\begin{table}%t1
\caption{Experimental radiative lifetimes of four levels in Os~I.}\label{oslifetimes}
%\centerline
{\begin{tabular}{lccccrlrr}
\hline \hline \noalign{\smallskip}
Level$^a$ & Energy & $J$ & $\lambda_{\rm exc}^b$ & $\lambda_{\rm obs}^c$ &
\multicolumn{4}{c}{Lifetime (ns): Exp$^d$}\\ %&\multicolumn{1}{c}{Theory}          \\
\cline{6-9}\noalign{\smallskip}
& (cm$^{-1}$)& & (\AA) & (\AA)   & \multicolumn{2}{c}{This work}  &
\multicolumn{1}{c}{K} & \multicolumn{1}{c}{CB}      \\ %& \multicolumn{1}{c}{this work}\\
\noalign{\smallskip} \hline \noalign{\smallskip}
5d$^{5}$6s$^{2}$($^{6}$S)6p z $^{7}{\rm P}_{4}$& 28~331.736 & 4.0 & 4311.3 & 4135
&265&\hspace{-4mm}(20)& 238.0(12) & 70.2 \\ %& 195.4\\
5d$^{6}$6s($^{6}$D)6p z $^{7}{\rm F}_{5}$      & 30~279.921 & 5.0 & 3301.5 & 3977 &
93&\hspace{-4mm} (7)&  91.0 (5) & 27.5 \\ %& 65.8\\
5d$^{6}$6s($^{6}$D)6p z $^{7}{\rm F}_{4}$      & 32~684.629 & 4.0 & 3058.6 & 3504 &
28&\hspace{-4mm} (2)&  27.3 (2) &  9.6 \\ %& 24.0\\
5d$^{6}$6s($^{6}$D)6p z $^{5}{\rm F}_{5}$      & 34~365.335 & 5.0 & 2909.0 & 2909 &
24&\hspace{-4mm} (2)&           &      \\ 
 \hline 
\end{tabular}}
{$^a$ Level notation from \citet{Kleef61}.} \\
{$^b$ Laser wavelength used to populate the upper state.} \\
{$^c$ Wavelength used to detect the fluorescence signal.} \\
{$^d$ K = Kwiatkowski et~al. (1984), CB = Corliss \& Bozman (1962).}
\end{table}