\begin{table}%t8
\caption{Comparison of the optical and X-ray  spectral indices 
($ {\rm \alpha^{O}_{\nu}}$, ${\rm \alpha^{X}_{\nu}}$),   
luminosities (${L^{\rm O}}$, $ {L^{\rm X}} $),  efficiencies (${ \rm \eta ^{O} } $, ${ \rm \eta ^{X} } $), 
and a weighted ratio ($ {L^{\rm O}\Delta E^{\rm X}/L^{\rm X}\Delta E^{\rm O}} $) of the two young pulsars, Crab and \psr, 
and the older Vela pulsar. Here $\Delta E^{\rm O}$ and $\Delta E^{\rm X}$ are
the energy intervals in the optical$^a$ and X-rays$^b$, respectively, used for
the frequency integration to obtain $L^{\rm O}$ and $L^{\rm X}$.
Information on the period $P$, dynamical age $ {\rm \tau } $, spindown 
luminosity $\dot E$, and distance $d$ for each pulsar is included.}  
\label{t:psr-lum}
%\begin{center}
{
\begin{tabular}{lccccccccccc}
\hline\hline
PSR & $P$ & ${\rm \tau}$ & ${\dot E}$ & $d$ & ${\rm \alpha^{O}_{\nu}}$  
& ${L^{\rm O,a}}$ & ${\rm \eta ^{O}}$ & ${\alpha^{\rm X}_{\nu}}$ & ${L^{\rm X,b}}$  
& ${ \rm \eta ^{X}}$ & ${L^{\rm O}\Delta E^{\rm X} \over L^{\rm X}\Delta E^{\rm O}}$  \\   
% 
  & ms & kyr & ${\rm 10^{37}~erg~s^{-1}}$ & kpc &   & ${\rm 10^{33}~erg~s^{-1}} $  & ${\rm  10^{-5}  } $  &   
  & ${\rm 10^{36}~erg~s^{-1}} $   & ${\rm  10^{-3}  } $  &   \\
% 
\hline  
%
Crab &  33.49  & 1.24 & 46  & 2 & $-0.21^c$  & 7.9$^c$  & 1.7 & 0.87$^d$  & 1.0$^d$ & 2.17 & 34.9  \widerul\\
%
0540  &  50.2  & 1.66 & 15 & 51 &  1.07$^e$  & 10.9$^e$  &  7.3 & 0.83$^d$  & 3.13$^d$ & 21  & 15.5  \widerul\\    
%
Vela  &  89  & 11 &  0.69 & 0.29 & 0.25$^f$   &  ${\rm 7.0^f\times 10^{-5}}$ & ${\rm 1.0\times 10^{-3}}$  & 0.5$^g$  & 
${\rm 2.3^g\times 10^{-5}}$ & ${\rm 3.4 \times10^{-3}}$  & 13.5 \widerul\\   
\hline
\end{tabular}}
\smallskip
\begin{tabular}{ll}
$^a$~For the optical range 1.57--3.68 eV. & $^e$~This paper.\\ 
$^b$~For the X-ray range 0.6--10 keV. & $^f$~Using data from Shibanov et~al. (2003). \\
$^c$~Using data from Sollerman (2003) for 1.57--3.68 eV. & $^g$~Pavlov et~al.~(2001a); ${L^{\rm X}}$ rescaled to the 0.6--10 keV range \\
$^d$~Kaaret et~al. (2001); $ {L^{\rm X}}$ rescaled to the 0.6--10 keV range. & and $d=0.29$~kpc.\\
\end{tabular}
%\end{center}
\par
\end{table}