &0.07  &82\\
2c & 0.125  &21~600  & 50 & $1.5 \times 10^{-5}$ &$1.8 \times 10^4$ &0.7  &82\\ 
\hline
\end{tabular}
\end{table}