\begin{table}%t1
\caption{The values of $\eta $ at the three critical position.}\label{table1}
%\centering
\par
\begin{tabular}{l|lll|lll}
\hline\hline 
\multicolumn{1}{c}{} & \multicolumn{3}{c}{the CNO
Models} & \multicolumn{3}{c}{the CN Models} \\
$Z$ & $\eta _{\rm a}$ & $\eta _{\rm c}$ & $\eta _{{\rm min}}$ & $\eta _{\rm a}'$ & $\eta _{\rm c}'$ & $\eta
_{min}'$ \\ \hline
\multicolumn{7}{c}{$Y=0.28$} \\
.020 & .9388 & .3171 & .0000 & .9062 & .5248 & .5157 \\
.018 & .9317 & .3373 & .1993 & .8948 & .5187 & .4978 \\
.016 & .9228 & .3926 & .3636 & .8809 & .4889 & .4573 \\
.014 & .9120 & .4608 & .4349 & .8652 & .4614 & .3960 \\
.012 & .8986 & .4863 & .4627 & .8484 & .4292 & .2983 \\
.010 & .8824 & .4748 & .4324 & .8280 & .4147 & .0000 \\
.008 & .8527 & .4284 & .2878 & .7865 & .3937 & .0000 \\
.006 & .8122 & .4058 & .0000 & .7274 & .3684 & .0000 \\
.004 & .7483 & .3749 & .0000 & .6372 & .3528 & .0000 \\ \hline
\multicolumn{7}{c}{$Y=0.26$} \\
.020 & .9430 & .2917 & .0000 & .9127 & .5238 & .5166 \\
.018 & .9364 & .3046 & .0000 & .9002 & .5268 & .5147 \\
.016 & .9278 & .3548 & .3224 & .8859 & .5026 & .4823 \\
.014 & .9177 & .4303 & .4240 & .8698 & .4647 & .4237 \\
.012 & .9040 & .4884 & .4776 & .8524 & .4313 & .3478 \\
.010 & .8868 & .4833 & .4614 & .8325 & .4073 & .2290 \\
.008 & .8566 & .4316 & .3409 & .7923 & .3818 & .0000 \\
.006 & .8174 & .3915 & .0000 & .7330 & .3600 & .0000 \\
.004 & .7527 & .3626 & .0000 & .6455 & .3414 & .0000 \\ \hline
\multicolumn{7}{c}{$Y=0.23$} \\
.020 & .9488 & .2589 & .0000 & .9219 & .4981 & .4952 \\
.018 & .9425 & .2690 & .0000 & .9097 & .5279 & .5234 \\
.016 & .9352 & .2856 & .2085 & .8953 & .5171 & .5071 \\
.014 & .9258 & .3872 & .3814 & .8786 & .4853 & .4634 \\
.012 & .9129 & .4716 & .4705 & .8592 & .4382 & .3992 \\
.010 & .8953 & .4992 & .4883 & .8380 & .3942 & .3094 \\
.008 & .8641 & .4350 & .3943 & .8005 & .3601 & .0000 \\
.006 & .8238 & .3778 & .1913 & .7404 & .3439 & .0000 \\
.004 & .7616 & .3411 & .0000 & .6546 & .3220 & .0000 \\ \hline
\end{tabular}
\end{table}