\begin{table}%t3
\par
\caption{\label{ion_LIS}CR ionization rates $\zeta^{{\rm H}_2}_k$ 
and $\zeta^{\rm He}_k$, %(per H$_2$ and per He, respectively),
electron production rate $\zeta^{\rm e}_k$, and energy densities ${\cal E}_k$ 
of CR protons$^{a}$ (p) and  electrons (e). 
%for the LIS spectra assumed in this work.
}
%\centerline
{
\begin{tabular}{lllllll}
\hline\hline\noalign{\smallskip}
$k$   &  Ref.      & $\zeta_k^{{\rm H}_2}$   & $\zeta_k^{\rm He}$     & $\zeta_k^{\rm e}$  & ${\cal E}_k$   \\                &            & (s$^{-1}$)              & (s$^{-1}$)             & (s$^{-1}$)   & (eV~cm$^{-3}$) \\
\hline\noalign{\smallskip}
p &      W98   & $2.08\times 10^{-17}$   & $1.33\times 10^{-17}$  & $2.50\times 10^{-17}$ & 0.953 \\
p &      M02   & $1.48\times 10^{-14}$   & $2.16\times 10^{-15}$  & $3.49\times 10^{-15}$ & 1.23  \\
\hline\noalign{\smallskip}
e   &    C00   & $1.62\times 10^{-19}$   & $1.05\times 10^{-19}$  & $1.94\times 10^{-19}$ & 0.0167 \\
e   &    E00   & $6.53\times 10^{-12}$   & $2.46\times 10^{-12}$  & $7.45\times 10^{-12}$ & 0.571 \\
\hline
\end{tabular}}
\medskip
$^a$ The proton ionization rates include
the contribution of heavy nuclei.
\end{table}