\begin{table}%t1
%\centering
\par
\caption{Average number of elementary charges
given to the targets made of aluminum (Al), iron (Fe), 
or graphite (C) by a particle of nominal size $d_{n}$ (i.e. positive sign
means that the target  charged positively, the particle negatively).
The precharge is the number of elementary charges given 
on average to the cogwheel. Error is
$\pm $$13$\%.
\label{ergebnis}}
%\centering
\par
\begin{tabular}{c c c c c c c c c}
\hline \hline
Code &Material&$d_{n}$      &Particle mass&Velocity     &Precharge&Al  &Fe  &C\\
     &        &$\rm \mu m$&kg  &m s$^{-1}$&&&&\\
\hline
a&$\rm SiO_2$&0.70& $3.6\times 10^{-16}$& 49&  61&  130&  118&   35\\
\par
b&$\rm SiO_2$&0.70& $3.6\times 10^{-16}$& 69& 161&  432&  301&   32\\
\par
c&$\rm SiO_2$&1.52& $3.7\times 10^{-15}$& 59& 601& 1561& 1254&  125\\
\par
d&$\rm SiO_2$&1.52& $3.7\times 10^{-15}$&106&1557& 3058& 3166&  --54\\
\par
e&diamond    &1.55& $6.1\times 10^{-15}$& 38& 1335& 2939& 1941& 2673\\
\par
f&diamond    &1.55& $6.1\times 10^{-15}$& 67& 1585& 3378& 2085& 2763\\
\par
g&graphite   &1.44& $3.4\times 10^{-15}$& 38&  826& 2456& 1821&  415\\
\par
h&graphite   &1.44& $3.4\times 10^{-15}$& 67& 1022& 3335& 1842&  62\\
\par
i&SiC        &1.02& $1.7\times 10^{-15}$& 38&  128&  318&  382&  340\\
\par
j&SiC        &1.02& $1.7\times 10^{-15}$& 67&  219&  378&  393&  375\\
\hline
\end{tabular}
\end{table}