\begin{table}%t12
%\centering
\par
\caption{\label{tab_energy_kr}The level energies (Ryd) of Kr$^{26+}$ from 
different calculations along with the compilation of NIST v3. }
{\tiny 
\begin{tabular}{cccccc}
\hline\hline \noalign{\smallskip}
ID  &   Level~specification  & NIST\tablefootmark{a} & AS   & FAC   & MCDF\tablefootmark{b}  \\
\hline\noalign{\smallskip}
   1 & ${\rm     2s^2 2p^6 ~ ^1S_0}$ &             & 0.000        &                &            \\
   2 & ${\rm  2s^2 2p^5 3s ~ ^3P_2}$ &   121.204   & 121.384      &   121.242      &   121.192  \\
   3 & ${\rm  2s^2 2p^5 3s ~ ^1P_1}$ &   121.441   & 121.592      &   121.482      &   121.426  \\
   4 & ${\rm  2s^2 2p^5 3p ~ ^3S_1}$ &   124.966   & 125.274      &   125.019      &   124.964  \\
   5 & ${\rm  2s^2 2p^5 3s ~ ^3P_0}$ &   125.284   & 125.452      &   125.283      &   125.303  \\
   6 & ${\rm  2s^2 2p^5 3p ~ ^3D_2}$ &   125.194   & 125.503      &   125.250      &   125.200  \\
   7 & ${\rm  2s^2 2p^5 3s ~ ^3P_1}$ &   125.399   & 125.562      &   125.406      &   125.430  \\
   8 & ${\rm  2s^2 2p^5 3p ~ ^3D_3}$ &   126.041   & 126.352      &   126.097      &   126.072  \\
   9 & ${\rm  2s^2 2p^5 3p ~ ^1P_1}$ &   126.084   & 126.370      &   126.136      &   126.100  \\
  10 & ${\rm  2s^2 2p^5 3p ~ ^3P_2}$ &   126.397   & 126.686      &   126.449      &   126.410  \\
  11 & ${\rm  2s^2 2p^5 3p ~ ^3P_0}$ &   127.618   & 127.907      &   127.633      &   127.588  \\
  12 & ${\rm  2s^2 2p^5 3p ~ ^3D_1}$ &   129.175   & 129.491      &   129.194      &   129.225  \\
  13 & ${\rm  2s^2 2p^5 3p ~ ^3P_1}$ &   130.192   & 130.485      &   130.208      &   130.241  \\
  14 & ${\rm  2s^2 2p^5 3p ~ ^1D_2}$ &   130.280   & 130.582      &   130.302      &   130.347  \\
  15 & ${\rm  2s^2 2p^5 3d ~ ^3P_0}$ &   130.694   & 131.065      &   130.788      &   130.745  \\
  16 & ${\rm  2s^2 2p^5 3p ~ ^1S_0}$ &   130.742   & 131.105      &   130.936      &   130.908  \\
  17 & ${\rm  2s^2 2p^5 3d ~ ^3P_1}$ &   130.945   & 131.257      &   130.961      &   130.936  \\
  18 & ${\rm  2s^2 2p^5 3d ~ ^3F_3}$ &   131.173   & 131.523      &   131.236      &   131.232  \\
  19 & ${\rm  2s^2 2p^5 3d ~ ^3P_2}$ &   131.233   & 131.589      &   131.282      &   131.266  \\
  20 & ${\rm  2s^2 2p^5 3d ~ ^3F_4}$ &   131.214   & 131.622      &   131.267      &   131.274  \\
  21 & ${\rm  2s^2 2p^5 3d ~ ^1D_2}$ &   131.445   & 131.803      &   131.510      &   131.496  \\
  22 & ${\rm  2s^2 2p^5 3d ~ ^3D_3}$ &   131.664   & 132.059      &   131.728      &   131.723  \\
  23 & ${\rm  2s^2 2p^5 3d ~ ^3D_1}$ &   132.476   & 132.866      &   132.553      &   132.551  \\
  24 & ${\rm  2s^2 2p^5 3d ~ ^3F_2}$ &   135.260   & 135.550      &   135.239      &   135.304  \\
  25 & ${\rm  2s^2 2p^5 3d ~ ^3D_2}$ &   135.426   & 135.816      &   135.458      &   135.522  \\
  26 & ${\rm  2s^2 2p^5 3d ~ ^1F_3}$ &   135.531   & 135.929      &   135.567      &   135.640  \\
  27 & ${\rm  2s^2 2p^5 3d ~ ^1P_1}$ &   136.065   & 136.470      &   136.152      &   136.226  \\
  28 & ${\rm   2s 2p^6 3s  ~ ^3S_1}$ &             & 139.301      &   138.999      &   139.030  \\
  29 & ${\rm   2s 2p^6 3s  ~ ^1S_0}$ &             & 140.228      &   139.784      &   139.808  \\
  30 & ${\rm   2s 2p^6 3p  ~ ^3P_0}$ &             & 143.315      &   142.899      &   142.923  \\
  31 & ${\rm   2s 2p^6 3p  ~ ^3P_1}$ &   142.715   & 143.393      &   142.973      &   143.005  \\
  32 & ${\rm   2s 2p^6 3p  ~ ^3P_2}$ &             & 144.298      &   143.888      &   143.939  \\
  33 & ${\rm   2s 2p^6 3p  ~ ^1P_1}$ &   143.835   & 144.486      &   144.090      &   144.137  \\
  34 & ${\rm   2s 2p^6 3d  ~ ^3D_1}$ &             & 149.200      &   148.746      &   148.814  \\
  35 & ${\rm   2s 2p^6 3d  ~ ^3D_2}$ &             & 149.283      &   148.804      &   148.884  \\
  36 & ${\rm   2s 2p^6 3d  ~ ^3D_3}$ &             & 149.470      &   148.935      &   149.027  \\
  37 & ${\rm   2s 2p^6 3d  ~ ^1D_2}$ &   149.295   & 150.012      &   149.526      &   149.623  \\
  38 & ${\rm  2s^2 2p^5 4s ~ ^3P_2}$ &             & 164.741      &   164.395      &   164.361  \\
  39 & ${\rm  2s^2 2p^5 4s ~ ^1P_1}$ &   164.388   & 164.798      &   164.476      &   164.439  \\
  40 & ${\rm  2s^2 2p^5 4p ~ ^3S_1}$ &             & 166.296      &   165.965      &   165.929  \\
  41 & ${\rm  2s^2 2p^5 4p ~ ^3D_2}$ &             & 166.352      &   166.029      &   165.992  \\
  42 & ${\rm  2s^2 2p^5 4p ~ ^3D_3}$ &             & 166.663      &   166.375      &   166.350  \\
  43 & ${\rm  2s^2 2p^5 4p ~ ^1P_1}$ &             & 166.670      &   166.396      &   166.367  \\
  44 & ${\rm  2s^2 2p^5 4p ~ ^3P_2}$ &             & 166.771      &   166.503      &   166.469  \\
  45 & ${\rm  2s^2 2p^5 4p ~ ^1S_0}$ &             & 167.275      &   167.045      &   166.996  \\
  46 & ${\rm  2s^2 2p^5 4d ~ ^3P_0}$ &             & 168.441      &   168.136      &   168.116  \\
  47 & ${\rm  2s^2 2p^5 4d ~ ^3P_1}$ &   168.120   & 168.512      &   168.204      &   168.190  \\
  48 & ${\rm  2s^2 2p^5 4d ~ ^3F_3}$ &             & 168.591      &   168.295      &   168.284  \\
  49 & ${\rm  2s^2 2p^5 4d ~ ^3D_2}$ &             & 168.629      &   168.324      &   168.310  \\
  50 & ${\rm  2s^2 2p^5 4d ~ ^3F_4}$ &             & 168.644      &   168.319      &   168.314  \\
  51 & ${\rm  2s^2 2p^5 4d ~ ^1D_2}$ &             & 168.699      &   168.401      &   168.388  \\
  52 & ${\rm  2s^2 2p^5 4d ~ ^3D_3}$ &             & 168.793      &   168.484      &   168.473  \\
  53 & ${\rm  2s^2 2p^5 4s ~ ^3P_0}$ &             & 168.824      &   168.451      &   168.493  \\
  54 & ${\rm  2s^2 2p^5 4s ~ ^3P_1}$ &   168.376   & 168.833      &   168.470      &   168.510  \\
  55 & ${\rm  2s^2 2p^5 4d ~ ^1P_1}$ &   168.738   & 169.136      &   168.851      &   168.844  \\
  56 & ${\rm  2s^2 2p^5 4f ~ ^3D_1}$ &             & 169.620      &   169.348      &   169.319  \\
  57 & ${\rm  2s^2 2p^5 4f ~ ^1G_4}$ &             & 169.649      &   169.370      &   169.350  \\
  58 & ${\rm  2s^2 2p^5 4f ~ ^3D_2}$ &             & 169.661      &   169.386      &   169.359  \\
  59 & ${\rm  2s^2 2p^5 4f ~ ^3G_5}$ &             & 169.697      &   169.397      &   169.377  \\
  60 & ${\rm  2s^2 2p^5 4f ~ ^3F_3}$ &             & 169.711      &   169.440      &   169.414  \\
  \hline
\end{tabular}}
\tablefoot{\tablefootmark{a}{Sources of the NIST v3 compilation are from the work of %Saloman (
\citet{Sal07} and references therein. }
\tablefoottext{b}{MCDF data is from the work of 
\citet{GBM08}.}}
\end{table}