\begin{table}%t9
\par
\caption{\label{elements}Physical parameters of various short-period
  (SP) and long-period (LP) radiogenic elements considered in the
  model. }
%\centering
\par
%\renewcommand{\footnoterule}{}
\begin{tabular}{ccccc}
\hline
\hline
\noalign{\smallskip}
   &  \multirow{2}*{Element} & \multirow{2}*{$X_{\rm rad}$($t=0$)\tablefootmark{a}} & $\tau _{\rm rad}$\tablefootmark{b} & $H_{\rm rad}$\tablefootmark{c} \\
   &                  &                       &   (years)     &        J~kg$^{-1}$           \\
\hline 
\multirow{3}*{SP}
&~{}$^{26}$Al    & 6.7~$\times$~10$^{-7}$    &1.05~$\times$~10$^{6}$&4.84~$\times$~10$^{12}$\\
&~{}$^{60}$Fe   & ~~~~2.5~$\times$~10$^{-7/-8}$&2.16~$\times$~10$^{6}$&5.04~$\times$~10$^{12}$\\
&~~{}$^{53}$Mn  & 2.8~$\times$~10$^{-8}$    &5.34~$\times$~10$^{6}$&4.55~$\times$~10$^{12}$\\
\hline
\multirow{4}*{LP}
&{}$^{40}$K    & 1.2~$\times$~10$^{-6}$&1.80~$\times$~10$^{9}$  &1.66~$\times$~10$^{12}$\\
&{}$^{232}$Th& 6.0~$\times$~10$^{-8}$&~2.02~$\times$~10$^{10}$&1.68~$\times$~10$^{13}$\\
&{}$^{235}$U~  & 9.0~$\times$~10$^{-9}$&1.02~$\times$~10$^{9}$  &1.82~$\times$~10$^{13}$\\
&{}$^{238}$U~  & 2.9~$\times$~10$^{-8}$&6.45~$\times$~10$^{9}$  &1.92~$\times$~10$^{13}$\\
\hline
\end{tabular}
\tablefoot{
Values adapted from \citet{Castillo+07}.
\tablefoottext{a}{Initial mass fraction of the radiogenic element.}
\tablefoottext{b}{Decay time.}
\tablefoottext{c}{Heat released by this radiogenic element per unit mass upon decay.}
}
\end{table}