\begin{table}%t3
 \caption{\label{table:wblmis}Stdev $\sigma_{we}$ of white noise baseline error.}
  %\centering
\small
 \begin{tabular}{cccc}
 \hline\hline
 $\tbase$ & $a$ and $b$ & $(a+b)/2$ & $(a-b)/2$ \\
          & ($\mu$K) & ($\mu$K) & ($\mu$K) \\
 \hline
 2.5 s   & 10.244 & 5.916 & 8.354 \\
 15 s    & 3.595  & 2.063 & 2.944 \\
 1 min   & 1.854  & 1.066 & 1.517 \\
 1 h     & 1.719  & 0.989 & 1.406 \\
 \hline
 \end{tabular}
\end{table}